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31.
以连接端子、印刷电路板和电镀通孔3种不同材料构成的一种可拔插截面针型汽车电子连接器为研究对象,为满足其在非塑性状态下相互接触实现可反复拔插、稳定低电阻的连接要求。针对连接可靠性设计问题,利用接触动力学理论,对基于设计参数变化的连接器米赛斯应力和接触应力分布进行了解析和灵敏度分析,得到了影响其连接性能的关键设计参数。文中为减少高精度设计参数灵敏度解析的计算时间,提出了将连接端子前、后段形态设计参数分离的解析法,即在接触力学解析过程中,首先以准静态接触方法对连接端子后段(连接形态)设计参数进行接触力学解析,再以动态接触方法对连接端子前段(插拔形态)设计参数进行接触力学解析的方法。其结果对同类微小型可拔插截面针型汽车电子连接器设计参数的确定具有参考价值。 相似文献
32.
The n-6/n-3 fatty acid (FA) ratio has increased in the Western-style diet to ~10–15:1 during the last century, which may have
contributed to the rise in cardiovascular disease (CVD). Prior studies have evaluated the effects on CVD risk factors of manipulating
the levels of n-6 and n-3 FA using food and supplements or investigated the metabolic fate of linoleic acid (LNA) and α-linolenic
acid (ALA) by varying the n-6/n-3 ratios. However, no previous studies have investigated the potential interaction between
diet ratios and supplementation with eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). We used
a factorial design approach with adults (n = 24) in a controlled feeding trial to compare the accretion of EPA and DHA into red blood cell membranes (RBC) by adding
a direct source (algal oil supplement) of EPA and DHA in a diet with a 10:1 versus 2:1 ratio of n-6/n-3 FA. Subjects were
randomized into 8-week crossover diet sequences and each subject consumed three of four diets [10:1, 10:1 plus supplement
(10:1 + S), 2:1 and 2:1 + S]. LNA and ALA intakes were 9.4 and 7.7%, and 1.0 and 3.0% during the low and high ALA diets, respectively.
Compared to the Western-style 10:1 diet, the 2:1 diet increased EPA by 60% (P < 0.0001) in RBC membranes without the direct EPA source and a 34% increase (P = 0.027) was observed with the 10:1 + S diet; however, DHA levels increased in both diet ratios only with a direct DHA source.
Shifting towards a 2:1 diet is a valid alternative to taking EPA-containing supplements. 相似文献
33.
Bin He Yi Wang Keiji Takase Goro Mouri Bam H. N. Razafindrabe 《Water Resources Management》2009,23(9):1863-1873
Anthropogenic activities have exerted increasingly large-scale influences on terrestrial ecological systems from the past
century, primarily through agriculture; however, the impact of such changes on the hydrologic cycle is poorly understood.
As one of the important land use (LU) in the coastal Dogo Plain of the Seto Inland Sea, Japan, paddy fields have been decreasing
with the increase in urbanization in recent decades. As the main source of water in the Dogo Plain, groundwater plays an important
role in providing people with fresh water and contributing to stream base flow. The purpose of this study is to analyze the
water resource and evaluate the effect of LU change on groundwater table fluctuation in this coastal plain. Firstly, the observations
of groundwater table and the investigation of water balance were carried out in this alluvial plain. Then, a distributed four-block
three-layer water balance model was employed to analyze the groundwater table fluctuation with response to the change of paddy
field area. Moreover, the role of paddy field in recharging groundwater in the basin has been clarified. Results show that
groundwater table depends not only on rainfall and discharge from rivers, but also on irrigation water and topology of the
study area. The net groundwater recharge was positive in irrigation periods whereas that in non-irrigation periods was nearly
equal to zero or negative. The results of this study would be helpful to the urban development policy and land use planning
decision. 相似文献
34.
Yui Tanaka Tadao Nakagomi Itaru Suzuki Kou Matoba Keiji Murayama 《Welding International》2013,27(6):422-430
We conducted the welding experiment using three kinds of test piece, actual size, diaphragm and butt joint. Then, we examined the influence on strength, cooling time and carbon equivalent of weld metal by welding conditions on the different test pieces. We calculated an estimate of cooling time and chemical components. Consequently, we concluded that the strength of weld metal can be estimated by heat input, interpass temperature, carbon equivarent of welding wire and shape of test piece. 相似文献
35.
Ill Yong Kim Ryota Iwatsuki Koichi Kikuta Yumi Morita Toshiki Miyazaki Chikara Ohtsuki 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1472-1476
Osteoconductive materials with self-setting ability have received much attention because their properties allow developing injectable materials for bone defects. Thermosensitive hydrogel with ability of bone-like apatite formation in a body environment is a candidate of injectable bone fillers with osteoconductivity because the apatite formation on materials is an essential to show osteoconduction. The present study focused on the development of a thermosensitive hydrogel through modifications of the sulphonic groups of the polysaccharide, κ-carrageenan, with potassium chloride (KCl) and calcium chloride (CaCl2). We found that the gelation temperature of κ-carrageenan solutions increased with increasing amounts of K+ ions. Apatite formation was observed on the gel after exposure to simulated body fluid for 0.5 day when the gel was prepared with a molar ratio of Ca2+/sulfonic groups = 1.5. These results indicate that a thermosensitive κ-carrageenan hydrogel with apatite-forming ability was obtained through the incorporation of K+ and Ca2+ ions into the solution. 相似文献
36.
Er-doped fibre ring resonator applied to optical spectrum analyser with less than 100 kHz resolution
A fibre optic ring resonator is proposed which uses an Er-doped fibre amplifier to compensate for round-trip optical loss thereby enhancing resonator finesse. It is operated as a scanning-ring spectrum analyser and attains a resolution better than 100 kHz.<> 相似文献
37.
Hideki Kokame Kentaro Hirata Keiji Konishi Takehiro Mori 《International journal of control》2013,86(6):537-546
Supposing a non-linear system is subjected to parametric uncertainties, the present paper aims at stabilizing its unstable steady states. A distinctive feature of the problem is that exact information about the steady state is unavailable. To cope with the difficulty, we have examined the applicability of the state difference feedback which uses the difference between the present state x(t) and the past state x(t-T). A rigorous stability analysis has been executed for the case where state deviations are controllable by a single input variable. The stability analysis has led to a favourable conclusion that if the number of unstable modes is just two, and if they are not associated with the origin in the complex plane, we are always able to find a controller which stabilizes the deviations from the unknown steady state. Design process is illustrated by using two kinds of pendulum systems. 相似文献
38.
Keiji Tsukada Mitsuteru Yoshioka Yoshihiko Kawasaki Toshihiko Kiwa 《NDT & E International》2010,43(4):323-328
We have developed a magnetic flux leakage (MFL) system using magnetic resistive (MR) sensors for detecting two dimensional magnetic field components, and an induction coil that generates low magnetic field strengths and extremely low frequencies. The signal at each scanned measurement point (i) was divided by the signal strength Mmes,i and phase αi by a lock-in amplifier. Using the strength Mmes,i and phase αi, we calculated the imaginary part of the signal using the common phase β. By optimization of the common phase β to the imaginary part, the analyzed scanning data curve was shown to be effective in estimating the size (depth and diameter) of back-side pits on a ferrous plate. Comparing the two dimensional magnetic field components of leakage, the imaginary part of the y-component parallel to the induced magnetic field was found to be suitable for detecting the back-side pits. 相似文献
39.
Toru Ikegami Tomotake Morita Shunichi Nakayama Hideyuki Negishi Dai Kitamoto Keiji Sakaki Yasunori Oumi Tsuneji Sano Kenji Haraya Hiroshi Yanagishita 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(8):1172-1177
BACKGROUND: Pervaporation employing ethanol‐permselective silicalite membranes as an alternative to distillation is a promising approach for refining low‐concentration bioethanol solutions. However, to make the separation process practicable, it is extremely important to avoid the problems caused by the adsorption of succinate on the membrane during the separation process. In this work, the pervaporation of an ethanol fermentation broth without succinate was investigated, as well as the influence of several fermentation broth nutrient components. RESULTS: Candida krusei IA‐1 produces an extremely low level of succinate. The decrease in permeate ethanol concentration through a silicone rubber‐coated silicalite membrane during the separation of low‐succinate C. krusei IA‐1 fermentation broth was significantly improved when compared with that obtained using Saccharomyces cerevisiae broth. By treating the fermentation broth with activated carbon, bioethanol was concentrated as efficiently as with binary mixtures of ethanol/water. The total flux was improved upto 56% of that obtained from the separation of binary mixtures, compared with 43% before the addition of activated carbon. Nutrients such as peptone, yeast extract and corn steep liquor had a negative effect on pervaporation, but this response was distinct from that caused by succinate. CONCLUSION: For consistent separation of bioethanol from C. krusei IA‐1 fermentation broth by pervaporation, it is useful to treat the low nutrient broth with activated carbon. To further improve pervaporation performance, it will be necessary to suppress the accumulation of glycerol. Copyright © 2009 Society of Chemical Industry 相似文献
40.
Izumi Kita Tomohiro Shibata Yuki Kamiya Daishi Kato Kazuo Kunieda Keiji Yamada Kazushi Ikeda 《Artificial Life and Robotics》2009,14(3):375-378
To increase the productivity of knowledge workers, it is necessary to manage their organization so that they are motivated
to collaborate with each other for their synergy. However, it is difficult for managers to grasp the explicit interactions
of workers in the organization all the time. Owing to advanced communications technology, and the reduced size and improved
capabilities of computers, we are able to record group behaviors as logging data in the office. The aim of this study is to
extract features of group behavior from long-range office-logging data. We apply principal component analysis to the data
matrix whose element is the mean travel velocity calculated from an individual’s trajectory per day. The results demonstrate
the feasibility of our approach, since nontrivial informative group features can be extracted. 相似文献