An enhanced approximation mathematical model inventorying items in a multi-echelon system under a continuous review policy with probabilistic demand and lead-time

An inventory system attempts to balance between overstock and understock to reduce the total cost and achieve customer demand in a timely manner. The inventory system is like a hidden entity in a supply chain, where a large complete network synchronizes a series of interrelated processes for a manufacturer, in order to transform raw materials into final products and distribute them to customers. The optimality of inventory and allocation policies in a supply chain for a cement industry is still unknown for many types of multi-echelon inventory systems. In multi-echelon networks, complexity exists when the inventory issues appear in multiple tiers and whose performances are significantly affected by the demand and lead-time. Hence, the objective of this research is to develop an enhanced approximation mathematical model in a multi-echelon inventory system under a continuous review policy subject to probabilistic demand and lead-time. The probability distribution function of demand during lead-time is established by developing a new Simulation Model of Demand During Lead-Time (SMDDL) using simulation procedures. The model is able to forecast future demand and demand during lead-time. The obtained demand during lead-time is used to develop a Serial Multi-echelon Inventory (SMEI) model by deriving the inventory cost function to compute performance measures of the cement inventory system. Based on the performance measures, a modified distribution multi-echelon inventory (DMEI) model with the First Come First Serve (FCFS) rule (DMEI-FCFS) is derived to determine the best expected waiting time and expected number of retailers in the system based on a mean arrival rate and a mean service rate. This research established five new distribution functions for the demand during lead-time. The distribution functions improve the performance measures, which contribute in reducing the expected waiting time in the system. Overall, the approximation model provides accurate time span to overcome shortage of cement inventory, which in turn fulfil customer satisfaction

THE ROLE OF UNDERLYING MECHANISMS IN ACHIEVING CONSISTENT HYBRID COMBINATIONS OF COMPETITIVE ADVANTAGES

This thesis takes a step beyond the current discussion on hybrid competitive strategies (HS) by identifying the underlying mechanisms and common elements of successful hybrid strategies. Reviewing empirical and theoretical literature revealed a significant gap in this respect. Therefore, the activity-based view of strategy is introduced to the discussion on HS. In a first step, four consistent and sustainable HS concepts are developed providing the basis for deriving specific HS models. A second step identifies commonalities among these HS types and theoretically derives a synthesized, common HS model. Thirdly, the critical realist stance was selected for answering this thesis’ research questions addressing consistent HS concepts, implementations, common activities achieving external and internal fit, as well as common capabilities and resources supporting these activities. In a case study approach, semi-structured, open ended interviews combining appreciative and laddering methods are conducted with twelve interviewees from five firms. The separate analysis of ladder elements and ladders allowed distinguishing constitutional from relational elements. Based on this, fourth, an empirically revised research construct is substantiated. This research finds HS firms applying intended and consistent, but mixed strategy concepts based on generating high customer benefits through combining competitive weapons of differentiation and price or total customer cost. Moreover, HS concepts centre on three strategic building blocks: customer centricity, fulfilment of customer needs and employee orientation. Additionally, the research indicates that firms apply activities primarily for achieving fit. While all firms combine both views, no activities are directed to both fit types simultaneously. Activities deploy capabilities and resources in general on two adaptive and two absorptive mechanisms. Several practical implications derive from this thesis. First, firms can apply the synthesized model as a kind of ‘blueprint’ providing orientation for how to combine competitive advantages. Second, policy makers can apply the outcomes as principles steering firms or industries to ‘higher’ levels of performance. Last, firm managers can adapt their own as well as their firm’s behaviour accordingly

Pathways to Industrialization and Regional Development

The world has seen a shift in socio-economic relations, in the patterns and processes of industrialization and regional development. The social regulation of the economic order, flexible production organization and industrial district formation have brought periods, places and pathways to the heart of economic debate. Pathways to Industrialization and Regional Development provides a platform from which to address a new economic order. All the major schools of thought are represented. Focussing upon the interactions between economic logic and political institutions at both the local and global levels, the authors set the agenda for the 1990s

Management. A continuing bibliography with indexes

This bibliography cites 604 reports, articles, and other documents introduced into the NASA scientific and technical information system in 1979 covering the management of research and development, contracts, production, logistics, personnel, safety, reliability and quality control. Program, project, and systems management; management policy, philosophy, tools, and techniques; decision making processes for managers; technology assessment; management of urban problems; and information for managers on Federal resources, expenditures, financing, and budgeting are also covered. Abstracts are provided as well as subject, personal author, and corporate source indexes

Pathways to Industrialization and Regional Development

The world has seen a shift in socio-economic relations, in the patterns and processes of industrialization and regional development. The social regulation of the economic order, flexible production organization and industrial district formation have brought periods, places and pathways to the heart of economic debate. Pathways to Industrialization and Regional Development provides a platform from which to address a new economic order. All the major schools of thought are represented. Focussing upon the interactions between economic logic and political institutions at both the local and global levels, the authors set the agenda for the 1990s

Organizational Resource Assembly in Technology Ventures

This dissertation addresses the assembly of organizational resources by technology ventures. We study how innovative firms acquire human and financial capital and then organize those resources, and how public policy affects that capability. In the first chapter, we study the role of information in organizational decision-making for the financing of entrepreneurial ventures. We formally model a decentralized set of agents who vote strategically to allocate resources to a project with unknown outcome; they can each acquire costly information to improve their decision quality. We test our predictions in the setting of venture capital, where partners make their own angel investments outside of their employer. We find that the venture capital partners, acting independently, make riskier investments into younger firms with less educated and younger founding teams, but these investments perform better on some metrics even when controlling for investment size and stage. Geographic distance and liquidity constraints increase the probability the investment is taken up by a partner and not the VC. In the second chapter, we evaluate the impact of skilled immigration on U.S. innovation by exploiting a random lottery in the H-1B visa program. Proponents argue that immigration allows firms to access technical skills and promote innovation, while opponents argue that firms substitute domestic labor for cheaper but equally or less skilled foreign labor. We find that winning an H-1B immigrant does not significantly increase patent applications or grants at the firm level, and there is pervasive use of the program in industries where patenting is not the main value-appropriation strategy. In the third chapter, we study how a firm should organize the diversity of technical experience, contained within its pool of inventive human capital, for firm-level innovation. Using a sample of biotechnology start-ups, we examine the implications of alternate firm-level design regimes, drawing on both a firm-year panel structure and an inventor-year difference-in-differences empirical approach. Organizing a firm\u27s human capital with greater across-team diversity yields increased firm-level innovation benefits as compared to organizing with greater within-team diversity. The benefits of across-team diversity stem mainly from the influence of that regime on team stability

Building Future Security: Strategies for Restructuring the Defense Technology and Industrial Base

This report elaborates on the findings of the earlier OTA publications and examines in greater detail the specific policy choices involved in restructuring the defense technology and industrial base (DTIB) over the next decade

Managing a changing health care environment: aligning hospital processes to the nature of care

CONTEXT Hospitals worldwide face challenging times and are consistently under pressure to control costs and improve quality of care. Research into improving health care should deal with seeking and defining the best methods of organizing and delivering services. In health care, there are two types care processes: sequential (the process is an orderly sequence of steps) and iterative (being composed of multiple cycles of hypothesis propositions and testing, where each cycle builds upon previous ones). These are very different, but both types could benefit if their organization were aligned with a tailored configuration of the operating system adjusted to the specific characteristics of both types of processes. The main purpose of this dissertation is to assess how the design of the operating system impacts efficiency in hospitals. In this dissertation we focus specifically on the sequential care process. METHODS The first part (chapter 2), presents a systematic literature review of the effects of specialized hospitals considering these as focused factories. In the second part (chapter 3), an exploratory database analysis of four hospitals was performed. We investigated whether hospital care processes can be assigned to different groups, resulting in better alignment of type and organization of care. In the third part, an empirical study of how the design of the operating system impacts efficiency in hospitals was conducted. Firstly (chapter 4), a multilevel analysis was performed to distinguish factors that influence flow efficiency in a standardized process (i.e. the cataract surgery process), focusing on the role of the organizations, physicians, and case-mix variables of patients. Secondly (chapter 5), a comparative benchmark study with a mixed-method design was conducted to compare sequential care processes between hospitals. We examined how the cataract surgery process operates in hospitals and which design of the operating system is preferable. RESULTS Considering the effects of specialized facilities as a strategy for standalone facilities that excel, we found no compelling evidence demonstrating the added value of these specialized facilities in terms of quality or cost. In addition, their corresponding impact on full-service general hospitals remains unclear. There are groups of patients with inherently different degrees of variation in length-of-stay due to illness and treatment patterns. However, there are significant differences in the distribution of variation groups between the hospitals suggesting that there are clear process differences which led us towards further investigation of the sequential hospital care processes in this dissertation Investigating a sequential care process (i.e. the cataract surgery) in hospitals, we found (1) controllable and uncontrollable factors influencing flow efficiency and (2) that treating sequential care processes in an operating setting specifically dedicated to such processes enhanced flow- and resource efficiency. In these settings, we not only found higher capacity use, but also shorter turnover times and significantly lower staffing levels, without affecting efficiency and resulting in lower costs. DISCUSSION The importance of differentiating distinct processes for health care problem-solving lies in the added value of different approaches to their design and management. Thus, different services and processes require different operating systems. Our results demonstrate that aligning structure and process components with the design of the operating system positively influences operational performance. The sequential care process (e.g., cataract surgery) is designed in line with a standardized process; however, differences in the design of the operating system between the hospitals illustrate the impact on operational performance. We must emphasize the importance of differentiating the types of variation and noting the presence of, as the goal must be to eliminate the unwarranted “artificial” special-cause variation and manage warranted, common-cause variation. This dissertation provides practitioners and academics with a fresh perspective on the practices of sequential care processes and the factors limiting them. It also serves as a foundation for future initiatives aimed at improving operational performance in hospitals