Secondary cooling technology for high-efficiency continuous billet-casting

The mathematical model of high-efficiency continuous billet casting was developed, incorporating the effective spraying water coefficient and the effective specific spraying water flowrate of secondary cooling. To realize uniform cooling in secondary cooling zones, the spraying cooling structure and the arrangement of nozzles were redesigned and optimized, and an additional spraying cooling zone was used. A new secondary cooling model of spraying water was built. It was found that the required spraying water flowrate of a cooling zone was related with the casting speed, the casting temperature, the compositions of liquid steel and the cooling water temperature of secondary cooling. The operation of the reformed caster proved that the spraying cooling structure and the new secondary cooling model were suitable, and the casting speed was greatly enhanced. The highest casting speed was (3.8 to 4.0) m/min for billet with a section of 150×150 mm2. The quality and the output of the billet were improved, and the economical benefit was heightened.     

Lightweight design technology of planet carrier for wind turbine gearbox

A finite element model of one-arm planet carrier was built, and influence of structural parameters on strength and stiffness for one-arm planet carrier was analyzed. The stress and deformation of the round structure and the triangle structure for one-arm planet carrier were analyzed and compared. The finite element model of the same specifications arms planet carrier was established, and influence of the connecting slab thickness and input side plate thickness on strength and stiffness for arms planet carrier was analyzed. Strength, stiffness and mass for one-arm and arms planet carrier in the same specifications were analyzed and compared.     

Synthesis of Enriched 10B Boric Acid of Nuclear Grade

An economic and effective method of preparing enriched 10 B boric acid was established by chemical reaction of enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certain conditions. Calcium carbonate was selected to counteract hydrofluoric acid followed on. Some key operation factors were investigated, such as temperature, reaction time and the ratio of CaCO3 to 10BF3. The results showed that the yield of enriched 10 B boric acid could reach 97. 2% and the purity was up to 94. 1% under the following conditions: the temperature was 50—60,℃, the reaction time was 28 h and the ratio of CaCO3 to 10BF3 was 4. In addition, after recrystallization and titration analysis, the purity of the product could reach over 99. 2% from 94.1%.     

Development of quality function development matrix to measure the quality management performance of contractor

Quality function development (QFD) matrix was introduced as a tool to measure the quality management performance of contractors. Engineering quality, quality management system components, and their relationship were defined. An integrated engineering quality system was decomposed into seven factors and the quality management system was composed of eight factors. Importance weights of all factors and their relationship point were acquired by questionnaires and interviews. Then, QFD matrix was formulated and the calculating process was proposed. This model was verified on a case study. The result shows that it is useful for contractor in benchmarking themselves and invaluable for owners in the process of deciding contractor.     

Application of Dual Throttling Air-Conditioning System to Explosion-Proof Frequency Converter

An explosion-proof dual throttling air-conditioning system was put forward to solve the heat dissipation and internal dewing problems of explosion-proof frequency converter in the underground coal mine. This study investigated the feasibility and benefits of explosion-proof dual throttling cooling and dehumidification air-conditioning system applied to the explosion-proof frequency converter. The physical model of dual throttling air-conditioning system was established and its performance parameter was described by mathematical method. The design calculation of the system has also been done. The experimental result showed that the system reached the steady state at the refrigeration mode after running 45 min, and the maximum internal temperature of the flame-proof cavity was 31.0 ℃. The system reached the steady state at the dehumidification mode after running 37 min. The maximum internal relative humidity and temperature of the flame-proof cavity were 33.4% and 36.3 ℃, respectively. Therefore, the proposed system had excellent ability of heat dissipation and avoided internal dewing. Compared with water cooling system, it was more energy-saving and economical. The airflow field of dual throttling air-conditioning system was also studied by CFD simulation. It was found that the result of CFD numerical simulation was highly consistent with the experimental data.     

Application of automated image analysis to the identification and extraction of recyclable plastic bottles

An experimental machine vision apparatus was used to identify and extract recyclable plastic bottles out of a conveyor belt. Color images were taken with a commercially available Webcam, and the recognition was performed by our homemade software, based on the shape and dimensions of object images. The software was able to manage multiple bottles in a single image and was additionally extended to cases involving touching bottles. The identification was fulfilled by comparing the set of measured features with an existing database and meanwhile integrating various recognition techniques such as minimum distance in the feature space, self-organized maps, and neural networks. The recognition system was tested on a set of 50 different bottles and provided so far an accuracy of about 97% on bottle identification. The extraction of the bottles was performed by means of a pneumatic arm, which was activated according to the plastic type; polyethylene-terephthalate （PET） bottles were left on the conveyor belt, while non-PET bottles were extracted. The software was designed to provide the best compromise between reliability and speed for real-time applications in view of the commercialization of the system at existing recycling plants.     

Theoretical analysis and experimental study of an air inflated membrane structure

In this paper, an experimental study of an air inflated membrane was carried out based on the China National Stadium （the Bird＇s Nest）. After the 2008 Olympic Games, it was apparent that the future use of the Bird＇s Nest would be enhanced if rainfall could be prevented from entering the stadium. The installation of an air inflated membrane across the opening of the steel structure was proposed as a solution to this problem. To verify the scheme, a theoretical analysis and experimental study of an air inflated membrane was carried out. Experimental and computational models were developed, form-finding was carried out using both experimental and theoretical methods, and the results from the two approaches, including the deflection of the air inflated membrane and deformation of the support structure, were analyzed and compared. The force-transfer path and deformation of the air inflated membrane under loads was studied. Conclusions and suggestions are presented.     

Fuzzy Comprehensive Assessment Method to Determine Tectonic Stress Patterns

The tectonic stress patterns were determined by a fuzzy comprehensive assessment method. Data of in-situ survey and fault information were utilized in the method. First, by making pressure and tension in the directions of along-river, cross-river, shear clockwise, and shear counterclockwise , 26 types of tectonic stress patterns were presented. And the stress vector of each pattern was obtained with FE software by taking unit displacement as boundary load. Then, by taking the 26 types of tectonic stress patterns as index set and 3 main stresses as factor set and choosing various operators, comparison of directions of computational stress vector and survey stress vector was made and the most possible tectonic stress pattern was obtained. Taking the 26 types of tectonic stress patterns as index set and strike angle as factor set, comparison of relationships between formation of fault and tectonic stress was made,and the tectonic stress patterns were assessed with known fault information. By summarizing the above assessment results, the most impossible tectonic stress pattern was obtained . Finally an engineering case was quoted to validate that the method is more feasible and reliable than traditional empirical method.     

电磁驱动无阀并联微泵的设计与制作工艺

A parallel dynamic passive valveless micropump was designed, which consists of three layers-valve, diaphragm and electromagnetic coil. The valve was wetly etched in a silicon wafer, the diaphragm was a PDMS （polydimethyl siloxane） film spun on a silicon wafer with embedded permanent magnet posts, and the coil was electroplated on a silicon substrate. Under the actuation of the magnetic field generated by coils, the flexible diaphragm could be displaced upwards and downwards. After analyzing magnetic and mechanical characteristic of the flexible membrane and direction-dependence of the nozzle, a micropump was designed. And the relative length （L/d） of the micropump nozzle was taken 4. A 7 × 7 array of permanent magnetic posts was embedded in the PDMS film. Two diaphragms worked in an anti-step mode, which could relieve the liquid shock and increase the discharge of the micropump. The ANSYS and Matlab were adopted to analyze the actuation effect of the coil and the flow characteristic of the micropump. Results show that when actuated under a 0.3 A, 100 Hz current, the displacement of the diaphragm is more than 30 μm, and the discharge of the micropump is about 6 μL/s.     

Leak Detection in Water Distribution Systems Using Bayesian Theory and Fisher’s Law

A leak detection method based on Bayesian theory and Fisher’s law was developed for water distribution systems. A hydraulic model was associated with the parameters of leaks (location, extent). The randomness of parameter values was quantified by probability density function and updated by Bayesian theory. Values of the parameters were estimated based on Fisher’s law. The amount of leaks was estimated by back propagation neural network. Based on flow characteristics in water distribution systems, the location of leaks can be estimated. The effectiveness of the proposed method was illustrated by simulated leak data of node pressure head and flow rate of pipelines in a test pipe network, and the leaks were spotted accurately and renovated on time.     

EMDR在印度

2001年1月印度地震后,40名经过培训的EMDR治疗师援助了1600多人。儿童与成人均出现了PTSD的症状,但未发现人格解体症状。通过分析儿童的画可了解创伤对他们的影响,创伤越严重、丧失越多,个体的情绪就起伏越大,在那些较完整的较大的居民区,存在进一步被毁的威胁,在他们中间不安全感高于那些受破坏较大的地区。     

四川发生强烈地震——中国多处有震感

在此次强烈地震中遇难人数恐怕超过会5万,四川省受灾严重。5月12日下午2点28分发生的地震震级达到了里氏8．0级。震源位于四川省北部的汶川县,然而在千里之遥的北京和上海均有震感。     

浅论灾害心理危机及其救助

5.12汶川地震瞬间夺去了几万人的生命,几十万人受到了不同程度的身体伤害。震后重建工作展开至今,相较于肢体伤害,受灾群众的心灵伤害更为严重。事实上不仅仅是地震,其他严重的自然、人为灾害都会对受灾人的心理造成严重的困扰。对于我们这样的一个多灾多难的大国,开展灾害心理和灾害心理救助的研究具有极其深刻的社会和现实意义。     

再论唐山抗震精神及其传承价值

在1976年唐山大地震中,唐山人民用鲜血与生命凝成的"公而忘私,患难与共,百折不挠,勇往直前"的抗震精神,是传统民族精神的升华与时代文化的积淀。它有长久的传承价值,是助推道德建设的动力,是建设社会主义核心价值体系的丰厚精神资源;是激励人民奋发上进,推动建设中国特色社会主义事业和防灾减灾的力量源泉;是教育青少年树立健康向上生活态度的鲜活教材。     

从心灵之痛到亲情之暖——比较小说《余震》与电影《唐山大地震》内容表现之异同

同为表现唐山大地震在震后给人们带来的影响,电影《唐山大地震》与小说《余震》在内容表现上有很大的不同。电影《唐山大地震》表现了人在灾难面前的脆弱,同时也关注了灾后人们如何释怀并摆脱心灵的枷锁。而《余震》不仅仅表现出大地震给唐山造成的破坏,更着力表现那场浩劫在经历者内心深处造成的强烈余震。在电影里,疼痛被温暖取代。     

童亭煤矿地下水位异常与汶川地震

汶川地震是建国以来我国发生的震级最大的地震之一,造成了巨大的人员伤亡和财产损失。在汶川地震发生前后的一段时间内,童亭矿新生界松散层第四含水层水位发生了极大的异常变化,对地震预报有一定的借鉴意义。     

汶川抗震救灾之中国人文精神的评述

从以人为本的精神、民族精神、艰苦奋斗精神、社会主义互助精神等方面对汶川抗震救灾之中国人文精神进行评述。     

弘扬时代精神 加强大学生价值观引导

我国人民在党中央的坚强领导下,战胜了世所罕见的四川汶川强烈地震,培育了伟大的抗震救灾精神。这种精神是全党和人民的宝贵财富,也是新形势下高等院校开展思想教育的极好内容,对于引导广大青年学生树立正确的价值观具有重要意义。     

四川汶川地震与举国抗震救灾

本刊编辑部在参阅主要媒体关于四川汶川地震信息资料基础上,将四川汶川地震灾情和全国人民支援抗震救灾实践轭要,摘编成文,并配合之简要介绍了1949年后中国特大地震概况及汶川地震留给地学界最有探索性的命题——地震可测性与地震不可测性。     

Disaster,civil society and education in China: A case study of an independent non-government organization working in the aftermath of the Wenchuan earthquake

In May 2008 nearly 90,000 people died in the most powerful earthquake in modern Chinese history. Many were students killed in substandard schools, creating a sensitive disaster zone inside a nation whose civil society organizations are beginning to flourish. This paper examines the education earthquake relief program of an international NGO, and the institutional environment the organization worked in. We argue that the restricted environment prevented implementation of high-impact programs in the most deprived places, but that the NGO needed to use the institutional opening created by the earthquake to establish a presence as an agent in China's development.