| 1. |
- Ablikim, M., et al.
(författare)
-
Observation of e(+)e(-) -> gamma X(3872) at BESIII
- 2014
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 112:9, s. 092001-
-
Tidskriftsartikel (refereegranskat)abstract
- With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process e(+)e(-) -> gamma X(3872) is observed for the first time with a statistical significance of 6.3 sigma. The measured mass of the X(3872) is (3871.9 +/- 0.7(stat) +/- 0.2(syst)) MeV/c(2), in agreement with previous measurements. Measurements of the product of the cross section sigma[e(+)e(-) -> gamma X(3872)] and the branching fraction B [X(3872) -> pi(+)pi(-)J/psi] at center-of-mass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process Y(4260) -> gamma X(3872).
|
|
| 2. |
- Ablikim, M., et al.
(författare)
-
Observation of eta' -> pi(+) pi(-) pi(+) pi(-) and eta' -> pi(+) pi(-) pi(0) pi(0)
- 2014
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 112:25, s. 251801-
-
Tidskriftsartikel (refereegranskat)abstract
- Using a sample of 1.3 x 10(9) J/psi events collected with the BESIII detector, we report the first observation of eta' -> pi(+) pi(-) pi(+) pi(-) and eta' -> pi(+) pi(-) pi(0) pi(0). The measured branching fractions are B(eta' -> pi(+) pi(-) pi(+) pi(-)) = [8.53 +/- 0.69(stat.) +/- 0.64(syst.)] x 10(-5) and B(eta' -> pi(+) pi(-) pi(0) pi(0)) = [1.82 +/- 0.35(stat.) +/- 0.18(syst.)] x 10(-4), which are consistent with theoretical predictions based on a combination of chiral perturbation theory and vector-meson dominance.
|
|
| 3. |
- Ablikim, M., et al.
(författare)
-
Observation of the decay psi(3686) -> Lambda(Sigma)over-bar(+/-) pi(-/+) + c.c
- 2013
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:11, s. 112007-
-
Tidskriftsartikel (refereegranskat)abstract
- Using a sample of 1:06 X 10(8) psi(3686) events collected with the BESIII detector, we present the first observation of the decays of psi(3686) -> Lambda(Sigma) over bar (+) pi(-) + c.c. and psi(3686) -> Lambda(Sigma) over bar (-) pi(+) + c.c. The branching fractions are measured to be B(psi(3686) -> Lambda(Sigma) over bar (+) pi(-) + c.c.) = (1.40 +/- 0.03 +/- 0.13) X 10(-4) and B(psi(3686) -> Lambda (Sigma) over bar (-) pi(+) + c.c.) = (1.54 +/- 0.04 +/- 0.13) X 10(-4) where the first errors are statistical and the second ones systematic.
|
|
| 4. |
- Ablikim, M., et al.
(författare)
-
Search for eta(c)(2S)h(c) -> p(p)over-bar decays and measurements of the chi(cJ) -> p(p)over-bar branching fractions
- 2013
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:11, s. 112001-
-
Tidskriftsartikel (refereegranskat)abstract
- Using a sample of 1.06 x 10(8)psi(3686) events collected with the BESIII detector at BEPCII, the decays eta(c)(2S) -> p (p) over bar and h(c) -> p (p) over bar are searched for, where eta(c)(2S) and h(c) are reconstructed in the decay chains psi(3686) -> gamma eta(c)(2S), eta(c)(2S) -> p (p) over bar and psi(3686) -> pi(0)h(c), h(c) -> p (p) over bar, respectively. No significant signals are observed. The upper limits of the product branching fractions are determined to be B(psi(3686) -> gamma eta(c)(2S)) x B(eta(c)(2S) -> p (p) over bar) < 1.4 x 10(-6) and B(psi(3686) -> pi(0)h(c)) x B(h(c) -> p<(p)over bar>) < 1.3 x 10(-7) at the 90% C.L.. The branching fractions for chi(cJ) -> p<(p)over bar> (J = 0, 1, 2) are also measured to be (24.5 +/- 0.8 +/- 1.3, 8.6 +/- 0.5 +/- 0.5, 8.4 +/- 0.5 +/- 0.5) x 10(-5), which are the world's most precise measurements.
|
|
| 5. |
- Ablikim, M., et al.
(författare)
-
Amplitude analysis of the D+ -> K-S(0)pi + (0)(pi) Dalitz plot
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:5, s. 052001-
-
Tidskriftsartikel (refereegranskat)abstract
- We perform an analysis of the D+ -> K-S(0)pi + (0)(pi) Dalitz plot using a data set of 2.92 fb(-1) of e(+) e(-) collisions at the (3770) mass accumulated by the BESIII experiment, in which 166694 candidate events are selected with a background of 15.1%. The Dalitz plot is found to be well represented by a combination of six quasitwo- body decay channels [k(SP)(0)(+) (1450)(+,) ] plus a small nonresonant component. Using the fit fractions from this analysis, partial branching ratios are updated with higher precision than previous measurements.
|
|
| 6. |
- Ablikim, M., et al.
(författare)
-
Measurement of chi(cJ) decaying into eta ' K+K-
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:7, s. 074030-
-
Tidskriftsartikel (refereegranskat)abstract
- Using (106.41 +/- 0.86) x 10(6) Psi(3686) events collected with the BESIII detector at BEPCII, we study for the first time the decay chi(cJ) -> eta'K+K- (J = 1, 2), where eta' -> gamma rho(0) and eta' -> eta pi(+)pi(-). A partial wave analysis in the covariant tensor amplitude formalism is performed for the decay chi(c1) -> eta'K+K-. Intermediate processes chi(c1) -> eta'f(2)'(1525) chi(c1) -> K-0*(1430)K-+/-(-/+) (K-0*(1430)(+/-) -> eta'K-+/-) are observed with statistical significances larger than 5 sigma, and their branching fractions are measured.
|
|
| 7. |
- Ablikim, M., et al.
(författare)
-
Measurement of the branching fraction for psi(3686) -> omega K+K-
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:11, s. 112006-
-
Tidskriftsartikel (refereegranskat)abstract
- With 1.06 x 10(8) psi(3686) events collected with the BESIII detector, the branching fraction of psi(3686) -> omega K+K- is measured to be (1.54 +/- 0.04 +/- 0.11) x 10(-4). This is the most precise result to date, due to the largest psi(3686) sample, improved signal reconstruction efficiency, good simulation of the detector performance, and a more accurate knowledge of the continuum contribution. Using the branching fraction of J/psi -> omega K+K-, the ratio B(psi(3868) -> K+K-)/B(J/psi -> K+K-) is determined to be (18.4 +/- 3.7)%. This constitutes a significantly improved test of the 12% rule, with the uncertainty now dominated by the J/psi branching fraction.
|
|
| 8. |
- Ablikim, M., et al.
(författare)
-
Measurement of the $D\to K^-\pi^+$ strong phase difference in $\psi(3770)\to D^0\overline{D}{}^0$
- 2014
-
Ingår i: PHYSICS LETTERS B. - : Elsevier BV. - 0370-2693. ; 734
-
Tidskriftsartikel (refereegranskat)abstract
- We study $D^0\overline{D}{}^0$ pairs produced in $e^+e^-$ collisions at $\sqrt{s}=3.773$ GeV using a data sample of 2.92 fb$^{-1}$ collected with the BESIII detector. We measure the asymmetry $\mathcal{A}^{CP}_{K\pi}$ of the branching fractions of $D \to K^-\pi^+$ in $CP$-odd and $CP$-even eigenstates to be $(12.7\pm1.3\pm0.7)\times10^{-2}$. $\mathcal{A}^{CP}_{K\pi}$ can be used to extract the strong phase difference $\delta_{K\pi}$ between the doubly Cabibbo-suppressed process $\overline{D}{}^{0}\to K^-\pi^+$ and the Cabibbo-favored process $D^0\to K^- \pi^+$. Using world-average values of external parameters, we obtain $\cos\delta_{K\pi} = 1.02\pm0.11\pm0.06\pm0.01$. Here, the first and second uncertainties are statistical and systematic, respectively, while the third uncertainty arises from the external parameters. This is the most precise measurement of $\delta_{K\pi}$ to date.
|
|
| 9. |
- Ablikim, M., et al.
(författare)
-
Observation of $e^+e^− → γX$(3872) at BESIII
- 2014
-
Ingår i: PHYSICAL REVIEW LETTERS. - 1079-7114. ; 112:9
-
Tidskriftsartikel (refereegranskat)abstract
- With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process $e^{+} e^{-} \to \gamma X(3872)$ is observed for the first time with a statistical significance of $6.3\sigma$. The measured mass of the $X(3872)$ is ($3871.9\pm 0.7_{\rm stat.}\pm 0.2_{\rm sys.}$) MeV/$c^2$, in agreement with previous measurements. Measurements of the product of the cross section $\sigma[e^{+} e^{-} \to \gamma X(3872)]$ and the branching fraction $\mathcal{B}[X(3872) \to \pi^{+} \pi^{-} J/\psi]$ at center-of-mass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process $Y(4260) \to \gamma X(3872)$.
|
|
| 10. |
- Ablikim, M., et al.
(författare)
-
Observation of electromagnetic Dalitz decays J/\psi \to P e^+e^-
- 2014
-
Ingår i: PHYSICAL REVIEW D. - 2470-0010 .- 1550-7998 .- 1550-2368. ; 89:9
-
Tidskriftsartikel (refereegranskat)abstract
- Based on a sample of (225.3\pm2.8)\times 10^{6} J/\psi events collected with the BESIII detector, the electromagnetic Dalitz decays of J/\psi \to P e^+e^-(P=\eta'/\eta/\pi^0) are studied. By reconstructing the pseudoscalar mesons in various decay modes, the decays J/\psi \to \eta' e^+e^-, J/\psi \to \eta e^+e^- and J/\psi \to \pi^0 e^+e^- are observed for the first time. The branching fractions are determined to be \mathcal{B}(J/\psi\to \eta' e^+e^-) = (5.81\pm0.16\pm0.31)\times10^{-5}, \mathcal{B}(J/\psi\to \eta e^+e^-) = (1.16\pm0.07\pm0.06)\times10^{-5}, and \mathcal{B}(J/\psi\to \pi^0 e^+e^-)=(7.56\pm1.32\pm0.50)\times10^{-7}, where the first errors are statistical and the second ones systematic.
|
|
| 11. |
- Ablikim, M., et al.
(författare)
-
Observation of J/psi -> p(p)over-bara(0)(980) at BESIII
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:5, s. 052009-
-
Tidskriftsartikel (refereegranskat)abstract
- Using 2.25 x 10(8) J/psi events collected with the BESIII detector at the BEPCII storage rings, we observe for the first time the process J/psi -> p (p) over bara(0)(980) -> pi(0)eta with a significance of 6.5 sigma (3.2 sigma including systematic uncertainties). The product branching fraction of J/psi -> p (p) over bara(0)(980) -> p (p) over bara(0)pi(0)eta is measured to be (6.8 +/- 1.2 +/- 1.3) x 10(-5), where the first error is statistical and the second is systematic. This measurement provides information on the a(0) production near threshold coupling to p (p) over bar and improves the understanding of the dynamics of J/psi decays to four-body processes.
|
|
| 12. |
- Ablikim, M., et al.
(författare)
-
Precision measurement of the mass of the tau lepton
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:1
-
Tidskriftsartikel (refereegranskat)abstract
- An energy scan near the tau pair production threshold has been performed using the BESIII detector. About 24 pb(-1) of data, distributed over four scan points, were collected. This analysis is based on t pair decays to ee, e mu, eh, h, hh, e.,. and p. final states, where h denotes a charged p or K. The mass of the t lepton is measured from a maximum likelihood fit to the t pair production cross- section data to be m(tau) = 1776.91 +/- 0.12_0.10 - 0.13 _ MeV/c(2), which is currently the most precise value in a single measurement.
|
|
| 13. |
- Ablikim, M., et al.
(författare)
-
Precision measurements of $B(D^+ \rightarrow \mu^+ \nu_{\mu})$, the pseudoscalar decay constant $f_{D^+}$, and the quark mixing matrix element $|V_{\rm cd}|$
- 2014
-
Ingår i: PHYSICAL REVIEW D. - 2470-0010 .- 1550-7998 .- 1550-2368. ; 89:5
-
Tidskriftsartikel (refereegranskat)abstract
- We report a measurement of the branching fraction $B(D^+ \rightarrow \mu^+ \nu_{\mu}) = [3.71 \pm 0.19 (\rm stat) \pm 0.06 (\rm sys)]\times 10^{-4}$ based on 2.92 ${\rm fb^{-1}}$ of data accumulated at $\sqrt{s}=3.773$ GeV with the BESIII detector at the BEPCII collider. This measurement, in conjunction with the Cabibbo-Kobayashi-Maskawa matrix element $|V_{\rm cd}|$ determined from a global Standard Model fit, implies a value for the weak decay constant $f_{D^+}=(203.2 \pm 5.3 \pm 1.8)$ MeV. Additionally, using this branching fraction measurement together with a Lattice QCD prediction for $f_{D^+}$, we find $|V_{\rm cd}|=0.2210\pm 0.0058 \pm 0.0047$. In either case, these are the most precise results for these quantities to date.
|
|
| 14. |
- Ablikim, M., et al.
(författare)
-
Search for the radiative transitions Psi(3770) -> gamma eta(c) and gamma eta(c) (2S)
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:11, s. 112005-
-
Tidskriftsartikel (refereegranskat)abstract
- By using a 2.92 fb-1 data sample taken at pffisffiffi 3.773 GeV with the BESIII detector operating at the BEPCII collider, we search for the radiative transitions.d3770c and cd2S through the hadronic decays cdcd2S. K0 SK p. No significant excess of signal events above background is observed. We set upper limits at a 90% confidence level for the product branching fractions to be Bdd3770cxBd.c. K0 SK k p < 1.6x10-5 and Bd.d3770cd2SxBd.cd2S. K0 SK p<5.6x10-6. Combining our result with world-average values of Bd.cd.cd2S. K0 SK p, we find the branching fractions Bd.d3770c< 6.8 x 10-4 and Bd.d3770cd2S< 2.0 x 10-3 at a 90% confidence level.
|
|
| 15. |
- Ablikim, M., et al.
(författare)
-
Search for the rare decays J/y -> D-s(-) rho(+) and J/psi -> <(D)over bar(0)<(K)over bar*(0)
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:7, s. 071101-
-
Tidskriftsartikel (refereegranskat)abstract
- A search for the rare decays of J/psi -> D-S(-) rho(+) + c.c. and J/psi -> <(D)over bar(0)<(K)over bar*(0) + c.c. is performed with a data sample of 225.3-million J/psi events collected with the Beijing Spectrometer III detector. No evident signal is observed. Upper limits on the branching fractions are determined to be beta(J/psi -> D-S(-)rho(+) + c.c.) < 1.3 x 10(-5) and beta(J/psi -> <(D)over bar(0)<(K)over bar*(0) + c.c.) < 2.5 x 10(-6) at the 90% confidence level.
|
|
| 16. |
- Ablikim, M., et al.
(författare)
-
Study of e(+)e(-) -> p(p)over-bar in the vicinity of psi(3770)
- 2014
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 735, s. 101-107
-
Tidskriftsartikel (refereegranskat)abstract
- Using 2917 pb(-1) of data accumulated at 3.773 GeV, 44.5 pb(-1) of data accumulated at 3.65 GeV and data accumulated during a psi(3770) line-shape scan with the BESIII detector, the reaction e(+)e(-) -> p (p) over bar is studied considering a possible interference between resonant and continuum amplitudes. The cross section of e(+)e(-) -> psi(3770) -> p (p) over bar, sigma(e(+)e(-)-> psi(3770) -> p (p) over bar), is found to have two solutions, determined to be (0.059(-0.020)(+0.070) +/- 0.012) pb with the phase angle phi = (255.8(-26.6)(+39.0) +/- 4.8). (< 0.166 pb at the 90% confidence level), or sigma(e(+)e(-) -> psi(3770) -> p<(p)over bar>) = (2.57(-0.13)(+0.12) +/- 0.12) pb with phi = (266.9(-6.3)(+6.1) +/- 0.9)degrees both of which agree with a destructive interference. Using the obtained cross section of psi(3770) -> p (p) over bar, the cross section of p (p) over bar -> psi(3770), which is useful information for the future PANDA experiment, is estimated to be either (9.8(-3.9)(+11.8)) nb (< 27.5 nb at 90% C.L.) or (425.6(-43.7)(+42.9)) nb. (C) 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.
|
|
| 17. |
- Ablikim, M., et al.
(författare)
-
Study of e(+)e(-) -> p(p)over-bar pi(0) in the vicinity of the psi(3770)
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:3, s. 032007-
-
Tidskriftsartikel (refereegranskat)abstract
- The process e(+)e(-) -> p (p) over bar pi(0) has been studied by analyzing data collected at root s = 3.773 GeV, root s = 3.650 GeV, and during a psi(3770) line shape scan with the BESIII detector at the BEPCII collider. The Born cross section of p (p) over bar pi(0) in the vicinity of the psi(3770) is measured, and the Born cross section of psi(3770) -> p (p) over bar pi(0) is extracted considering interference between resonant and continuum production amplitudes. Two solutions with the same probability and a significance of 1.5 sigma are found. The solutions for the Born cross section of psi(3770) -> p (p) over bar pi(0) are 33.8 +/- 1.8 +/- 2.1 pb and 0.06(-0.04-0.01)(+0.10+0.01) pb (< 0.22 pb at a 90% confidence level). Using the estimated cross section and a constant decay amplitude approximation, the cross section sigma(p<(p)over bar> -> psi(3770)pi(0)) is calculated for the kinematic situation of the planned (p) over bar ANDA experiment. The maximum cross section corresponding to the two solutions is expected to be less than 0.79 nb at 90% confidence level and 122 +/- 10 nb at a center-of-mass energy of 5.26 GeV.
|
|
| 18. |
- Ablikim, M., et al.
(författare)
-
Search for the weak decays J/psi -> D-s(()*()-) e(+)nu(e) + c.c.
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:11, s. 112014-
-
Tidskriftsartikel (refereegranskat)abstract
- Using a sample of 2.25 x 10(8) J/psi events collected with the BESIII detector at the BEPCII collider, we search for the J/psi semileptonic weak decay J/psi -> D-s(-) e(+)nu(e) +c.c. with a much higher sensitivity than previous searches. We also perform the first search for J/psi -> D-s(*-) e(+) nu(e) + c.c. No significant excess of a signal above background is observed in either channel. At the 90% confidence level, the upper limits are determined to be B(J/psi -> D-s(-) e(+) nu(e) + c.c.) < 1.3 x 10(-6) and B(J/psi -> D-s*(-) e(+) nu(e) + c.c.) < 1.8 x 10(-6), respectively. Both are consistent with Standard Model predictions.
|
|
| 19. |
- Ablikim, M., et al.
(författare)
-
Search for C-parity violation in J/psi -> gamma gamma and gamma phi
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:9, s. 092002-
-
Tidskriftsartikel (refereegranskat)abstract
- Using 1.06 x 10(8) psi(3686) events recorded in e(+)e(-) collisions at root s = 3.686 GeV with the BESIII at the BEPCII collider, we present searches for C-parity violation in J/psi -> gamma gamma and gamma phi decays via psi(3686) -> J/psi pi(+)pi(-). No significant signals are observed in either channel. Upper limits on the branching fractions are set to be B(J/psi -> gamma gamma) < 2.7 x 10(-7) and B(J/psi -> gamma phi) < 1.4 x 10(-6) at the 90% confidence level. The former is one order of magnitude more stringent than the previous upper limit, and the latter represents the first limit on this decay channel.
|
|
| 20. |
- Ablikim, M., et al.
(författare)
-
Observation of e(+)e(-) -> pi(0)pi(0)h(c) and a Neutral Charmoniumlike Structure Z(c)(4020)(0)
- 2014
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 113:21, s. 212002-
-
Tidskriftsartikel (refereegranskat)abstract
- Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider at center-of-mass energies of root s = 4.23, 4.26, and 4.36 GeV, we observe e(+)e(-) -> pi(0)pi(0)h(c) for the first time. The Born cross sections are measured and found to be about half of those of e(+)e(-) -> pi(+)pi(-)h(c) within less than 2 sigma. In the pi(0)h(c) mass spectrum, a structure at 4.02 GeV/c(2) is found. It is most likely to be the neutral isospin partner of the Z(c)(4020)(+/-) observed in the process of e(+)e(-) -> pi(+)pi(-)h(c) being found. A fit to the pi(0)h(c) invariant mass spectrum, with the width of the Z(c)(4020)(0) fixed to that of its charged isospin partner and possible interferences with non-Z(c)(4020)(0) amplitudes neglected, gives a mass of (4023.9 +/- 2.2 +/- 3.8) MeV/c(2) for the Z(c)(4020)(0), where the first error is statistical and the second systematic.
|
|
| 21. |
- Weinstein, John N., et al.
(författare)
-
The cancer genome atlas pan-cancer analysis project
- 2013
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 45:10, s. 1113-1120
-
Forskningsöversikt (refereegranskat)abstract
- The Cancer Genome Atlas (TCGA) Research Network has profiled and analyzed large numbers of human tumors to discover molecular aberrations at the DNA, RNA, protein and epigenetic levels. The resulting rich data provide a major opportunity to develop an integrated picture of commonalities, differences and emergent themes across tumor lineages. The Pan-Cancer initiative compares the first 12 tumor types profiled by TCGA. Analysis of the molecular aberrations and their functional roles across tumor types will teach us how to extend therapies effective in one cancer type to others with a similar genomic profile. © 2013 Nature America, Inc. All rights reserved.
|
|
| 22. |
- Yang, Geng, et al.
(författare)
-
A Health-IoT Platform Based on the Integration of Intelligent Packaging, Unobtrusive Bio-Sensor, and Intelligent Medicine Box
- 2014
-
Ingår i: IEEE Transactions on Industrial Informatics. - : IEEE. - 1551-3203 .- 1941-0050. ; 10:4, s. 2180-2191
-
Tidskriftsartikel (refereegranskat)abstract
- In-home healthcare services based on the Internet-of-Things (IoT) have great business potential; however, a comprehensive platform is still missing. In this paper, an intelligent home-based platform, the iHome Health-IoT, is proposed and implemented. In particular, the platform involves an open-platform-based intelligent medicine box (iMedBox) with enhanced connectivity and interchangeability for the integration of devices and services; intelligent pharmaceutical packaging (iMedPack) with communication capability enabled by passive radio-frequency identification (RFID) and actuation capability enabled by functional materials; and a flexible and wearable bio-medical sensor device (Bio-Patch) enabled by the state-of-the-art inkjet printing technology and system-on-chip. The proposed platform seamlessly fuses IoT devices (e. g., wearable sensors and intelligent medicine packages) with in-home healthcare services (e. g., telemedicine) for an improved user experience and service efficiency. The feasibility of the implemented iHome Health-IoT platform has been proven in field trials.
|
|
| 23. |
- Li, Jiantong, et al.
(författare)
-
Ink-jet printed thin-film transistors with carbon nanotube channels shaped in long strips
- 2011
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 109:8, s. 084915-
-
Tidskriftsartikel (refereegranskat)abstract
- The present work reports on the development of a class of sophisticated thin-film transistors (TFTs) based on ink-jet printing of pristine single-walled carbon nanotubes (SWCNTs) for the channel formation. The transistors are manufactured on oxidized silicon wafers and flexible plastic substrates at ambient conditions. For this purpose, ink-jet printing techniques are developed with the aim of high-throughput production of SWCNT thin-film channels shaped in long strips. Stable SWCNT inks with proper fluidic characteristics are formulated by polymer addition. The present work unveils, through Monte Carlo simulations and in light of heterogeneous percolation, the underlying physics of the superiority of long-strip channels for SWCNT TFTs. It further predicts the compatibility of such a channel structure with ink-jet printing, taking into account the minimum dimensions achievable by commercially available printers. The printed devices exhibit improved electrical performance and scalability as compared to previously reported ink-jet printed SWCNT TFTs. The present work demonstrates that ink-jet printed SWCNT TFTs of long-strip channels are promising building blocks for flexible electronics.
|
|
| 24. |
- Liu, Zhiying, et al.
(författare)
-
Hysteresis-free thin-film transistors achieved by novel solution-processing of nanotubes/polymer composites
- 2012
-
Ingår i: Materials Research Society Spring Meeting 2012, San Francisco, April 9-13, 2012..
-
Konferensbidrag (refereegranskat)abstract
- Thin-film transistors (TFTs) based on single-walled carbon nanotubes (SWCNTs) have gained enormous attention in the community of flexible/stretchable electronics. At present, such TFTs often suffer from severe problems including giant hysteresis in their transfer characteristics. With SiO2 as the gate dielectric, extensive investigations have led to generally accepted understanding of the hysteresis as being caused by charge transfer between the SWCNTs and their surroundings including both water molecules bound on the SiO2 surface (Si≡OH) and the water/oxygen molecules in the ambient atmosphere. In order to combat the hysteresis issue, significant efforts have been made by annealing the TFTs in vacuum and separating SWCNTs from SiO2 by deposition of a self-assembled monolayer (SAM) on the SiO2 or passivating the SWCNTs with an organic or inorganic dielectric film. These methods, however, require either processing in inert environment or developing elaborated processes. In the present work, we demonstrate hysteresis-free TFTs based on SWCNT/polymer composite without any complex treatment. The composite consists of SWCNTs and poly-9,9_dioctyl-fluorene-co-bithiophene (F8T2). With the aid of polymer F8T2, SWCNTs can be efficiently dissolved in commonly used solvents thereby forming a uniform composite solution. By soaking a chip with predefined TFT structures on an oxidized Si substrate in the composite solution, direct assembly of the composite on the SiO2 occurs, leading to the formation of a composite thin film in the channel region of the TFTs. Although fabricated using a very simple process, our TFTs exhibit hysteresis-free operation under ambient conditions. It is plausible to suggest that SWCNTs are embedded in the F8T2 matrix with the latter providing an effective shield for the former against the trap sites on the SiO2 and the H2O/O2 molecules in the atmosphere. In comparison to the other reported means aiming at hysteresis reduction, the present method is simple, robust, solution processable, effective, and operable under ambient conditions. In addition, we have found F8T2 to preferentially disperse semiconducting SWCNTs rendering a selective removal of the metallic species in the solution. This selectivity is of paramount importance as it results in high-performance TFTs with both high on-state current (0.1 µA/µm @ channel length = 50 µm) and large on/off current ratio (103-105). The TFTs have also shown significantly improved uniformity and dimensional scalability with a mobility value of 10-20 cm2V-1s-1, which have allowed us to investigate the TFTs using the resultant logic circuits.
|
|
| 25. |
- Liu, Zhiying, et al.
(författare)
-
On Gate Capacitance of Nanotube Networks
- 2011
-
Ingår i: IEEE Electron Device Letters. - : IEEE. - 0741-3106 .- 1558-0563. ; 32:5, s. 641-643
-
Tidskriftsartikel (refereegranskat)abstract
- This letter presents a systematic investigation of the gate capacitance C-G of thin-film transistors (TFTs) based on randomly distributed single-walled carbon nanotubes (SWCNTs) in the channel. In order to reduce false counting of SWCNTs that do not contribute to current conduction, C-G is directly measured on the TFTs using a well-established method for MOSFETs. Frequency dispersion of C-G is observed, and it is found to depend on the percolation behavior in SWCNT networks. This dependence can be accounted for using an RC transmission line model. These results are of important implications for the determination of carrier mobility in nanoparticle-based TFTs.
|
|
| 26. |
- Liu, Zhiying, et al.
(författare)
-
Solution-Processable Nanotube/Polymer Composite for High-Performance TFTs
- 2011
-
Ingår i: IEEE Electron Device Letters. - 0741-3106 .- 1558-0563. ; 32:9, s. 1299-1301
-
Tidskriftsartikel (refereegranskat)abstract
- Thin-film field-effect transistors (TFTs) are readily fabricated using a semiconductor composite that is solution processed under ambient conditions for the conduction channel. The composite comprises single-walled carbon nanotubes (SWCNTs) embedded in poly-9,9' dioctyl-fluorene-co-bithiophene. Carrier mobility values approaching 10 cm(2)V(-1)s(-1) are obtained for the composite with relatively high SWCNT concentrations. When the SWCNT concentration is reduced for a large ON/OFF current ratio > 10(6), the mobility remains decent around 0.3 cm(2)V(-1)s(-1). The resultant TFTs display remarkable environmental and operational reliability. Nanotube-based composites are therefore of significance in printed electronics owing to their simplicity in device fabrication and competitiveness in device performance.
|
|
| 27. |
|
|
| 28. |
- Chen, Jian, et al.
(författare)
-
All-digital transmitter based on ADPLL and phase synchronized delta sigma modulator
- 2011
-
Ingår i: Radio Frequency Integrated Circuits Symposium (RFIC), 2011 IEEE. - : IEEE. - 9781424482931 ; , s. 1-4
-
Konferensbidrag (refereegranskat)abstract
- A novel architecture of all-digital polar transmitters is proposed, mainly composed of an all digital PLL (ADPLL) for phase modulation, a 1-bit low-pass delta sigma (ΔΣ) modulator for envelop modulation and a high efficiency class-D PA. The low noise ADPLL and high oversample ΔΣ modulator relax filter design, enabling the use of a on-chip filter. The differential signaling scheme enhances the power of the fundamental tone and suppresses DC and high harmonics. The transmitter was fabricated in a 90nm digital CMOS process, occupying 1.4 mm2. The measurement results demonstrate effectiveness of the architecture. The digital transmitter consumes 58 mW power from a 1 V supply, delivering a 6.81-dBm output.
|
|
| 29. |
- Cho, Yoon Shin, et al.
(författare)
-
Meta-analysis of genome-wide association studies identifies eight new loci for type 2 diabetes in east Asians.
- 2012
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 44:1
-
Tidskriftsartikel (refereegranskat)abstract
- We conducted a three-stage genetic study to identify susceptibility loci for type 2 diabetes (T2D) in east Asian populations. We followed our stage 1 meta-analysis of eight T2D genome-wide association studies (6,952 cases with T2D and 11,865 controls) with a stage 2 in silico replication analysis (5,843 cases and 4,574 controls) and a stage 3 de novo replication analysis (12,284 cases and 13,172 controls). The combined analysis identified eight new T2D loci reaching genome-wide significance, which mapped in or near GLIS3, PEPD, FITM2-R3HDML-HNF4A, KCNK16, MAEA, GCC1-PAX4, PSMD6 and ZFAND3. GLIS3, which is involved in pancreatic beta cell development and insulin gene expression, is known for its association with fasting glucose levels. The evidence of an association with T2D for PEPD and HNF4A has been shown in previous studies. KCNK16 may regulate glucose-dependent insulin secretion in the pancreas. These findings, derived from an east Asian population, provide new perspectives on the etiology of T2D.
|
|
| 30. |
- Feng, Yi, et al.
(författare)
-
Electrical and humidity-sensing characterization of inkjet-printed multi-walled carbon nanotubes for smart packaging
- 2013
-
Ingår i: IEEE SENSORS 2013 - Proceedings. - : IEEE. - 9781467346405 ; , s. 1-4
-
Konferensbidrag (refereegranskat)abstract
- Printing is considered a cost-effective way to fabricate electronics on unconventional substrates enabling, for example, smart packaging. Functionalized multi-walled carbon nanotubes (f-MWCNTs) having carboxylic groups on their surfaces possess great potential as flexible resistive humidity sensor. In this paper, we report on the inkjet printing and characterization of f-MWCNTs in terms of sheet resistance and humidity-sensitivity. Stable f-MWCNTs ink is formulated using aqueous ethylene glycol as solvent. Sheet resistance of printed f-MWCNTs films on polyimide foil reduces by increasing the number of printed layers as well as post-printing annealing temperature. Meanwhile, the raised annealing temperature degrades the films' humidity-sensitivity, which could be explained by the loss of the carboxylic groups. The electrical and sensing properties of f-MWCNTs also have a negative temperature coefficient regarding ambient temperature, which should be considered in practical application.
|
|
| 31. |
- Feng, Yi, et al.
(författare)
-
Fabrication and performance evaluation of ultralow-cost inkjet-printed chipless RFID tags
- 2012
-
Konferensbidrag (refereegranskat)abstract
- This paper studies the performance of inkjet-printed chipless RFID tags based on planar inductor-capacitor resonant circuits. Besides using double-sided printing, a sandwiching process is introduced to fabricate the tags in order to eliminate the need of through-substrate via and match roll-to-roll processing. Due to lower conductivity (~1.25E+7 S/m) and smaller thickness (~1.7μm) of printed conductors with silver nanoparticle ink, the resonant peaks of inkjet-printed tags exhibit around as twice of half-power bandwidth and 60% of maximum reading distance as the etched tags from bulk copper. Nevertheless, the inkjet-printed tag performance is sufficient for many applications, and it can be adjusted and improved by printing and sintering processes.
|
|
| 32. |
- Li, Molan, et al.
(författare)
-
Thermoelectric-Generator-Based DC-DC Conversion Networks for Automotive Applications
- 2011
-
Ingår i: Journal of Electronic Materials. - : Springer Science and Business Media LLC. - 0361-5235 .- 1543-186X. ; 40:5, s. 1136-1143
-
Tidskriftsartikel (refereegranskat)abstract
- Maximizing electrical energy generation through waste heat recovery is one of the modern research questions within automotive applications of thermoelectric (TE) technologies. This paper proposes a novel concept of distributed multisection multilevel DC-DC conversion networks based on thermoelectric generators (TEGs) for automotive applications. The concept incorporates a bottom-up design approach to collect, convert, and manage vehicle waste heat efficiently. Several state-of-the-art thermoelectric materials are analyzed for the purpose of power generation at each waste heat harvesting location on a vehicle. Optimal materials and TE couple configurations are suggested. Moreover, a comparison of prevailing DC-DC conversion techniques was made with respect to applications at each conversion level within the network. Furthermore, higher-level design considerations are discussed according to system specifications. Finally, a case study is performed to compare the performance of the proposed network and a traditional single-stage system. The results show that the proposed network enhances the system conversion efficiency by up to 400%.
|
|
| 33. |
- Liu, Zhiying, et al.
(författare)
-
Mobility Extraction for Nanotube TFTs
- 2011
-
Ingår i: IEEE Electron Device Letters. - 0741-3106 .- 1558-0563. ; 32:7, s. 913-915
-
Tidskriftsartikel (refereegranskat)abstract
- An extensive investigation of carrier mobility is presented for thin-film transistors (TFTs) with single-walled carbon nanotube (SWCNT) networks as the semiconductor channel. For TFTs particularly with low-density SWCNTs in the networks, the extracted mobility using the standard method for Si metal-oxide-semiconductor field-effect transistors is erroneous, mainly resulting from use of a parallel-plate capacitor model and assumption of the source-drain current being inversely proportional to the channel length. Large hysteresis in the transfer characteristics further complicates the extraction. By properly addressing all these challenges in this letter, a comprehensive methodology is established, leading to the extraction of mobility values that are independent of geometrical parameters.
|
|
| 34. |
- Lopez Cabezas, Ana, 1980-, et al.
(författare)
-
Influence of Carbon Nanotubes on Thermal Stability of Water-Dispersible Nanofibrillar Polyaniline/Nanotube Composite
- 2012
-
Ingår i: Materials. - Basel, Switzerland : MDPI AG. - 1996-1944. ; 5:2, s. 327-335
-
Tidskriftsartikel (refereegranskat)abstract
- Significant influence on the thermal stability of polyaniline (PANI) in the presence of multi-walled carbon nanotubes (MWCNTs) is reported. By means of in-situ rapid mixing approach, water-dispersible nanofibrillar PANI and composites, consisting of MWCNTs uniformly coated with PANI in the state of emeraldine salt, with a well-defined core-shell heterogeneous structure, were prepared. The de-protonation process in PANI occurs at a lower temperature under the presence of MWCNTs on the polyaniline composite upon thermal treatment. However, it is found that the presence of MWCNTs significantly enhances the thermal stability of PANI's backbone upon exposure to laser irradiation, which can be ascribed to the core-shell heterogeneous structure of the composite of MWCNTs and PANI, and the high thermal conductivity of MWCNTs.
|
|
| 35. |
- Lopez Cabezas, Ana, et al.
(författare)
-
Morphological development of nanofibrillar composites of polyaniline and carbon nanotubes
- 2010
-
Ingår i: Synthetic metals. - : Elsevier BV. - 0379-6779 .- 1879-3290. ; 160:7-8, s. 664-668
-
Tidskriftsartikel (refereegranskat)abstract
- Nanofibrillar composite of polyaniline (PANI)/multi-walled carbon nanotubes (MWNTs) is readily synthesized by means of conventional in situ polymerization process. It is found that the MWNT loading during polymerization has a significant influence on both the micro- and macro-scale morphological properties of the composites. At low MWNT loadings, PANI/MWNTs are formed as individual nanofibers, similar to that of the neat PANI in the absence of MWNTs. With the increase in MWNT loading, the composite exhibits granular form and becomes a continuous porous matrix at higher MWNT loadings. A possible mechanism is proposed to account for the structural variation of the composites caused by MWNTs at the different loadings.
|
|
| 36. |
- Lopez Cabezas, Ana, 1980-
(författare)
-
Nanofibrillar Materials for Organic and Printable Electronics
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In recent years, organic electronics have attracted great attention due to their multiple advantages such as light weight, flexibility, large area fabrication and cost-effective production processes. The recent progress in fabricating organic electronic devices has been achieved with the development of new materials which provide competing functionalities to the electronics devices. However, as it happens with all type of technologies, organic electronics is not free from challenges. In the latest OE-A Roadmap for organic and printed electronics (2011), the “red brick walls” were identified, and the following three main challenges were pointed out as the potential roadblocks from the material point of view: electrical performance, solution processability (especially formulations in non-toxic solvents) and environmental stability. Currently there is a significant increasing interest in optimizing or developing novel materials to meet those requirements. This thesis presents processing development and study of nanofibrillar materials and deals with the optimization for its applicability for organic electronics. The overall work presented in the thesis is based on three nanofibrillar materials: Polyaniline (PANI), carbon nanotubes (CNTs) and the CNT/PANI composite. First, the solution processability of carbon nanotubes and polyaniline is studied respectively, and through covalent and non-covalent methods, stable aqueous dispersions of these materials are successfully achieved. Second, a composite consisting of multi-walled carbon nanotubes (MWCNTs) and PANI with a core-shell structure is developed and characterized. The investigation of the effects of the loading and type of nanotubes incorporated in the composite material, led to understanding on the fundamental theory underlying the composite morphology. Based on those findings and by carefully optimizing the synthesis procedure, water dispersible MWCNT/PANI nanofibrillar composite is successfully synthesized becoming compatible with solution processable techniques, such as spray coating and potentially with printing technology. With the incorporation of carbon nanotubes, the nanofibrillar composite reaches conductivities 20 times higher than that of the pure polymer. Moreover, the presence of the nanotubes in the composite material decelerates up to 60 times the thermal ageing of its conductivity, making the polymer more robust and suitable for possible manufacturing processes. Furthermore, the composite material still retains the advantageous properties of PANI: electrochromism, tunable conductivities, and sensing capabilities. Third, the stable dispersions of PANI, CNTs and MWCNT/PANI composite were effectively deposited by spray coating technique on several low-cost substrates (PET, PEN, polyimide and papers), and homogeneous, flexible, large-area films were fabricated. Additionally, by spraying the materials on pre-fabricated inkjet printed electrodes, a pH sensor based on the MWCNT/PANI composite and a humidity sensor based on functionalized MWCNTs capable of working at GHz range were demonstrated, which shows that the nanofibrillar materials studied in this thesis work are promising sensor materials for wireless application at ultra-high frequency (UHF) band. Finally, the humidity sensor was integrated into a sensor-box demonstrating a hybrid interconnection platform where printed electronics can be seamlessly integrated with silicon-based electronics. The integration closes the gap between the two technologies, anticipating the adaption of organic electronic technologies.
|
|
| 37. |
- Mäntysalo, Matti, et al.
(författare)
-
System integration of smart packages using printed electronics
- 2012
-
Ingår i: Electronic Components and Technology Conference (ECTC), 2012 IEEE 62nd. - : IEEE. - 9781467319669 ; , s. 997-1002
-
Konferensbidrag (refereegranskat)abstract
- The last decade has shown enormous interest in additive and printed electronics manufacturing technologies, especially in intelligent packaging. Scientists and engineers all over the world are developing printed organic circuits. Despite their effort, the performance and yield of all-printed devices cannot replace silicon-based devices in smart package applications. Therefore, we have developed a hybrid interconnection platform to seamlessly integrate printed electronics with silicon-based electronics, close the gap between the two technologies, and to anticipate adaption of printed electronic technologies. We studied the suitability of a printed interconnection platform by fabricating a printed sensor-box that contains printed nano-Ag-interconnections on low-temperature plastic, a printable humidity sensor based on functionalized MWCNTs, a printed battery, conventional SMDs, and a silicon-based MCU.
|
|
| 38. |
- Rong, Liang, 1981-, et al.
(författare)
-
A 11.4dBm 90nm CMOS H-Bridge Resonating Polar Amplifier using RF Sigma Delta Modulation
- 2011
-
Ingår i: Proceedings of the ESSCIRC (ESSCIRC), 2011. - : IEEE. - 9781457707032 ; , s. 307-310
-
Konferensbidrag (refereegranskat)abstract
- Using RF Sigma Delta Modulation (RFSDM), aclass-D polar amplifier in H-Bridge configuration can work in resonatingmode and minimize the switching loss for high efficiencypolar transmitters. The high oversampling ratio envelop bitstream created by the low pass RFSDM is phase modulated anddigitally mixed with quantized RF carrier to give a modulatedRF digital signal. By taking the advantage of high speed andaccurate digital CMOS process, this ’information combination’architecture can achieve high efficiency and reduce the need forexternal filter components. A polar power amplifier based on thisconcept is implemented in 90nm CMOS process and achieved apeak output power of 11.4dBm with 19.3% efficiency at 1.0Vpower supply. The total area is 0.72mm2 including an on-chipfilter matching network designed for 2.4GHz to 2.7GHz band.
|
|
| 39. |
- Rong, Liang, 1981-, et al.
(författare)
-
A polar transmitter architecture with digital switching amplifier for UHF RFID applications
- 2011
-
Ingår i: 5th Annual IEEE International Conference on RFID. - : IEEE. - 9781424496075 ; , s. 1-6
-
Konferensbidrag (refereegranskat)abstract
- With amplitude shift keying (ASK) modulation and signal envelope rising falling edge slope requirements, the efficiency of UHF RFID system can be improved by using polar transmitter architecture than using linear power amplifiers. In this work, to ensure maximum integration and meet EPC Class-1 Generation-2 specification, an all digital polar transmitter is proposed and verified by transient signal analysis and random pattern simulation. The timing and signal quality constraints of the digital polar transmitter circuits are extracted. Due to the use of RF frequency low pass sigma delta modulation, the system can be designed in pure digital process without on-chip inductive components. Compared to the 31% theoretical efficiency by using class-A linear power amplifier, a minimum 77% theoretical efficiency can be achieved in this proposed digital RFID system.
|
|
| 40. |
- Rong, Liang, et al.
(författare)
-
A Switch Mode Resonating H-Bridge Polar Transmitter using RF Sigma Delta Modulation
- 2010
-
Ingår i: IEEE INT SYMP CIRC SYST PROC. - 9781424453092 ; , s. 1911-1914
-
Konferensbidrag (refereegranskat)abstract
- Using saturated power amplifier (PA) as the last stage, polar transmitter has the potential to be the most power efficient architecture to transmit large Peak-to-Average Ratio (PAR) signals. In this work, a polar transmitter using H-Bridge configured Class-D amplifiers is proposed. To fully exploit low voltage resource, maintain linearity and meet the spectrum mask requirements, RF Sigma-Delta Modulation (SDM) is used. An on-chip transformer based filter network is designed to filter out SDM noise and provide load matching. The system verification is carried out by using Matlab passband simulation on a 13dB PAR mobile WiMAX signal. Evaluation of noise shaping and spectral regrowth shows the proposed architecture can achieve -45dBc/10kHz ACPR in a 140MHz bandwidth range. This provides a solid ground for the circuit design work.
|
|
| 41. |
- Rong, Liang, 1981-
(författare)
-
All Digital Polar Transmitter Design for Software Defined Radio : Architecture and Low Power Circuit Implementation
- 2012
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The evolving wireless communication technology is aiming highdata rate, high mobility, long distance and at the meantime, co-existwith various different standards. This developing trend requires ahighly linear transceiver system and it causes the problem of lowefficiency due to the large crest factor of signals. On the other hand,with process scaling, digital blocks are occupying more functions andchip area than before, to fully utilize the digital process low poweradvantage and save design cost, hardware reuse is preferable. Theconcept of Software Defined Radio (SDR) is raised to make thesystem more adaptable to multiple communication standards withminimal hardware resources.In this doctoral dissertation work, the software defined radioarchitecture especially the all-digital polar transmitter architecture isexplored. System level comparison on different transmitter topologiesis carried out in the first place. Direct conversion, out-phasing andpolar transmitter topologies are compared. Based on the system levelevaluation, a Lowpass Sigma Delta Modulation (LPSDM) digitalpolar transmitter is designed under 90nm CMOS process andpackaged in QFN32. 19.3% peak efficiency and 11.4dBm outputpower is measured under single 1.0V supply. The constellationmeasurement achieved 5.08% for 3pi/8PSK modulation and 7.01%for QAM16 modulation output. The measurement on the packagedtransmitter AM/AM and AM/PM also demonstrated the linearity andpower efficiency performance under low voltage environment. This verified the possibility for a fully SDR solution in the future.As a specific application and genuine creation, the UHF RFIDstandard is mapped into digital polar transmitter architecture. System level simulation is performed and transient signal parameters areextracted. To prove the SDR possibility, the system is fully designedby VHDL language and downloaded into FPGA hardware with highspeed serial port. The measured results confirm the possibility of thedigital polar transmitter architecture potential in SDR systemrealization.Based on the design and verification of two different systems, themethodology for digital implementation of linear transmitter systemis developed and the skill to carry out optimization and measurementis also possessed. In conclusion, the academic publication andverification proved the feasibility of digital polar transmitterapplication in linear system and point out the direction for a fullySDR realization.
|
|
| 42. |
- Xie, Li, et al.
(författare)
-
A system-on-chip and paper-based inkjet printed electrodes for a hybrid wearable bio-sensing system
- 2012
-
Ingår i: Engineering in Medicine and Biology Society (EMBC), 2012 Annual International Conference of the IEEE. - : IEEE. - 9781424441198 ; , s. 5026-5029
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a hybrid wearable bio-sensing system, which combines traditional small-area low-power and high-performance System-on-Chip (SoC), flexible paper substrate and cost-effective Printed Electronics. Differential bio-signals are measured, digitized, stored and transmitted by the SoC. The total area of the chip is 1.5 × 3.0 mm2. This enables the miniaturization of the wearable system. The electrodes and interconnects are inkjet printed on paper substrate and the performance is verified in in-vivo tests. The quality of electrocardiogram signal sensed by printed electrodes is comparable with commercial electrodes, with noise level slightly increased. The paper-based inkjet printed system is flexible, light and thin, which makes the final system comfortable for end-users. The hybrid bio-sensing system offers a potential solution to the next generation wearable healthcare technology.
|
|
| 43. |
- Xie, Li, et al.
(författare)
-
Electrical performance and reliability evaluation of inkjet-printed Ag interconnections on paper substrates
- 2012
-
Ingår i: Materials letters (General ed.). - : Elsevier BV. - 0167-577X .- 1873-4979. ; 88, s. 68-72
-
Tidskriftsartikel (refereegranskat)abstract
- Printing technology, especially inkjet printing, enables mass manufacturing of electronics on various substrate materials. Paper is one potential carrier for printed electronics to realize low-cost, flexible, recyclable smart packages. However, concerns exist regarding commonly used photo paper substrate, in terms of price and reliability against environmental variation. In this work, for the first time, ordinary low-cost and high-moisture-resistance package paper is investigated as an alternative to be the substrate of printed electronics. The surface morphology and electrical performance of inkjet printed interconnections on six different paper substrates from two categories (inkjet paper and package paper) are examined and compared. The printed interconnections on inkjet papers show smaller sheet resistance and better repeatability than those on package papers. However, low-cost package paper stands higher temperature and exhibits better reliability during 85°C/85 RH aging test. Package paper is suitable for smart package applications that have relaxed requirements of conductivity and high requests of moisture resistance.
|
|
| 44. |
- Xie, Li, et al.
(författare)
-
Heterogeneous integration of bio-sensing system-on-chip and printed electronics
- 2012
-
Ingår i: IEEE Journal on Emerging and Selected Topics in Circuits and Systems. - 2156-3357 .- 2156-3365. ; 2:4, s. 672-682
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present a heterogeneous integration platform for bio-sensing applications, which seamlessly integrates low-power silicon-based circuits with cost-effective printed electronics. A prototype of wearable Bio-Sensing Node is fabricated to investigate the suitability of this integration approach. A customized mixed-signal system-on-chip (SoC) with the size of 1.5× 3.0 mm2 is utilized to amplify, digitize, buffer, and transmit the sensed bio-signals. Inkjet printing technology is employed to print nano-particle silver ink on a flexible substrate to fabricate chip-on-flex, electrodes as well as interconnections. This additive and digital fabrication technology enables fast prototype of the customized electrode pattern. Its high accuracy and fine resolution features allow the direct integration of the bare die (the pad size of 65 μ m and pitch size of 90 μ m) on the flexible substrate, which significantly miniaturizes the wearable system. The optimal size and layout of printed electrodes are investigated through the in vivo test for electrocardiogram recording applications. The total size of the implemented Bio-Sensing Node is 4.5× 2.5 cm2, which is comparable with a commercial electrode. This inkjet printed heterogeneous integration approach offers a promising solution for the next-generation cost-effective personalized wearable healthcare monitoring devices.
|
|
| 45. |
- Xie, Li, et al.
(författare)
-
Integration of f-MWCNT Sensor and Printed Circuits on Paper Substrate
- 2013
-
Ingår i: IEEE Sensors Journal. - 1530-437X .- 1558-1748. ; 13:10, s. 3948-3956
-
Tidskriftsartikel (refereegranskat)abstract
- The integration of sensors endows the packages with intelligence and interactivity. This paper is considered the most suitable substrate of smart packages because it is cost-effective, light, flexible, and recyclable. However, common concern exists regarding the reliability of paper-based system against bending and folding. In this paper, inkjet-printing of silver nanoparticles is used to form circuit pattern as well as interconnections for system integration on paper substrate. A humidity sensor made by functionalized multiwalled carbon nanotubes is fabricated on the same substrate. We evaluate the electrical performance of paper electronics and the reliability against bending and folding. The results reveal the capability and the limitation of paper electronics in terms of flexibility. The concept of a paper-based smart electronic system and the manufacture process are demonstrated by an interactive humidity sensor card prototype.
|
|
| 46. |
- Yang, Geng, 1980-, et al.
(författare)
-
A Hybrid Low Power Biopatch for Body Surface Potential Measurement
- 2013
-
Ingår i: IEEE Journal of Biomedical and Health Informatics. - : IEEE Computer Society. - 2168-2194. ; 17:3, s. 591-599
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents a wearable biopatch prototype for body surface potential measurement. It combines three key technologies, including mixed-signal system on chip (SoC) technology, inkjet printing technology, and anisotropic conductive adhesive (ACA) bonding technology. An integral part of the biopatch is a low-power low-noise SoC. The SoC contains a tunable analog front end, a successive approximation register analog-to-digital converter, and a reconfigurable digital controller. The electrodes, interconnections, and interposer are implemented by inkjet-printing the silver ink precisely on a flexible substrate. The reliability of printed traces is evaluated by static bending tests. ACA is used to attach the SoC to the printed structures and form the flexible hybrid system. The biopatch prototype is light and thin with a physical size of 16 cm x 16 cm. Measurement results show that low-noise concurrent electrocardiogram signals from eight chest points have been successfully recorded using the implemented biopatch.
|
|
| 47. |
- Yang, Geng, et al.
(författare)
-
Bio-Patch Design and Implementation Based on a Low-Power System-on-Chip and Paper-Based Inkjet Printing Technology
- 2012
-
Ingår i: IEEE transactions on information technology in biomedicine. - 1089-7771 .- 1558-0032. ; 16:6, s. 1043-1050
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents the prototype implementation of a Bio-Patch using fully integrated low-power System-on-Chip (SoC) sensor and paper-based inkjet printing technology. The SoC sensor is featured with programmable gain and bandwidth to accommodate a variety of bio-signals. It is fabricated in a 0.18-µm standard CMOS technology, with a total power consumption of 20 µW from a 1.2 V supply. Both the electrodes and interconnections are implemented by printing conductive nano-particle inks on a flexible photo paper substrate using inkjet printing technology. A Bio-Patch prototype is developed by integrating the SoC sensor, a soft battery, printed electrodes and interconnections on a photo paper substrate. The Bio-Patch can work alone or operate along with other patches to establish a wired network for synchronous multiple-channel bio-signals recording. The measurement results show that electrocardiogram and electromyogram are successfully measured in in-vivo tests using the implemented Bio-Patch prototype.
|
|
| 48. |
- Ahmad, Waqar, et al.
(författare)
-
Modeling of peak-to-peak core switching noise, output impedance, and decoupling capacitance along a vertical chain of power distribution TSV pairs
- 2012
-
Ingår i: Analog Integrated Circuits and Signal Processing. - : Springer Science and Business Media LLC. - 0925-1030 .- 1573-1979. ; 73:1, s. 311-328
-
Tidskriftsartikel (refereegranskat)abstract
- In this article we propose an efficient and accurate model to estimate peak-to-peak core switching noise, caused by simultaneous switching of logic loads along a vertical chain of power distribution TSV pairs in a 3D stack of dies interconnected through TSVs. The proposed model is accurate with only a 2–3% difference in peak-to-peak core switching noise as compared to the Ansoft Nexxim4.1 equivalent model. The proposed model is 3–4 times faster than Ansoft Nexxim4.1 and uses two times less memory as compared to the Ansoft Nexxim4.1 equivalent model. In this article we also thoroughly establish design guidelines for almost flat output impedance magnitude at each stage of a vertical chain of power distribution TSV pairs to realize a resonance free scenario over a wide operating frequency range. We also establish decoupling capacitance design guidelines based on the optimum output impedance and critically damped supply voltage for the core logic for each stage of a vertical chain of power distribution TSV pairs.
|
|
| 49. |
- Ahmad, Waqar, et al.
(författare)
-
Modeling of peak-to-peak switching noise along a vertical chain of power distribution TSV pairs in a 3D stack of ICs interconnected through TSVs
- 2010
-
Ingår i: 28th Norchip Conference, NORCHIP 2010.
-
Konferensbidrag (refereegranskat)abstract
- On-chip power supply noise has become a bottleneck in 3D ICs as scaling of the supply network impedance has not been kept up with increasing device densities and operating currents with each technology node due to limited wire resources. In this paper we proposed an efficient and accurate model to estimate peak-to-peak switching noise, caused by simultaneous switching of logic loads along a vertical chain of power distribution TSV pairs in a 3D stack of ICs. The proposed model is quite accurate with only 2-3% difference from Ansoft Nexxim4.1 equivalent model. The proposed model is 3-4 times faster than Nexxim4.1 as well as consumes two times less memory as compared to Nexxim4.1equivalent model. We analyzed peak-to-peak switching noise along a vertical chain of power distribution TSV pairs by varying physical dimensions of TSVs and value of decoupling capacitance. We also thoroughly investigated the peak-to-peak noise sensitivity to TSV effective inductance and decoupling capacitance.
|
|
| 50. |
- Ahmad, Waqar, et al.
(författare)
-
Peak-to-Peak Ground Noise on a Power Distribution TSV Pair as a Function of Rise Time in 3-D Stack of Dies Interconnected Through TSVs
- 2011
-
Ingår i: IEEE Transactions on Components Packaging and Manufacturing Technology. - 2156-3950. ; 1:2, s. 196-207
-
Tidskriftsartikel (refereegranskat)abstract
- Supply grids of integrated chips are interconnected through through-silicon vias (TSVs) in modern design techniques to form a 3-D stack in vertical direction. The load on each chip is supplied through (power/ground) TSV pairs. Accurate estimation of power/ground noise on each TSV pair of a 3-D power distribution network is necessary for a robust power supply design. The worst case noise obtained with fast switching characteristics may not be significantly accurate. The behavior of power/ground noise as a function of rise time for an inductive power distribution TSV pair with decoupling capacitance, is investigated in this paper. An equivalent rise time corresponding to resonance is presented to accurately estimate the worst case power/ground noise in the time domain. In addition noise sensitivity to decoupling capacitance and TSV inductance is evaluated as a function of rise time. We also discuss noise accumulation as a result of worst case damping factor in this paper.
|
|
