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111.
This obituary describes the professional career of Robert J. Wherry, which spanned 48 years, from 1927 to 1975. Wherry was an exceptional example of a quantitative-industrial psychologist who was able to make independent, original academic contributions, and yet have an exceptional understanding of problems of application. Throughout his career, two of Wherry's overriding interests were in the development and application of statistical models for prediction and factor analysis. In addition to his contributions to the quantitative literature, Wherry made substantial contributions to industrial psychology, publishing extensively in the industrial literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In a cascaded plant with n sensing points, n independent feedback loops are available to achieve quantitative sensitivity specifications. The optimum design is defined as that which achieves this with minimum net effect, of the n sensor noise sources, at the plant input. A design procedure is presented wherein one works backwards step by step from the system output, designing each loop function Li almost as if the remaining loops (Li+j, j>0) are perfect. Even in large plant ignorance problems, only the outer loop Li may be large over some frequency range. In general |Li|max < 1, i ≠ 1 and |Li+1|max < |Li|max. Each Li has only one distinct frequency range say at ωc, i requiring trade-off between Li and Li+1. Only in this range is significant design effort required. However, ωc, i+1 >ωc, i so the primary price paid is in the steadily increasing “bandwidth” of each loop. The design procedure is highly transparent with strong universalistic features, permitting the use of universal design curves. 相似文献
114.
Compared the rate of learning-set formation by 4 rhesus monkeys that had previously been pretrained on the win-stay component of the learning-set strategy (Group WS) to the rate evidenced by 4 others that had pretraining on the lose-shift component (Group LS). Differences between groups were small, and asymptotic levels were below those previously obtained by monkeys without pretraining. The negative transfer resulted from generalized tendencies to perseverate or shift (Groups WS and LS, respectively), regardless of response outcome. The former tendency dissipated relatively rapidly, while the latter persisted very markedly throughout the 400-problem learning-set series. It is noted that learning-set formation requires a balance between the win-stay and lose-shift components; however, the optimal ratio is unknown. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
115.
Isaac Wang 《电子元器件资讯》2009,(12)
据iSuppli公司,由于中国政府投资于安防领域以及消费者青睐住宅安全系统,中国安防和监视设备市场有望经受住经济衰退的冲击,并在2009年及以后不断扩张.
iSuppli公司预测,中国的安防产业将在2009年达到189亿美元,比2008年时的175亿美元增长7.5%.到2013年,该市场将扩大到265亿美元,2008-2013年的年复合增长率可达8.6%.相比之下,2008年全球安防市场的营业收入预计萎缩2%. 相似文献
116.
Isaac Pilatowski Sabah Mounir Joseph Haddad Duong Thai Cong Karim Allaf 《Food and Bioprocess Technology》2010,3(6):901-907
The instant controlled pressure drop (DIC) process was used as a post-harvesting treatment, followed by hot air drying and
shade polishing. DIC treatment, which is carried out at P = 0.4–0.6 MPa, has many advantages in terms of processing time (not exceeding 30 s) and drying kinetics (about 3 h instead
of 1 day under standard 50 °C hot air flow conditions). Shade polishing gives high quality rice with a whole-grain yield of
68-70% rather than the usual 52-60%. A tasting evaluation was carried out by an international panel and the rice was found
to be perfect after a cooking time of 6 min, with an overcooked time of 18 min as against 17 min and 20 min, respectively,
for conventional products. The shaded shelf life of the final product is much longer than 18–24 months. 相似文献
117.
Electrospun nanofibers are most often produced by needle electrospinning process, which has inherent disadvantages like clogging and low efficiency. In this study, an alternative needleless electrospinning process is reported for the fabrication of nanofibers based on a novel spinneret. Firstly, a spinneret with a 0.5‐mm diameter hole in the middle of a flat plastic cap was custom‐made that may be readily scaled up for mass production. Then, polyethylene oxide (PEO) aqueous solution with 6.0 wt% concentration was used to demonstrate the needleless electrospinning process. The processing window for the jet formation in the flat spinneret electrospinning process was determined. The relationships between various processing parameters (applied voltage, working distance, and flow rate) and the resultant PEO nanofibers were also investigated. It was found that stable fluid jet launched from the tip of the coned droplet anchored at the rim of the hole and formed fibers. The morphology and diameter of electrospun fibers were examined using scanning electron microscopy. The results show that PEO nanofibers produced by this needleless electrospinning have similar structure and morphology to those from the single needle source. Finally, the hole number of spinneret was increased to four holes, which was still able to produce smooth nanofibers with a higher production rate. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers 相似文献
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119.
Isaac Deng Frances Corrigan Sanjay Garg Xin-Fu Zhou Larisa Bobrovskaya 《International journal of molecular sciences》2021,22(14)
Parkinson’s disease (PD) is the most common movement disorder, characterized by progressive degeneration of the nigrostriatal pathway, which consists of dopaminergic cell bodies in substantia nigra and their neuronal projections to the striatum. Moreover, PD is associated with an array of non-motor symptoms such as olfactory dysfunction, gastrointestinal dysfunction, impaired regulation of the sleep-wake cycle, anxiety, depression, and cognitive impairment. Inflammation and concomitant oxidative stress are crucial in the pathogenesis of PD. Thus, this study aimed to model PD via intrastriatal injection of the inflammagen lipopolysaccharide (LPS)to investigate if the lesion causes olfactory and motor impairments, inflammation, oxidative stress, and alteration in synaptic proteins in the olfactory bulb, striatum, and colon. Ten µg of LPS was injected unilaterally into the striatum of 27 male C57BL/6 mice, and behavioural assessment was conducted at 4 and 8 weeks post-treatment, followed by tissue collection. Intrastriatal LPS induced motor impairment in C57BL/6 mice at 8 weeks post-treatment evidenced by reduced latency time in the rotarod test. LPS also induced inflammation in the striatum characterized by increased expression of microglial marker Iba-1 and astrocytic marker GFAP, with degeneration of dopaminergic neuronal fibres (reduced tyrosine hydroxylase immunoreactivity), and reduction of synaptic proteins and DJ-1 protein. Additionally, intrastriatal LPS induced inflammation, oxidative stress and alterations in synaptic proteins within the olfactory bulb, although this did not induce a significant impairment in olfactory function. Intrastriatal LPS induced mild inflammatory changes in the distal colon, accompanied by increased protein expression of 3-nitrotyrosine-modified proteins. This model recapitulated the major features of PD such as motor impairment and degeneration of dopaminergic neuronal fibres in the striatum, as well as some pathological changes in the olfactory bulb and colon; thus, this model could be suitable for understanding clinical PD and testing neuroprotective strategies. 相似文献
120.