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1.
Response surface methodology is often used by researchers in different fields to determine the optimum values for controlled variables to maximize or minimize the response variables. Either maximization or minimization might be necessary depending on the response property. For example, if the response variable represents the yield of a process, maximization could be necessary; on the other hand, if the response variable is the biological oxygen demand (BOD) of an effluent the aim would definitely be minimization

Response surface methodology can be used two ways. It can be applied to the full-scale production or it can be scaled to a laboratory or the pilot plant. When applied to the full-scale production, the method is known as evolutionary operation (EVOP). EVOP is the continuous optimization of a process. The optimum conditions in a production plant can change depending on many factors such as raw material, ambient temperature, and equipment wear. Therefore, controlled variables should be optimized continuously to keep the response variable as close as possible to the maximum or minimum value. Hence, controlled variables are systematically changed around a center point to depict any shift of the response variable from the extreme. A thorough discussion of EVOP is given by Box, Evolutionary Operation: A Method for Increasing Industrial Productivity, Appl. Statist., 6, 81-101 (1957).  相似文献   
2.
Litchi (Litchi chinensis Sonn.) fruits are very susceptible to pericarp browning which adversely affects consumer acceptability even though the aril portion remains in excellent condition. Litchi arils (litchis) were treated with a solution containing 0–2% (w/v) calcium lactate (CL), 0–0.02% (w/v) 4‐hexyl resorcinol (4‐HR) and 1% potassium sorbate. The pH of solution was adjusted to 4.0 with citric acid. Treated litchis were packed in polystyrene trays, over‐wrapped with polypropylene film, vacuum‐packed (0, 47409.3, 94831.9 Pa) and stored at 4 ± 2 °C. Drip losses, pH, total soluble solids (TSS), sensory attributes and microbiological quality of stored samples were estimated. A four‐factor, three‐level experimental design (D6 Hokes design) with 19 experiments was chosen. Mathematical models were developed to analyse and predict the effect of CL, 4‐HR, in‐package vacuum and storage time on the responses. TSS, pH and sensory scores decreased significantly (P 0.01), whereas drip losses and microbial count increased significantly (P 0.01) with time. Drip loss was significantly (P 0.1) reduced by addition of CL. 4‐HR prevented browning and changes in colour score during storage were significantly less. Vacuum in packages exerted significant (P 0.01) effect over pH, TSS, sensory and microbiological qualities of minimally processed litchis.  相似文献   
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4.
Intelligence has been an object of study for a long time. Different architectures try to capture and reproduce these aspects into artificial systems (or agents), but there is still no agreement on how to integrate them into a general framework. With this objective in mind, we propose an architectural methodology based on the idea of intentional configuration of behaviors. Behavior‐producing modules are used as basic control components that are selected and modified dynamically according to the intentions of the agent. These intentions are influenced by the situation perceived, knowledge about the world, and internal variables that monitor the state of the agent. The architectural methodology preserves the emergence of functionality associated with the behavior‐based paradigm in the more abstract levels involved in configuring the behaviors. Validation of this architecture is done using a simulated world for mobile robots, in which the agent must deal with various goals such as managing its energy and its well‐being, finding targets, and acquiring knowledge about its environment. Fuzzy logic, a topologic map learning algorithm, and activation variables with a propagation mechanism are used to implement the architecture for this agent.  相似文献   
5.
This paper proposes a design methodology for very small databases for the purpose of being hosted by portable devices. Three main differences w.r.t. the traditional design methodologies are introduced: first, the main mobility issues are considered along with data distribution; second, context awareness is included in the data design issues to allow full exploitation of context-sensitive application functionalities; and third, the peculiarities of the storage device  (ss) are taken into account by introducing a logistic phase after the usual conceptual and logical phases. The three aspects together determine the VSDB ambient which is the set of personal and environmental characteristics determining the portion of data that must be stored on the portable device. This paper details the design methodology in its conceptual, logical and logistic phases.  相似文献   
6.
于群  郭剑波 《中国电力》2006,39(1):27-30
电网的大规模互联成为世界范围内电力系统发展的必然趋势。现代电力系统的强非线性和高维等复杂特性,使得传统的理论分析方法已不能较好地分析复杂电网的动态行为及由电网连锁反应故障造成的大面积停电事故的成因。作为科学的方法论,综合集成方法论综合了计算机网络技术、数据融合技术、知识与信息及专家群体智能的各方面优势,其应用在研究方式和工作方式上都突破了传统还原论思想的束缚。从复杂性科学的角度,介绍了复杂电力系统的特征,并着重论述了应用研究复杂系统的方法论——从定性到定量综合集成方法进行电力系统灾变防治研究的方法。  相似文献   
7.
Performance assessment of embedded HW/SW systems built with various types of VLSI components, i.e. heterogeneous multi-processor architectures, is important to help the development of complex real-time applications. To design such a tool, two issues must be solved: the gathering of relevant information simultaneously on several components without disturbing the application behavior, display of the performance results in a way that can be easily interpreted by designers. This paper presents a significant solution for the two above issues. We first describe what the goal for designers is and what kind of applications are concerned. Then we describe the principle of collecting an event trace and the technique to evaluate the selected performance indexes. The monitoring technique, based on a specific ASIC, is non-intrusive and allows our tool to capture real-time event occurrences from software tasks, and even from hardware functions implemented in ASICs. Each event is automatically time-stamped, collected and processed in real-time to evaluate the performance indexes selected by the designer. We also describe the display tool which clearly shows the results to the designer according to different representations. This technique and the associate real-time performance analyzer are integrated in a complete development process based on the MCSE methodology.  相似文献   
8.
谭云涛  郭波 《兵工学报》2007,28(6):761-764
以费用为独立变量( CAIV)方法是美国国防部采用的一项用于对新型武器装备作战效能、费用和性能参数进行综合优化,确定寿命周期内各阶段费用目标并进行费用控制的装备采办方法。在新研武器的系统论证中,CAIV方法的定量决策的关键技术包括建立系统的性能、费用模型,进行权衡研究,并确定寿命周期各阶段的费用目标。文中对这些关键技术进行了研究,并进行了研究展望。  相似文献   
9.
This paper proposes a new quantitative and systematic design methodology for high-speed interpolation/ averaging ADCs. The methodology consists of a new mathematical BW/gain model derived from the pre-amps arrays static model and new small-signal model, a new offset modeling mechanism that can accurately estimate and help to reduce the offset, and hence a new systematic design flow. The methodology enables a quantitative and systematic analysis, conducts iterative and accurate calculation realized in MATLAB, and finally leads to an optimized ADC design that reaches a guaranteed optimum full-chip performance with given specs (i.e., resolution, speed, input range, power, input CM, etc.). The methodology shows significant advantage over the traditional trial-and-error ADC design approach with respect to performance and design efficiency, and is much more reliable in nanometer technologies. The proposed methodology was fully validated in silicon: a 4-bit 5GSps interpolation/averaging ADC is fabricated in a 65 nm CMOS technology and the measurement results show that our ADC has indeed achieved an outstanding and comparable overall performance compared to reported state-of-the art ADCs.  相似文献   
10.
This article aims to give an overview of the Taguchi methodology and more specific of its key step: parameter design. The purpose of parameter design is to bring quality into the product/process by determining the relevant parameters and their optimal settings such that the quality characteristics of the product are optimised and have minimal sensitivity to “noise” (i.e., those disturbing factors which are difficult or too expensive to control). The (mainly statistical) tools used in the methodology will be handled and some actual Bell cases will be mentioned as practical examples.  相似文献   
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