• Journal of Korean Society for Quality Management
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• v.39 no.2
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• pp.271-280
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• 2011

In this paper, the relationships between code-share networks and performances in airline industry were analyzed by using Social Network Analysis (SNA). We first analyzed the schedule data from OAG (Official Airline Guide) to obtain core-share information of airline industries. SNA was, then, applied to the code-share information. Finally, statistical analysis was conducted to analyze the relationships between code-share social networks and performances. The result shows that the size and out-degree centrality have relatively significant effects on the performance of airline industries, while in-degree and betweenness centrality has less significant effects.

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.07a
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• pp.23-24
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• 2015

소프트웨어 프로젝트에서 발생하는 버그의 수가 증가함에 따라 이를 수정할 적합한 개발자를 효과적으로 찾기 위한 연구들이 진행되었다. 하지만, 대부분의 연구들이 텍스트 기반의 라인 변경을 통해 얻은 정보만을 활용하기 때문에 정확도가 떨어지며, 파일, 클래스, 함수와 같은 다양한 계층 단위에 대한 처리가 어렵다. 본 논문은 개발자의 코드 변경 정보를 추적함으로써 기여도를 보다 정확하게 계산하고, 다양한 코드 수준에서의 분석을 효과적으로 지원하는 AST기반의 지분 계산 접근법을 제안한다.

• Asia-Pacific Journal of Business
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• v.12 no.3
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• pp.329-342
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• 2021

Purpose - The purpose of this study is to analyze the effect of investment by the National Pension Service, which has a high share as a single fund, on the dividend payout ratio. Design/methodology/approach - This study secured a share through DART of the Financial Supervisory Service and disclosure of the National Pension Service. We also used a fixed-effects model and 2SLS to analyze the data. Findings - First, it was found that there was a possibility of conflicting interests among shareholders concerning the company's dividend payment policy. Second, in the range of 3% to 4.9% of the National Pension Service shareholding, an additional increase in the holding ratio was found to have a positive (+) effect on the dividend rate. Third, after the introduction of the Stewardship Code, it was found that the increase in ownership of the fund had a positive (+) effect on the company's dividend payout ratio, regardless of the share ratio range. Moreover, the relationship between the fund ownership and the dividend payout ratio showed a clear positive relationship when free cash flow was high along investment opportunities were low. Research implications or Originality - First, This study included less than 5% of the share in the analysis. Second, We used the recent changes in fund shareholder activities. Third, We tested an instrumental variable to confirm the relationship between the National Pension Service share and the dividend ratio.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.3A
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• pp.277-285
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• 2008

We previously proposed an Orthogonal Code Hopping Multiplexing (OCHM) scheme for statistical multiplexing on a synchronous downlink. OCHM enables a large number of users to share a limited number of code channels through statistical multiplexing. We here improve the performance of OCHM by prioritizing encoded symbols according to their importance using both the conventional code division and the previously proposed code hopping multiplexing schemes. Prioritization is useful for channel coding schemes with different levels of importance for encoded symbols such as turbo-codes. Scheme performance is evaluated by simulation in terms of the required Eb/N0 for a 1% block error rate.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.5
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• pp.1035-1040
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• 2009

We propose a new encoder/decoders based on an tune able wavelength converter(TWC) and an arrayed waveguide grating(AWG) router for large capacity optical CDMA networks. The proposed encoder/decoder treats codewords of wavelength/time 2-D code simultaneously using the dynamic code allocation property of the TWC and the cyclic property of the AWG router, and multiple subscribers can share the encoder/decoder in networks. Feasibility of the structure of the proposed encoder/decoder for dynamic code allocation is tested through simulations using two wavelength/time 2-D codes, which are the generalized multi-wavelength prime code(GMWPC) and the generalized multi-wavelength Reed-Solomon code(GMWRSC). Test results show that the proposed encoder/decoder can increase the channel efficiency not only by increasing the number of simultaneous users without any multiple-access interference but by using a relatively short length CDMA codes.

• Journal of computational fluids engineering
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• v.21 no.3
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• pp.89-97
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• 2016

In this study, direct code coupling, in which two codes share a single flow field, was conducted using 3-dimensional high resolution thermal hydraulics code, CUPID and 1-dimensional system analysis code, MARS. This approach provide the merit to use versatile capability of MARS for nuclear power plants and 3-dimensional T/H analysis capability of CUPID. Numerical Method to directly couple CUPID and MARS was described in this paper. The straight flow and manometer flow oscillation were calculated to verify conservation of coupled CUPID/MARS code in mass, momentum, and energy. This verification calculations indicates that the CUPID/MARS is coupled appropriately in numerical aspect and the coupled code can be applied to nuclear reactor thermal hydraulics after validation against integral transient experiments.

• Journal of Korean Society of Disaster and Security
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• v.6 no.3
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• pp.29-34
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• 2013

This study is to provide the implementation plan for standard code to efficiently manage curriculum information in disaster and safety education programs across domestic and foreign institutions, and to encourage active information sharing. Projects regarding disaster safety education have been progressed and developed since the opening of NDMI on March 2006. Efficient management and systematic operation for the existing disaster safety education contents are also required. It is essential for both domestic and foreign disaster management organizations to share and utilize their educational contents each other prior to the effect of the Framework Act on the Management of Disaster and Safety starting from February 7th, 2014. As disaster gets more complex and diverse in its types and sizes, the share of information on advanced disaster and safety education system between each countries is becoming more necessary than they ever did before. Therefore, the standard code of disaster safety education curriculum is resulted based on the flexibility that accommodates the change of education environment and extended applications in both domestic and foreign education institutions. The effective application of standard code will be a possible way to improve the disaster safety education system and help to set its correct definition.

• Journal of the Korean Mathematical Society
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• v.58 no.1
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• pp.29-44
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• 2021

The set D of column vectors of a generator matrix of a linear code is called a defining set of the linear code. In this paper we consider the problem of constructing few-weight (mainly two- or three-weight) linear codes from defining sets. It can be easily seen that we obtain an one-weight code when we take a defining set to be the nonzero codewords of a linear code. Therefore we have to choose a defining set from a non-linear code to obtain two- or three-weight codes, and we face the problem that the constructed code contains many weights. To overcome this difficulty, we employ the linear codes of the following form: Let D be a subset of ��2n, and W (resp. V ) be a subspace of ��2 (resp. ��2n). We define the linear code ��D(W; V ) with defining set D and restricted to W, V by $${\mathcal{C}}_D(W;V )=\{(s+u{\cdot}x)_{x{\in}D^{\ast}}|s{\in}W,u{\in}V\}$$. We obtain two- or three-weight codes by taking D to be a Vasil'ev code of length n = 2m - 1(m ≥ 3) and a suitable choices of W. We do the same job for D being the complement of a Vasil'ev code. The constructed few-weight codes share some nice properties. Some of them are optimal in the sense that they attain either the Griesmer bound or the Grey-Rankin bound. Most of them are minimal codes which, in turn, have an application in secret sharing schemes. Finally we obtain an infinite family of minimal codes for which the sufficient condition of Ashikhmin and Barg does not hold.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.5A
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• pp.359-369
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• 2005

For large capacity optical CDMA networks, we propose a shared-type encoder/decoders based on an tunable wavelength converter(TWC) and an arrayed waveguide grating (AWG) router. The proposed encoder/decoder treats codewords of wavelength/time 2-D code simultaneously using the dynamic code allocation property of the TWC and the cyclic property of the AWG router, and multiple subscribers can share the encoder/decoder in networks. Feasibility of the structure of the proposed encoder/decoder for dynamic code allocation is tested through simulations using two wavelength/time 2-D codes, which are the generalized multi-wavelength prime code(GMWPC) and the generalized multi-wavelength Reed-Solomon code(GMWRSC). Test results show that the proposed encoder/decoder can increase the channel efficiency not only by increasing the number of simultaneous users without any multiple-access interference but by using a relatively short length CDMA codes.

• International Journal of Computer Science & Network Security
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• v.23 no.8
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• pp.77-84
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• 2023

The utilization of GPUs on general-purpose computers is currently on the rise due to the increase in its programmability and performance requirements. The utility of tools like NVIDIA's CUDA have been designed to allow programmers to code algorithms by using C-like language for the execution process on the graphics processing units GPU. Unfortunately, many of the performance and correctness bugs will happen on parallel programs. The CUDA tool support for the parallel programs has not yet been actualized. The use of a dynamic analyzer to find performance and correctness bugs in CUDA programs facilitates the execution of sophisticated processes, especially in modern computing requirements. Any race conditions bug it will impact of program correctness and the share memory bank conflicts to improve the overall performance. The technique instruments the programs in a way that promotes accessibility of the memory locations accessed by different threads well as to check for any bugs in the code of a program. The instrumented source code will be used initiated directly in the device emulation code of CUDA to send report for the user about all errors. The current degree of automation helps programmers solve subtle bugs in highly complex programs or programs that cannot be analyzed manually.