Assessment of the Automobile Assembly Paint Process for Energy, Environmental, and Economic Improvement

A coat of paint adds considerable value to an automobile. In addition to consuming up to 60% of the energy needed by automobile assembly plants, however, the painting process also creates both economic and environmental impacts. This study investigated the degree of cost and environmental impact improvement that can be expected when modifications are considered for existing paint processes through heat integration. In order to accomplish this goal, a mathematical model was created to describe the energy use, costs, and environmental impacts from energy consumption in an automobile assembly painting facility. The model agrees with measured energy consumption data for process heating and electricity demand to within about 15% for one Michigan truck facility from which model input parameters were obtained. Thermal pinch analysis determined an energy conservation target of 58% of paint process energy demand. A heat exchanger network optimization study was conducted in order to determine how closely the network design could achieve this target. The resulting heat exchanger network design was profitable based on a discounted cash flow analysis and may achieve reductions in total corporate energy consumption of up to 16% if implemented corporatewide at a major automobile manufacturer.     

Limitations on arteriovenous cooling of the blood supply to the human brain

Arteriovenous heat transfer (AVHT) is a thermoregulatory phenomenon which enhances tolerance to thermal stress in a variety of animals. Several authors have speculated that human responses to thermal stress reflect AVHT in the head and neck, even though primates lack the specialized vascular arrangements which characterize AVHT in other animals. We modeled heat transfer based on the anatonmical relationships and blood flows for the carotid artery and associated venous channels in the human neck and cavernous sinus. Heat transfer rate was predicted using the effectiveness-number of transfer units method for heat exchanger analysis. Modeling showed that AVHT is critically dependent upon (1) heat exchanger effectiveness and (2) arteriovenous inlet temperature difference. Predicted heat exchanger effectiveness is less than 5.5% for the neck and 0.3% for the cavernous sinus. These very low values reflect both the small arteriovenous interface for heat exchange and the high flow rate in the carotid artery. In addition, humans lack the strong venous temperature depression required to drive heat exchange; both the cavernous sinus and the internal jugular vein carry a large proportion of venous blood warmed by its passage through the brain as well as a small contribution from the face and scalp, whose temperature varies with environmental conditions. Under the most optimistic set of assumptions, carotid artery temperature would be lowered by less than 0.1° C during its passage from the aorta to the base of the brain. Physiologically significant cooling of the blood supply to the brain cannot occur in the absence of a suitably scaled site specialized for heat exchange.     

Moderate heat stress reduces the pH component of the transthylakoid proton motive force in light-adapted, intact tobacco leaves

We measured the Δ Ψ and ΔpH components of the transthylakoid proton motive force ( pmf ) in light-adapted, intact tobacco leaves in response to moderate heat. The Δ Ψ causes an electrochromic shift (ECS) in carotenoid absorbance spectra. The light–dark difference spectrum has a peak at 518 nm and the two components of the pmf were separated by following the ECS for 25 s after turning the light off. The ECS signal was deconvoluted by subtracting the effects of zeaxanthin formation (peak at 505 nm) and the qE-related absorbance changes (peak at 535 nm) from a signal measured at 520 nm. Heat reduced ΔpH while Δ Ψ slightly increased. Elevated temperature accelerated ECS decay kinetics likely reflecting heat-induced increases in proton conductance and ion movement. Energy-dependent quenching (qE) was reduced by heat. However, the reduction of qE was less than expected given the loss of ΔpH. Zeaxanthin did not increase with heat in light-adapted leaves but it was higher than would be predicted given the reduced ΔpH found at high temperature. The results indicate that moderate heat stress can have very large effects on thylakoid reactions.     

Reconfigurable control system design for fault diagnosis and accommodation

The growing demand in system reliability and survivability under failures has urged ever-increasing research effort on the development of fault diagnosis and accommodation. In this paper, the on-line fault tolerant control problem for dynamic systems under unanticipated failures is investigated from a realistic point of view without any specific assumption on the type of system dynamical structure or failure scenarios. The sufficient conditions for system on-line stability under catastrophic failures have been derived using the discrete-time Lyapunov stability theory. Based upon the existing control theory and the modern computational intelligence techniques, an on-line fault accommodation control strategy is proposed to deal with the desired trajectory-tracking problems for systems suffering from various unknown and unanticipated catastrophic component failures. Theoretical analysis indicates that the control problem of interest can be solved on-line without a complete realization of the unknown failure dynamics provided an on-line estimator satisfies certain conditions. Through the on-line estimator, effective control signals to accommodate the dynamic failures can be computed using only the partially available information of the faults. Several on-line simulation studies have been presented to demonstrate the effectiveness of the proposed strategy. To investigate the feasibility of using the developed technique for unanticipated fault accommodation in hardware under the real-time environment, an on-line fault tolerant control test bed has been constructed to validate the proposed technology. Both on-line simulations and the real-time experiment show encouraging results and promising futures of on-line real-time fault tolerant control based solely upon insufficient information of the system dynamics and the failure dynamics.     

生态土地分类研究进展

土地分类是土地评价,替代和管理的基础,对林业资源可持续利用具有重要的意义。生态土地分类是目前土地分类的主要方向和趋势。国际上早已开展此项研究。随着景观生态学和3S技术的发展,生态分类系统的研制已成为生态土地分类的重点。本文对生态土地分类的定义,特点,发展历史,生态分类系统理论,以及国际生态分类系统的发展趋势进行了系统的综述,并指出以资源（森林,土地,水域等）多目标管理为基础,定量与定性相结合的多因子多层次综合是未来生态土地研究发展的总趋势,有必要在我国大力开展相关研究。     

中国西北及中亚主要绿洲农区分类

应用生态学原理以水为主线建立绿洲农区树形分类体系,将中国西北及中亚主要绿洲农区采用五级指标分类并进行区划。一级分类指标为水热配合状况,分水热同期型或不同期型;二级指标为水汽主要来源,分西风环流带来水汽型或太平洋季风带来水汽型;三级指标为灌溉水来源,分为"山地-绿洲-荒漠系统"产生河流灌溉型或由"系统"外来河流灌溉型;四级指标为不同河流类型灌溉形成的土壤,分地面河灌溉形成灌淤土型或地下径流(河)井、泉清水灌溉形成灌耕土型;五级指标为地理位置名称及当地的气候带。将分类结果用亿图图示专家软件绘成树形分类图,再用Arc GIS9.3软件制成分类分布图。经分析比较得出:中国西北水热同期型较中亚水热不同期型绿洲农区的光、温、水资源耦合效应更优越。     

Temperature regulation of the testes of the bottlenose dolphin (Tursiops truncatus): evidence from colonic temperatures

Dolphins possess a countercurrent heat exchanger that functions to cool their intra-abdominal testes. spermatic arteries in the posterior abdomen are juxtaposed to veins returning cooled blood from the surfaces of the dorsal fin and flukes. A rectal probe housing a linear array of five copper-constantan thermocouples was designed to measure colonic temperatures simultaneously at positions anterior to, within, and posterior to the region of the colon flanked by the countercurrent heat exchanger. Colonic temperatures adjacent to the countercurrent heat exchanger were maximally 1.3°C cooler than temperatures measured outside this region. Temporary heating and cooling of the dorsal fin and flukes affected temperatures at the countercurrent heat exchanger, but had little or no effect on temperatures posterior to its position. These measurements support the hypothesis that cooled blood is introduced into the deep abdominal cavity and functions specifically to regulate the temperature of arterial blood flow to the dolphin testes.     

A Fault Diagnosis Methodology for Gear Pump Based on EEMD and Bayesian Network

This paper proposes a fault diagnosis methodology for a gear pump based on the ensemble empirical mode decomposition (EEMD) method and the Bayesian network. Essentially, the presented scheme is a multi-source information fusion based methodology. Compared with the conventional fault diagnosis with only EEMD, the proposed method is able to take advantage of all useful information besides sensor signals. The presented diagnostic Bayesian network consists of a fault layer, a fault feature layer and a multi-source information layer. Vibration signals from sensor measurement are decomposed by the EEMD method and the energy of intrinsic mode functions (IMFs) are calculated as fault features. These features are added into the fault feature layer in the Bayesian network. The other sources of useful information are added to the information layer. The generalized three-layer Bayesian network can be developed by fully incorporating faults and fault symptoms as well as other useful information such as naked eye inspection and maintenance records. Therefore, diagnostic accuracy and capacity can be improved. The proposed methodology is applied to the fault diagnosis of a gear pump and the structure and parameters of the Bayesian network is established. Compared with artificial neural network and support vector machine classification algorithms, the proposed model has the best diagnostic performance when sensor data is used only. A case study has demonstrated that some information from human observation or system repair records is very helpful to the fault diagnosis. It is effective and efficient in diagnosing faults based on uncertain, incomplete information.     

A comparison of two fouling‐resistant heat exchangers

Fouling cannot always be prevented; it is important to consider the design of fouling‐resistant heat exchangers. To examine these exchangers, a test fluid whose fouling behaviour is understood should be used. Experiments have been conducted to examine the response of two model systems, a pulsatile flow and a fluid bed heat exchanger, to fouling from whey protein concentrates. Both systems are effective in certain cases, although the enhanced mass transfer possible in the pulsatile flow exchanger can increase fouling when mass transfer controls deposition. This demonstrates the possible danger in installing “antifouling”; systems. The possible mechanisms by which antifouling exchangers operate is discussed; they may work both by slowing the kinetics of fouling or enhancing the heat transfer coefficient. A simple model to demonstrate the design of antifouling exchangers is presented.     

Semiconductor fault detection and classification for yield enhancement and manufacturing intelligence

Process monitoring and profile analysis are crucial in detecting various abnormal events in semiconductor manufacturing, which consists of highly complex, interrelated, and lengthy wafer fabrication processes for yield enhancement and quality control. To address real requirements, this study aims to develop a framework for semiconductor fault detection and classification (FDC) to monitor and analyze wafer fabrication profile data from a large number of correlated process variables to eliminate the cause of the faults and thus reduce abnormal yield loss. Multi-way principal component analysis and data mining are used to construct the model to detect faults and to derive the rules for fault classification. An empirical study was conducted in a leading semiconductor company in Taiwan to validate the model. Use of the proposed framework can effectively detect abnormal wafers based on a controlled limit and the derived simple rules. The extracted information can be used to aid fault diagnosis and process recovery. The proposed solution has been implemented in the semiconductor company. This has simplified the monitoring process in the FDC system through the fewer key variables. The results demonstrate the practical viability of the proposed approach.     

Electroconvulsive Shock Increases α1b-but Not α1a-Adrenoceptor Binding Sites in Rat Cerebral Cortex

Repeated administration of electroconvulsive shock (ECS) increases [3H]prazosin binding to alpha 1-adrenoceptors in rat cerebral cortex. In contrast, [3H]WB4101 binding in cortex has been reported to be unchanged after ECS. [3H]Prazosin labels two alpha 1-adrenoceptor subtypes, termed alpha 1a and alpha 1b, whereas [3H]WB4101 labels the alpha 1a subtype preferentially. The purpose of this study was to determine whether ECS increases one or both alpha 1-adrenoceptor subtypes in rat cerebral cortex. We found that treatment of rats with ECS once daily for 10-12 days increased [3H]prazosin binding in cortex by about 25% but did not significantly alter [3H]WB4101 binding to alpha 1-adrenoceptors. Measurement of alpha 1a and alpha 1b receptors by competition analysis of the selective alpha 1a antagonist 5-methylurapidil against [3H]prazosin and measurement of [3H]prazosin binding in homogenates preincubated with chlorethylclonidine, which alkylates alpha 1b binding sites, also indicated that the ECS-induced increase in alpha 1-adrenoceptors is confined to the alpha 1b subtype. In contrast to its effect on [3H]prazosin binding, ECS did not increase phosphoinositide hydrolysis as measured by [3H]inositol 1-phosphate accumulation in slices of rat cerebral cortex stimulated by either norepinephrine or phenylephrine. The failure of ECS to increase [3H]inositol 1-phosphate accumulation stimulated by phenylephrine, which is a partial agonist for this response, suggests that spare receptors do not account for the apparent absence of effect of ECS on alpha 1-adrenoceptor-mediated phosphoinositide hydrolysis.     

Mechanism of action of physical antipyresis in the rat

To study the mechanism of action of physical antipyresis, core temperature was measured in two groups of rats in which heat loss was increased by cold exposure and by cooling an inferior cava heat exchanger, respectively, both before and after infection with Salmonella enteritidis. Cold exposure did not influence core temperature. On the other hand, cooling the heat exchanger caused a fall in core temperature of approximately 0.7 degree C, to 37 degrees C in normothermia and to 38.5 degrees C 24 h after the infection. These lower core temperatures were then regulated against any further increase in heat loss until the thermoregulatory metabolic capacity of the animals was exhausted and a hypothermia developed. It is concluded that in infectious fever the threshold temperature of shivering increases as much as core temperature. Furthermore it is suggested that physical antipyresis, such as sponging with tepid water, induces a moderate but regulated fall in temperature to about the threshold of shivering and that its efficacy may increase with ambient temperature.     

中国东海微型鞭毛虫群落的分布特征及其环境影响因子

海洋微型鞭毛虫是海洋原生生物中一类高度异质化的类群,物种多样性高,具有多种营养方式,在全球海洋生态系统中占据广阔的生态位,在生物地球化学循环中发挥着关键作用。然而关于其生物多样性和群落结构的认识十分有限,特别是有关环境因子与其生物地理分布关系的研究更为罕见。为了探究微型鞭毛虫群落多样性、群落结构以及影响其生物地理分布格局的环境因素,将高通量测序技术与传统的显微镜观测方法相结合,全面调查了中国东海春季和秋季微型鞭毛虫的群落特征,并深入探讨了与环境因子之间的关系。结果表明：东海微型鞭毛虫的丰度平均为2.27×10~3个/mL,表现为近岸处较高、随离岸距离的增加而下降的趋势;Shannon多样性指数呈现表层低于底层、近岸区低于陆架区的特征,反映了生物群落的稳定程度以及对环境条件的适应程度;不同类群的鞭毛虫具有各自独特的营养模式和相对固定的粒级,表现出对温度、盐度、溶解氧等环境因素的不同响应,从而使群落的物种组成和分布模式呈现明显的季节变化和生境差异。研究结果可为深入认识东海海洋微型鞭毛虫的群落结构、分布格局以及环境影响因素提供理论依据。     

用光合-蒸散耦合模型模拟冬小麦水热通量的日变化

从SPAC理论出发,建立了一个冬小麦光合和蒸散的耦合模型．感热通量和潜热通量采用Shuttleworth-Wallace的双层模型计算,并通过冠层阻力的参数化,将光合作用与蒸腾作用耦合起来．用涡度相关方法,观测了感热通量和潜热通量,对模型进行了验证．结果表明,模拟值与观测值比较一致,模型可以很好地模拟感热通量和潜热通量的日变化过程．对模型的敏感性分析发现,冬小麦蒸腾比较敏感的参数有凋萎点、气孔导度参数、叶对红外辐射的反射率和光响应曲线凸度;土壤蒸发只对土壤阻力参数的敏感性较强．本模型对水热通量与环境因子作用过程的理论研究和指导农田的灌溉制度等有一定的意义．     

Design of a fault-tolerant decision-making system for biomedical applications

This paper describes the design of a fault-tolerant classification system for medical applications. The design process follows the systems engineering methodology: in the agreement phase, we make the case for fault tolerance in diagnosis systems for biomedical applications. The argument extends the idea that machine diagnosis systems mimic the functionality of human decision-making, but in many cases they do not achieve the fault tolerance of the human brain. After making the case for fault tolerance, both requirements and specification for the fault-tolerant system are introduced before the implementation is discussed. The system is tested with fault and use cases to build up trust in the implemented system. This structured approach aided in the realisation of the fault-tolerant classification system. During the specification phase, we produced a formal model that enabled us to discuss what fault tolerance, reliability and safety mean for this particular classification system. Furthermore, such a formal basis for discussion is extremely useful during the initial stages of the design, because it helps to avoid big mistakes caused by a lack of overview later on in the project. During the implementation, we practiced component reuse by incorporating a reliable classification block, which was developed during a previous project, into the current design. Using a well-structured approach and practicing component reuse we follow best practice for both research and industry projects, which enabled us to realise the fault-tolerant classification system on time and within budget. This system can serve in a wide range of future health care systems.     

Extrasynaptic transmission and the diffusion parameters of the extracellular space

Extrasynaptic volume transmission, mediated by the diffusion of neuroactive substances in the extracellular space (ECS), plays an important role in short- and long-distance communication between nerve cells. The ability of a substance to reach extrasynaptic high-affinity receptors via diffusion depends on the ECS diffusion parameters, ECS volume fraction alpha (alpha=ECS volume/total tissue volume) and tortuosity lambda (lambda2=free/apparent diffusion coefficient), which reflects the presence of diffusion barriers represented by, e.g., fine astrocytic processes or extracellular matrix molecules. These barriers channel the migration of molecules in the ECS, so that diffusion may be facilitated in a certain direction, i.e. anisotropic. The diffusion parameters alpha and lambda differ in various brain regions, and diffusion in the CNS is therefore inhomogeneous. Changes in diffusion parameters have been found in many physiological and pathological states, such as development and aging, neuronal activity, lactation, ischemia, brain injury, degenerative diseases, tumor growth and others, in which cell swelling, glial remodeling and extracellular matrix changes are key factors influencing diffusion. Changes in ECS volume, tortuosity and anisotropy significantly affect the accumulation and diffusion of neuroactive substances and thus extrasynaptic transmission, neuron-glia communication, mediator "spillover" and synaptic crosstalk as well as, cell migration. The various changes occurring during pathological states can be important for diagnosis, drug delivery and treatment.     

Combined monitor for direct and indirect measurement of biofouling

Biofouling is one of the most important problems associated with heat exchangers, leading to a loss of thermal performance in their cycle. To maintain them in optimum working condition, biofouling must be kept under control and, to do so, instrumentation is required for its monitoring. The development of the biofouling layer can be qualitatively followed, but only during maintenance shutdown periods is it possible to attain a quantitative assessment. The CMDIMB [Combined Monitor for Direct and Indirect Measurement of Biofouling] was conceived as a means of discovering the evolution of the frictional resistance (f) and the heat transfer resistance (R(f)) of a fluid because these are variables that indirectly define the biofouling deposited in the tubes of a seawater-cooled heat exchanger. They likewise serve to directly indicate its mass and thickness according to the total solid matter adhered over time. The results obtained allowed the values of the variables taken by the CMDIMB to be extrapolated to the heat exchanger that was set up in parallel. The CMDIMB is proposed as a highly useful tool for directly and indirectly monitoring biofouling growth in heat exchangers that do not possess the necessary instrumentation to monitor this phenomenon.