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排序方式: 共有480条查询结果,搜索用时 734 毫秒
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A model warehouse with carefully regulated environmental conditions was used to study the behavior of adult Indian meal moths during commodity infestation. Sequences of moth distributions in the warehouse, calculated by spatial analysis, clearly showed the coordinated movements of moth populations from eclosion to death. Many facets of adult behavior in a warehouse were coordinated with the photoperiod. Adult moths emerged at the end of a photophase and fairly rapidly moved to the walls and, to a lesser extent, to the undersides of the commodity pallets. Most females are mated in the first 24 h after emergence, largely during the scotophase. Air circulation within the warehouse probably compromised pheromone-directed guidance of males to females, although pheromones may still have a major role in regulating other aspects of male mating behavior. When mating subsided, many of the males flew upwind to the air circulating unit, but only during the photophases. The females moved to the return air side of the warehouse and then migrated towards the same end as the males, but only during the scotophases. They moved from pallet to pallet largely by walking on the warehouse floor and laid eggs in or on the cups of commodity. Direct oviposition on the commodity during the infestation period was lower than expected, probably because commodity odors were dissipated by air circulation and did not provide appropriate orientation. At 144 h after emergence, 90% of the moth population had died. 相似文献
3.
Studies were undertaken on the isolation and identification of reaction products of ammonium nitrate phosphate (ANP) fertilizers containing 30, 50 and 70 per cent water-soluble phosphorus (WSP) of total phosphorus in representative soils of the vertisol, oxisol, alfisol, entisol, mollisol and aridisol groups of India. ANP fertilizers were applied in solid form to soil, and reaction products formed at and around the site of ANP fertilizer placement were identified after six weeks incubation in moist soils by X-ray diffraction technique. DCPD (dicalcium phosphate dihydrate- CaHPO4 · 2H2O) was the major reaction product of ANP fertilizers containing 30 and 50 per cent WSP in vertisol, entisol, aridisol, mollisol, oxisol and alfisol, and of ANP containing 70 per cent WSP in vertisol, entisol, alfisol, aridisol and mollisol. DCP (dicalcium phosphate-CaHPO4) was detected with ANP of 30 and 50 per cent WSP in the vertisol, alfisol, entisol, mollisol and aridisol groups of soils. In addition to DCPD, FePO4 · 2H2O (metastrengite) and AlPO4 · 2H2 O-monoclinic (metavariscite) were formed in alfisol and oxisol soils with ANP of 30 and 50 per cent WSP. FePO4 · 2H2O and AlPO4 · 2H2O (metavariscite) were identified in alfisol and oxisol soils while AlPO4 · 2H2O-orthorhombic (variscite) was formed in alfisol soils with ANP of 70 per cent WSP. 相似文献
4.
Need and importance of modelling in human body vibration research studies are well established. The study of biodynamic responses of human beings can be classified into experimental and analytical methods. In the past few decades, plenty of mathematical models have been developed based on the diverse field measurements to describe the biodynamic responses of human beings. In this paper, a complete study on lumped parameter model derived from 50th percentile anthropometric data for a seated 54- kg Indian male subject without backrest support under free un-damped conditions has been carried out considering human body segments to be of ellipsoidal shape. Conventional lumped parameter modelling considers the human body as several rigid masses interconnected by springs and dampers. In this study, concept of mass of interconnecting springs has been incorporated and eigenvalues thus obtained are found to be closer to the values reported in the literature. Results obtained clearly establish decoupling of vertical and fore-and-aft oscillations. 相似文献
5.
Sherif Abdleazeem Ezzat El-Sherif 《International Journal on Document Analysis and Recognition》2008,11(3):127-141
In this paper, we fill a gap in the literature by studying the problem of Arabic handwritten digit recognition. The performances
of different classification and feature extraction techniques on recognizing Arabic digits are going to be reported to serve
as a benchmark for future work on the problem. The performance of well known classifiers and feature extraction techniques
will be reported in addition to a novel feature extraction technique we present in this paper that gives a high accuracy and
competes with the state-of-the-art techniques. A total of 54 different classifier/features combinations will be evaluated
on Arabic digits in terms of accuracy and classification time. The results are analyzed and the problem of the digit ‘0’ is
identified with a proposed method to solve it. Moreover, we propose a strategy to select and design an optimal two-stage system
out of our study and, hence, we suggest a fast two-stage classification system for Arabic digits which achieves as high accuracy
as the highest classifier/features combination but with much less recognition time. 相似文献
6.
汤鸣红 《常州信息职业技术学院学报》2006,5(2):77-79
印度NIIT教学方法确保学员不仅全面掌握业界的主流软件开发技术,而且获得自我学习、自我提高的能力,从而在技术飞速更新的IT行业胜任挑战性职务。对NIIT的教学特色做了较详细的分析,并在如何将其精华引入我院教学体系上进行了实践和探讨。 相似文献
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As the population of American Indians and Alaska Natives continues to expand in the 21st century United States, an increasing number of professional psychologists will be called upon to provide culturally appropriate mental health services for Native American people and their communities. This article provides a general overview of contemporary tribal America before describing the legal, political, and institutional contexts for mental health service delivery administered through the federally sponsored Indian Health Service. Recommendations for mental health professionals who desire to avoid a subtle but profound Western cultural proselytization in their therapeutic service to Native clients and their communities are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
论延光四年佛像的史学意义 总被引:1,自引:0,他引:1
长江三峡出土的延光四年摇钱树佛像,是目前所知的中国第一尊古佛像。该佛像举右手施无畏印,高肉髻,与四川其他各摇钱树大致属于同一类型。惟该佛像身着交领衣,显示了当时中国信众对佛像仪轨并不十分熟悉,是佛像初传中国时期的常有现象。就中印两国佛像艺术传播与交流的角度看,这尊佛像,作为一个有力的证据,可以缩小古印度佛像初创时期的争议范同,也可以缩小贵霜王朝迦腻色伽即位年代的争论范围,对探究佛教造像在古印度的起源有重大意义。同时,该佛像可以证明中国古籍记载的早期佛教造像虽有夸饰之词却是有事实依据为基础的。 相似文献
10.