995 resultados para Rated voltages


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A series of solid electrolytes, (Ce(0.8)Ln(0.2))(1 - x)MxO2 - delta(Ln = La, Nd, Sm, Gd, M:Alkali-earth), were prepared by amorphous citrate gel method. XRD patterns indicate that a pure fluorite phase is formed at 800 degreesC. The electrical conductivity and the AC impedance spectra were measured. XPS spectra show that the oxygen vacancies increase owing to the MO doping, which results in the increase of the oxygen ionic transport number and conductivity. The performance of ceria-based solid electrolyte is improved. The effects of rare-earth and alkali-earth ions on the electricity were discussed. The open-circuit voltages and maximum power density of planar solid oxide fuel cell using (Ce0.8Sm0.2)(1 - 0.05)Ca0.05O2 - delta as electrolyte are 0.86 V and 33 mW . cm(-2), respectively.

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In this paper, we study the effects of electrical annealing at different voltages on the performance of organic light-emitting diodes. The light-emitting diodes studied here are single-layer devices based on a conjugated dendrimer doped with 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole as the emissive layer. We find that these devices can be annealed electrically by applying a voltage. This process reduces the turn-on voltage and enhances the brightness and efficiency. We obtained an external electroluminescence quantum efficiency of 0.07% photon/electron and a brightness of 2900 cd m(-2) after 12.4 V electrical annealing, which are about 6 times and 9 times higher than un-annealing devices, respectively. The improved luminance and efficiency are attributed to the presence of a space charge field near the electrodes caused by charging of traps.

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给出了一种基于分层式有限状态机的五自由度空间对接仿真平台控制系统设计方法,对状态机进行了扩展定义.增加了一个定义于状态上的变量属性集合,使其有利于系统的代码实现.结合控制系统采用的10 ms定时中断机制,将状态机层次划分到了可以分析每个10 ms硬件中断程序所需实现的控制功能状态及其转移、继承关系的程度,可以更清晰地设计出中断程序所需要的构成结构.系统的实际应用结果证明了上述方法的有效性.

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为中科院沈阳自动化研究所机器人中心研制了海洋救助机器人推进器用钕铁硼永磁直流电动机.针对该电动机设计的特殊性,重点论述电动机功率、电压、转速及主要尺寸的确定方法,主磁极、换向器和电刷装置的设计方法,对电动机的结构特点、电磁性能和实验结果也作了介绍.

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介绍了高精度微进给直线永磁同步电机伺服系统的 IP位置控制 ,提出了对该系统的最优预见前馈补偿 ,以提高系统的跟踪性能。为了能适应系统参数的变化 ,采用自适应神经元来实现预见前馈补偿。自适应神经元的输入向量为预见步数 ,权值为预见前馈系数 ,权值具有明确的物理意义 ,而且权的初始值不是随机数 ,而是系统在额定情况下算出的预见前馈系数 ,从而加快了神经元的调整速度 ,提高了系统的跟踪能力。仿真实验结果证明了所提出方案的有效性

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Accumulating studies have been conducted on job burnout in the fields of organizational psychology and health psychology, but there are few studies investigating job burnout for people in the Chinese Armed Police Force(CAPF). This thesis explored the antecedents (social comparison, perceived control and perceived organizational support) and outcomes (incumbents’ level of task performance and psychological health) of job burnout, using data collected from 458 teachers (study 1) and 792 officers (470 lower level army cadres,150 commandos and 172 teachers, study 2) in CAPF. Two studies were carried out. The results are as follows: 1. There were significant differences among the three dimensions of job burnout for teachers: reduced accomplishment was rated significantly higher than cynicism and emotional exhaustion. 2. For the emotional exhaustion dimension, special technical soldiers gave the highest ratings and cadres provided the lowest ratings. Besides, special technical soldiers and teachers rated higher on cynicism than cadres did. 3. Perceived control significantly influenced job burnout: the higher the perceived control, the lower the three dimension of job burnout (emotional exhaustion, cynicism and reduced accomplishment). 4. Perceived control exerted impacts on psychological health directly and indirectly: the higher the perceived control, the better psychological health. Moreover, perceived control had significant effects on psychological health through emotional exhaustion: the higher the perceived control, the lower emotional exhaustion and the better psychological health. 5. The higher perceived organizational support, the lower the three dimensions of job burnout; perceived organizational support impacted psychological health through emotional exhaustion: the higher perceived organizational support, the lower emotional exhaustion and the better psychological health. 6. Job burnout exerted significant influence on task performance: the higher reduced accomplishment, the lower task performance rated by participants themselves. Drawing on the above results, measures would be taken in CAPF to enhance perceived control and perceived organizational support, to alleviate burnout and improve task performance and psychological health.

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Mental dependence, characterized by craving and impulsive seeking behavior, is the matter of intensive study in the field of drug addiction. The mesolimbic dopamine system has been suggested to play an important role in rewarding of drugs and relapse. Although chronic drug use can induce neuroadaptations of the mesolimbic system and changes of drug reinforcement, these mechanisms cannot fully account for the craving and the compulsive drug-using behavior of addicts. Acknowledging the reinforcement effects of drugs, most previous studies have studied the impact of environmental cues and conditioned learning on addiction behavior, often using established classical or operant conditioning model. These studies, however, paid little attention to the role of cognitive control and emotion in addiction. These mental factors that are believed to have an important influence on conditioned learning. The medial prefrontal cortex (mPFC) has close anatomic and functional connections with the mesolimbic dopamine system. A number of the cognitive neurological studies demonstrate that mPFC is involved in motivation, emotional regulation, monitoring of responses and other executive functions. Thus we speculated that the function of abnormality in mPFC following chronic drug use would cause related to the abnormal behavior in addicts including impulse and emotional changes. In the present study of a series of experiments, we used functional magnetic resonance imaging to examine the hemodynamic response of the mPFC and related circuits to various cognitive and emotional stimuli in heroin addicts and to explore the underlying dopamine neuromechnism by microinjection of tool drugs into the mPFC in laboratory animals. In the first experiment, we found that heroin patients, relative to the normal controls, took a much shorter time and committed more errors in completing the more demanding of cognitive regulation in the reverse condition of the task, while the neural activity in anterior cingulate cortex (ACC) was attenuated. In the second experiment, the scores of the heroin patients in self-rating depression scale (SDS) and Self-rating anxiety scale (SAS) were significantly higher than the normal controls and they rated the negative pictures more aversive than the normal controls. Being congruent with the behavioral results, hemodynamic response to negative pictures showed significant difference between the two groups in bilateral ventral mPFC (VMPFC), amygdala, and right thalamus. The VMPFC of patients showed increased activation than normal controls, whereas activation in the amygdala of patients was weaker than that in normal subjects. Our third experiment showed that microinjection of D1 receptor agonist SKF38393 into the mPFC of rats decreased hyperactivity, which was induced by morphine injection, in contrast, D1 receptor antagonist SCH23390 increased the hyperactivity, These findings suggest: (1) The behavior and neural activity in ACC of addicts changed in chronic drug users. Their impulsive behavior might result from the abnormal neural activity in the mPFC especially the ACC. (2) Heroine patients were more depress and anxiety than normal controls. The dysfunction of the mPFC---amygdala circuit of heroine addicts might be related to the abnormal emotion response. (3) Dopamine in the mPFC has an inhibitory effect on morphine induced behavior. The hyperactivity induced by chronic morphine was reduced by dopamine increase with D1 receptor agonist, confirm the first experiment that the neuroadaption of mPFC system induced by chronic morphine administration appears to be the substrate the impulse behavior of drug users.

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As the foundation of other human resource practices, job analysis plays an essential role in HR management. Exploring sources of variance in job analysis ratings given by incumbents from the same job is of much significance to HRM practices. It can also shed lights on employee motivation in organizations. But previous studies in job analysis field have usually been conducted at individual level and take variance in job analysis ratings given by incumbents of the same job as error or bias. This dissertation takes the position that the variance may be meaningful based on role theory and other relevant theories. It first reviewed pervious studies on factors which may influence job analysis ratings provided by incumbents of the same job, and then investigated individual, interpersonal and organizational level variables which may exert impacts on these job analysis ratings, using multilevel data from 8 jobs of 1124 incumbents. The major findings are as follows: 1) Level of job performance and job attitudes affect incumbents’ job analysis ratings by incumbents of the same job at individual level. Specifically, incumbents with high level of job performance rated their job require higher levels of technical skills (power plant designers), and regarded information processing activities as more important to their job (book editors). Regarding the effects of job attitudes, incumbents of the four jobs with high level of job satisfaction gave higher importance and level ratings on organizational and cognitive skills, as well as higher level ratings on technical skills. Further, incumbents with higher affective commitment provided higher importance and level ratings of cognitive skills. Lastly, more involved job incumbents perceived organizational skills and cognitive skills as more important, and required at higher levels, for their job. 2) Leader-Member Exchange and goal structure also have effects on job analysis ratings by incumbents of the same job at interpersonal level. In good quality LMX relationship, news reporters rated decision-making activities and interpersonal activities as more important to their job. On the other side, when book editors structured their goals as cooperative with others’, they provided higher importance ratings on reasoning and interpersonal skills, and related personality requirements, as well as higher level ratings on reasoning abilities. 3) Worker requirements for the identical job are distinct from one organization to another. Specifically, there were between-organization differences in achievement orientation and conscientiousness related personality requirements. In addition, two dimensions of organizational culture, achievement-oriented culture and integrity-oriented culture in particular, were significantly associated with importance ratings of achievement orientation and conscientiousness related personality requirements respectively. Furthermore, achievement-oriented culture both directly and indirect (through job involvement) influenced achievement orientation related personality requirements. The results indicate that variation in job analysis ratings provided by incumbents of the same job may be meaningful. Future job analysis studies and practices should consider the impacts of these individual, interpersonal and organizational level factors on job analysis information. The results also have important implications for employee motivation concerning how organizational demands can be transformed into specific job and worker requirements.

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In current days, many companies have carried out their branding strategies, because strong brand usually provides confidence and reduce risks to its consumers. No matter what a brand is based on tangible products or services, it will possess the common attributes of this category, and it also has its unique attributes. Brand attribute is defined as descriptive features, which are intrinsic characteristics, values or benefits endowed by users of the product or service (Keller, 1993; Romaniuk, 2003). The researches on models of brand multi-attributes are one of the most studied areas of consumer psychology (Werbel, 1978), and attribute weight is one of its key pursuits. Marketing practitioners also paid much attention to evaluations of attributes. Because those evaluations are relevant to the competitiveness and the strategies of promotion and new product development of the company (Green & Krieger, 1995). Then, how brand attributes correlate with weight judgments? And what features the attribute judgment reaction? Especially, what will feature the attribute weight judgment process of consumer who is facing the homogeneity of brands? Enlightened by the lexical hypothesis of researches on personality traits of psychology, this study choose search engine brands as the subject and adopt reaction time, which has been introduced into multi-attributes decision making by many researchers. Researches on independence of affect and cognition and on primacy of affect have cued us that we can categorize brand attributes into informative and affective ones. Meanwhile, Park has gone further to differentiate representative and experiential with functional attributes. This classification reflects the trend of emotion-branding and brand-consumer relationship. Three parts compose the research: the survey to collect attribute words, experiment one on affective primacy and experiment two on correlation between weight judgment and reaction. The results are as follow: In experiment one, we found: (1) affect words are not rated significantly from cognitive attributes, but affect words are responded faster than cognitive ones; (2) subjects comprehend and respond in different ways to functional attribute words and to representative and experiential words. In experiment two, we fund: (1) a significant negative correlation between attributes weight judgment and reaction time; (2) affective attributes will cause faster reaction than cognitive ones; (3) the reaction time difference between functional and representative or experiential attribute is significant, but there is no different between representative and experiential. In sum, we conclude that: (1): In word comprehension and weight judgment, we observed the affective primacy, even when the affect stimulus is presented as meaningful words. (2): The negative correlation between weight judgment and reaction time suggest us that the more important of attribute, the quicker of the reaction. (3): The difference on reaction time of functional, representative and experiential reflects the trend of emotional branding.

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The nature of the distinction between conscious and unconscious knowledge is a core issue in the implicit learning field. Furthermore, the phenomenological experience associated with having knowledge is central to the conscious or unconscious status of that knowledge. Consistently, Dienes and Scott (2005) measured the conscious or unconscious status of structure knowledge using subjective measures. Believing that one is purely guessing when in fact one knows indicates unconscious knowledge. But unconscious structural knowledge can also be associated with feelings of intuition or familiarity. In this thesis, we explored whether phenomenological feelings, like familiarity, associated with unconscious structural knowledge could be used, paradoxically, to exert conscious control over the use of the knowledge, and whether people could obtain repetition structure knowledge. We also investigated the neural correlates of awareness of knowing, as measured phenomenologically. In study one, subjects were trained on two grammars and then asked to endorse strings from only one of the grammars. Subjects also rated how familiar each string they felt and reported whether or not they used familiarity to make their grammaticality judgment. We found subjects could endorse the strings of just one grammar and ignore the strings from the other. Importantly, when subjects said they were using familiarity, the rated familiarity for test strings consistent with their chosen grammar was greater than that for strings from the other grammar. Familiarity, subjectively defined, is sensitive to intentions and can play a key role in strategic control. In study two, we manipulated the structural characteristic of stings and explored whether participants could learn repetition structures in the grammatical strings. We measured phenomenology again and also ERPs. Deviant letters of ungrammatical strings violating the repetition structure elicited the N2 component; we took this to be an indication of knowledge, whether conscious or not. Strings which were attributed to conscious categories (rules and recollection) rather than phenomenology associated with unconscious structural knowledge (guessing, intuition and familiarity) elicited the P300 component. Different waveforms provided evidence for the neural correlates of different phenomenologies associated with knowledge of an artificial grammar.

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Two kinds of rating bias ——halo effect and ego-centric effect were analyzed in multitrait-multirater matrix by this research. To get the multitrait-multirater matrix, ten college students watched the video-tapes of football matches and rated the performance of the players on several traits. After the interviewing of 41 football fans, the performance traits of four different positions in a football team were obtained using critical incident technique. The results indicate: comparing the heterotrait-monorater triangless, some rater's rating showed halo effect obviously; comparing the monotrait-heterorater diagonals, ego-centric effect can be shown in some extent on different traits. There were less interrater reliability on the rating of some ambiguous traits. The conclusion can be used on rater training. We can give the raters feedback about their rating bias by analyzing the multitrait-multirater matrix. The results are also helpful for rater training.

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The MOS transistor physical model as described in [3] is presented here as a network model. The goal is to obtain an accurate model, suitable for simulation, free from certain problems reported in the literature [13], and conceptually as simple as possible. To achieve this goal the original model had to be extended and modified. The paper presents the derivation of the network model from physical equations, including the corrections which are required for simulation and which compensate for simplifications introduced in the original physical model. Our intrinsic MOS model consists of three nonlinear voltage-controlled capacitors and a dependent current source. The charges of the capacitors and the current of the current source are functions of the voltages $V_{gs}$, $V_{bs}$, and $V_{ds}$. The complete model consists of the intrinsic model plus the parasitics. The apparent simplicity of the model is a result of hiding information in the characteristics of the nonlinear components. The resulted network model has been checked by simulation and analysis. It is shown that the network model is suitable for simulation: It is defined for any value of the voltages; the functions involved are continuous and satisfy Lipschitz conditions with no jumps at region boundaries; Derivatives have been computed symbolically and are available for use by the Newton-Raphson method. The model"s functions can be measured from the terminals. It is also shown that small channel effects can be included in the model. Higher frequency effects can be modeled by using a network consisting of several sections of the basic lumped model. Future plans include a detailed comparison of the network model with models such as SPICE level 3 and a comparison of the multi- section higher frequency model with experiments.

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Lee, M. H., Lacey, N. J. (2003). The Influence of Epistemology on the Design of Artificial Agents. Minds and Machines, 13 (3), 367-395

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The main objective of this article is to present the results of a study aimed at determining, classifying and evaluating practices of interest for general competency development and assessment in undergraduate programmes. The study encompassed the following phases: (1) focus group in order to establish a starting point regarding competency development and assessment, counting on the opinion of some of the best-rated teachers belonging to the participating universities; (2) collection of best practices; (3) design and validation of a scale for the assessment of best practices; and (4) scale administration (evaluation of good practices) and data analysis.

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To Augustyn Surdyk numerous assumptions of constructivism and constructionism in the educational context seem to correspond with the idea of autonomisation in foreign language didactics. He presents a comparison of selected aspects of the three theories in question on the example of an innovative communicative technique of Role-Playing Games applied in the process of teaching foreign languages at an advanced level. The conventions of the technique with its simplified rules have been borrowed from popular parlour games and adapted by the author to the conditions of language didactics. The elements of play and simulation incorporated in the technique allow it to be rated among techniques of ludic strategy. (from Preface to the book)