Modeling Synergy and Learning under Multiple Advanced Manufacturing Technologies

The advent of the wide variety of new, highly integrated, advanced manufacturing technologies available for acquisition by a firm's managers has brought to light an accompanying set of unexpected issues. These issues include expectations for the benefits and costs of these technologies, determining the appropriate order of implementation and finding a way to justify acquisition when many of the benefits are a function of the technology's learning and synergistic effects on other operations and technologies. We present here a model that captures the interaction effects of these highly integrated technologies and discuss the data requirements for application of the construct. We then illustrate the model's workings with a number of multitechnology examples and show the danger of ignoring the synergistic and learning effects of these technologies when considering their acquisition.     

Efficient Heuristics for MRP Lot Sizing with Variable Production/Purchasing Costs*

Two heuristics based on branch and bound (B&B) are developed to solve closed-loop material requirements planning (MRP) lot-sizing problems that have general product structures and variable costs. A “look ahead method'’(LAM) heuristic allows for variable production/purchasing costs and uses a single-level B&B procedure to rapidly improve lower bound values; thus, LAM efficiently uses computer-storage capacity and allows solution of larger problems. The “total average modification'’(TAM) heuristic uses B&B, applied level by level, and modified setup and carrying costs to solve the variable production/purchasing costs MRP lot-sizing problem. LAM and TAM are tested on problems and compared to heuristics in the literature. TAM may be used to solve large MRP lot-sizing problems encountered in practice.     

A measure of community members’ perceptions of the impacts of research partnerships in health and social services

Currently, there are no psychometrically sound outcome measures by which to assess the impacts of research partnerships. This article describes the development of a 33-item, survey questionnaire measuring community members’ perceptions of the impact of research partnerships addressing health or social issues. The Community Impacts of Research Oriented Partnerships (CIROP) was developed using information from the literatures on health promotion, community development, research utilization, and community-based participatory research, and from focus groups involving 29 key informants. Data from 174 community members were used to determine the factor structure, internal consistency, and test–retest reliability of the four CIROP scales, and to provide evidence of construct validity. The CIROP informs research partnerships about the extent of their impact in the areas of Personal Knowledge Development, Personal Research Skill Development, Organizational/Group Access To and Use of Information, and Community and Organizational Development, allowing them to demonstrate accountability to funding bodies. As well, the CIROP can be used as a research tool to assess the effectiveness of knowledge sharing approaches, determine the most influential activities of research partnerships, and determine structural characteristics of partnerships associated with various types of impact. The CIROP provides a better understanding of community members’ perspectives and expectations of research partnerships, with important implications for knowledge transfer and uptake.     

The praxis of ethnic studies: transforming second sight into critical consciousness

This article focuses on a youth participatory action research (YPAR) program called the Social Justice Education Project (SJEP) that fostered young people of color’s critical consciousness. Their critical consciousness emerged through praxis (reflection/action) while focusing on preserving ethnic studies in Tucson, Arizona. Because the SJEP home was in ethnic studies, the youth also struggled to keep their program alive. The Arizona Department of Education claimed the program bred ‘radicals’ who wanted to overthrow the government and therefore lobbied the state legislature to ban K-12 ethnic studies in public schools. In January 2012, the ban went into effect, shutting down ethnic studies classes as well as the SJEP. Young people’s qualitative research on their struggle led to action to save the education that gave them hope for a more equitable and just world. The article addresses the praxis of YPAR, which sparks a thought process leading to the drive to take action. Observing and documenting educational injustices inspire the need to seek radical change of Self and schools. Through the reflection and action facilitated by YPAR, young people of color construct a message about the importance of ethnic studies for individual as well as social transformation.     

On the Joint Lot-Sizing Problem with Zero Setup Costs

In a recent paper, Pinto and Mabert [5] presented a lot-sizing rule and an improvement procedure for the joint lot-sizing problem with zero setup costs. We show that this procedure often yields infeasible schedules. We also present and discuss two interesting properties of the joint lot-sizing problem with zero setup costs. A numerical example to illustrate the second property is provided.     

关于当前中国农村养老问题及其研究的思考

作为社会的一员 ,老年人有获得社会扶养的权利。如果这种权利不能实现或不能很好实现 ,便形成养老问题。养老问题的研究只能是以认识老年人获得社会保障权利实现过程中的问题并为之谋求对策为根本目的。从这个角度出发 ,养老问题应涵盖四个方面的内容 :(1)“谁来养”的问题 ;(2 )“养不养”的问题 ;(3)“怎么养”的问题 ;(4 )“养得怎么样”的问题。目前 ,这四个方面的问题在农村都存在。而此前的研究因被置于计划生育和老龄化等背景之下而显得不力及过于偏狭 :有限的研究集中于老龄化条件下农村老年人“谁来养”和“怎么养”的问题。这种状况不利于对农村养老问题的全面认识和解决。故笔者认为 ,今后应 (1)全面研究农村养老问题 ;(2 )重视现实 ,分清层次 ,切实研究急需解决的问题 ;(3)在社会变迁的视野下加强农村经济发展、社区建设、文化培育与养老关系的研究     

On the mode of administering a questionnaire and responses to open-ended items

Concurrently administered personal and telephone surveys are compared to measure differences between the modes for identical questions. Speed of questioning is found to be greater in telephone interviews than personal interviews. The faster pace of telephone interviews is linked to shorter answers to open-ended items on the telephone. The tendency to reduce such responses is disproportionately exhibited by younger, affluent respondents who tend to provide detailed responses in personal interviews.     

IMPLICIT OPTIMAL AND HEURISTIC LABOR STAFFING IN A MULTIOBJECTIVE,MULTILOCATION ENVIRONMENT*

This paper presents a tractable set of integer programming models for the days-off scheduling of a mix of full- and part-time employees working α to β days/week (cycle) in a multiple-objective, multiple-location environment. Previous models were formulated to specifically schedule part-time employees working either two or three days per week. These models were intractable because they required complete employee schedule information. The new models are deemed implicit optimal since they are required to supply only essential information. While the number of variables in previous models is an exponential increasing function of β-α, the size of three of the new models is independent of α and β. The first three models developed here (as in [18]) deal with the trade-offs between idle time, the number of employees required to work at multiple “locations,” and the size of the total labor pool. The inherent flexibility of the implicit modeling approach is illustrated by the presentation of various modifications of the basic models. These modifications permit the use of preference weights on the number of employee work days/week (cycle) or the minimization of payroll costs where differential pay rates exist. These latter models may also be formulated such that idle time is ignored, constrained or minimized. The execution time for the implicit models (on a CDC CYBER 730 computer with commercially available software) averaged well under five seconds on 1200 trial problems for the type of application considered in [18]. A solution was obtained in less than 46 seconds of CPU time for a trial problem which would have required over 1.4 million integer variables with previous models. The availability of optimal solutions was invaluable in the development of two heuristics designed to deal with the trade-offs of [16]. In an experimental analysis a previous heuristic produced results which averaged from 74 to 508 percent above optimum across six experimental conditions. The comparable new heuristic produced results which averaged from 3 to 8 percent above optimum for the same experimental conditions. The paper concludes by developing a framework to integrate the results of this research with the tour scheduling problem and by identifying several other areas for related research.     

SCHEDULING PARALLEL PROCESSORS WITH SETUP COSTS AND RESOURCE LIMITATIONS

An integer linear programming model is presented for the scheduling of n products on m identical machines. The particular problem studied is one that occurs frequently in the fiberglass and textile industries. The model incorporates setup costs, lost production costs, and overtime costs. Due to the structure of the model, integer solutions can be obtained by explicitly restricting only a small number of the integer variables. This allows those responsible for scheduling to solve realistically sized problems in an efficient manner. Computational results are provided for a set of generated test problems.