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排序方式: 共有162条查询结果,搜索用时 31 毫秒
121.
Gaute Wangen Christoffer Hallstensen Einar Snekkenes 《International Journal of Information Security》2018,17(6):681-699
In general, an information security risk assessment (ISRA) method produces risk estimates, where risk is the product of the probability of occurrence of an event and the associated consequences for the given organization. ISRA practices vary among industries and disciplines, resulting in various approaches and methods for risk assessments. There exist several methods for comparing ISRA methods, but these are scoped to compare the content of the methods to a predefined set of criteria, rather than process tasks to be carried out and the issues the method is designed to address. It is the lack of an all-inclusive and comprehensive comparison that motivates this work. This paper proposes the Core Unified Risk Framework (CURF) as an all-inclusive approach to compare different methods, all-inclusive since we grew CURF organically by adding new issues and tasks from each reviewed method. If a task or issue was present in surveyed ISRA method, but not in CURF, it was appended to the model, thus obtaining a measure of completeness for the studied methods. The scope of this work is primarily functional approaches risk assessment procedures, which are the formal ISRA methods that focus on assessments of assets, threats, vulnerabilities, and protections, often with measures of probability and consequence. The proposed approach allowed for a detailed qualitative comparison of processes and activities in each method and provided a measure of completeness. This study does not address aspects beyond risk identification, estimation, and evaluation; considering the total of all three activities, we found the “ISO/IEC 27005 Information Security Risk Management” to be the most complete approach at present. For risk estimation only, we found the Factor Analysis of Information Risk and ISO/IEC 27005:2011 as the most complete frameworks. In addition, this study discovers and analyzes several gaps in the surveyed methods. 相似文献
122.
The tensile properties of polypropylene fibers, produced in a short-spin line, are correlated with the parameters of the three processing stages (spinning, drawing, and annealing), and with the molecular weight distribution. In general, tensile stiffness and strength increase with increasing molecular orientation, while the elongation at break decreases. The degree of orientation is determined by the deformation ratios and temperatures of the first two stages. Tensil modulus and strength also increase with increasing annealing stage shrinkage ratio. All the tensile properties, including the elongation at break, increase with increasing average molecular weight. The mechanisms of crystallization and deformation are related to the molecular weight distribution in different ways. Hence, the tensile modulus is highest for broad distributions when the draw ratio is low, and for narrow distributions when the draw ratio is high. The tensile strength increases and the elongation at break decreases as the width of the molecular weight distribution decreases, for all combinations of processing parameters. The distribution of tensile strength, for fibers with high draw ratios, broadens as the molecular weight distribution narrows. The total draw ratio of fibers, as experienced during processing and testing, and the true stress at break, are discussed in terms of deformation rates and relaxation times. © 1994 John Wiley & Sons, Inc. 相似文献
123.
This paper investigates the diesel engine performance and exhaust emissions with marine gas oil-alternative fuel additive. Marine gas oil (MGO) was selected as base fuel for the engine experiments. An oxygenate, diethylene glycol dimethyl ether (DGM), and a biodiesel (BD) jatropha oil methyl ester (JOME) with a volume of 10% were blended with the MGO fuel. JOME was derived from inedible jatropha oil. Lower emissions with diesel-BD blends (soybean methyl ester, rapeseed methyl ester etc.) have been established so far, but the effect of MGO-BD (JOME) blends on engine performance and emissions has been a growing interest as JOME (BD) is derived from inedible oil and MGO is frequently used in maritime transports. No phase separation between MGO-DGM and MGO-JOME blends was found. The neat MGO, MGO-DGM and MGO-JOME blends are termed as MGO, Ox10 and B10 respectively. The experiments were conducted with a six-cylinder, four-stroke, turbocharged, direct-injection Scania DC 1102 (DI) diesel engine. The experimental results showed significant reductions in fine particle number and mass emissions, PM and smoke emissions with Ox10 and B10 fuels compared to the MGO fuel. Other emissions including total unburned hydrocarbon (THC), carbon monoxide (CO) and engine noise were also reduced with the Ox10 and B10 fuels, while maintaining similar brake specific fuel consumption (BSFC) and thermal efficiency with MGO fuel. Oxides of nitrogen (NOx) emissions, on the other hand, were slightly higher with the Ox10 and B10 fuels at high engine load conditions. 相似文献
124.
Food allergy is an important issue in the field of food safety because of the hazards for affected persons and the hygiene requirements and legal regulations imposed on the food industry. Consumer protection and law enforcement require suitable analytical techniques for the detection of allergens in foods. Immunological methods are currently preferred; however, confirmatory alternatives are needed. The determination of allergenic proteins by liquid chromatography and mass spectrometry has greatly advanced in recent years, and gel-free allergenomics is becoming a routinely used approach for the identification and quantitation of food allergens. The present review provides a brief overview of the principles of proteomic procedures, various chromatographic set ups, and mass spectrometry instrumentation used in allergenomics. A compendium of published liquid chromatography methods, proteomic analyses, typical marker peptides, and quantitative assays for 14 main allergy-causing foods is also included. 相似文献
125.
PVC foils made from polymer grades having K-values of 58 and 68 have been milled at different temperatures and shear conditions on a two-roll mill. Compression molded foils were also made from the softest grade. The resulting samples have been studied using DSC and rotational dynamic rheometry at temperatures below and above the processing temperatures. DSC confirmed the correlation between the processing temperature and the temperature Tb separating endotherm A and B. However, this correlation is only valid for high processing temperatures (≥150°C). Also, if the processing temperature is lowered at the end of the processing, Tb will be lower than the maximum processing temperature. In most cases the area of endotherm A increased with increasing processing temperature and shear. From measurements of tan(δ) we find that when measuring at a temperature below the lowest processing temperature, the higher the degree of fusion, the larger is the relative amount of the elastic energy stored. Measuring at a temperature above the highest processing temperatures yields the opposite result. In between there is a transition zone where polymer grades having different M?w respond differently to changes in thermomechanical processing history. These and other observations are discussed in terms of the gel-destruction temperature introduced by Lyngaae-Jørgensen, the breakdown of the particulate structure, and the creation of a three-dimensional fusion network held together by ordered and crystalline regions. 相似文献
126.
Anna-Maria M. R. Persson Einar L. Hinrichsen Erik Andreassen 《Polymer Engineering and Science》2020,60(7):1642-1661
The usage of thermoplastic elastomers (TPEs) is increasing, and integrated hard-soft parts can be mass produced by two-component injection molding (or sequential molding). A key property of such parts, the adhesion between the two materials, is the topic of this study. The hard part (the first molded component) in this study was polyamide-12 with 0 to 50 wt% glass fibers (PA12-GF). As the second component, two TPEs were used: a vulcanized TPE and a styrenic TPE, both modified for adhesion to polyamides. The adhesion, assessed by 90° peel tests, increased with increasing melt temperatures and TPE injection rate, while it decreased with increasing glass fiber fraction in the PA12-GF. Based on characterization of cross-sections and fiber distributions near the interface, we propose some hypotheses for the effect of fiber fraction on the fusion between PA12-GF and TPE. These hypotheses involve the near-surface properties of the PA12-GF materials, microstructure, thermo-mechanical properties, and thermal properties. A direct effect of increasing the glass fiber fraction, that is, a reduction in adhesion as more fibers are present at the interface, does not seem to be a major effect, since few fibers are in direct contact with the TPE for any fiber fraction. 相似文献
127.
In wireless sensor networks there is a need to securely store monitored data in a distributed way whenever it is either not desired or simply not possible to transmit regional volatile information to an authorised recipient in real-time. In particular, for wireless sensor network applications with an asynchronous character, the wireless sensor network itself needs to store the monitored data. Since nodes may disappear over time, a replicated and read-protected, but yet space- and energy-efficient, data storage is mandatory. In this work we provide and analyse an approach for a tiny Persistent Encrypted Data Storage (tinyPEDS) of the environmental fingerprint for asynchronous wireless sensor networks. Even if parts of the network are exhausted, restoring rules ensure that, with a high probability, environmental information from past is still available. 相似文献
128.
Java technology has seen an impressive growth in popularity since its introduction in 1995. Although ithas foremost proved its usefulness in the Internet domain, powerful marketactors are currently moving Java into the embedded systems domain. In thisarticle we identify major design issues in embedded systems, and analyze thesuitability of Java technology in such systems. We find that Java technologycan contribute to the embedded system design process on a system level byfacilitating higher run-time reliability and the technology can simplify maintenanceof the product throughout its life cycle. In addition, programmer efficiencyand productivity may be improved, especially for web based applications anddistributed embedded systems. 相似文献
129.
130.
Idiosyncratic drug-induced liver injury (DILI) is an underreported and underestimated adverse drug reaction. Information on the documented hepatotoxicity of drugs has recently been made available by a website that can be accessed in the public domain: LiverTox (http://livertox.nlm.nih.gov). According to critical analysis of the hepatotoxicity of drugs in LiverTox, 53% of drugs had at least one case report of convincing reports of liver injury. Only 48 drugs had more than 50 case reports of DILI. Amoxicillin-clavulanate is the most commonly implicated agent leading to DILI in the prospective series. In a recent prospective study, liver injury due to amoxicillin-clavulanate was found to occur in approximately one out of 2300 users. Drugs with the highest risk of DILI in this study were azathioprine and infliximab. 相似文献