Main benefits obtained from a successful JIT implementation Alcaraz, Jorge L. García; Macías, Aidé A. Maldonado; Luevano, Diana Jazmín Prieto ...
International journal of advanced manufacturing technology,
10/2016, Letnik:
86, Številka:
9-12
Journal Article
Recenzirano
Literature has reported 31 benefits obtained by companies after a successful JIT implementation. However, this research reduces the list by means of a data reduction technique to identify those ...essential benefits that must be pursued. The 31 benefits are integrated in a questionnaire that is administered to 144 production managers in maquiladoras in Mexico to measure the extent to which they are obtained according to respondents. One the one hand, a validation process and descriptive analysis are carried out for every benefit by considering their median values as a measure of central tendency and interquartile range values as a measure of dispersion. On the other hand, data reduction was achieved by means of a factor analysis based on principal components and varimax rotation. Four main factors related to JIT benefits are identified after the factor analysis, which explain 67.27 % of total variance of data. Identified factors concern inventory management, production process, human resources, and economic benefits.
Virtual machine warmup blows hot and cold Barrett, Edd; Bolz-Tereick, Carl Friedrich; Killick, Rebecca ...
Proceedings of ACM on programming languages,
10/2017, Letnik:
1, Številka:
OOPSLA
Journal Article
Recenzirano
Odprti dostop
Virtual Machines (VMs) with Just-In-Time (JIT) compilers are traditionally thought to execute programs in two phases: the initial warmup phase determines which parts of a program would most benefit ...from dynamic compilation, before JIT compiling those parts into machine code; subsequently the program is said to be at a steady state of peak performance. Measurement methodologies almost always discard data collected during the warmup phase such that reported measurements focus entirely on peak performance. We introduce a fully automated statistical approach, based on changepoint analysis, which allows us to determine if a program has reached a steady state and, if so, whether that represents peak performance or not. Using this, we show that even when run in the most controlled of circumstances, small, deterministic, widely studied microbenchmarks often fail to reach a steady state of peak performance on a variety of common VMs. Repeating our experiment on 3 different machines, we found that at most 43.5% of <VM, Benchmark> pairs consistently reach a steady state of peak performance.
Given the successful implementation of Lean Management (LM) in other service industries and its potential benefits for hospitality, this study aims to pursue two specific goals: 1) to offer an ...overview of LM research in the hospitality industry; 2) to detect and propose LM research lines in this sector. The research methodology chosen for these goals is a systematic literature review based on a structured, transparent, replicable multistage process. Thirty-six references have been found, which indicates the paucity of research studies in this field. The use of LM tools in hotels seems to be very limited, with VSM and the 5S applications standing out. Reference analysis clearly shows that much more research is required on specific applications in many hotel activities and some under-reported practices.
•Research in the field of LM in hotels is still scarce, although growing.•The use of LM tools in hotels seems to be limited, however, VSM and 5S stand out.•More research studies are needed on LM practices in a variety of hotel activities.•Hotels can/should benefit from LM to increase competitiveness and customer value.
Design of a Database-Driven Model Error Compensator Yoshida, Syota; Wakitani, Shin
Transactions of the Institute of Systems, Control and Information Engineers,
2024/03/15, Letnik:
37, Številka:
3
Journal Article
Odprti dostop
A model error compensator (MEC) was proposed as a method to improve the control loop performance by suppressing modeling errors. MEC suppresses modeling errors by providing feedback on the error ...between control output and model output. In MEC, the performance of the modeling error suppression is strongly affected by the structure of the compensator and the tuning of control gains. Model-based design methods based on robust control and parameter tuning methods based on data-driven approaches have been proposed as design methods for MEC. However, an appropriate compensator structure and parameters are required to suppress modeling errors effectively. This study proposes a design method for structure-free MEC to directly determine compensation inputs using a database-driven approach. Thanks to the proposed method, the optimal output from the compensator can be obtained using only data. This paper verifies the effectiveness through numerical examples and implementation to the hydraulic motor control system.
Recent research on Agile Manufacturing (AM) has examined its relationship with Total Quality Management (TQM), Just in Time (JIT), and different levels of firm performance. Mixed results have been ...reported, probably due to non-availability of well validated AM constructs. This research develops a 3-stage model and examines AM's direct and/or indirect relationship with common infrastructures, TQM, and JIT and its effects on different levels of firm performance in the context of the Pakistani industrial sectors, specifically the apparel export industry. Data is collected from 248 Pakistani apparel export firms and the model is estimated using structural equation modelling. The results indicate that common (internal) infrastructure and TQM has a positive relationship with AM specifically in the apparel export firms in a third world economy where the industrial sector is in a nascent state. Whereas, JIT relationship is positively mediated through external infrastructure, TQM and JIT did not seem to contribute directly in operational performance. However, this relationship is significant when it is mediated through AM. Market performance positively mediates the relationship between operational performance and financial performance of the firm. The implications of the findings for researchers and practitioners, looking at the industrial sectors in the developing world, are discussed and research directions offered.
We study the problem of two-machine no-wait flowshop scheduling with learning effect and convex resource-dependent processing times. Under the condition of the due-date assignment with common flow ...allowance (i.e. slack (SLK) due-date assignment), we provide a bi-criteria analysis where the first criterion is to minimise the scheduling criteria (i.e. the weighted sum of earliness, tardiness and flow allowance costs), and the second criterion is to minimise the resource consumption cost (i.e. the weighted sum of resource consumption cost). The objective is to determine the optimal job sequence, resource allocations and common (flow allowance) slack time that minimise the three different versions of the two criteria. We prove that these problems can be solved in polynomial time.
Purpose
– The purpose of this paper is to review the existing literature on empirical research in lean manufacturing (LM). It provides a critical assessment of empirical research methodology of 178 ...research articles published from 1990 to 2009.
Design/methodology/approach
– The article reviewed a set of 178 empirical research articles in LM research with respect to empirical research design and its related facets. The 236 empirical research articles which are published in 70 journals during 1990-2009 are collected from four major management science publishers, namely, Emerald Online, Science Direct, Springer Link and Taylor & Francis. In total 178 research articles published in 24 journals are selected for critical review of empirical research methodology in LM. The approach for the critical review of 178 empirical research articles in LM is based on empirical research approach given by Flynn et al. (1990). The critical review discusses the current status of empirical research in LM and future directions.
Findings
– It is concluded from the analysis of the results that: the number of empirical research articles in LM is increasing at a faster pace than ever before; theory building and theory verification articles are equally advanced; the researchers have also unexplored various aspects of empirical research such as importance of triangulation of data, alternate research designs other than survey and case studies; contextual focus is mostly on the manufacturing industry; more focus required on other aspects of empirical research such as collecting the samples from developing and undeveloped countries, larger sample size, longitudinal data collection methods. Finally, it concludes that there is a need of LM frameworks, which gives the stepwise process to remove all kinds of wastes from any organization.
Originality/value
– To the knowledge of the authors, it is the first of its kind attempt to critically review the empirical research articles in LM. The review analysis entirely focussed on descriptive statistics of empirical research in LM. The sample size is one of the unique features of this research as the number of shortlisted articles is 178 in 24 journals published over a time span of 20 years (1990-2009).
Low-Level Virtual Machine (LLVM) compiler infrastructure is a useful tool for building just-in-time (JIT) compilers, besides its reliable front end represented by a clang compiler and its elaborated ...middle end containing different optimizations that improve the runtime performance. This paper specifically addresses the part of building a JIT compiler using an LLVM with the scope of obtaining the hardware architecture details of the underlying machine such as the number of cores and the number of logical cores per processing unit and providing them to the NUMA-BTLP static thread classification algorithm and to the NUMA-BTDM static thread mapping algorithm. Afterwards, the hardware-aware algorithms are run using the JIT compiler within an optimization pass. The JIT compiler in this paper is designed to run on a parallel C/C++ application (which creates threads using Pthreads), before the first time the application is executed on a machine. To achieve this, the JIT compiler takes the native code of the application, obtains the corresponding LLVM IR (Intermediate Representation) for the native code and executes the hardware-aware thread classification and the thread mapping algorithms on the IR. The NUMA-Balanced Task and Loop Parallelism (NUMA-BTLP) and NUMA-Balanced Thread and Data Mapping (NUMA-BTDM) are expected to optimize the energy consumption by up to 15% on the NUMA systems.
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