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41.
This study is to evaluate the potential for development of a cellulosic ethanol facility in Vietnam. Rice straw is abundant in Vietnam and highly concentrated in the Mekong Delta, where about 26 Mt year−1 of rice straw has been yearly produced. To minimize the overall production cost (PC) of ethanol from rice straw, it is crucial to choose the optimal facility size. The delivered cost of rice straw varied from 20.5 to 65.4 $ dry t−1 depending on transportation distance. The Mekong Delta has much lower rice straw prices compared with other regions in Vietnam because of high density and quantity of rice straw supply. Thus, this region has been considered as the most suitable location for deploying ethanol production in Vietnam. The optimal plant size of ethanol production in the region was estimated up to 200 ML year−1. The improvement in solid concentration of material in the hydrothermal pre-treatment step and using residues for power generation could substantially reduce the PC in Vietnam, where energy costs account for the second largest contribution to the PC, following only enzyme costs. The potential for building larger ethanol plants with low rice straw costs can reduce ethanol production costs in Vietnam. The current estimated production cost for an optimal plant size of 200 ML year−1 was 1.19 $ L−1. For the future scenario, considering improvements in pre-treatment, enzyme hydrolysis steps, specific enzyme activity, and applying residues for energy generation, the ethanol production cost could reduce to 0.45 $ L−1 for a plant size of 200 ML year−1 in Vietnam. These data indicated that the cost-competitiveness of ethanol production could be realized in Vietnam with future improvements in production technologies.  相似文献   
42.
Expanded gamut printing is an approach in color reproduction that expands the color gamut of conventional CMYK printing processes via the use of additional colorants, such as Orange, Green, and Violet inks. This study evaluates the ability of commercial color management software to create an accurate solution for an expanded gamut printing system. In this study, two printing processes were used, an Epson SureColor P9000 inkjet printer/proofer and an HP Indigo 7900 digital production press, both with 7-color expanded gamut ink sets. Software solutions from Alwan, CGS ORIS, ColorLogic, GMG Color, Heidelberg, and Kodak were evaluated. The systems were tested to see how well they could reproduce the colors in the entire PANTONE+ Solid Coated spot color library. It is shown that the solutions are able to reproduce 89% to 94% of the spot colors on the Epson P9000 inkjet printer and 77% to 87% of the library on the Indigo 7900, both to less than two CIEDE2000 (a typical tolerance in label and packaging work). The number of color patches in expanded gamut characterization test charts was noted, as this is still an area of proprietary, nonstandardized working practice. There are many different colorant combinations that can make the same color in expanded gamut printing. The ink build created by the different software solutions was studied, as it relates to press stability through appropriate choice of colorants. Pantone and Adobe provide everyday commercial tools for expanded color workflows. The study identified some issues with products from these companies that could confuse a less-skilled user in a busy production environment. The conclusion of the study is that expanded gamut solutions for spot color printing produce totally acceptable results for digital printing processes; expanded gamut printing is ready, here and now. The findings show that expanded gamut printing can replace cumbersome conventional spot color workflows creating considerable savings and advantages, especially for label and packaging printers.  相似文献   
43.
26 interviews were conducted with a snowball sample of project managers to explore how project managers were influenced by accountability arrangements and how they responded to accountability demands. Using a grounded theory approach to code the interview data, this study revealed that project managers develop new skills to respond to accountability demands. These effects are facilitated by the interaction of resource-based mechanisms and reflexivity that interact with the contextual factors of the project. The study broadens the understanding of accountability in project management and suggests a model for further empirical examination.  相似文献   
44.
杨凡 《住宅产业》2020,(3):64-65
随着BIM技术的进步,建筑行业越来越重视BIM技术的应用,并在应用过程中取得一定的成效。本文从工程造价决策、设计、招投标、施工、竣工五个阶段阐述BIM技术在建筑工程造价中的应用对策。  相似文献   
45.
李兆生 《山东煤炭科技》2015,(1):112-113,118
对2320隐蔽老火区首先通过灌注泥浆对火区进行治理,同时对部分裂隙通道进行堵漏,然后对泥浆不能到达的区域注入高倍数三相泡沫灭火材料泡沫,瞬间将火源处覆盖,火源因隔绝氧气而窒息灭火。三相泡沫具有良好的堆积性和流动性,对煤体具有保水保湿,惰化遗煤氧化空间,并能够对松散煤体进行化学阻化,从本质上降低遗煤自然氧化速率,消灭了隐蔽老火区的火灾隐患,具有较高的推广价值。  相似文献   
46.
The objective of this paper is to review and document the mine fleet management systems’ models and algorithms. The purpose is to understand the algorithms behind the fleet management systems and the proposed academic solutions in this area to identify any gaps in the current literature and to open up opportunities to establish research questions that need to be addressed in an integrated simulation and optimisation operational planning research framework. In this paper, we review industrial fleet management systems and the main academic algorithms behind such systems. The fleet management systems are divided into three subsequently related problems to review: shortest path, production optimisation and real-time dispatching. Finally, the limitations of current algorithms for fleet management systems are documented in terms of mining practice feasibility and optimality of the solution on large-scale problems. The results of this literature review enable us to evaluate the logical links between major components of an integrated simulation and optimisation operational planning framework with current theory of fleet management systems.  相似文献   
47.
The present work is an attempt to investigate the adoption of sustainable supply chain management (SSCM) practices amongst manufacturing and process based organisations in India and its impact on organisational performance encompassing all three dimensions of sustainability. SSCM practices conceived in the present study include environmental management practices (EMP), socially inclusive practices for employees (SPE), socially inclusive practices for community (SPC), operations practices (OP) and supply chain integration (SCI) which were treated as exogenous variables. Organisational performance considered in this study includes five dimensions, namely environmental performance (EPR), employee-centred social performance (ESP), community-centred social performance (CSP), operations performance (OPR) and competitiveness, which were regarded as endogenous variables. The analysis was carried out with the help of structural equation modelling considering natural logarithm of manpower as a control variable. Few major findings are mentioned. EMP does not have any significant association with OPR, nor does it result in competitiveness. However, when jointly mediated through both EPR and OPR, EMP leads to competitiveness. SPC has significant negative association with competitiveness, when only direct relationship is considered. However, indirect relationship between SPC and competitiveness shows significant positive association when mediated through CSP. The resultant total effect between SPC and competitiveness turns out to be insignificant. Further, OPR fully mediates the relationship between OP and competitiveness. Managerial implications of the findings are discussed.  相似文献   
48.
葛洲坝水利枢纽泄水建筑物进水口冲磨与修复   总被引:2,自引:1,他引:1  
葛洲坝水利枢纽工程已运行20余年,近年水下检查中发现泄水建筑物进水口存在不同程度的冲磨,有些已威胁到建筑物安全运行,分析冲磨原因和探讨修复材料和手段是非常重要的,本文就此问题提出一些看法和建议供参考。  相似文献   
49.
由于AD HOC网络自身的特点,其网络管理很多方面与固定网络不同,如移动性管理和体系结构管理等。讨论了AD HOC网络管理的各个方面,并列举了各个方面的设计思路和已有的相关算法的简介。  相似文献   
50.
径向基函数网络(RBFN)已广泛应用于参考腾发量预测等领域,但常用的K均值聚类和自组织特征映射等方法在求取径向基函数网络隐层节点中心时存在较大不足。针对这一问题,本文引入投影寻踪方法,在投影降维的基础上实现对大量高维数据的聚类,建立了基于投影寻踪的径向基函数网络模型,并将该模型应用于山西潇河灌区参考腾发量的预测,研究了不同气象因子输入对参考腾发量预测精度的影响。结果表明,基于投影寻踪的径向基函数网络具有较强的适用性,只需使用最高温度、最低温度、日照时数和旬序数作为输入因子,就能以较高的精度预测参考腾发量。  相似文献   
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