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61.
Pranab K. Roy Chowdhury Jeanette E. Weaver Eric M. Weber Dalton Lunga St. Thomas M. LeDoux Amy N. Rose 《International Journal of Digital Earth》2020,13(1):119-135
ABSTRACTUrban areas presently consume around 75% of global primary energy supply, which is expected to significantly increase in the future due to urban growth. Having sustainable, universal energy access is a pressing challenge for most parts of the globe. Understanding urban energy consumption patterns may help to address the challenges to urban sustainability and energy security. However, urban energy analyses are severely limited by the lack of urban energy data. Such datasets are virtually non-existent for the developing countries. As per current projections, most of the new urban growth is bound to occur in these data-starved regions. Hence, there is an urgent need of research methods for monitoring and quantifying urban energy utilization patterns. Here, we apply a data-driven approach to characterize urban settlements based on their formality, which is then used to assess intra-urban urban energy consumption in Johannesburg, South Africa; Sana’a, Yemen; and Ndola, Zambia. Electricity is the fastest growing energy fuel. By analyzing the relationship between the settlement types and the corresponding nighttime light emission, a proxy of electricity consumption, we assess the differential electricity consumption patterns. Our study presents a simple and scalable solution to fill the present data void to understand intra-city electricity consumption patterns. 相似文献
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63.
针对当前铁路运营的实际情况,设计并实现了基于MSP430F13x系列单片机的货车防盗报警系统.详细介绍了系统的原理和软、硬件设计.系统在货车遭遇破封的情况下触发报警器,并将报警信息以无线电信号发射出去.接收机接收报警信息并将其在LCD上显示出来,以便民警即时处理.经实际应用证明系统性能良好. 相似文献
64.
温度和盐度对埋栖性双壳类泥蚶(Tegillarca granosa) 呼吸、排泄的影响 总被引:1,自引:0,他引:1
在人工条件下采用静水封闭呼吸瓶的方法研究了温度、盐度对泥蚶(Tegillarca granosa)呼 吸、排泄的影响, 并综合分析了温度、盐度交互作用对呼吸、排泄的影响程度, 为泥蚶基础生物学研 究积累了资料。结果表明, 在设定的不同温度条件下泥蚶耗氧率变化范围0.63-4.47mg/(g·h), 单因 素方差分析结果显示4 个盐度条件下泥蚶耗氧率的差异均极显著(P<0.01); 排氨率的变化范围 123.11-955.68μg/(g·h), 排氨率受温度的影响也均极显著(P<0.01); 经回归发现, 在温度13-31℃ 范 围内, 耗氧率和排氨率均与温度的变化呈显著的指数相关。除温度为18℃ 时, 其它各温度条件下, 不同盐度梯度间的耗氧率差异不显著(P>0.05), 盐度对排氨率影响的变化趋势不一致。在温度 (13-31℃)和盐度(18-28)时, 温度和盐度对耗氧率、排氨率的影响均存在交互作用, 耗氧率(Y)、排 氨率(Y)与温度(T)和盐度(S)之间的二元线性回归关系为Y=a+bT+cS+dT×S.泥蚶呼吸排泄的O:N 比 在4.50-13.07 之间, 平均值为7.16.泥蚶呼吸排泄的代谢活动受温度、盐度的影响显著。 相似文献
65.
《Marine Policy》2015
The limited precious coral (Coralliidae) resources in the Northwestern Pacific have been managed by Taiwan with a comprehensive management plan, by Japan with a strengthened set of management measures, and by China through the listing of such coral as a Category I national treasures. However, continuous increases in coral consumption and coral prices have stimulated overexploitation and poaching of the resource, and hence have undermined the effectiveness of these management schemes. This article discusses the current precious corals supply chain and suggests that the rise of China in purchasing substantial amounts of coral products was the underlying cause for overexploitation and poaching. Several gaps in the management schemes are also identified and discussed. The article finally concludes that there is an urgent need for establishing a cross-disciplinary integrated conservation policy and a regional management platform consisting of the three participating states to address all the relevant social and ecological issues. 相似文献
66.
《Marine Policy》2015
Portugal has the third highest seafood consumption per capita in the world and current patterns of seafood consumption are linked to how seafood products were embodied in the Portuguese society. The objective of this research is to understand Portuguese seafood consumption's main drivers and its consequences. For that official statistics were analyzed and a literature review on seafood consumption was undertaken. Portuguese seafood consumption is characterized by a wide diversity of species and preparing modes, when compared to other countries in Europe. Cod (salted and dried), does not exist in Portuguese waters but due to several factors, such as politics, religion and tradition, became the main species in Portuguese seafood consumption, representing around 38% of the national seafood demand. Five drivers are suggested to explain why Portuguese eat so much seafood: geography, marine resources, fisheries, social forces and politics; and consequences for the environment, economy and health are discussed. Hence while most dietary recommendations advise an increase in fish consumption is not applicable to Portugal and a more sustainable seafood consumption for the future is advocated. 相似文献
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68.
Zn2+对日本沼虾(Macrobrachium nipponensis)的急性致毒效应 总被引:1,自引:0,他引:1
在水温(27.4±1.3)℃条件下,以体长(33.23±1.66)mm、体质量(0.7893±0.1518)g的日本沼虾为实验动物,采用静水停食法开展了Zn2+对日本沼虾的急性毒性实验,并以此为基础,测定了Zn2+不同质量浓度水平下日本沼虾的耗氧率与窒息点.结果表明:(1)Zn2+对日本沼虾的急性致死效应与其呼吸生理代谢受阻密切相关;(2) Zn2+对日本沼虾24h、48h、72h、96h的半致死质量浓度依次为1.493、0.844、0.643和0.464mg/L; (3) Zn2+对日本沼虾昼均、夜均和日均耗氧率均无显著影响的阈值为0.046mg/L,该值为Zn2+对日本沼虾急性毒性的安全质量浓度;(4) Zn2+对日本沼虾产生轻度胁迫和中度胁迫的质量浓度范围分别为0.046-0.064mg/L和0.064-0.082mg/L. 相似文献
69.
石油天然气钻井肩负着油气资源勘探开发的国家使命和社会责任,同时又是能耗大户,节能潜力和责任很大。企业的科学发展当责无旁贷的把节能减排看作转变经济发展方式、节能挖潜、降本增效的重要抓手。只有坚持低碳生产,坚持节约发展、清洁发展、安全发展,才能实现企业又好又快地发展。 相似文献
70.