通风量对粉管冷态风量调平的影响

通过理论分析及实例计算研究通风量对粉管冷态风量调平的影响。由理论分析可知:纯空气下,粉管气流流动阻力与流速的平方成正比;各个粉管风量分配比例与粉管阻力相关,与通风量无关;通风量对粉管风量调平结果无影响;大的通风量有利于粉管风量的准确测量。对粉管冷态风量调平试验数据进行分析,验证了不同的通风量工况下,各个粉管的气流流动相似,各个粉管的风量偏差相似。

压缩比法与风量调节法测定柴油十六烷值的对比

从试验原理、方法准确度和精密度等方面将压缩比法与风量调节法测定柴油十六烷值的两种试验方法进行比较,样品检测试验结果表明,两种分析方法的测定结果均可靠。与压缩比法相比,风量调节法具有分析速度快和测定精度高等优点。

风机风量交流调压调节系统试验研究

本文从分析风机调速节能原理出发,论述了用双向晶闸管、集成触发器和PI调节器,组成风机风量交流调压调速调节系统的设计方案和试验结果,并对调节系统特性作分析评价.

关于定风向可调风量回风口

结合定风向可调风量回风口课题的研制,介绍了该产品的研制过程。

基于大人流量、大空间空调系统设计及运行不合理现象的思考

针对如今大卖场、大商场之类空间大、人流量大的场所空调系统的设计和运行中普遍存在的不合理现象,提出自己的见解。对照相关设计规范和节能设计标准,指出这些工程的空调系统设计不符合相关的规定要求。明确提出一个观点,即大空间、大人流场所的空调,应该采用全空气式空调系统,而且其室内温度设定值和新风量应该做到全年自动可调,以满足这类场所全年舒适、卫生、节能、经济运行的要求。

#1炉冷态空气动力场试验

#1炉停炉检查时发现部分燃烧器喷口烧损、磨损变形,喷口积灰严重,部分燃烧器固定螺栓脱落,导致燃烧器假想切圆混乱。除#4磨煤机外,其余3台磨煤机四角一次风速偏差较大。在2015年6月在#1炉上进行了冷态空气动力场试验对燃烧器假想切圆进行了重新调整。调整后燃烧器假想切圆中心基本处于炉膛中央,各层一次风刚性均较强,气流不偏斜。

嘉兴电厂1025t/h锅炉试运期间结渣原因分析及对策

本文介绍了嘉兴电厂1号炉试生产期间结渣对运行参数、机组负荷的影响，详细分析了结渣的原因，井通过风量的细调，组织好炉内切圆燃烧，解决了结渣问题。

Optimization of air quantity regulation in mine ventilation networks using the improved differential evolution algorithm and critical path method

In mine ventilation networks, the reasonable airflow distribution is very important for the production safety and economy. Three basic problems of the natural, full-controlled and semi-controlled splitting were reviewed in the paper. Aiming at the high difficulty semi-controlled splitting problem, the general nonlinear multi-objectives optimization mathematical model with constraints was established based on the theory of mine ventilation networks. A new algorithm, which combined the improved differential evaluation and the critical path method （CPM） based on the multivariable separate solution strategy, was put forward to search for the global optimal solution more efficiently. In each step of evolution, the feasible solutions of air quantity distribution are firstly produced by the improved differential evolu- tion algorithm, and then the optimal solutions of regulator pressure drop are obtained by the CPM. Through finite steps iterations, the optimal solution can be given. In this new algorithm, the population of feasible solutions were sorted and grouped for enhancing the global search ability and the individuals in general group were randomly initialized for keeping diversity. Meanwhile, the individual neighbor- hood in the fine group which may be closely to the optimal solutions were searched locally and slightly for achieving a balance between global searching and local searching, thus improving the convergence rate. The computer program was developed based on this method. Finally, the two ventilation networks with single-fan and multi-fans were solved. The results show that this algorithm has advantages of high effectiveness, fast convergence, good robustness and flexibility. This computer program could be used to solve lar^e-scale ~eneralized ventilation networks o^timization problem in the future.

Genetic Optimization Algorithm of PID Decoupling Control for VAV Air-Conditioning System

Variable-air-volume (VAV) air-conditioning system is a multi-variable system and has multi coupling control loops. While all of the control loops are working together, they interfere and influence each other. A multivariable decoupling PID controller is designed for VAV air-conditioning system. Diagonal matrix decoupling method is employed to eliminate the coupling between the loop of supply air temperature and that of thermal-space air temperature. The PID controller parameters are optimized by means of an improved genetic algorithm in floating point representations to obtain better performance. The population in the improved genetic algorithm mutates before crossover, which is helpful for the convergence. Additionally the micro mutation algorithm is proposed and applied to improve the convergence during the later evolution. To search the best parameters, the optimized parameters ranges should be amplified 10 times the initial ideal parameters. The simulation and experiment results show that the decoupling control system is effective and feasible. The method can overcome the strong coupling feature of the system and has shorter governing time and less over-shoot than non-optimization PID control.

Effect of partial blockage of air duct outlet on performance of OWC device

The use of a Savonius rotor as turbine for an oscillating water column(OWC) is demonstrated.The effect of tuning the OWC using turbine duct blockage is also studied for different wave conditions.A horizontal turbine section OWC employing a Savonius rotor was tested by varying the opening of OWC exit(0%,25%,50%,75% and 100%) to study the behavior and performance of the device.The OWC model was tested at water depth of 0.29 m at frequencies of 0.8,0.9 and 1.0 Hz while the exit openings are varied.The static pressure,dynamic pressure,rotational speed of the Savonius rotor and the coefficient of power are presented as results.The OWC with exit opening of 25% showed greater performance in terms of rotational speed and CP compared to OWC with other exit opening percentages.This proves the ability of the OWC to be tuned by regulating flow in the turbine duct.

Passive control of along-wind response of tall building

Most of modern tall buildings using lighter construction materials with high strength and less stiffness are more flexible, which occurs excessive wind-induced vibration, resulting in occupant discomfort and structural unsafety. It is necessary to predict wind-induced vibration response and find out a method to mitigate such an excessive wind-induced vibration at the preliminary design stage. Recently, many studies have been conducted in using actuator control force based on the linear quadratic optimum control algorithm. It was accepted as a common knowledge that the performance of passive tuned mass damper(TMD) could increase by incorporating a feedback active control force in the design of TMD, which is called active tuned mass damper(ATMD). However, the fact that ATMD is superior to TMD to reduce wind-induced vibration of a tall building is still a question. The effectiveness of TMD for mitigating the along-wind vibration of a tall building was investigated. Optimum parameters of tuning frequency and damping ratio for TMD under a random load which has a white noise spectra were used. Fluctuating along-wind load acting on a tall building treated as a stationary Gaussian random process was simulated numerically using the along-wind load spectra. And using this simulated along-wind load, along-wind responses of a tall building with and without TMD were calculated and the effectiveness of TMD in mitigating the along-wind response of a tall building was found out.

Patient and physician perception of natural orifice transluminal endoscopic appendectomy

AIM:To investigate perception of natural orifice transluminal endoscopic surgery(NOTES)as a potential technique for appendectomy.METHODS:One hundred patients undergoing endoscopy and 100 physicians were given a questionnaire describing in detail the techniques of NOTES and laparoscopic appendectomy.They were asked about the reasons for their preference,choice of orifice,and extent of complication risk they were willing to accept.RESULTS:Fifty patients(50%)and only 21 physicians(21%)preferred NOTES(P<0.001).Patients had previously heard of NOTES less frequently(7%vs73%,P<0.001)and had undergone endoscopy more frequently(88%vs 36%,P<0.001)than physicians.Absence of hernia was the most common reason for NOTES preference in physicians(80%vs 44%,P= 0.003),whereas reduced pain was the most common reason in patients(66%vs 52%).Physicians were more likely to refuse NOTES as a novel and unsure technique(P<0.001)and having an increased risk of infection(P<0.001).The preferred access site in both groups was colon followed by stomach,with vagina being rarely preferred.In multivariable modeling,those with high-school education[odds ratio(OR):2.68,95% confidence interval(CI):1.23-5.83]and prior colonoscopy(OR:2.10,95%CI:1.05-4.19)were more likely to prefer NOTES over laparoscopic appendectomy.There was a steep decline in NOTES preference with increased rate of procedural complications.Male patients were more likely to consent to their wives vaginal NOTES appendectomy than male physicians(P=0.02).CONCLUSION:The preference of NOTES for appendectomy was greater in patients than physicians and was related to reduced pain and absence of hernia rather than lack of scarring.

Design of Control Scheme for Variable Air Volume Air- conditioning System

The air quantity of variable air volume system for the rooms and the total air quantity of the system changes with the change of room load. Combined with the system composition in the laboratory, the paper determines the control scheme of the variable air volume system, that is, indoor temperature-control, indoor positive pressure control, air distribution static pressure control, air-supply temperature control and new air volume control. The dotted lines with arrows mean the output signals from the control unit to actuator, and the solid lines with arrows represent the input signals from the actuator to the control unit.

Study on influence of characteristics of air-supply jet on drain-contamination efficiency and air quality in heading

Based on the theory of air supply jet, the conception and theory of the air quality and the drain contamination efficiency, the results achieved by comparing the circular cross section wall jet with the plane wall jet were following: firstly, within the limitation of the ventilation distance at the tunnel heading in a coal mine, there were a better air quality and a higher efficiency of drain contamination with application of the plane wall jet ventilation. Secondly, there was a advantage to improve the air quality of the workers breathing area with mounting the air supply outlet on the top but not on the side of the tunnel heading.

Airflow adjustment and minimization of the air power of ventilation network

It is often required to know which roadway （adjustment roadway） resistances and how much values of the resis- tances should be changed to make the airflow rates in roadways （target roadways） to certain required values in the practice of mine ventilation. In this case, the airflow rates of the target roadways and the resistances of the roadways other than the ad- justment roadways are the given conditions and the resistances of the adjustment roadways are the solutions to be found. No straightforward method to solve the problem has been found up to now. Therefore, trial and error method using the ventilation network analysis program is utilized to solve the problem so far. The method takes long calculation time and the best answer is not necessarily obtained. The authors newly defined ＂airflow element＂ as an element of the ventilation network analysis. The resistances that satisfy the airflow requirements can be calculated straight forwardly by putting the function of the airflow element into the ventilation network analysis. The air power required for the ventilation can be minimized while meeting the airflow requirements by the advanced application of the method. The authors made the computer program fulfill the method. The program was applied to actual ventilation network and it was found that the method is very practical and the time required for the analysis is short.

Risk Communication： Survey on Quality of Safety Data Sheets of Agricultural Substances

Manufacturers of chemicals are responsible for setting up a list of tools, including labels and safety data sheets, in order to provide adequate information about dangerous properties being labels and safety data sheets the main instruments for the immediate advice about dangerous substances and preparations for general public and workers. While correct labelling gives the possibility to general public to recognise the risks arising from handling and use of dangerous chemicals, safety data sheets are provided for professionals in order to allow safe handling and storage of dangerous chemicals in work places. Information contained in safety data sheets are also designed to suggest safety measures to be taken for the protection of workers as well as precaution measures and adequate actions to be taken in the case of accident. This project has critically revised the information contained in a list of safety data sheets of active ingredients provided for plant protection products, in order to assess the quality and the consistency of the data contained. Reported data have been then compared to published data. Considerable deficiencies/mistakes/inconsistencies have been found in the data reported along the safety data sheets of the examined substances, showing an urgent need of improving the enforcement related to a systematic recognition in this field as well as training of people involved in compilation of safety data sheets by producer side.

Wind Generation Modeling for Transmission Systems Adequacy Studies with Economic Dispatch

In this paper, a strategy is proposed in order to introduce in a realistic way wind generation into a HL11 （bulk power system） non sequential Monte Carlo adequacy study with economic dispatch. Thanks to the implemented solution, wind generation is consequently confronted to operational constraints related to high powered thermal units, nuclear parks or thermal machines with technical minimum value. Moreover, during each simulated system state, a DC load flow is also calculated in order to evaluate reinforcements optimizing the large scale integration of wind power production. The simulation tool modified during the present work is called Scanner and is the property of Tractebel Engineering （Gaz de France-Suez） company. It has been here applied to an academic test system： the Roy Billinton Test System （RBTS）.

大卖场里冬季空调室外、室内冰火两重天，为的是哪般？

针对如今大卖场、大商场之类空间大、人流量大的场所空调系统的设计和运行中普遍存在的不合理现象，提出自己的见解。对照相关设计规范和节能设计标准，指出这些工程的空调系统设计不符合相关的规定要求。明确提出一个观点，即大空间、大人流场所的空调，应该采用全空气式空调系统，而且其室内温度设定值和新风量应该做到全年自动可调，以满足这类场所全年舒适、卫生、节能、经济运行的要求。

Development of a disease-specific health-related quality of life questionnaire for patients with post-stroke spasticity

OBJECTIVE： This study was designed to develop a disease-specific health-related quality of life （HR-QOL） measure for patients with post-stroke spasticity. METHODS; Based on responses from 20 patients with post-stroke spasticity and an extensive literature search, items potentially used to measure these patients＇ recovery status were identified and the Apoplexy Spastic-Paralysis Questionnaire （ASPQ） was formed. A sample of 106 patients was then tested twice using the ASPQ, the Self-rating Depression Scale （SDS） and the Stroke-specific Quality of Life （SS-QOL）. Clinicians also examined all the patients using the Ashworth Scale （AS）. Inter- nal reliability was assessed using Cronbach＇s coeffi- cient a, while construct validity was determined us- ing principal component analysis （PCA）. Empirical validity was evaluated between patients with de- pression and those without depression by single factor analysis. Sensitivity was examined by calcu- lating the Spearman correlation coefficient be- tween the changes in scores of the ASPQ, the AS and the SS-QOL. RESULTS： The ASPQ had adequate internal consis- tency reliability （a=0.874） and sensitivity, with sig- nificant correlations between the changes in scores of the AS, the SS-QOL and the ASPQ, with three do- mains. In a construct validity test, six factors were extracted; the overall variance explained by all fac- tors was 72.6%. For empirical validity, mean values of 19 items and 3 domains were all higher in the de- pressive patients than in the non-depressive pa- tients. CONCLUSION： The ASPQ is a reliable and valid self-rating scale for measuring the HR-QOL in pa- tients with post-stroke spasticity.