• Proceedings of the Korea Port Economic Association Conference
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• 2006.08a
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• pp.159-179
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• 2006

As the current trend to the main index of the port competitiveness evaluation, the competitiveness index of the port service comes to more important than the part of expense, location and facility. To reform the bottleneck of port has an effect on improving port service competitiveness. Therefore, this study shows the importance of analyzing bottlenecks on logistics to improve port competitiveness. It collected recent questionnaire data which are the subject as the Custom Service, the Chamber of Commerce and Industry, the Trade Association about bottlenecks of port logistics for working out bottlenecks of domestic port logistics and it produced the order of priorities of bottlenecks by multiplying each output priorities and weights of each process in user of Incheon inner-outer port which is focused on container freight by analysis of priority and Analytic Hierarchy Process(AHP). Unlike existing studies, this study has important values. It presents the priority evaluation only focused on the container freight was produced by port users who are categorized into shipping company, terminal operation company and forwarder, car-ferry in Incheon inner-outer port and making a application of logistics process. It means internal and external competitiveness improvement plan can be presented more concretely and detailed than past competitiveness attributes such as location, facility, service and expense. If the analysis of port logistics bottlenecks which was focused on container freight is extended to the part of general cargo and sundries such as haul grain, car, scrap iron, those studies will be able to provide Incheon port users with useful information and a model of analyzing overall bottleneck of logistics in Incheon port.

• International Journal of Aerospace System Engineering
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• v.1 no.1
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• pp.44-47
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• 2014

This study proposes a development for the nano silver adhesive, which is applicable to high efficiency LED(light-emitting diode) light. The important issue of LED light is heat exhaust from LED. Generally, the middle area of LED light is increased up to 380K. Therefore, the bottleneck between LED chip and heat sink are caused by high temperature. In this work, the adhesive material between LED Chip and heat sink was newly developed for improvement of bottleneck. The nano silver was adopted to solve heat problem of chip on board package for LED light. In order to evaluate the performance of the nano silver adhesive, the thermal analysis was performed. Moreover both adhesive performance and heat exhaust were verified through the prototype test. From the experimental test results, it is found that the developed nano silver adhesive has the high performance.

• Journal of Computing Science and Engineering
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• v.10 no.4
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• pp.128-136
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• 2016

It is impossible for any human being to analyze the more than 500 million tweets that are generated per day. Lexical ambiguities on Twitter make it difficult to retrieve the desired data and relevant topics. Most of the solutions for the word sense disambiguation problem rely on knowledge base systems. Unfortunately, it is expensive and time-consuming to manually create a knowledge base system, resulting in a knowledge acquisition bottleneck. To solve the knowledge-acquisition bottleneck, a topic signature is used to disambiguate words. In this paper, we evaluate the effectiveness of various features of newspapers on the topic signature extraction for word sense discrimination in tweets. Based on our results, topic signatures obtained from a snippet feature exhibit higher accuracy in discriminating company names than those from the article body. We conclude that topic signatures extracted from news articles improve the accuracy of word sense discrimination in the automated analysis of tweets.

• The Korean Journal of Applied Statistics
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• v.17 no.2
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• pp.311-326
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• 2004

We propose a Markov model of two bottleneck ECN/RED gateways experiencing a large number of TCP users. We show that, as the number of users becomes large, the queue sizes per user of the both gateways converge at steady-state to individual fixed points. Also, we derive a computational algorithm to exactly obtain the fixed points and present simulation example showing the limiting behavior of the gateway traffic.

• Proceedings of the Korea Society for Simulation Conference
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• 1999.04a
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• pp.105-109
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• 1999

Tool shop of the D Heavy Industries Co.(DHI) fabricates engines for a bus, truck, small ship. In order to increase the production capacity of engines, DHI will be established the new tool shop that consists of a block line, head line, assembly line, test line and AS/RS in 1999. In order to assure the production capacity designed of the new tool shop for producing engines and improve the production process of it, it is needed to find a bottleneck process and an optimal way of allocating workloads among machines and workers to maximize the production. In a way to solve this, we model the engine fabrication process of the tool shop and analyze its performance by computer simulation. In this study, we at first identify the bottleneck processes of the engine fabrication process under the designed operation policy. Then, we derive some alternative operating policies applicable to the new tool shop of an engine, and analyze the optimal operation policy by comparing the performance of the tool shop following each alternative policy.

• Journal of the Korea Computer Industry Society
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• v.9 no.2
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• pp.63-68
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• 2008

The purpose of a parallel scheduling is to carry out the scheduling with the minimum synchronization overhead and bottleneck under a multiprocessor environment and to perform load balance for a parallel iteration. In this paper, analyse the conventional parallel scheduling methods and drive the problems from each method in order to achive the minimum scheduling overhead and load balance. These problems will go far toward solving the design of effective algorithm.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.5_6
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• pp.299-306
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• 2003

This paper formulates a problem of embedded real-time system re-engineering, and presents its solution approach. Embedded system re-engineering is defined as a development task of meeting performance requirements newly imposed on a system after its hardware and software have been fully implemented. The performance requirements nay include a real-time throughput and an input-to-output latency. The proposed solution approach is based on a bottleneck analysis and nonlinear optimization. The inputs to the approach include a system design specified with a process network and a set of task graphs, task allocation and scheduling, and a new real-time throughput requirement specified as a system's period constraint. The solution approach works in two steps. In the first step, it determines bottleneck precesses in the process network via estimation of process latencies. In the second step, it derives a system of constraints with performance scaling factors of processing elements being variables. It then solves the constraints for the performance staling factors with an objective of minimizing the total hardware cost of the resultant system. These scaling factors suggest the minimal cost hardware upgrade to meet the new performance requirement. Since this approach does not modify carefully designed software structures, it helps reduce the re-engineering cycle.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.227-233
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• 2001

Four polymorphic allozymes were used for genetic analysis of overwintering populations of field diamondback moth, Plutella xylostella (Linne). Different allele frequencies were found among three local populations of Andong, Youngchon, and Yangsan in all loci. Two allozyme loci (acid phosphatase and phosphoglucomutase) showed significant deviation from Hardy-Weinberg equilibrium in allele frequencies among these populations. Estimated Nei's genetic distance varied from 0.0151 between Yangsan and Youngchon to 0.0877 between Andong and Youngchon. Compared with the previous genetic distances in this moth, a little higher genetic differentiation among these overwintering populations suggests that there would be a specific genetic bottleneck in each local population during overwintering period.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.7
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• pp.51-58
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• 2010

Wireless Mesh Network has drawn much attention due to wide area service coverage with low system cost. However, there is a bottleneck problem in wireless mesh network since the traffic is aggregated into a gateway. Placement of multi-radio can easy the bottleneck problem, but without careful design it results in unnecessary system cost increasement. In this paper, we propose a system cost minimization through differential antenna placement where optimum antenna placement is determined by the required wireless link capacity. With CPLEX program, optimum number of antennae is determined as a function of local user traffic and gateway capacity. From numerical analysis, it is confirmed that our proposed model can solve bottleneck problem, and at the same time save the system cost.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.1
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• pp.111-116
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• 2019

Recently, GPU expands application domains from graphic processing to various kinds of parallel workloads. However, current GPU systems focus on the maximization of each workload's parallelism through simplified control rather than considering various workload characteristics. This paper classifies the resource usage characteristics of GPU workloads into computing-bound, memory-bound, and dependency-latency-bound, and quantifies the fine-grained bottleneck for efficient workload allocation. For example, we identify the exact bottleneck resources such as single function unit, double function unit, or special function unit even for the same computing-bound workloads. Our analysis implies that workloads can be allocated together if fine-grained bottleneck resources are different even for the same computing-bound workloads, which can eventually contribute to efficient workload allocation in GPU.