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Clean Technologies and Environmental Policy - Industrial wastes can be used as alternative fuel sources for the substitution of fossil fuel if they contain good calorific values. Through... 相似文献
104.
Guo Liang Goh Jiaheng Ma Kwee Lim Francis Chua Agarwala Shweta Yue Ping Zhang 《Virtual and Physical Prototyping》2016,11(4):289-294
This research focuses on exploring low-cost and rapid production solutions for fabricating emitters for patch antennas for wireless communication applications. Additive manufacturing technique is employed to fabricate two patch antennas using silver nanoparticle ink on FR4 substrate. Finite-element simulation software, HFSS is used to analyse and predict the theoretical performance of the antenna designs for 2.4?GHz MIMO and 6?GHz wireless data transmission. The fabricated antennas have resonant frequencies closely matching the design values. The work provides a viable solution for fabricating emitters and finally antennas commercially using inkjet printing platform, thus overall reducing the cost and simplifying the process. 相似文献
105.
Helen Hejin Park Rachel Heasley Leizhi Sun Vera Steinmann Rafael Jaramillo Katy Hartman Rupak Chakraborty Prasert Sinsermsuksakul Danny Chua Tonio Buonassisi Roy G. Gordon 《Progress in Photovoltaics: Research and Applications》2015,23(7):901-908
Thin‐film solar cells consisting of earth‐abundant and non‐toxic materials were made from pulsed chemical vapor deposition (pulsed‐CVD) of SnS as the p‐type absorber layer and atomic layer deposition (ALD) of Zn(O,S) as the n‐type buffer layer. The effects of deposition temperature and annealing conditions of the SnS absorber layer were studied for solar cells with a structure of Mo/SnS/Zn(O,S)/ZnO/ITO. Solar cells were further optimized by varying the stoichiometry of Zn(O,S) and the annealing conditions of SnS. Post‐deposition annealing in pure hydrogen sulfide improved crystallinity and increased the carrier mobility by one order of magnitude, and a power conversion efficiency up to 2.9% was achieved. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
106.
串联活性污泥系统处理制药废水工艺研究 总被引:1,自引:0,他引:1
通过小试模拟完全混合推流式活性污泥曝气池(串联CMAS工艺)处理哈尔滨某制药生产废水,优化实际工程的工艺运行参数,研究各污染物在系统中的去除特性.在F/M为0.1~0.2或0.8~1.5 gCOD/(gMLSS.d)、SRT为8~10 d、DO为1~3 mg/L、水温为27~34℃的运行条件下,串联CMAS工艺系统中污泥沉降性较好,对COD和TSS去除率分别大于90%和95%.活性污泥的平均比摄氧速率SOUR平均=49.5 mg/(gMLSS.h),表明串联CMAS曝气池中的污泥具有良好的活性.当水力停留时间HRT相同时,增加CMAS曝气池数有利于污泥沉降.该工艺对COD的生物降解规律遵循ρ(CODe)=ρ(COD0)×e-a t的数学模型.将模拟试验结论应用于实际工程的运行结果表明,该系统运行高效稳定,出水指标满足《污水综合排放标准(GB8978-1996)》的一级标准. 相似文献
107.
Ping Seng Chua 《Polymer Composites》1987,8(5):308-313
The dynamic mechanical properties of unidirectional glass-fiber-reinforced polyester measured along the fiber direction were recently investigated. In the same polyester, the type of organosilane coated on the glass fiber, the amount of organosilane, the fiber volume fraction, and the fiber diameter affect the value of the loss tangent, tan δ, at the glass-transition temperature of the glass-fiber-reinforced polyester. The interfacial shear strength and the tan δ at the glass-transition temperature of the glass-fiber-reinforced polyester show good correlation suggesting that the latter can be used to characterize the quality of the interphase. Factors affecting the glass-transition temperature and the application of Zorowski and Murayama's equation in the characterization of the interfacial adhesion are also discussed. 相似文献
108.
Chua Elizabeth F.; Schacter Daniel L.; Sperling Reisa A. 《Canadian Metallurgical Quarterly》2009,24(1):139
Although several studies have examined the neural basis for age-related changes in objective memory performance, less is known about how the process of memory monitoring changes with aging. The authors used functional magnetic resonance imaging to examine retrospective confidence in memory performance in aging. During low confidence, both younger and older adults showed behavioral evidence that they were guessing during recognition and that they were aware they were guessing when making confidence judgments. Similarly, both younger and older adults showed increased neural activity during low- compared to high-confidence responses in the lateral prefrontal cortex, anterior cingulate cortex, and left intraparietal sulcus. In contrast, older adults showed more high-confidence errors than younger adults. Younger adults showed greater activity for high compared to low confidence in medial temporal lobe structures, but older adults did not show this pattern. Taken together, these findings may suggest that impairments in the confidence–accuracy relationship for memory in older adults, which are often driven by high-confidence errors, may be primarily related to altered neural signals associated with greater activity for high-confidence responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Di Ventra M. Pershin Y.V. Chua L.O. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2009,97(10):1717-1724
We extend the notion of memristive systems to capacitive and inductive elements, namely, capacitors and inductors whose properties depend on the state and history of the system. All these elements typically show pinched hysteretic loops in the two constitutive variables that define them: current-voltage for the memristor, charge-voltage for the memcapacitor, and current-flux for the meminductor. We argue that these devices are common at the nanoscale, where the dynamical properties of electrons and ions are likely to depend on the history of the system, at least within certain time scales. These elements and their combination in circuits open up new functionalities in electronics and are likely to find applications in neuromorphic devices to simulate learning, adaptive, and spontaneous behavior. 相似文献
110.
This paper proposes a case-based reasoning (CBR) approach to construction hazard identification that facilitates systematic feedback of past knowledge in the form of incident cases and hazard identification. This paper focuses on two of the key components of the CBR approach: (1) a detailed knowledge representation scheme, developed based on the modified loss causation model, to codify incident cases and past hazard identification and (2) an intelligent retrieval mechanism that can automatically retrieve relevant past cases. The detailed knowledge representation scheme presented herein is designed to model both incident cases and hazard identification so that both types of knowledge repository can be retrieved simultaneously and adapted for use. The scheme also includes a linguistic structure used to facilitate indexing of cases. The retrieval mechanism is based on the concept of similarity scoring. In this paper, a novel scoring technique based on semantic networks is presented. A case study is presented to demonstrate and validate the proposed approach. 相似文献