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811.
The data on the coal production and consumption in Jilin Province for the last ten years were collected,and the Grey System GM( 1,1) model and unary linear regression model were applied to predict the coal consumption of Jilin Production in 2014 and 2015. Through calculation,the predictive value on the coal consumption of Jilin Province was attained,namely consumption of 2014 is 114. 84 × 106 t and of 2015 is 117. 98 ×106t,respectively. Analysis of error data indicated that the predicted accuracy of Grey System GM( 1,1) model on the coal consumption in Jilin Province improved 0. 21% in comparison to unary linear regression model.  相似文献   
812.
This article focuses on the reciprocal effects that exist between the physical environment and the social interactions between ethno-cultural groups in disadvantaged neighbourhoods. Biographical narrative interviews and mental map analyses were carried out with German and Turkish residents in two disadvantaged neighbourhoods in Germany to define the resident's own experience of their physical surroundings.The findings of the research verify that the changes in the environment were not only physical and structural changes: they also led to changing identities having a symbolic meaning for the established German residents. As the Turkish residents work to create a sense of identity, the established residents view these changes more as a threat than as an enrichment. They do not so much feel threatened by the cultural differences between the groups, but they sense that their own `old-time' German socio-cultural position could be affected by the establishment of Turkisch residences and institutions in `their' neighbourhood. The empirical research revealed differences in the ethno-cultural perceptions between Duisburgh-Marxloh where there is a pronounced small-scale segregation between the groups, whereas there is a small-scale mix of different ethnic groups even at the block level in the other area investigated in Wuppertal-Osterbaum. Although both areas have a high percentage of ethnic minorities the small-scale mix in Wuppertal-Ostersbaum seems to have prevented a polarisation in the population.  相似文献   
813.
Effects of temperatures and salinities on oxygen consumption and ammonia-N excretion rate of clam Meretrix meretrix were studied in laboratory from Oct. 2003 to Jan. 2004. Two schemes were designed in incremented temperature at 10, 15, 20, 25℃ at 31.5 salinity and in incremented salinity at16.0, 21.0, 26.0, 31.5, 36.0, and 41.0 at 20℃, all for 8-10 days. From 10 to 25℃, both respiration and excretion rate were increased. One-way ANOVA analysis demonstrated significant difference (P〈0.01) in physiological parameters in this temperature range except between 15 and 20℃. The highest Q10 thermal coefficient value (12.27) was acquired between 10 and 15℃, and about 1 between 15 and 20℃, indicating M. meretrix could well acclimate to temperature changes in this range. Salinity also had significant effects on respiration and excretion rate (P〈0.05). The highest values of respiration and excretion rate of M. meretrix were recorded at 16.0 salinity (20℃). These two physiological parameters decreased as salinity increased until reached the minimum Q10 value at 31.5 (20℃), then again, these parameters increased with increasing salinity from 31.5 to 41.0. M. meretrix can catabolize body protein to cope with osmotic pressure stress when environmental salinity is away from its optimal range. No significant difference was observed between 26.0 and 36.0 in salinity (P〉0.05), suggesting that a best metabolic salinity range for this species is between 26.0 and 36.0.  相似文献   
814.
Numerical data based on stomach content analysis of the zooplanktivorous freshwater fish, Retropinna semoni, were used to examine the effect of fish sample size on mean counts of dominant prey items. Fifty adult R. semoni were collected from throughout the open‐water of Lake Benanee, Australia at each of five times over a diel period. Bootstrapping was used to generate confidence intervals around sample means, and markedly more accurate means were obtained from samples collected in the day than the night. High variation in night samples was the by‐product of a diurnal feeding regime. Traditional sample sizes of 10 to 15 stomachs resulted in reasonable confidence intervals of sample means derived from collections on the first day, corresponding to uniform feeding patterns in the population. However, increased sample sizes were required to describe more complex feeding behaviour on the second day, when a proportion of the population switched to an alternative prey source.  相似文献   
815.
李永福 《北京测绘》2014,(5):130-133
通过对北京市基础测绘和房屋修补测工作内容的介绍,简述了在城市的发展建设过程中基础测绘与房屋普查修补测的区别与联系。基础测绘是一切测绘工作的基础,它的发展不但可以进一步拓宽其业务领域的服务范围,促进基础测绘成果的广泛应用,还可以更好地促进基础测绘的发展。  相似文献   
816.
基于GIS的保障性住房选址的决策因素分析   总被引:1,自引:0,他引:1  
保障性住房的合理选址关系到被保障人群的生活质量和社会发展的稳定性,其决策因素的分析对保障性住房选址有着重要建设性意义。本文根据我国保障性住房空间选址特点,从就业保障、居住分异、公共服务配套设施完善度、经济发展等角度分析影响其选址的决策因素,然后,运用多因素综合评价法,结合层次分析和熵权系数法,建立保障性住房选址合理性评价模型,并利用GIS空间分析平台,以武汉市百步亭社区为例进行实证研究。研究结果表明,百步亭社区作为保障性住房社区选址具有较高的合理性;所选决策因素能够较好地评价选址的合理性,为今后的保障房选址决策提供参考。  相似文献   
817.
1 IntroductionIn natural conditions, field water surplus or deficit is different between field water requirement and field water supply by nature. Field water requirement can be expressed either as potential field evapotranspiration or as crop water requirement. Potential field evapotranspiration is also called reference crop evapotranspiration which is defined as "the rate of evapotranspiration from an extensive surface of 8 to 15 cm tall, green grass cover of uniform height, actively growing…  相似文献   
818.
基于2018年早春和夏季长江口邻近海域的调查数据,分析溶解氧(DO)的时空分布,并讨论其影响因素.结果表明,夏季DO浓度变化范围为1.58~9.37 mg/L,浮游生物光合作用产生的DO是夏季表层水体过饱和的主要因素;夏季调查海域受台湾暖流北上引起海水层化加强,同时水体富营养化导致表层生物大量繁殖所引起有机碎屑的沉降和耗氧分解作用是底层低氧区存在的主要因素.夏季在台湾暖流影响下底层水体表观耗氧量(AOU)与营养盐成正相关关系,底层有机物耗氧降解过程与营养盐的再生密切相关.早春DO浓度变化范围为7.90~10.1 mg/L,长江口外北部海域和浙江近岸海域海水混合均匀,DO浓度主要受温度控制,而台湾暖流影响区海水出现层化现象,其低DO含量也为低氧区的形成奠定了基础.  相似文献   
819.
章新福 《东北测绘》2014,(1):221-222,225
主要通过大量房屋分摊面积、分摊系数的计算实例,由传统的房屋分摊面积、分摊系数计算方法,推导出简便实用的、准确的分摊面积、分摊系数计算公式;通过实用简便的分摊面积、分摊系数计算公式,可直接准确地计算出房屋各套内的分摊面积,分摊面积计算工作由繁锁变为简便准确,节省大量工作时间。  相似文献   
820.
Electricity is one of the most important components in energy consumption, which is directly related to economic growth, CO2 emission and global warming. This research intends to estimate spatial distribution of electricity consumption in China, the largest developing country, and analyze the temporal and spatial change of electricity consumption during 1994–2009. The spatial modeling is based on the total electricity consumption of each province and DMSP (Defense Meteorological Satellite Program) – Operational Line-scan System (OLS) data, the latter provides the nighttime light information corresponding to electricity consumption, GDP and population. A simple method was developed to correct the saturated pixels with digital number of 63 in non-radiance-corrected DMSP-OLS data, using cities’ GDP data. The spatial electricity consumption maps were produced during 1994–2009, and they were validated by the electricity consumption records of 101 cities. Finally, the spatial–temporal changes of electricity consumption were analyzed. The results of this research can help to understand the regional discrepancy, especially rural and urban areas of China, of electricity consumption and economic development.  相似文献   
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