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171.
Vertical chain collaboration is a strategy for customers’ value creation. However, Dutch fishermen are hardly participating in integrated value chains. While supply chain literature describes factors that contribute to successful chain partnerships, scarce research has been done on the dynamics of the sociocultural context for chain collaboration.In 10 semi-structured interviews, representatives of supply chain parties were asked for their perceptions on chain collaboration, trust, and the role of the local community. The interviews were directed at obtaining so-called ‘tacit’ knowledge, the non-spoken codified truths of social networks. Without generalizing, this research provides benchmarks to monitor how the different domains, laid out in this study, impact chain collaboration: community values, network participation and company competences. An overview is given of socio-economic factors blocking and enhancing chain collaboration at company and community level. Factors such as the strong bonding of family with business in tightly knit networks, a high level of social control, entrepreneurial autonomy, and loyalty as community norm hamper collaboration within the supply chain.Respondents’ discourse demonstrates that cultural codes and identity form the very core of the entrepreneur, driving rather than ‘embedding’ economic behavior. Kinship, religion and peer pressure determine ‘windows on the world’ when engaging in chain collaboration. Consequently, any analysis of economics that does not integrate sociological and psychological methodology is flawed from the outset.  相似文献   
172.
We can collect, store, and analyze a huge amount of information about human mobility and social interaction activities due to the emergence of information and communication technologies and location-enabled mobile devices under cyber physical system frameworks. The high spatial resolution of population data on a multi-temporal scale is required by transport planners, human geographers, social scientists, and emergency management teams. In this study, we build a space-time multiple regression model to estimate grid-based (500 m × 500 m) spatial resolution at multi-temporal scale (30-min intervals) population data based on the space-time relationship among geospatially enabled person trip (PT) survey data and incorporate both mobile call (MC) and geotagged Twitter (GT) data. Since using geospatially enabled PT survey data as dependent variables enables us to acquire actual population amounts, which strongly depend on MCs and social interaction activities. Although many grids have a strong correlation between PT and MC/GT, some show fewer correlation results, especially where the grids have factories, schools, and workshops in which fewer MCs are found but a large population is presented. Although GT data are sparser than MCs, people from amusement and tourist areas can be detected by GT data. The space-time multiple regression model can also estimate the different amounts of populations based on human travel behavior that changes over space and time. According to accuracy assessments, the night-time estimated results, especially between 00:00 and 06:30, strongly correlate with national census data except in places where the grids have railway and subway stations.  相似文献   
173.
This focus section explores what it means to think geographically about an emergent Asia. The four articles are based on presentations given at the Presidential Plenary session at the 2013 Association of American Geographers annual meeting in Los Angeles. In this Introduction, I briefly examine the temporalities associated with the term emergent and the spatialities evoked by the label Asia, arguing that mainstream conceptions of emergence, as progress into the light, and territorial conceptions of Asia require critical reflection from the perspective of contemporary geographical thought. These issues are taken up in the subsequent articles, examining when is Asia, the U.S. role in constructing representations of Asia, the Japanese origin of global supply chains, and the question of whether Western urban theory suffices to account for urbanization in China.  相似文献   
174.
Reducing large-scale deforestation in commodity frontiers remains a key challenge for climate change mitigation and the conservation of biodiversity. Public and private anti-deforestation policies have been shown to effectively reduce forest loss, but the conditions under which such policies get adopted are rarely examined. Here we propose a set of conditions that we expect to be associated with the adoption of effective anti-deforestation policies in commodity frontiers. We then examine whether these conditions have influenced policy adoption in South America’s major soy-and-cattle frontiers: the Brazilian Amazon, the Cerrado, the Chaco, the Chiquitano, and Paraguay’s Atlantic Forest. By collating empirical data from diverse sources, including literature review, extensive expert interviews, and analysis of primary and secondary data, we show that the Cerrado, the Chaco, and the Chiquitano differ from the Brazilian Amazon in multiple ways that might have inhibited adoptions of effective anti-deforestation instruments. These conditions include: a higher importance of the agricultural sector within the respective countries, lower carbon stocks and species richness, higher prevalence of private land tenure, and higher baseline compliance with forest reserve regulations on private lands. We also observe that the adoption of the most effective private anti-deforestation instrument, commodity moratoria, may respond to similar conditions as those influencing the adoption of public instruments. Incentivizing public and private actors to adopt effective anti-deforestation policies in the Cerrado, Chaco, and the Chiquitano will likely be more challenging than it has been in the Brazilian Amazon.  相似文献   
175.
在实验室条件下,研究铜在海水及以扁藻、轮虫、对虾等生物组成的食物链中的积累与传递规律。结果表明,各种海洋生物都能直接从海水中吸收铜,铜可沿着海水→扁藻→轮虫→仔虾传递。文章还探讨了本食物链各环节积累铜的主要途径以及影响生物个体铜的累积量的诸因素。  相似文献   
176.
多点系泊下后弯管波力发电浮体模型试验研究   总被引:1,自引:5,他引:1  
在大型造波水池中,对最佳后弯管浮体模型3-3,进行了多点系泊下浮体模型试验研究。测定了该模型在不同系泊条件下,气室平均输出气流功率随波周期的变化曲线NA-T,最大锚泊力与入射波高之比随波周期的变化曲线Fmax/Ho-T和最大纵荡距离与入射波高Ho之比随波周期变化曲线Xmax/Ho-T。选定L型链三点系泊为最佳系泊方案。进行了不同喷嘴比的性能试验和不类来波方向的试验,测定了浮体波能转换性能、最大锚泊力、最大纵荡距离随来波方向的变化。  相似文献   
177.
From 1979 to 1989, the current Qingshuigou course of the Huanghe River formed a sub - delta which resembles a beak extending into the Laizhou Bay. It covers 618 km2 in area. To meet the needs of developing and constructing the Huanghe River Delta and under the presupposition of keeping the current course for 15-20 a, we forecast mainly by using the OM (1, 1) model that the front border of the sub-delta will be close to 119°30'E and its area will become 923 km2by the end of the year 2000. The Huanghe River will make land 760 km2 in area.  相似文献   
178.
设计合成一种尚未见文献报道的酚醚型双臂开链冠醚化合物L(L=2,6-二(8’-喹啉氧甲基)-4-甲基-苯甲醚),经元素分析、IR、1HNMR、MS等方法确定了其组成和结构。其Ag(Ⅰ)、Cu(Ⅱ)、Ni(Ⅱ)固体配合物的元素分析结果表明金属离子不同,则其配合物的配位比(M∶L)不同,Ag(Ⅰ)配合物为1∶1,Cu(Ⅱ)、Ni(Ⅱ)配合物为2∶3。并运用热重-差热分析对其热稳定性进行初步研究。  相似文献   
179.
Calmodulin is a calcium binding protein that modulates the activity of diverse groups of protein including some protein kinase, adenylate cyclases and ATPase. Here we use the total DNA of Sonneratiaparacaseolaris as the template ofthe polymerase chain reaction (PCR). The PCR primers have been designed and synthesized according to the 5-and 3-terminal oligonucleotide sequences of Calmodulin gene of plants in Genbank and ligated with cloning vector pBsk( ).The recombinant clones have been obtained from the selected medium. The results of DNA sequences analysis show that the nucleotide sequences of ORF share more than 85% homologies as compared with those ofcalmodulin genes of several other plants. Similar to rice and apple, the ORF is interrupted by an intron behind the 75th nucleotide.  相似文献   
180.
红树植物拟海桑钙调蛋白基因的克隆及分析   总被引:1,自引:0,他引:1  
熊玲媛  林涛  周涵韬  徐金森  葛运生  陈睦传  陈亮 《台湾海峡》2002,21(2):193-198,T002
钙调蛋白(Calmodulin)是生物细胞内一种重要的调控蛋白,通过其与靶酶的相互作用控制细胞正常的生长和发育,作者以高抗盐红树植物海桑属拟海桑(Sonnera-tia paracasolaris)总DNA为模板,参考GenBank上植物钙调蛋白基因序列合成5′端和3′端引物,利用多聚酶链式反应(PCR)扩增了拟海桑钙调蛋白基因,与克隆载体pBsk( )重组,转化Escherichia coliDH5α得到重组克隆子,DNA序列分析表明,所得片段的编码区在核苷酸序列上与迄今已知的几种植物钙调蛋白基因有很高的同源惺 ,同源率在85%以上;与水稻、苹果,衣藻等相似,其基因编码区被一个位于第75位核苷酸之后的内含子所中断。  相似文献   
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