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891.
892.
The key to agricultural development in the eastern region of India, where problems of excess water and water scarcity coexist, is the scientific management of water resources with the adoption of recommended water-management technologies. A vast networking of infrastructure for the development and dissemination of water- management technologies have been designed since the very inception of planned economic change. Despite these concerted efforts, a large number of recommended technologies are either being adopted in piece-meal or not at all. The research and extension systems have been generating and disseminating technologies, therefore, it was felt worthwhile to assess the feasibility and appropriateness of recommended tecnologies as perceived in the first instance by the personnel of the research system and followed by the extension personnel. These steps were felt to be a precursor to screen the recommended technologies for their dissemination and evaluation in different farming systems. The assessment of recommended water-management technologies was performed after their documentation from different organisations working in the field of water management in two eastern India states viz. Orissa and West Bengal. The perception of 30 personnel members of the research system regarding the feasibility of these technologies elucidated that out of 86 documented recommended water-management technologies, 40 were having feasibility scores of ≥ 4.0; 8 technologies with score £ 3.0 and the rest of the 38 technologies with a score between 3.0 and 4.0 on a feasibility continuum range from 1.0 (not feasible) to 5.0 (highly feasible). Out of 40 recommended technologies (already assessed as highly feasible by the research personnel), extension personnel have perceived 16 and 10 technologies as highly appropriate and feasible, respectively. While six and four technologies were found to be less appropriate and feasible, respectively. Correlation of all nine indicators of appropriateness with feasibility of technologies was significant. Five indicators of appropriateness viz. simplicity, physical compatibility, production sustainability, cultural compatibility and cost together constituted 36.8 per cent of the total variation in feasibility with the ‘t’ values and ‘F’ values being significant. It indicates that not appropriateness of technologies alone but other factors influence the feasibility of technologies.  相似文献   
893.
1. Introduction Initial-value problems (IVP) for the differential equations are often confronted with in many fields of science, and are particularly common in engineering. These problems are characterized by a governing differential equation and its associated initial conditions. Methods for solving direct IVP have been known for many decades in the area of differential equation. A few of the more popular methods of solution have proven to provide sufficient and even efficient mechanisms …  相似文献   
894.

Employability is an increasing concern for university students. Our survey set out to examine university students’ perceptions of their employability and the ways in which these perceptions relate to positions that subsequently connect students to working life: students’ self-representational position or “ability self”, and students’ life-historical positions such as chosen field of study, phase of degree and working life experience. The participants comprised a sample of students (N = 1819) from two Finnish universities, representing diverse fields of study. It was found that apart from the field of study, the perceived proximity to graduation and working life was associated with the perception of employability. Furthermore, a set of self-attributed capabilities was associated with students’ perceptions of employability, particularly extroversion, ambitious competitiveness, mental strength and the desired characteristics of a good employee; however, the attribution of academic skills showed opposing effects. It was concluded that both self-representational and live-historical positions are part of the construction of students’ optimism regarding their employability.

  相似文献   
895.
This article introduces emergent memory, a conceptual extension to rhetorics of public memory, to describe memory’s genesis in sites built without commemorative commitments. Examining Detroit’s “8 Mile Wall,” a site built to reinforce segregated housing, this project argues the rhetorical tenets of emergent memory present in this space. As a relic of segregated history, the wall symbolically recalls the city’s controversial past, but has recently been the subject of a local mural project to redefine the wall’s purpose. Some consider this a step toward reclamation, as it visually repositions the disturbing remnant. For others, the murals simply cannot overwrite troubling memories of the city’s discriminatory history. This essay uses emergent memory to describe how the wall’s complicated mnemonic legacy simultaneously harkens to a difficult history and how the mural additions use that same legacy to convey an optimistic future for Detroit and those marked by this urban space.  相似文献   
896.
The aim of this study was to compare the somersaulting techniques used in the 16 highest-scoring and 16 lowest-scoring Roche vaults. Our hypothesis was that the gymnasts performing the highest-scoring Roche vaults would demonstrate a better technique than those performing the lowest-scoring Roche vaults while on the horse (pushing off the horse more effectively), somersaulting (executing most of the required somersaults higher in flight), and landing (showing a greater control). A 16-mm motion picture camera, operating at 100 Hz, recorded the vaults during the official competition. The two-dimensional direct linear transformation was used for spatial reconstruction. The results of t-tests (P < 0.05) indicated that, compared with the low-scoring gymnasts, the high-scoring gymnasts had: (1) greater height of body centre of mass and a more fully extended body position at the horse take-off; (2) greater height of body centre of mass at the peak of post-flight, knee release, and touchdown on the mat; (3) greater horizontal and vertical displacements of body centre of mass, greater somersaulting rotation, and longer time from the knee release to mat touchdown; and (d) markedly smaller landing point deductions. In conclusion, a successful Roche vault is likely when the focus is on: (a) leaving the horse with a large vertical velocity in an extended body position to achieve a high trajectory of centre of mass by first extending the legs, then immediately pushing off the horse vigorously, using the muscles of the upper extremity; (b) grasping the knees immediately after the take-off from the horse, achieving the tightly tucked body position early during the ascent to the peak, and completing two-thirds of the required somersaults at a great height; (c) releasing the knees and extending the body above the top level of the horse; and (d) contacting the mat with a high body centre of mass position.  相似文献   
897.
898.
OBJECTIVE: The prevalence of childhood sexual abuse among Latino adult men who have sex with men who live in the US was estimated because a history of childhood sexual abuse increases HIV sexual risk behaviors and other negative health outcomes in adulthood. METHOD: The Urban Men's Health Study is a random-digit telephone probability survey of 2881 adult men who have sex with men (MSM) aged 18 years or older residing in San Francisco, New York, Los Angeles, and Chicago. Self-reported history of childhood sexual abuse was the main outcome measure gathered from 2692 MSM. RESULTS: A significantly higher proportion of Latino MSM reported sexual abuse before age 13 (22%) than did non-Latino MSM (11%). CONCLUSIONS: Latino MSM are twice as likely to report a history of childhood sexual abuse than are non-Latino MSM. Given the association between childhood sexual abuse and increased risk for HIV and other negative health outcomes, health providers must remain vigilant to the possibility of childhood sexual abuse histories among their Latino patients.  相似文献   
899.
从“学生投入”的角度,对体育教学中普遍存在的学生外显的积极行为和内隐的消极心理这一矛盾进行深入分析,认为体育教学应该重视学生积极情感的投入,减少遵守规范式和消极情感式的情感投入;重视学生积极性的认知投入,减少表面性的认知投入;重视学生积极的行为投入,减少消极的行为投入。  相似文献   
900.
掷标枪技术训练要从基础训练阶段(13~15岁)抓起。通过实验对照分析找出一个较为理想的符合该年龄段特点的掷标枪技术训练的计划安排和练习方法,以及该年龄段掌握技术的要求。  相似文献   
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