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61.
A method for model order reduction is proposed using response-matching technique. The step and impulse inputs have been considered. All types of pole configurations in the original high-order and reduced low-order system are included in this paper like real, complex and repeated. The proposed method is comparable in quality with similar existing methods and is capable of generating a reduced-order model with a desired pole pattern. 相似文献
62.
中国气候对全球气温增暖的响应 总被引:4,自引:0,他引:4
近40年来,在全球气候变暖的背景下,中国气候也有明显的增暖趋势,北部增暖最明显,与全球平均温度变化相似,长江流域变暖不明显.冬季增暖最突出,夏季在部分地区有降温现象.近40年,全国平均降水量趋于减少,北部减少最明显,中心在华北及山东半岛;长江中上游降水偏丰.表明近期我国气候对全球气温变暖的响应特点,主要表现表式:北方为暖—干型;长江流域为冷—湿型;华南大部为弱暖—干型 相似文献
63.
《International Journal of Information Management》2016,36(5):735-747
Biometric technology is rapidly gaining popularity as an access control mechanism in the workplace. In some instances, systems relying on biometric technology for access control have not been well received by employees. One potential reason for resistance may be perceived privacy issues associated with organizational collection and use of biometric data. This research draws on previous organizational information handling and procedural fairness literature to frame and examine these underlying privacy issues. Perceived accountability, perceived vulnerability, and distrust were distilled from the previous literature as the primary dimensions of employee privacy concerns related to biometric technology. This study assesses the effects of these privacy concerns, how they vary based on the cultural influences of Anglos and Hispanics.Fire ground accountability is a critical management objective in the firefighting domain. In multi-unit or multi-agency crisis response scenarios, the on-scene incident commander tracks and accounts for each first responder. This research designed and deployed a new fire ground accountability system that tracked firefighters through finger pattern-based biometric logins to their assigned positions on the firefighting apparatus. An instrument measuring level of privacy concern on three underlying dimensions and demographic data was developed, validated and administered in a quasi-experimental field study. A pre-test–post-test survey methodology was employed to detect potential differences in privacy concerns as familiarity with the system increased. The study shows that Anglo and Hispanic subjects frame privacy issues differently associated with use of biometric technology in a fire ground accountability system. Finally, the study showed that some privacy concerns such as distrust and perceived vulnerability can be alleviated through system use with changes in post-use privacy concerns moderated by ethnic affiliation. 相似文献
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66.
根据第五方物流系统优化理论,对第五方物流系统进行优化,构建第五方物流模型,包括第五方物流体系功能结构模型和第五方物流信息系统结构模型,从而建立应急物流保障体系,并对应急响应时效优化项目进行实证分析,对创新协同服务应急物流组织模式、运营模式、保障模式、服务模式的可能性进行具体的研究。实证分析结果表明 ,可以实现应急物流保障体系系统优化的目标,为客户提供供应链系统集成、流程优化和资源协同服务。 相似文献
67.
The literature on teacher uncertainty suggests that it is a significant and perhaps inherent feature of teaching. Yet there is disagreement about the effects of these uncertainties on teachers as well as about the ways that teachers should regard them. Recognition of uncertainties can be viewed alternatively as a liability or an asset to effective teaching. Findings from the literature on uncertainties in teaching are summarized and analyzed, including explanations in the research about what accounts for and contributes to uncertainties. Recommendations for research and professional development are provided. 相似文献
68.
本文建立涡轮流量计动态数学模型 ,并对涡轮流量变送器的运动微分方程和传递函数进行了分析 ;从理论上计算得出 LW-1 5型涡轮流量计的单位阶跃速度响应 ;证明了限制涡轮流量计动态响应速度的瓶颈是流量积算仪的动态响应 ;最后提出了用软件代替流量积算仪的实验方案 相似文献
69.
Jia-ying Zhu Gong-yin Ye Qi Fang Cui Hu 《Journal of Zhejiang University. Science. B》2009,10(6):445-453
Although the biochemical dissection of parasitoid-host interactions is becoming well characterized, the molecular knowledge
concerning them is minimal. In order to understand the molecular bases of the host immune response to parasitoid attack, we
explored the response of Papilio xuthus parasitized by the endoparasitic wasp Pteromalus puparum using proteomic approach. By examining the differential expression of plasma proteins in the parasitized and unparasitized
host pupae by two-dimensional (2D) electrophoresis, 16 proteins were found to vary in relation to parasitization compared
with unparasitized control samples. All of them were submitted to identification by mass spectrometry coupled with a database
search. The modulated proteins were found to fall into the following functional groups: humoral or cellular immunity, detoxification,
energy metabolism, and others. This study contributes insights into the molecular mechanism of the relationships between parasitoids
and their host insects.
Project supported by the National Basic Research Program (973) of China (No. 2006CB102005), the National Natural Science Foundation
of China (Nos. 30571251 and 30170626), the Program for New Century Excellent Talents in University of the Ministry of Education
of China (No. NCET-05-0513), and the Innovation Research Team Program of the Ministry of Education of China (No. IRT0535) 相似文献
70.
Ya‐Chen Su 《Educational studies》2006,32(3):265-283
Due in large part to the trends towards economic globalization, English has become the most widely disseminated and ubiquitous international language. The purpose of the study was to investigate what Taiwan’s EFL teachers at the elementary level believe about the policy of English as a compulsory subject and how they perceive the benefits and obstacles of the policy’s implementation. Ten elementary English teachers in Tainan City and its suburban areas participated in this study. Data were collected through teachers’ interviews, classroom observation and document analysis. Results found that all ten teachers agreed with the policy for English as a compulsory subject at the elementary level. They observed both positive and negative sides of this top‐down policy. Classroom observation and interview data revealed that EFL teachers had to plan their English classes with the constraints on a large class of students with mixed levels of proficiency, limited teaching hours and resources. Parents’ expectations of and attitudes towards English learning also became an obstacle. 相似文献