浅析消防联动控制系统设计

分析介绍了消防水泵、电动防火卷帘、防烟排烟设施、非消防电源断电、电梯等设施的联动控制系统的设计方法，并提出了设计中应注意的问题和合理化建议。     

氧化铝系统汽水平衡的改造措施

本通过对中铝山西分公司氧化铝生产系统的汽水系统进行分析计算，指出搞好氧化铝系统的汽水平衡在实际生产中对降低氧化铝汽耗、水耗具有非常重要的作用，同时可以取得可观的经济效益。     

高线厂净循环水系统清洗预膜的实施

在高线厂净循环水系统投入运行之前，进行了管网及设备的清洗与预膜工作，使高线生产具备了良好的运行条件。     

无填料喷雾冷却塔的发展及改进思路

介绍了无填料喷雾冷却塔的发展过程，与传统的填料式冷却塔的结构和冷却效果进行比较，针对喷雾冷却塔结构上的缺点，提出几点改进思路。     

Describing Near Surface, Transient Flow Processes in Unconfined Aquifers below Irrigated Lands: Model Application in the Western San Joaquin Valley, California

In order to rigorously examine near surface, field to field interactions between irrigation management regimes and a shallow fluctuating water table, an enhanced deforming finite element (DFE) model was recently developed. The enhanced DFE model, through a process of iteration within each time step, avoids making common assumptions regarding the changing geometry of an aquifer free surface. This paper demonstrates the usefulness and effectiveness of the model by employing it to an irrigated region in the western San Joaquin Valley, Calif., where shallow subsurface tile drains have been installed to control shallow water tables. By virtue of the problems created by the need to dispose off the drainage water, this region has been the focus of several important regional scale modeling exercises, which have evaluated the utility of management strategies, such as source control, groundwater pumping, and land retirement. By refining the focus of the analysis, the enhanced DFE model is found to be able to show that both sources control and managed pumping could be more effective drainage control strategies than predicted based on the results of regional models.     

Oil Spill Dispersant Effectiveness Protocol. I: Impact of Operational Variables

The current U.S. Environmental Protection Agency protocol for testing the effectiveness of dispersants, the swirling flask test, has been found to give widely varying results in the hands of different testing laboratories. The sources of the ambiguities in the test were determined by considering several options in a rigorous systematic fashion. Options considered were variability among three operators and the variability and limitations of three analytical instruments in establishing a calibration curve for oil/dispersant mixtures. Other options included flask type, impact of operational variables (rotational speed, mixing time, settling time, and oil:dispersant ratio), development of a revised procedure for dispersant effectiveness, reproducibility and repeatability of the revised procedure, and development of selection criteria for screening of dispersants. A redesign of the test flask, which is characterized by having baffles with a stopcock at the bottom for sample collection, was deemed necessary to accomplish reproducibility within operator and between operators. The results indicated that the baffled flask provided a total coefficient of variation (variations within operator and between operators) less than 11% compared to above 100% in some cases for the swirling flask.     

Oil Spill Dispersant Effectiveness Protocol. II: Performance of Revised Protocol

The current U.S. Environmental Protection Agency (EPA) protocol for testing the effectiveness of dispersants for use in treating oil spills on the open water, the swirling flask test (SFT), has been found to give widely varying results in the hands of different testing laboratories. Part I addressed the sources of the ambiguities in the EPA SFT and the development of a new test referred to as the baffled flask test (BFT). In this part of the series, further experiments were conducted for estimating the repeatability of three operators in determining the effectiveness of 18 dispersants by both the EPA SFT and the BFT methods. Overall statistical analysis of the results indicated that the coefficient of variation by the BFT was only 7.8% compared to 21.9% for the EPA SFT. The mean percent effectiveness of the EPA SFT was only 19.7% as compared to 64.6% for the BFT. Proposed selection criteria for screening of dispersants for listing on the National Contingency Plan Product Schedule have been developed.     

Comparative Analysis of Chlorine Dioxide, Free Chlorine and Chloramines on Bacterial Water Quality in Model Distribution Systems

Drinking water utilities may be required to change disinfectant to improve water quality and meet more stringent disinfection regulations. This research was conducted to assess and compares chlorine dioxide to free chlorine and chloramines on bacterial water quality monitored within model distribution systems (i.e., annular reactors). Following colonization with nondisinfected water, annular reactors containing either polycarbonate or cast iron coupons were treated with free chlorine, chlorine dioxide or chloramines. Two disinfectant doses (low/high) were tested for each disinfectant. Under specific environmental conditions, bacterial inactivation varied as a function of the disinfectant type and dose, sample type (bulk water versus biofilm bacteria) and coupon material. The ranking by efficiency was as follows: chlorine dioxide > chlorine > chloramines. On preformed biofilms of 106–107?cfu/cm2, the continuous application of a disinfectant led to a log removal of heterotrophic bacteria concentrations for suspended and biofilm bacteria ranging from 1.1 to 4.0, and from 0.2 to 2.5, respectively. Doubling the amount of disinfectant doses led to an additional log inactivation of 1–2.5 of heterotrophic bacteria levels. This study demonstrates that bacterial inactivation in distribution systems is governed by various inter-related parameters. The data indicate that chlorine dioxide represents a viable alternative for secondary disinfection in distribution systems.     

Soil Water Content and Dry Density by Time Domain Reflectometry

Soil water content and dry density are two important properties for compaction quality control. This paper presents a new method for determining soil water content and dry density using a single time domain reflectometry test, which is an improvement over that designated by ASTM D6780. This new method is based on simultaneous measurement of apparent dielectric constant and bulk electrical conductivity on the same soil sample. Calibration equations correlate these two parameters with soil gravimetric water content and dry density, which are simultaneously solved after adjusting field-measured conductivity to a standard conductivity. The method compensates for temperature effects. The test process takes about 3 min and all calculations are automated. Testing may be done in situ using a special probe that provides sufficient sampling volume or in a compaction mold adapted to form a probe. Laboratory and field tests results show this one-step method is a fast, accurate, and safe method for construction quality control.     

Axial offset control of PWR nuclear reactor core using intelligent techniques

Improved load following capability is one of the main technical performances of advanced PWR (APWR). Controlling the nuclear reactor core during load following operation encounters some difficulties. These difficulties mainly arise from nuclear reactor core limitations in local power peaking, while the core is subject to large and sharp variation of local power density during transients. Axial offset (AO) is the parameter usually used to represent of core power peaking, in form of a practical parameter. This paper, proposes a new intelligent approach to AO control of PWR nuclear reactors core during load following operation. This method uses a neural network model of the core to predict the dynamic behavior of the core and a fuzzy critic based on the operator knowledge and experience for the purpose of decision-making during load following operations. Simulation results show that this method can use optimum control rod groups maneuver with variable overlapping and may improve the reactor load following capability.