To meet the demand of improved comfort for passengers, drive ability and standard in fuel economy; external variable displacement swash (wobble) plate type compressors are used in automobile air conditioning control system because of their low energy consumption and highly efficient characteristics. It controls the compressor displacement by increasing or reducing the swash plate angle. Solenoid operated electromagnetic control valve (ECV) in the compressor controls the air conditioning system by means of a pulse width modulation (PWM) input signal supplied from an external source (controller). The mechanism changes the swash plate angle by increasing or reducing the pressure of swash plate chamber using the ECV functions. The force (solenoid) for ECV operation is important as the force directly related to the movement of the internal feature i.e. mainly plunger of the ECV which is responsible for the amount of air/refrigerant flow that results the air conditioning control procedures with various pressure ports. The research paper highlights the improved theory and equation for calculating the working force (solenoid force) in ECV and experimental analysis of 3 (three) ECV samples followed by the comparison of theoretical and experimental force results. 相似文献
To understand effects of milling, scented rice ‘Cheonjihyang-1-se’ was milled from 10 to 140 s and changes in volatiles, phytonutrients, and fatty acids were evaluated. Among 43 identified odor-active compounds, four volatiles, including hexan-3-one, exhibited decreases of up to 78%, while four others including (E)-non-2-enal, increased following milling. Levels of 2-acetyl-1-pyrroline, the most distinctive popcorn-flavoring compound in scented rice, were not affected by the degree of milling (DM). Partial least squares discriminant analyses of volatiles were able to differentiate white rice according to the DM. Benzene and 2-pentylfuran showed the highest variable importance in projection scores, which could be applied in estimating the DM of rice. Milling significantly decreased tocopherols, tocotrienols, squalene, phytosterols contents and oleic acid composition, while palmitic acid composition was increased. These results suggest milling-dependent variations in phytonutrient levels and lipid composition, as well as changes in aroma and subsequent market quality, in ‘Cheonjihyang-1-se’ rice. 相似文献
Utilizing the extra-ordinary properties of carbon nanotube (CNT) in metal matrix composite (MMC) for macroscopic applications is still a big challenge for science and technology. Very few successful attempts have been made for commercial applications due to the difficulties incorporating CNTs in metals with up-scalable processes. CNT reinforced copper and copper alloy (bronze) composites have been fabricated by well-established hot-press sintering method of powder metallurgy. The parameters of CNT–metal powder mixing and hot-press sintering have been optimized and the matrix materials of the mixed powders and composites have been evaluated. However, the effect of shape and size of metal particles as well as selection of carbon nanotubes has significant influence on the mechanical and electrical properties of the composites. The hardness of copper matrix composite has improved up to 47% compared to that of pure copper, while the electrical conductivity of bronze composite has improved up to 20% compared to that of the pure alloy. Thus carbon nanotube can improve the mechanical properties of highly-conductive low-strength copper metals, whereas in low-conductivity high-strength copper alloys the electrical conductivity can be improved. 相似文献
Greenhouse gases emitted from the excessive use of fossil fuels are threatening the environment, and thus alternative resources like biomass are being considered as a replacement. Biomass with high moisture content is better treated by hydrothermal carbonization method than any other process to generate biofuel. Research on this method on a lab scale has progressed recently. However, due to the complex reaction mechanisms and operational barriers, more improvements are required to make it a commercial technology. This paper aims to review the development of hydrothermal carbonization with a focus on the practical aspects of the process. Many references have been reviewed critically to provide a well-structured source for improving this process. After providing information about the biomass structure and general knowledge of hydrothermal carbonization, the challenges faced in attempts to improve the process have been identified as lack of valid kinetic and heat transfer models and insufficient data on continuous and large-scale reactors. Useful and practical suggestions have been presented to tackle all these challenges. 相似文献
OBJECTIVE: To examine the differences between independent and behavior-dependent stressful life events and chronic adversities in child psychiatric patients, community controls, and children with asthma. METHOD: The Psychosocial Assessment of Childhood Experiences was used to assess recent severe events (life events with high long-term threat) and major adversities (long-term experiences with high negative impact on child) in children attending a psychiatric clinic (n = 99), community controls (n = 26), and children with chronic asthma (n = 94). RESULTS: In the previous year, the psychiatric patients had, on average, experienced significantly more independent and behavior-dependent severe events and major adversities than either the controls or the asthmatic patients. The differences were most pronounced in relation to behavior-dependent high-threat life events and long-term-experiences. Among the psychiatric patients, one third of all severe events and one quarter of all major adversities were dependent on the child's behavior. The corresponding proportions in the controls and children with asthma were between one fifth and one twelfth. CONCLUSIONS: Psychiatrically disturbed children have an increased risk of experiencing behavior-dependent life events and long-term adversities compared with their peers in the community at large and compared with children suffering from a chronic physical illness such as asthma. Future studies need to examine the possible contributions of such experiences to the development and maintenance of psychiatric and physical illness in children. 相似文献
Mobile Networks and Applications - In mobile crowd-sensing, smartphone users take part in sensing and then share the data to the server (cloud) and get an incentive. These data can be utilized for... 相似文献
Fault tree analysis is still widely practiced in high-hazard industries. We propose in this article an algorithm for the reduction of fault tree expressions that are generated from automata representations of failure behaviors. Automata formalisms are increasingly being used to describe systems exhibiting sequence-dependent failures—i.e., the overall outcome like a total failure of the system can depend on the order in which events occur. A set of paths leading to a safety-relevant state is encoded as a standard sum of product canonical form, and without any loss of the significance of the sequencing of events. That is, the corresponding fault tree expression is basically a Boolean formula which is extended with the necessary temporal features (event occurrence priority). Such expressions can then be reduced into minimal canonical forms by using the Boolean methods together with the required temporal logic calculus. Since minimal failure sequences can be determined from the obtained reduced models, the proposed approach can improve the analysis of the dynamic effects of the sequencing of faults and propagated errors in such models. As a consequence, it can have a positive impact on the design of failure prevention measures. A fault tolerant example system exhibiting dynamic behavior is used to highlight the benefits of the approach.