| 1. |
- Ahlin, Lars, et al.
(författare)
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Automous Tactical Communications Possibilities and Problems
- 1997
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Ingår i: MILCOM 97 Proceedings. - 0780342496 ; , s. 393-397
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Konferensbidrag (refereegranskat)abstract
- In the battlefield of the future, more and more information will be available for making decisions on a tactical level, provided that this information can be dispersed rapidly and accurately. As a consequence, advanced tactical decision support that now is limited to advanced platforms (e.g. combat aircrafts) will become available at a much lower level, ranging from different kinds of vehicles, down to the individual soldier by means of ultra-light weight ``wearable'' equipment. Establishing reliable wireless communications in such a large group of users with unprecidented bandwidth demands and requirements on survivability constitutes a considerable enginerring challenge. In the paper we will, after a short review of some existing approaches, investigate the specific engineering challenges and the fundamental limitations of such low level, autonomous communication systems. Further we give an example of a system architecture, harmonized with a proposed structure for third generation commercial wireless systems (e.g. UMTS). Our conclusions show that mainly distributed computing complexity, device power consumption and available bandwidth constitute the fundamental problems.
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| 2. |
- Anand-Ivell, Ravinder, et al.
(författare)
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Amniotic fluid INSL3 measured during the critical time window in human pregnancy relates to cryptorchidism, hypospadias, and phthalate load : A large case-control study
- 2018
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Ingår i: Frontiers in Physiology. - : Frontiers Media SA. - 1664-042X. ; 9:APR
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Tidskriftsartikel (refereegranskat)abstract
- The period of the first to second trimester transition in human pregnancy represents a sensitive window for fetal organogenesis, particularly in regard to the development of the male reproductive system. This is a time of relative analytical inaccessibility. We have used a large national biobank of amniotic fluid samples collected at routine amniocentesis to determine the impacts of exogenous endocrine disruptor load on specific fetal biomarkers at this critical time. While adrenal and testicular steroids are highly correlated, they are also mostly positively influenced by increasing phthalate load, represented by the metabolites 7cx-MMeHP and 5cx-MEPP, by perfluorooctane sulfonate (PFOS) exposure, and by smoking, suggesting an adrenal stress response. In contrast, the testis specific biomarkers insulin-like peptide 3 (INSL3) and androstenedione are negatively impacted by the phthalate endocrine disruptors. Using a case-control design, we show that cryptorchidism and hypospadias are both significantly associated with increased amniotic concentration of INSL3 during gestational weeks 13-16, and some, though not all steroid biomarkers. Cases are also linked to a specifically increased variance in the Leydig cell biomarker INSL3 compared to controls, an effect exacerbated by maternal smoking. No influence of phthalate metabolites or PFOS was evident on the distribution of cases and controls. Considering that several animal and human studies have shown a negative impact of phthalate load on fetal and cord blood INSL3, respectively, the present results suggest that such endocrine disruptors may rather be altering the relative dynamics of testicular development and consequent hormone production, leading to a desynchronization of tissue organization during fetal development. Being born small for gestational age appears not to impact on the testicular biomarker INSL3 in second trimester amniotic fluid.
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| 3. |
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| 4. |
- Andreucci, Alessandro, et al.
(författare)
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Cadmium may impair prostate function as measured by Prostate Specific Antigen in semen: a cross-sectional study among European and Inuit men.
- 2015
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Ingår i: Reproductive Toxicology. - : Elsevier BV. - 1873-1708 .- 0890-6238. ; 53:Feb 3, s. 33-38
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the association between cadmium in blood and the concentration of the prostate specific antigen (PSA) in semen, including the modifying effects of zinc or the CAG polymorphism in the androgen receptor (AR). Blood and semen samples were collected from 504 partners of pregnant women in Greenland, Poland and Ukraine. We found an inverse trend between cadmium and PSA (log (ß)= -0.121, 95% Confidence Interval (CI):-0.213; -0.029, P=0.0103) in Greenlandic men. Similar results were observed in men with a high number of CAG repeats (CAG 24) (log (ß)=-0.231, 95% CI:-0.363; -0.098, P=0.0009). Inverse trends between cadmium and PSA were found when semen zinc concentrations were below the median value for men from Ukraine and Greenland. These outcomes suggest that cadmium may impair prostate function, as measured by PSA in semen, while high zinc levels and a low number of CAG repeats protects against this action.
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| 5. |
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| 6. |
- Bathelt, Jens, et al.
(författare)
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Conceptual Design Approach For Mechatronic Systems Controlled by a Programmable Logic Controller (PLC)
- 2003
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Konferensbidrag (refereegranskat)abstract
- Traditionally, the development of mechatronic systems starts with the mechanical design. Later electronic components and program logic for the product are added. This work proposes an improved interdisciplinary concurrent product development process with an enhanced function structure for the conceptual design phase. The new methodology is based on the German guideline VDI 2221 [1]. Transition conditions, time aspects and logic flow are added to the normal function structure. An example shows how to use the improved function structure. The enhanced function structure is used to derive the initial logic for the development of the PLC program controlling the machine later on. Since the extended function structure also covers the traditional information, it can still be used when building the assembly tree. By adding more information in the neutral function structure, the same information can be used for the mechanical design as well as for the electronic and logical design. The interdisciplinary communication and documentation among the engineers will be improved and errors in the concept will be detected earlier.
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| 7. |
- Bathelt, Jens, et al.
(författare)
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How to Implement the Virtual Machine Concept Using xPC Target
- 2003
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Konferensbidrag (refereegranskat)abstract
- This paper presents an overview of the historical background of the virtual machine, containing a real control, a machine simulation and a 3D machine visualisation. This setup enables realistic system simulations, since the simulation input comes from a real control. The first known implementation of the virtual machine using xPC Target is described with an existing water jet cutting machine as an example. MathWorks products offer all necessary software for the presented setup, except the interface for the actual speed value from the simulated incremental encoder to the control. The unique xPC driver implementation, as a noninlined C-MEX S-Function, is presented at the end of this paper. The successful implementation of the virtual machine demonstrates the feasibility of the presented approach.
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| 8. |
- Bathelt, Jens, et al.
(författare)
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Modularisierung SPS-gesteuerter mechatronischer Systeme
- 2003
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Konferensbidrag (refereegranskat)abstract
- Rein mechanische Lösungen werden zunehmend von mechatronischen Systemen abgelöst. Der X-by-wire Ansatz zeigt auch, dass der Anteil an mechanischen Teillösungen eines mechatronischen Systems immer weiter zurückgeht. Der vorliegende Beitrag skizziert einen Entwicklungsprozess für SPS-gesteuerte mechatronische Systeme, der dem immer wichtiger werdenden Steuerungsanteil Rechnung trägt. Dabei steht das parallele Arbeiten der Steuerungstechnik und der Konstruktion im Vordergrund, um die Entwicklungszeiten zu verkürzen und Fehler früher zu erkennen. Realisiert wird dies durch eine fachspezifische Modularisierung, deren erste Modulhierarchie als Ausgangslage der jeweiligen Disziplinen fungiert und somit einen parallelen Start ermöglicht. In dieser Arbeit werden Regeln vorgestellt, um die fachspezifischen Module von einer Funktionsstruktur abzuleiten. Abschliessend wird das Vorgehen anhand eines Industriebeispieles erläutert.
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| 9. |
- Berggren, Fredrik, et al.
(författare)
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Dynamic Spectrum Access, Phase 1 Scenarios and research challenges
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The currently used mechanisms for spectrum management are a contributing factor to the long lead times from innovation to market in wireless technologies andsystems. This has in turn been a major contributing factor to the dominance of the large telecom companies in the European and World markets, whereas very few innovative enterprises have exhibited consistent growth, although the technicalcompetence in Sweden is very high in this area. Alternative spectrum management regimes, such as the introduction of "unlicensed bands" have proven very effective in lowering entry thresholds for smaller companies (e.g the WLAN business). In addition, experts claim that the spectrum requirements for communication purposes will increase by as much as 200-300 % up to 2010. At the same time the actual usage of the electromagnetic spectrum is very inefficient.The project aims at studying new more, flexible, spectrum allocation regimeswhich, in combination with new technologies, such as multi-radio access, novelbroadband access techniques, software defined radio and spatial techniques (e.g.smart antennas, multi-hop schemes) have the potential of lowering the entry thresholds for new actors and provide radical improvement to the efficiency ofspectrum usage. Further the aim is to investigate the economic and regulatory consequences of such Dynamic Spectrum Access technologies and managementregimes. The results will provide input to future policies in spectrum management. The project has been divided into a first, pre-study phase and a second, research phase. The first phase was launched in Dec of 2004 and the second phase is planned to start in Jan 2005. The first phase of the project, reported here, has the aim toprovide a qualitative assessment of the potential benefits of dynamic spectrum access regimes. The analysis in the report and other studies in the area, indeed indicate there is a potential to both lower the entry thresholds for new actors as well as provide radical improvement to the efficiency of spectrum usage. The area isdefinitely of significant issues and the project should be continued studying the DSA concepts in more detail.Further, using a systematic procedure, a number of critical areas and bottleneck problems were identified. Our conclusion is that more research is needed in theseareas to achieve the above mentioned benefits. As `side effect' in this procedure, a number of novel and interesting spectrum management concepts were derived, e.g.the `real-time spectrum trading' and `use rights' concepts. Out of this gross list ofinterest problems, a number of highly important problems were selected, matching the competence of the project team. These problems are proposed to be the focus ofthe next phase in the project.Finally, the report provides an overview of the most important ongoing research and policy-making activities in the DSA-area.
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