An Improved Algorithm for Identifying Objects in Code

The identification of abstractions within existing software systems is an important problem to be solved to facilitate program comprehension and the construction of a set of reusable artifacts. In particular, of interest is the identification of object-like features in procedural programs. Existing techniques and algorithms achieve some level of success but do not, in general, always precisely identify a coherent set of objects. The identified objects tend to contain spurious methods that are only tenuously related to the object and require a great deal of human effort and understanding to unravel. This paper presents an improved algorithm that overcomes these drawbacks and enables the precise identification of objects with less human intervention and understanding by exploiting simple statistical techniques. The algorithm is applied to several sample programs and the results are compared with existing algorithms. Finally, the application of the algorithm to a real medium-size system is described and discussed. The algorithm was developed as part of the RE² project in which the identification of object-like features in existing systems is the basis for a re-engineering process aimed at populating a repository of reusable assets.     

Evaluation of the exploitation of nontraditional water resources—— Case study of Yantian District in Shenzhen

Yantian District in Shenzhen is a water deficient area. Water shortage has become a major obstacle to its further economic progress. Consequently, rational exploitation of nontraditional water resources(NWR)has been naturally adopted to increase local available water volume. The purpose of this paper is to analyse the exploitation of two kinds of NWR, namely wastewater reuse and seawater utilization, in Yantian District, and assess the contribution of each mode to deal with the water crisis. Two different nontraditional water supply systems respectively based on the reclaimed water and sea water were presented, and the effects of each system were evaluated in terms of technology, economy and environment. The result shows that both wastewater reclamation and reuse (WRR) and direct utilization of seawater (DUS) are of great importance to cope with the tight water resource situation in the district. The data indicate that the fresh water saved by WRR system and DUS system is 29 and 17 million m3/a respectively. Moreover, the BOD, COD, NH3-N and T-P reduced by the WRR system are 870, 2900, 725 and 87 t/a, respectively. Considering the integrated effectiveness, the development of WRR system, which is of specific significance to exploiting new water resource and save natural fresh water supplied from distant water diversion project, is the preferred methods used to solve the water shortage problem in Yantian District and recover the water environment as well as maintain the sustainable development of the city zone.     

氟石膏的改性及其综合利用

氟石膏是氢氟酸生产过程中的副产品,主要用于水泥和建筑材料行业。采用外加添加剂,辅以适宜的工艺条件对氟石膏进行改性改善其胶凝性能、增强其机械强度,拓宽氟石膏综合利用的新途径,已成为近年来研究的热点。对氟石膏的化学组成与相态变体、水化硬化机理与表面改性作用进行了讨论,对氟石膏的主要改性措施与改性材料、生产工艺和主要应用领域进行了综述,并就改性氟石膏综合应用中存在的关键问题进行了展望。     

实现城市污水资源化的基本途径初探

通过对解决城市缺水方案的比较得出：污水资源化是最佳选择。实施污水资源化，按照以下指导原则进行：优水优先，一水多用，重复利用，保证人体健康不受威胁，先近后远，先易后难；处理后的城市污水在满足水质要求的条件下，用于农业灌溉、工业用水、补充城市湖泊、河道、市政园林、绿地浇灌用水；经二级处理后满足生活杂用；因季节性差异利用现有坑塘储存再生水，作为水源之一；利用城市污水回灌地下水等。     

浅析Observer模式在GIS软件设计中的应用

面向对象方法仅仅从问题域的离散抽象很难达到高内聚和低耦合,设计模式的出现和广泛应用为解决这个问题提供了有效的方法.探讨了Observer模式的基本原理以及在GIS软件设计中的应用,并在具体实践中做了有益尝试.实践证明了设计模式在改善软件的灵活性和适应性方面所发挥的积极作用.     

Validating behavioral models for reuse

When using a model to predict the behavior of a physical system of interest, engineers must be confident that, under the conditions of interest, the model is an adequate representation of the system. The process of building this confidence is called model validation. It requires that engineers have knowledge about the system and conditions of interest, properties of the model and their own tolerance for uncertainty in the predictions. To reduce time and costs, engineers often reuse preexisting models that other engineers have developed. However, if the user lacks critical parts of this knowledge, model validation can be as time consuming and costly as developing a similar model from scratch. In this article, we describe a general process for performing model validation for reused behavioral models that overcomes this problem by relying on the formalization and exchange of knowledge. We identify the critical elements of this knowledge, discuss how to represent it and demonstrate the overall process on a simple engineering example.

Regeneration of AgXO@SBA-15 for reactive adsorptive desulfurization of fuel

Adsorbent regeneration is critical for a continuous adsorption–regeneration process and often underestimated. In this work,the regeneration of bifunctional AgXO@SBA-15 for [O]-induced reactive adsorptive desulfurization of liquid fuel is reported and further investigated. The spent AgXO@SBA-15 was regenerated in various types of solvents followed by calcination and tested in multiple desulfurization–regeneration cycles. The effects of regenerate solvents were also compared systematically. The original and regenerated AgXO@SBA-15 was characterized by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, N_2 adsorption, X-ray photoelectron spectroscopy and atomic absorption spectrometry. The recovery of desulfurization capacity using various solvents follows the order of acetonitrile [ acetone [ ethanol [ methanol [ water. Owing to the complete reduction of silver species to Ag~0 and severe agglomeration of Ag~0, the bifunctional AgXO@SBA-15 demonstrating [ 85%(2.60 mg-S/g) of sulfur removal dramatically reduced to \ 46%(1.56 mg-S/g) after only 1 st-cycle regeneration. It is suggested that polar organic species strongly adsorbed(or residual) on the spent AgXO@SBA-15, in that case, after solvent wash may contribute to the accelerated decomposition of Ag~+ to Ag~0 in the following calcination step. The desulfurization capacity decreased rather mildly in the later regeneration runs. Cautious choice of regeneration conditions and strategies to rational design stabilized adsorbents is required to avert the adsorbent deactivation.     

Composite with Recyclable Loads for the Manufacture of Blocks to Build Popular Houses

The science space in a state school in Natal city was built using a composite consisting of gypsum, EPS （expanded polystyrene）, shredded tire, cement and water. Mechanical and thermal resistances were evaluated. Inside the blocks, three types of fillings （EPS plates, aluminum cans and 500 mL bottles of mineral water） were placed in order to obtain a walls with higher thermal resistance, but also to give it an ecologically correct order, considering that both the tire and the EPS occupy a large space in landfills and require years to be degraded when released into the environment. Compression tests were conducted according to the rules. The experiments demonstrated that the temperature difference between the internal and external surfaces on the walls reached levels above 12.0 ℃. It was also demonstrated that the proposed composite has adequate mechanical strength to be used for sealing walls. The proposed use of the composite can contribute to reduce the significant housing deficit of Brazil, producing popular houses at low cost and with little time to work.     

Effect of bed height on the carbon dioxide capture by carbonation/regeneration cyclic operations using dry potassium-based sorbents

The effect of bed height on CO₂ capture was investigated by carbonation/regeneration cyclic operations using a bubbling fluidized bed reactor. We used a potassium-based solid sorbent, SorbKX35T5 which was manufactured by the Korea Electric Power Research Institute. The sorbent consists of 35% K₂CO₃ for absorption and 65% supporters for mechanical strength. We used a fluidized bed reactor with an inner diameter of 0.05 m and a height of 0.8 m which was made of quartz and placed inside of a furnace. The operating temperatures were fixed at 70 °C and 150 °C for carbonation and regeneration, respectively. The carbonation/regeneration cyclic operations were performed three times at four different L/D (length vs diameter) ratios such as one, two, three, and four. The amount of CO₂ captured was the most when L/D ratio was one, while the period of maintaining 100% CO₂ removal was the longest as 6 minutes when L/D ratio was three. At each cycle, CO₂ sorption capacity (g CO₂/g sorbent) was decreased as L/D ratio was increased. The results obtained in this study can be applied to design and operate a large scale CO₂ capture process composed of two fluidized bed reactors. This work was presented at the 7 ^th China-Korea Workshop on Clean Energy Technology held at Taiyuan, Shanxi, China, June 26–28, 2008.     

环己醇装置水合催化剂流失原因的分析

分析了环己烯水合催化剂流失的原因,结果表明：搅拌器转速、催化剂浓度、催化剂界面是影响催化剂流失的主要原因,催化剂的再生、劣化也是影响催化剂流失的原因;工艺优化条件：反应温度120℃,压力0．5MPa、搅拌器转速45r／min、催化剂质量分数20％、催化剂界面10％。工艺优化改进后效果显著。