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971.
Since 2009, the Mine Safety and Health Administration(MSHA) has required mines to install refuge alternatives(RAs) in underground coal mines. One of the biggest concerns with occupied RAs is the possible severity of the resulting thermal environment. In 30 CFR 7.504, the maximum allowable apparent temperature(AT) for an occupied RA is specified as 35 °C(95 °F). Manufacturers must conduct heat/humidity tests to demonstrate that their RAs meet the 35 °C(95 °F) AT limit. For these tests, heat input devices are used to input the metabolic heat of actual miners. A wide variety of test methods, sensors, and heat input devices could be used when conducting such tests. Since 2012, the National Institute for Occupational Safety and Health(NIOSH) has conducted over thirty 96-hour heat/humidity tests on four different RAs. This paper discusses the test equipment and procedures used during these investigations. This information is useful for RA manufacturers conducting RA heat/humidity tests, for other researchers investigating RA heat/humidity buildup, and for those who need to assess the thermal environment of any confined space where people may be trapped or are seeking refuge.  相似文献   
972.
文章从风景园林学科的角度出发,对传统老广州曾经存在的地域人文景观里的典型——滨水动态人文景观进行了初步的全面整理,以日常型滨水动态人文景观和节庆型滨水动态人文景观为两种基本类型,总结梳理出超过25种滨水动态人文景观的主要类型,充分说明了广州市传统滨水动态人文景观的多样性和独特性。并以景观格局的理论视角分析了传统滨水动态人文景观在广州旧城的空间格局,分析得出其两个核心聚集区:以祭祀水神的仁威神庙为精神核心节点的呈圆形扩散的西关功能核心区和以长堤滨江段为中线的呈椭圆形扩散的珠江两岸功能核心区,并总结了促使这种人文景观发展与繁盛的历史经验,为广州地域文化景观的发扬及旧城更新工作提供借鉴。  相似文献   
973.
Acute lymphoblastic leukaemia (ALL) is a relevant form of childhood neoplasm, as it accounts for over 80% of all leukaemia cases. T-cell ALL constitutes a genetically heterogeneous cancer derived from T-lymphoid progenitors. The diagnosis of T-ALL is based on morphologic, immunophenotypic, cytogenetic, and molecular features, thus the results are used for patient stratification. Due to the expression of surface and intracellular antigens, several subtypes of T-ALL can be distinguished. Although the aetiology of T-ALL remains unclear, a wide spectrum of rearrangements and mutations affecting crucial signalling pathways has been described so far. Due to intensive chemotherapy regimens and supportive care, overall cure rates of more than 80% in paediatric T-ALL patients have been accomplished. However, improved knowledge of the mechanisms of relapse, drug resistance, and determination of risk factors are crucial for patients in the high-risk group. Even though some residual disease studies have allowed the optimization of therapy, the identification of novel diagnostic and prognostic markers is required to individualize therapy. The following review summarizes our current knowledge about genetic abnormalities in paediatric patients with T-ALL. As molecular biology techniques provide insights into the biology of cancer, our study focuses on new potential therapeutic targets and predictive factors which may improve the outcome of young patients with T-ALL.  相似文献   
974.
衡冲  沈华  王府梅 《纺织学报》2020,41(12):42-48
针对光电法测试纤维长度等性质时,存在纤维的透光及反光信号与颜色高度相关的问题,采用数字化方法表征羊绒的颜色类别并精准地测量羊绒的长度。将彩色光电耦合器作为测色传感器,搭建了更适合纤维材料的测色装置;通过颜色模型在3种色空间的转换,得到3类颜色的羊绒在三维色空间的分布;基于系列实验,创建了有色羊绒的光学参数即无穷厚时的表观反射率表观反射率与测色装置计算的亮度指标之间的换算模型,并用实验证明采用测得的表观反射率可计算得到准确的须丛线密度曲线,从而可用光电法精准测量有色羊绒的长度。结果表明,该测色方法的测样面积大,代表性好,成本低,同时可用于其他纤维和纺织品的颜色测量。  相似文献   
975.
This article presents a design, modeling, simulation, and measurements of a hybrid photocurrent-to-digital converter integrated together with photo-diodes in a 130 nm CMOS process, without any additional process steps. Photo-currents of integrated photo-diodes with different responsivities to different wavelength of the light and light intensity are converted into 22-bits digital results in 2 ms. The results can then be converted into CIE XYZ or RGB color luminosity space using dedicated DSP algorithm. A high resolution, hybrid, ADC converts light induced photo-currents into 22-bit digital results, canceling the dark current of the photodiodes and 1/f noise and offset voltage of the input stage of the modulator. The whole converter consumes on average less than current at supply voltage at 10 conversions per second. It occupies approx. 0.8 mm2 of silicon area, including the three photodiodes, a multiplexer, and the ΣΔ modulator.  相似文献   
976.
Cinema as an influential mass medium continuously represents different spaces, environments, events, and symbols, and through which it reproduces viewers’ social reminiscence and merges imagination and reality in a constant manner. This paper attempts to illuminate the outlook of Iranian cinema on urban spaces (In this paper, urban space means “outdoor space” or “open space.” However, our purpose of applying the term “urban space” is an emphasis on the word “urban.” This includes what is connected with a city and its spaces and buildings, residents, and even social, economic, and political issues.), and to analyze the quality of their representation during the last two decades (1979–2006). Identifying displayed urban spaces and determining their strength and limitations, this endeavor not only offers guidelines on urban design pedagogy but also examines impacts of cinema on audiences’ visual literacy and perception, thereby exploring their expectations of urban environment.Based on content analysis of selected movies, we find that the Iranian films only occasionally involve urban spaces, and if they do, this practice is confined to historical or cultural spaces. This failure could be attributed to the poverty of urban spaces and limitations facing the film industry in such spaces on the one hand, and lack of the directors’ appropriate understanding of contemporary urban spaces and their mere attention to nostalgic spaces on the other hand.  相似文献   
977.
To improve the performance of the standard particle swarm optimization (PSO) which suffers from premature convergence and slow convergence speed, many PSO variants introduce lots of stochastic or aimless strategies to overcome the convergence problem. However, the mutual learning between elites particles is omitted, although which might be benefit to the convergence speed and, prevent the premature convergence. In this paper, we introduce DSLPSO, which integrates three novel strategies, specifically, tabu detecting, shrinking and local learning strategies, into PSO to overcome the aforementioned shortcomings. In DSLPSO, search space of each dimension is divided into many equal subregions. Then the tabu detecting strategy, which has good ergodicity for search space, helps the global historical best particle to detect a more suitable subregion, and thus help it jump out of a local optimum. The shrinking strategy enables DSLPSO to take optimization in a smaller search space and obtain a higher convergence speed. In the local learning strategy, a differential between two elites particles is used to increase solution accuracy. The experimental results show that DSLPSO has a superior performance in comparison with several other participant PSOs on most of the tested functions, as well as offering faster convergence speed, higher solution accuracy and stronger reliability.  相似文献   
978.
The objectives of this study were to develop a predictive statistical model for low-fill-weight capsule filling of inhalation products with dosator nozzles via the quality by design (QbD) approach and based on that to create refined models that include quadratic terms for significant parameters. Various controllable process parameters and uncontrolled material attributes of 12 powders were initially screened using a linear model with partial least square (PLS) regression to determine their effect on the critical quality attributes (CQA; fill weight and weight variability). After identifying critical material attributes (CMAs) and critical process parameters (CPPs) that influenced the CQA, model refinement was performed to study if interactions or quadratic terms influence the model. Based on the assessment of the effects of the CPPs and CMAs on fill weight and weight variability for low-fill-weight inhalation products, we developed an excellent linear predictive model for fill weight (R2?=?0.96, Q2?=?0.96 for powders with good flow properties and R2?=?0.94, Q2?=?0.93 for cohesive powders) and a model that provides a good approximation of the fill weight variability for each powder group. We validated the model, established a design space for the performance of different types of inhalation grade lactose on low-fill weight capsule filling and successfully used the CMAs and CPPs to predict fill weight of powders that were not included in the development set.  相似文献   
979.
伍静 《城市建筑》2014,(29):204-204
本文通过文献查阅与现场调研,梳理了武侯祠的景观特点,分析其特殊的营造方式、地域文化与景观元素的转化和景观元素的合理化表达,总结前人积累下来的经验和智慧,希望能对今后在景观设计中对城市地域文化特色的表达有一定的借鉴作用。  相似文献   
980.
《工程(英文)》2018,4(1):103-111
Given the increasingly notable segmentation of underground space by existing subway tunnels, it is difficult to effectively and adequately develop and utilize underground space in busy parts of a city. This study presents a combined construction technology that has been developed for use in underground spaces; it includes a deformation buffer layer, a special grouting technique, jump excavation by compartment, back-pressure portal frame technology, a reinforcement technique, and the technology of a steel portioning drum or plate. These technologies have been successfully used in practical engineering. The combined construction technology presented in this paper provides a new method of solving key technical problems in underground spaces in effectively used cross-subway tunnels. As this technology has achieved significant economic and social benefits, it has valuable future applications.  相似文献   
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