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1.
The CSD database contains a list of microorganisms involved in biological fixation of carbon dioxide. The database allows managing of information related to carbon dioxide fixation utilizing microbes belonging to four different classes i.e. microorganisms, genus listing, mechanisms and literature. The database can help in devising biological strategies for reducing carbon dioxide from the environment. It can also serve as comprehensive knowledgebase to search the microbes capable of utilizing carbon dioxide.  相似文献   

2.
Labscape: a smart environment for the cell biology laboratory   总被引:2,自引:0,他引:2  
Labscape is a smart environment that we designed to improve the experience of people who work in a cell biology laboratory. Our goal in creating it was to simplify, laboratory work by making information available where it is needed and by collecting and organizing data where and when it is created into a formal representation that others can understand and process. By helping biologists produce a more complete record of their work with less effort, Labscape is designed to foster improved collaboration in conjunction with increased individual efficiency and satisfaction. A user-driven system, although technologically conservative, embraces a central goal of ubiquitous computing: to enhance the ability to perform domain tasks through fluid interaction with computational resources. Smart environments could soon replace the pen and paper commonly used in the laboratory setting.  相似文献   

3.
Laboratories today face increasing pressure to automate their operations as they are challenged by a continuing increase in workload, need to reduce expenditure, and difficulties in recruitment of experienced technical staff. Was the implementation of a laboratory automation system (LAS) in the Clinical Biochemistry Laboratory at Singapore General Hospital successful? There is no simple answer, so the following topics comparing and contrasting pre- and post-LAS have been explored: turnaround time (TAT), laboratory errors, and staff satisfaction. The benefits and limitations of LAS from the laboratory experience were also reviewed. The mean TAT for both stat and routine samples decreased post-LAS (30% and 13.4%, respectively). In the 90th percentile TAT chart, a 29% reduction was seen in the processing of stat samples on the LAS. However, no significant difference in the 90th percentile TAT was observed with routine samples. It was surprising to note that laboratory errors increased post-LAS. Considerable effort was needed to overcome the initial difficulties associated with adjusting to a new system, new software, and new working procedures. Although some of the known advantages and limitations of LAS have been validated, the claimed benefits such as improvements in TAT, laboratory errors, and staff morale were not evident in the initial months.  相似文献   

4.
Understanding how technical artefacts are created and used within organizations is a central aspect of the IS research discipline. The conduct of research in an organizational setting is thus a major issue for the IS community. A research framework for in-context IS research is presented and used to position purified and hybrid forms of research method. From the framework theoretical support for an `action case' research method is presented. Two IS research cases are presented and analyzed using the IS research framework, leading to a practice-based rationale for an action case method. Characteristics of the action case method, a hybrid of interpretation and intervention, are described. Learning at three levels of analysis—concrete, general, and meta—is proposed and used as a way of reflecting on IS research methods and IS research frameworks.  相似文献   

5.
This paper introduces a knowledge based expert system designed to address the fundamental problem of inventory control (how much of an item to order and how often to order) faced by many managers. It provides implementation details about the structure of the system and its programming environment, OPS5.  相似文献   

6.
In this paper a simulation model is presented to study different machine assignment policies in a multistage, multifacility and multiproduct production inventory system (MS-MF-MP-P1S). The system considered in the present research is the same as reported in the companion paper by Gunasekaran ei al. (1990). The system is modelled based on the ‘discrete event simulation’ approach. The purpose of this simulation model is to enrich the modelling exercise, validate the results of the mathematical model reported in the companion paper and incorporate more realistic decision-making capabilities, such as machine assignment policies, etc. Numerical results are presented to explain the application of the simulation model.  相似文献   

7.
Transfusion of red blood cells (RBCs) is essential for different medical conditions such as surgery, anemia, and cancer. Blood is a precious living composition consisting of eight types of RBCs that can be transfused by either exact or compatible substitutes. As stored blood gets older, it begins to deteriorate; therefore, excessive blood supply at hospitals results in spoilage, while limited supply results in shortage. This research aims at finding the optimal order-up-to-level quantities of blood, which minimize its shortage and outdated units. Stochastic demand, blood aging, emergency orders, and compatibility preference are considered in this study. A customized simulated annealing algorithm is built for optimization. Several simulation experiments are conducted to test the merits of the model in a selected hospital. Not only does the model demonstrate improved results in the mean inventory/age, shortage/spoilage, and substitution percentage but it also serves as a test bed for better understanding of RBC inventory behavior under different compatibility policies.  相似文献   

8.
Inventory centralization for multiple stores with stochastic demands reduces costs by establishing and maintaining a central ordering/distribution point. However the inventory centralization may increase the transportation costs since either the customer must travel more to reach the product, or the central warehouse must ship the product over longer distance to reach the customer. In this paper, we study a partially centralized inventory system where multiple central warehouses exist and a central warehouse fulfills the aggregated demand of stores. We want to determine the number, the location of central warehouses and an assignment of central warehouses and a set of stores. The objective is the minimization of the sum of warehouse costs and transportation cost. With the help of the regression approximation of cost function, we transform the original problem to more manageable facility location problems. Regression analysis shows that the approximated cost function is close to the original one for normally distributed demands.  相似文献   

9.
In this paper we deal with the integrated supply chain management problem in the context of a single vendor-single buyer system for which the production unit is assumed to randomly shift from an in-control to an out-of-control state. At the end of each production cycle, a corrective or preventive maintenance action is performed, depending on the state of the production unit, and a new setup is carried out. Two different integrated production, shipment and maintenance strategies are proposed to satisfy the buyer’s demand at minimum total cost. The first one suggests that the buyer orders batches of size nQ and the vendor produces nQ and makes equal shipments of size Q. The second policy proposes that to satisfy the same ordered quantity, the vendor produces separately smaller batches of size Q, n times. The total integrated average cost per time unit corresponding to each strategy is considered as the performance criterion allowing choosing the best policy for any given situation.  相似文献   

10.
This paper considers a two-stage supply chain, consisting of a single warehouse and multiple retailers facing deterministic demands, under a vendor-managed inventory (VMI) policy. It presents a two-phase optimisation approach for coordinating the shipments in this VMI system. The first phase uses direct shipping from the supplier to all retailers to minimise the overall inventory costs. Then, in the second phase, the retailers are clustered using a construction heuristic in order to optimise the transportation costs while satisfying some additional restrictions. The improvement of the system's performance through coordinated VMI replenishments against the system with direct shipping only is shown and discussed in the comparative analysis section.  相似文献   

11.
A batch production-inventory system consisting of multiple stages with an optimal policy of set-up time reduction and a fixed increment cost are discussed. The ratio of set-up time reduction as a decision variable under various cases of demand in the batch production-inventory model is considered. The ratio of set-up time reduction and lot size are solved simultaneously to obtain an optimal value of the total annual cost. A numerical example is presented to demonstrate the accuracy of the proposed method.  相似文献   

12.
This paper proposes a two-echelon inventory model for a periodical commodity, in which the market and manufacturing channels are combined. This model can be used to solve the production policy, the order policies of the raw materials for the manufacturer, and order size for the retailer. By assuming that the retailers’ demand obeys normal distribution and that the retailer makes orders according to the Newsboy Rule, we derive the necessary and sufficient conditions for the optimal solution of production size, wholesale price, and replenishment cycle of raw materials for the manufacturer. Also, the necessary condition is explored in order to gain managerial insights and economic implications based on numerical examples and sensitivity analysis.  相似文献   

13.
Reinforcement learning (RL) appeals to many researchers in recent years because of its generality. It is an approach to machine intelligence that learns to achieve the given goal by trial-and-error iterations with its environment. This paper proposes a case-based reinforcement learning algorithm (CRL) for dynamic inventory control in a multi-agent supply-chain system. Traditional time-triggered and event-triggered ordering policies remain popular because they are easy to implement. But in the dynamic environment, the results of them may become inaccurate causing excessive inventory (cost) or shortage. Under the condition of nonstationary customer demand, the S value of (T, S) and (Q, S) inventory review method is learnt using the proposed algorithm for satisfying target service level, respectively. Multi-agent simulation of a simplified two-echelon supply chain, where proposed algorithm is implemented, is run for a few times. The results show the effectiveness of CRL in both review methods. We also consider a framework for general learning method based on proposed one, which may be helpful in all aspects of supply-chain management (SCM). Hence, it is suggested that well-designed ‘‘connections” are necessary to be built between CRL, multi-agent system (MAS) and SCM.  相似文献   

14.
This paper is about the study of a production lot sizing problem consisting of customers, one retailer, and one manufacturer. Demand from customers arrives randomly at a retailer one unit at a time. The retailer replenishes inventory from the manufacturer upon receiving a customer's order after its inventory depleted to zero. The manufacturer's production rate is assumed to be a finite constant. A production cycle starts when the manufacturer's inventory falls to or below zero and stops when its on-hand inventory reaches its optimal level. During the uptime in a production cycle, inventory is being built while randomly arriving orders from retailer are being fulfilled. The order arrival times from customers are independently and identically distributed, hence the inventory processes at both the manufacturer and the retailer become a renewal process that is difficult to solve analytically for a general distribution of order arrival time. Therefore, a numerical approach is used in developing a search procedure to obtain the optimal solution to the problem. Employing such a numerical approach, we also investigate how optimal solutions in different cases will change over the spectrum of some key parameters of the problem.  相似文献   

15.

AMACOIA (approche multiagents pour la conception d'installations d'assemblage) is a tool for designing flexible assembly lines. Its objective is to determine the functional specifications of the equipment (manipulators, fixtures, grippers, conveyors, etc.) and the organizational structure (cells, workstations) for the least expensive assembly line able to assemble a product (or a family of products) within the contract cycle time. The design process is implemented by two interacting multiagent systems. One searches through the assembly sequence space, and the other searches through the assembly line space. The resulting assembly line is built by negotiation and self-organization of the agents. Both multiagent systems are regulated by simulated annealing to optimize the technological cost of the assembly line.  相似文献   

16.
付明柏 《软件》2011,32(8):15-17
本文是一个基于C/S(Client/Server)模式、采用Visualc++作为前台开发工具、SQLServer2000作为后台数据库的仓库物资管理系统。文章从系统需求分析、系统的总体框架、业务支撑平台以及实现方式入手,详细介绍了系统的基本信息管理(含客户、仓库和用户等各项信息)、产品信息管理、库存操作管理和库存警示管理等四个主要模块的实现过程。系统通过试运行,实现了预期的各项功能,达到了较为理想的效果。  相似文献   

17.
This article presents two models for determining an optimal integrated economic order quantity and economic production quantity policy in a recoverable manufacturing environment. The models assume that the unit production time of the recovery process decreases with the increase in total units produced as a result of learning. A fixed proportion of used products are collected from customers and then recovered for reuse. The recovered products are assumed to be in good condition and acceptable to customers. Constant demand can be satisfied by utilising both newly purchased products and recovered products. The aim of this article is to show how to minimise total inventory-related cost. The total cost functions of the two models are derived and two simple search procedures are proposed to determine optimal policy parameters. Numerical examples are provided to illustrate the proposed models. In addition, sensitivity analyses have also been performed and are discussed.  相似文献   

18.
Small-scale experiments allow to reproduce and understand phenomena and to draw inferences about large-scale processes. In this paper, we consider a peculiar experimental apparatus which is aimed at reproducing a typical lagoonal environment subject to tidal forcings. This apparatus is useful for performing morphometric analyses of synthetic tidal networks. The quality of these kind of experiments strongly depends on the behaviour of the artificial tide that has to exhibit predefined characteristics. To this aim, the height of the artificial water wave is controlled in real-time. The experimental apparatus has an intrinsic complexity and it represents an example of a multi-domain physical system. In order to design and to assess suitable control strategies, we have developed a Matlab-based simulation environment which is able to reproduce the behaviour of the artificial tide generation system. The dynamic model is calibrated and validated by using real experimental data and it can be seen as an extremely useful tool in the decision making process of the real control system development. In particular, we have designed, tuned, and tested a model-free control algorithm, that is the intelligent-PI (i-PI). Finally, the proposed controller has been implemented on a real-time hardware and then its performance has been compared with that of a standard regulator for different type of experiments.  相似文献   

19.
This study addresses a strategic design problem for bicycle sharing systems incorporating bicycle stock considerations. The problem is formulated as a hub location inventory model. The key design decisions considered are: the number and locations of bicycle stations in the system, the creation of bicycle lanes between bicycle stations, the selection of paths of users between origins and destinations, and the inventory levels of sharing bicycles to be held at the bicycle stations. The design decisions are made with consideration for both total cost and service levels (measured both by the availability rate for rental requests at the pick-up rental stations and coverage of the origins and destinations). The optimal design of this system requires an integrated view of the travel costs of users, bicycle inventory costs and facility costs of bicycle stations and bicycle lanes as well as service levels. The purpose of this study is to create a formal model that provides such an integrated view, and to develop methods for obtaining solutions for the design variables in practical situations. The complexity of the problem precludes the exact solution of the optimization problem for instances of realistic size, and so we propose a heuristic method for efficiently finding near-optimal solutions. In the test problem for which enumeration is possible, the heuristic solution is within 2% optimal. Finally, a numerical example is created to illustrate the model and proposed solution algorithm.  相似文献   

20.
ENDO-LAB is an IBM PC-based system which performs calculations and record-keeping for the Vanderbilt University Medical Center Endocrinology Laboratory. It manages maintenance and quality control, and prints reports for regulatory agencies. The system was designed to minimize paperwork without changing laboratory procedures in any way. Key features of ENDO-LAB include a uniform user interface, and error detection mechanisms. The system is designed to detect data which has been incorrectly entered. In addition, where the efficacy of a test can be determined on the basis of limited data, preliminary graphs are screened as soon as possible, so that the user can terminate lengthy calculations whose outcome would be invalid or inconclusive. ENDO-LAB is an integrated system in that the same statistical and calibration programs can be applied to all of the analyses. The system is both extensible and portable; it has been successfully implemented outside Vanderbilt.  相似文献   

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