| 1. |
- Liwång, Hans, 1974, et al.
(författare)
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Quantitative risk analysis – Ship security analysis for effective risk control options
- 2013
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Ingår i: Safety Science. - : Elsevier BV. - 0925-7535 .- 1879-1042. ; 58:1, s. 98-112
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Tidskriftsartikel (refereegranskat)abstract
- This study reviews ship security assessment. The objectives are to explore the possibilities for quantifying and performing a more thorough ship security risk analysis than that described in the International Ship and Port Facility Security code and to evaluate to what extent this more detailed analysis increases ship security and facilitate the effective selection of risk control options.The study focuses on Somali-based maritime piracy, using piracy on the Indian Ocean as a case study. Data are collected using questionnaires and interviews with civilian and military security experts who possess firsthand experience of piracy off the coast of Somalia. The data are collected specifically for this study and describe and quantify the threat’s capability, intent and likelihood of exploiting a ship’s vulnerability. Based on the collected description of the threat, the study analyzes and describes: probability of detection by pirates, probability of successful approach, and probability of successful boarding.The performed work shows good agreement between calculated probabilities and frequencies in the cited incident reports. Also, the developed scenarios describe the most important influences on the analysed areas. The research therefore shows that the proposed risk-based approach, which uses structurally collected and documented information on the threat, can increase ship security by assisting in selecting risk control options. The approach also allows for a better understanding of the causal relationship between threat and risk than that provided in today’s security analysis by ship owners, for example. This understanding is crucial to choosing effective and robust risk control options.
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| 2. |
- Liwång, Hans, 1974-, et al.
(författare)
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Ship security analysis : the effect of ship speed and effective lookout
- 2013
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Ingår i: Proceedings of the ASME 32nd International Conference on Ocean, Offshore and Arctic Engineering (OMAE 2013). - : ASME Press. - 9780791855324
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Konferensbidrag (refereegranskat)abstract
- The threat of piracy to commercial shipping is a concern for the protection and safeguarding of human lives, property and environment. Therefore, ships under piracy threat should follow security measures suggested by the International Maritime Organization (IMO) and the Contact Group on Piracy off the Coast of Somali. It is, therefore, important to choose the proper security measures for the right situation.This study presents a simulation model that can be used for probabilistic risk assessments regarding the operation of commercial ships. This investigation specifically studies the pirate approach phase and quantifies the effect of ship speed and effective lookout. The purpose of introducing probabilistic risk assessment into the analysis of pirate attacks is to meet safety goals more effectively through a well-balanced combination of proactive and reactive measures whilst keeping focus on the intended over all purpose of the particular ship.The study presents collected and documented knowledge regarding pirate capability, intention and likelihood to perform attacks. The knowledge is collected from experts with experience from the situation off the Horn of Africa. The collected information is input to an influence analysis that identifies the network of influences that govern the skiff approach. The simulation model describes piracy characteristics and decision making on the threatened ship, the characteristics and countermeasures of the ship under attack, as well as weather.Based on a comparison with available statistics the overall conclusion of the work is that the threat analysis and the simulation model can quantify and explain how the studied risk control options affect the probability of a successful approach. The result therefore exemplifies how a quantified ship security analysis can support the recommendations in industry guidelines and also enable recommendations that to a greater extent can facilitate an educated decision by the ship operators.
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| 3. |
- Liwång, Hans, et al.
(författare)
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Ship security challenges in high-risk areas : manageable or insurmountable?
- 2015
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Ingår i: WMU Journal of Maritime Affairs (JoMA). - : Springer Berlin/Heidelberg. - 1651-436X .- 1654-1642. ; 14:2, s. 201-217
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Tidskriftsartikel (refereegranskat)abstract
- Piracy can lead to risks so high that they, according to the International Maritime Organization, are tolerable only if risk reduction is not practicable or is disproportionate to the benefits achieved. Therefore, there is a need for reducing ship security risks in relation to antagonistic threats such as piracy. The aim of this study is to identify challenges for ship operators when developing their ship security management. Furthermore, this study also investigates two central aspects in the analysis: understanding the threat and understanding how a security threat affects the crew and operation of the ship. It is clear from the analysis that the importance of subjective aspects beyond a ship operators’ direct control is high. This seems to be the fact for all aspects of the risk management process. The situation is also dynamic as the security risk, as well as the risk perception, can change dramatically even though there are no actual operational changes. As a result, the ship security management process is highly iterative and depends on situations on board as well as conditions out of the ship operator’s control. In order to make ship security manageable, the risk management has to put particular focus on methodological understanding, relevant system understanding and well-defined risk acceptance criteria as well as on including all levels of the organization in the risk reduction implementation and on a continuous monitoring.
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| 4. |
- Liwång, Hans, 1974-
(författare)
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Risk-based ship security analysis – an approach based on civilian and military methods
- 2012
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The demands on maritime operations today are increasingly higher in terms of control, efficiency and cost. The margins for accidents and security incidents are therefore decreasing. In the area of ship safety the regulations, guidelines and methods have a history and culture of systematic research, development and implementation. In contrast, international security is highly politicized and therefore not as transparent. The result is that a tradition of ship security is not as well established.The overall aim of this thesis is to propose a method for ship security analysis that increases the overall safety of the crew and the ship. The objective is to develop a method that is systematic in order to ensure that assessment and response are complete and effective, and that the process is documented to provide evidence of decision-making.The method used is probabilistic risk assessment where quantitative analysis is central. The proposed approach is consistent with the requirements of maritime safety work. However, in the work here, the proposed methods are specifically tested for security cases. This is because hazards (without intent) and threats (with intent) evolve in different ways into risk. Therefore, they must be analysed differently in order to capture the causal relationship.The proposed approach consists of three steps: the first step consists of a threat description that documents qualitative and quantitative aspects that together describe how the threat most likely will act in relation to the ship’s vulnerability; the second step uses the threat description to define the system studied as well as the scenarios that collectively describe the harmful consequences; the third step evaluates the risk with tools from probabilistic risk assessment.The overall conclusion is that the proposed method brings the procedure and results of ship security analysis into the open and therefore allows for criticism, improvements and shared risk knowledge, not possible with less structured methods. The results also show that the calculated probabilities agree with available statistics, which indicates that the analysis succeeds in describing the central causal relationships of the scenarios modelled.
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| 5. |
- Liwång, Hans
(författare)
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Riskanalys inom fartygsskydd - en analysstrategi för bättre beslutsunderlag
- 2015
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Ingår i: Tidskrift i sjöväsendet. - Stockholm : Kungl. Örlogsmannasällskapet. - 0040-6945. ; :2, s. 151-168
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Sjöfartsskydd bedrivs idag både av militära styrkor och civila redare. Det är inte ofarligt, men nödvändigt och viktigt. Med fokus på säkerhetshot undersöker denna avhandling hur fartyg ska förbereda sig inför potentiellt farlig verksamhet, det vill säga hur man skapar ett lämpligt riskmedvetande i förhållande till fartygsskydd.Inom sjösäkerhet har regler, rekommendationer och metoder systematiskt utvecklats under många år. Inom sjöfartsskydd är däremot frågorna inte lika belysta och angreppssätten och erfarenheterna är ofta dolda bakom hemligstämplar. Det är rimligt att anta att riskanalysmetoder från andra områden kan användas även för sjöfartsskyddsanalyser, men inte utan att metoderna anpassas till områdets specifika behov. Därför leder den begränsade forskningen och dokumentationen inom området till ett kunskapsgap.För att reducera de identifierade utmaningarna inom sjöfartsskydd undersöks i avhandling hur en lämplig analysstrategi för fartygsskydd ser ut. För att öka den övergripande säkerheten för de analyserade verksamheterna ska metoden kunna stötta nödvändiga kompromisser mellan sjösäkerhet och fartygsskydd. Syftet är att utveckla en analysstrategi som är systematisk och som ger beslutsfattaren en lämplig bild av de aktuella riskerna. För att undersöka detta område behandlas i avhandlingen både hot mot militära fartyg och hotet mot civila fartyg från sjöröveri. Därför kan resultatet användas för att utveckla både militära doktriner och civila riktlinjer.Studien visar att hur fartygets verksamhet beskrivs i analysen är centralt för resultatet och därmed förståelsen av riskerna. Inte bara skyddslösningar i sig, utan även besättningens riskförståelse och hur det implementerade skyddet förstås måste inkluderas i analysen. Hur det implementerade skyddet förstås kommer också i stor utsträckning att påverka effektiviteten hos implementerade åtgärder. I avhandlingen konstateras också att om analysen görs utan att ta hänsyn till de osäkerheter som finns kan det innebära att resultatet är missvisande. Därför är den osäkerhetsanalys som är möjlig med ett kvantitativt angreppssätt nödvändig, speciellt om syftet är att identifiera robusta skyddsåtgärder.
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| 6. |
- Sturesson, Peter, 1981-, et al.
(författare)
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Pirani Microgauge Fabricated of High-Temperature Co-fired Ceramics with Integrated Platinum Wires
- 2019
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Ingår i: Sensors and Actuators A-Physical. - : Elsevier BV. - 0924-4247 .- 1873-3069. ; 285, s. 8-16
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents the integration and pressure sensor operation of platinum bond wires in High-Temperature Co-fired alumina (HTCC). Devices were fabricated with a 50 μm diameter wire suspended across a 500 μm wide cavity in green-body state HTCC, electrically connected to screen printed alumina conductors. The substrate shrinkage during sintering to a cavity width of 400 μm causes the wire element to elevate from the cavity´s bottom surface. Resulting devices were compared with reference devices, containing screen-printed sensor elements, as Pirani gauges operated at 100 °C in constant-resistance mode, and in dynamic mode with a feeding current of 1 A in a pressure range from 10−4 Torr to atmospheric pressure. Also, devices with wire lengths between 500 and 3500 μm were operated and studied in constant-resistance and dynamic mode. Lastly, a device is demonstrated in operation at a mean temperature of 830 °C. The results include wire elements with a consistent elevation from their substrate surfaces, with irregularities along the wires. The wire devices exhibit a faster pressure response in dynamic mode than the reference devices do but operate similarly in constant-resistance mode. Increasing the wire element length shows an increasing dynamic pressure range but a decreasing maximum sensitivity. The sensitivity is retained in high temperature mode, but the dynamic range is extended from about 10 Torr to about 700 Torr.
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| 7. |
- Amann, Daniel, 1967-, et al.
(författare)
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Affordability aspects in the concept generation of defence systems
- 2017
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Ingår i: Proceedings of 18th International CINet Conference. - Twente : Continuous Innovation Network. - 9789077360200 ; , s. 26-38
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Cost escalation for fighter aircraft is arguably not sustainable. Pushing frontiers oftechnology by incremental improvements of traditional platforms has led to anexponential increase in cost. This paper addresses the process of concept generationwith the purpose to explore how affordability is managed in that process, in order toidentify possible measures to improve the likelihood of generating affordableconcepts. This is done by studying two cases of concept generation of future combatair systems. The concepts generated in these two cases are however not curbing thecost escalation and are, with only one notable exception, based on incrementalinnovation. Nevertheless, the empirical observations offer leads to potentially fostera more innovative and cost conscious concept generation process, indicatingavenues for future research.
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| 8. |
- Amann, Daniel, et al.
(författare)
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Inducing Affordability?: Observations From An Experimental Study Of Concept Generation
- 2021
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Ingår i: Proceedings of the 22th CINet conference, September 12 – 14, Gothenburg, Sweden. - Enschede. - 9789077360248
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Konferensbidrag (refereegranskat)abstract
- Early preliminary concepts are claimed to have a profound impact on the final product. Since these concepts often are based on intuitive judgements, it is important that these judgements are appropriate for the desired outcome. Intuition is derived from what one brings to mind, and consequently, the access to information is important for making relevant judgements. Therefore, when a departure from a present path of development is sought for, access to new information is likely to be required. Results from an experimental study, addressing affordability and concept generation, indicated that individuals were influenced, by the provision of selective information, to make more cost considerations and even to change approach when generating new concepts. It was further recognized that weak abilities to estimate costs in a lifecycle and capability perspective likely hampered low-cost ambitions. The findings from this study are suggested to contribute to theory on product development, and to support affordability when new products are developed.
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| 9. |
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| 10. |
- Khaji, Zahra, et al.
(författare)
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Investigation of the storage and release of oxygen in a Cu-Pt element of a high-temperature microcombustor
- 2014
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Ingår i: The 14th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications(PowerMEMS 2014). - : Institute of Physics (IOP).
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Konferensbidrag (refereegranskat)abstract
- A miniature combustor for converting organic samples into CO2 with application in carbon isotopic measurements has been manufactured and evaluated. The combustor was made of High-Temperature Co-fired Ceramic (HTCC) alumina green tapes. The device has a built-in screen printed heater and a temperature sensor made of platinum, co-sintered with the ceramic. A copper oxide oxygen supply was added to the combustor after sintering by in-situ electroplating of copper on the heater pattern followed by thermal oxidation. Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and Thermal Gravimetric Analysis (TGA) were used to study electroplating, oxidation and the oxide reduction processes. The temperature sensor was calibrated by use of a thermocouple. It demonstrates a temperature coefficient resistance of 4.66×10−3/°C between 32 and 660 °C. The heat characterization was done up to 1000 °C by using IR thermography, and the results were compared with the data from the temperature sensor. Combustion of starch confirmed the feasibility of using copper oxide as the source of oxygen of combustion.
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