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排序方式: 共有306条查询结果,搜索用时 15 毫秒
1.
Sammi Wae Ki WONG 《景观设计学(英文)》2022,10(4):84
Prompted by increased domestic and transnational demand for Pu’er tea, an emergence of agroecosystem intensification in Southern Yunnan, China has resulted in various agro-ecosystems including tea forests, mixed crop systems, and monocultural terrace tea gardens, in the tea production system. Plants of Camellia sinensis assamica often grow as trees in forests whilst C. sinensis sinensis grow as shrubs in terrace tea gardens. Inspired by the wine industry, the concept „Terroir” acts as a framework that analyzes both environmental and human factors yielding var ying botanic profiles, and hence quantifies values created by the cultivation process. The approach allows economic opportunities of place-based tea products to be driven by the origin in lieu of extrinsic qualities, which has resulted in to the fabricated reputation of terroir. In response to a common gap in terms of botanical and cultural values between tea cultivation and marketing trends, this artic le investigates an alternative scenario in which tea production and promotion model could minimize its environmental impacts and utilize its economic weight to advance land conservation efforts specific to cultural complexity at community scales. 相似文献
2.
S. H. WONG MS BSc CBiol MIBiol C. C. CHOI BSc CEng MIChE MAIChE MHKIE 《Water and Environment Journal》1989,3(1):75-81
A n existing aetated lagoon treating piggery waste was converted into an aerobic sequencing batch reactor (SBR). After the commissioning period, the SBR plant treated piggery wastewater containing BOD and suspended solids (SS) concentrations of 2881 mg/l and 1419 mg/1 respectively, producing an effluent having an average BOD and SS of 18.7 mg/1 and 12.3 mg/1 respectively. The volumetric loadings on the SBR and the process were similar. However, the SBR process operated at a lower mixed liquor suspended solids (MLSS) concentration and shorter sludge retention period. Although the capital and operating costs of the SBR are higher than for the aerated lagoon, the simplicity of operation, the high BOD and SS removal efficiency, and the small land requirement make this type of process an attractive treatment option, particularly in places where land supply is limited and expensive. 相似文献
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钢-混凝土组合薄壳屋盖(Comshell屋盖体系)由兼作永久模板并替代钢筋的薄壁加劲钢底壳和现浇混凝土两部份组成。薄壁钢底壳由模块化单元件通过螺栓连接而成,单元件呈无盖扁盒状,由底板及周边板组成。其周边板在钢壳上构成两个方向的薄壁加劲板。这一新体系保留了混凝土薄壳屋盖的所有优点。又不需要使用临时模板.并大幅减少临时支撑。本文对这种新型结构体系及其各种可能的破坏模式进行了简单介绍,并给出了针对该结构体系施工阶段稳定性所进行模型试验的主要结果。 相似文献
5.
D. K. C. WU CChem MRSC H. C. LAI BSc MPhil CChem MRSC K. W. LAW BSc CChem MRSC W. C. WONG BSc CEng MIMechE MHKIE 《Water and Environment Journal》1995,9(1):82-91
In order to protect the sensitive waters in Tolo harbour (Hong Kong), Sha Tin and Tai Po sewage-treatment works were first designed to remove 70% of the nitrogen load from the sewage. Since then, due to continuing serious eutrophication problems in the harbour, both plants have been modified to increase the removal efficiency to 90%.
The modifications were based on the Bardenpho process. However, the designers of the two plants adopted different approaches to process intensity, complexity and control of bacterial foam. At Sha Tin, the average monthly results have shown an increase of total nitrogen removal from 60–70% to about 80% since its completion. The addition of methanol was found to be ineffective on further enhancement of the denitrification rate due to difficulties in the apportioning of the second anoxic zone. The overall monthly results for Tai Po have also shown an increase in the removal rate to about 80%, even though 90% was achieved for a short period of time. The major problem encountered at the latter plant was that the process design did not provide an effective control on bacterial foaming, which had affected the smooth operation of the process. 相似文献
The modifications were based on the Bardenpho process. However, the designers of the two plants adopted different approaches to process intensity, complexity and control of bacterial foam. At Sha Tin, the average monthly results have shown an increase of total nitrogen removal from 60–70% to about 80% since its completion. The addition of methanol was found to be ineffective on further enhancement of the denitrification rate due to difficulties in the apportioning of the second anoxic zone. The overall monthly results for Tai Po have also shown an increase in the removal rate to about 80%, even though 90% was achieved for a short period of time. The major problem encountered at the latter plant was that the process design did not provide an effective control on bacterial foaming, which had affected the smooth operation of the process. 相似文献
6.
A generalized transportation model is first formulated for the scheduling of Surface Mount Technology (SMT) production. Its dual form is next discussed. By specially coding the SMT scheduling problem, it is unnecessary to develop the constraint matrix for the dual. The simplex method is not applicable for this problem due to its sparse data structure. An efficient algorithm for the dual model is then developed from the idea of the revised simplex method. To illustrate the algorithm, a numeric example is presented. 相似文献
7.
用氧气代替空气中的部分或全部氮气可大大降低克劳斯硫回收及尾气处理装置的气体流量。对于新建装置,富氧技术可减小设备尺寸从而减少投资;对于改造项目,富氧技术是一个高投资效益的扩能方案。除经济优点外,富氧技术还可改善硫回收及尾气处理装置的操作,提高污染物分解率、硫回收率、操作可靠性和稳健性。富氧浓度可根据装置布局、处理能力、... 相似文献
8.
中国传统的"夷夏之辨"的思想一直影响着中国跟外族和外国的交往,其实也由此决定了译者的文化位置和社会身份.本文要处理的是19世纪中叶其中一位最早直接参与西籍翻译的中国知识分子王韬(1823-1897).作为传统文人,王韬为经济所迫受聘于上海的"洋夷",在极不情愿的情况下担负起宣扬西方文化的任务,承受着传统文化包袱的重压,被"华夷之辨"的思想困挠,无法认同自己的工作,无法确立自己的文化位置.从王韬的个案,我们可以看到在中西文化最初的碰撞中,传统文化思想同外来西方思想的矛盾和冲突,怎样透过其中的文化传播中介--译者,来体现出来.这一方面对于我们理解晚清中西文化交流的情况有所帮助,另一方面更可展示译者在当时独特的政治、文化环境下的复杂社会身份和文化位置. 相似文献
9.
讨论超短期风电功率预测(USTWPP)模型的适用性。提出的USTWPP方法,从历史数据的风电功率时间序列(WPTS)中筛选特征量,选择门限值,并将短窗口内的WPTS划分为不同形态的子集,以及一个囊括所有不具有排他性分类特征的"非形态子集"。然后在离线环境下,分别按对应的训练样本优化各子集专用的预测模型及参数。在线应用时,将当前时刻前一个短窗口的WPTS与各子集的分类判据比对,以归入上述子集之一,然后调用相应的预测模型完成USTWPP。最后,以实际算例验证了该方法的有效性。 相似文献
10.