浅谈数学教学在中职学生自信教育中的应用

现代的教育必须是动态的、不断变化的,但无论怎样努力都是为了实现激发学生的内在积极性、使学生的个性和能力得到充分发挥,并且具备良好的心理条件、掌握应有的技能水平、学会正常的待人接物,满足当代社会的需求。     

管理人员流失问题研究——以新农开发股份有限公司为例

以新农开发股份有限公司为例,介绍了企业人才流失的现状,基于马尔科夫链模型分析了人才流动趋势,基于马斯洛需求层次理论分析了人才流失的主要原因,并提出了相应的解决对策。     

社会学视角下农村成年居民阅读需求的调查研究——基于广东省三镇的调查

[目的/意义]阅读是一种社会活动,在社会学理论框架下对农村成年居民的阅读需求进行分析,不仅能了解不同的社会人群阅读需求的差异,还能理清社会学因素与农村居民阅读需求的相互影响关系。[方法/过程]文章面向广东省三镇的农村居民,通过问卷调查,运用统计学方法分析社会学因素中的个人、家庭、社会中的某些因素对农村成年居民阅读需求的影响,并据此提出满足农村居民阅读需求的策略。[结果/结论]认为应该从优化资源结构、保障居家阅读、提升家庭阅读氛围,完善农家书屋的建设4个方面改进服务质量,优化农家书屋服务。     

The impact of a hydroelectric dam on Neotropical fish communities: A spatio-temporal analysis of the Trophic Upsurge Hypothesis

We employed the trophic upsurge hypothesis as an analytical framework to describe the response of Neotropical fish communities to terrestrial inundation associated with river damming. Data were collected for the impact assessment of the Peixe Angical Dam, Tocantins River, Brazil. Monthly surveys were conducted at nine sites (seven upstream, two downstream) from 15 months before to 20 months after dam closure and a follow-up survey 60–83 months after closure. Fish responses differed in timing and magnitude across sites. In the new reservoir, populations peaked 8–13 months after flooding, demonstrating increases in richness (84 ± 52%), biomass (329 ± 266%) and abundance (681 ± 348%) with the maxima for richness and abundance tending to precede biomass maxima. Populations of all families increased but were greatest for Engraulidae, Hemiodontidae, Serrasalmidae and Characidae, and lower for the benthic catfish: Sciaenidae, Dorididae, Pimelodidae. Downstream populations peaked 5–12 months after closure or showed consistent decline. Five years after dam-closure richness and abundance were lower compared to predam levels, with populations at all sites demonstrating an ongoing decline. Reservoir creation triggers reproductive recruitment and otherwise pools spatially disparate populations from across the flooded valley. If the rise in richness is largely explained by the increased catchability of species otherwise present prior to flooding, it may be more appropriate to estimate species loss with reference to upsurge data. As peak biomass coincides with declining richness, modelling fisheries production from annually aggregated data may risk overestimating the potential for sustainable harvests. Upsurge–response curves can help identify the timing of critical ecological thresholds for flood-managed fisheries.     

Flow‐mediated movement of freshwater catfish,Tandanus bostocki,in a regulated semi‐urban river,to inform environmental water releases

Movement and migration of fish are critical for sustaining riverine fish populations. Water resource development alters natural flow regimes and can disconnect habitats and interfere with hydrological cues for fish movement. Environmental flow releases can counter these impacts, but to be effective they must be based on quantitative flow–biota relationships. We used radio‐telemetry to investigate the association between flow and movement of Tandanus bostocki, a plotosid fish endemic to south‐western Australia. Movement was assessed for 15 adult fish at three temporal scales: weekly, daily and bihourly to reveal seasonal patterns in movement, movement around individual flow pulses, and to describe changes in home range respectively. We used a predictive modelling approach to assess the importance of discharge and other covariates on the directional distance travelled or linear home range size. Our seasonal and flow pulse study revealed that T. bostocki undertook larger downstream movements during higher flows and smaller upstream movements during lower flows. Daily movements tended to be downstream on the ascending limb of flow pulses and upstream on the descending limb. Flow‐dependent movements at weekly or daily time scales were relatively modest (typically hundreds of metres) and were moderated by time of year and gender; however, fish underwent a synchronised 1‐km movement upstream during the known reproductive period in October. The home range study revealed that T. bostocki had larger home ranges (night‐time foraging) when baseflow was elevated. These results can assist the design of customised environmental flows in the study river and other flow‐regulated rivers.     

Use and Management of Poor Quality Waters for the Rice-Wheat Based Production System

Summary

India's major improvements in food production have been made possible via a shift towards rice-wheat systems as a consequence of enhanced utilization of ground waters. Rice-wheat rotation covering 10.5 million ha contribute about 75 percent of total food production. But it is being observed now that yield increases in rice and wheat has slowed down and there is rather a decline in factor productivity. One of the major reasons for this decline is indiscriminate use of alkali waters constituting about 25-42 percent of ground waters surveyed especially in the northwestern states of the Indo-Gangetic Plains (IGP). Because of high water requirements of the system, sodication rates of soil being irrigated and their steady state pH and sodicity values are much more (about 1.8 times) than that of the low water requiring rotations like millet/maize-wheat. So there has been a dilemma on whether or not rice-wheat system should be advocated with alkali irrigation waters. Consistent research efforts have lead to the guidelines for irrigation with such waters with respect to their amendment needs (gypsum requirements, frequency and mode of application), conjunctive use with canal waters and use of organic materials and chemical fertilizers, etc. These results do show that subject to the following of specific soil-water-crop management systems, it is possible to control the build up of sodicity in soils and sustain crop yields. Options available in terms of management practices and some of the researchable issue are discussed in this paper.     

大学校园绿地交往空间设计初探

针对校园绿地中的交往空间展开研究，在学生行为心理的调查基础上，从交往活动：集会、小型体育活动和闲坐聊天探讨满足学生行为需求的校园绿地交往空间设计。     

基于农户视角的橡胶生产技术应用及需求分析——以海南琼中黎族苗族自治县营根镇为例

利用海南琼中14个村委会15个代表性植胶农户的调查数据分析农户的技术应用及需求，并从农户的视角评价科技推广工作。从农户的技术应用、科技推广工作评价、农户的技术服务需求等3个方面进行分析。结果表明：该地区橡胶生产以青壮年劳动力为主，橡胶种植历史不长；农户橡胶栽培割胶技术仍以传统经验为主；胶园抚育管理差和割胶技术水平低是农户认为影响胶园产量的主要因素；割胶技术总体上处于中等偏下水平；农户技术需求重点是胶园抚育管理、死皮复割、根病防治和割胶技术。     

Agroforestry and soil conservation needs of smallholders in Southern Zambia

An agroforestry and soil conservation needs assessment survey conducted in southern Zambia revealed valuable insight into needs, constraints and development options as perceived by smallholders themselves. Inadequate efforts to conserve soil are due to technical and socio-economic factors, they do not result from a lack of awareness of the widespread erosion threat. Fruit tree planting, windbreak establishment as well as the protection of the natural Faidherbia albida regeneration in cropland are popular agroforestry interventions whose positive effects are widely acknowledged. Forty-two perennial species were found to directly contribute to people's diet. Although local fuelwood and fodder shortages as well as the need for fencing are recognized only few respondents envisage agroforestry solutions such as fuelwood and fodder tree planting or live fencing. Most smallholders are interested in tree planting but have so far only planted few trees. Those planted are usually exotic fruit trees. Drought hardly, termite and browse resistant perennials adapted to smallholder tree planting must be provided by the extension services. The widespread exclusion of women from decision making and the lack of tenure security hampers female participation in agroforestry development and consequently threatens sustainable development altogether.