• 한국정보과학회논문지:소프트웨어및응용
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• 제31권10호
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• pp.1364-1373
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• 2004

진화 하드웨어(Evolvable Hardware)는 환경에 적응하여 스스로 구성을 변경할 수 있는 하드웨어로 생산성 향상 및 독창적 회로설계를 위해 최근 널리 연구되고 있다 하지만, 하드웨어의 복잡도가 증가할수록 진화를 위해 탐색해야 하는 해공간의 크기가 기하급수적으로 증가하기 때문에 아직까지 복잡한 하드웨어에 대해서는 좋은 활용방안을 찾지 못하고 있다. 이 논문에서는 좀더 효율적인 설계를 위하여 복잡한 하드웨어를 모듈별로 나누어 진화시키는 방법을 제시한다. 몇 가지 회로를 기존 회로 진화 설계방식과 제시하는 모듈진화 방식으로 실험하여 비교한 결과 약 50배에서 1,000배까지의 세대절약 효과를 얻을 수 있었으며, 좀더 최적화된 하드웨어를 얻을 수 있었다.

• International Journal of Aeronautical and Space Sciences
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• 제9권2호
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• pp.121-128
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• 2008

Modularized GPS software defined radio (SDR) has many advantages of applying and modifying algorithm. Hardware based GPS receiver uses many hardware parts (such as RF front, correlators, CPU and other peripherals) that process tracked signal and navigation data to calculate user position, while SDR uses software modules, which run on general purpose CPU platform or embedded DSP. SDR does not have to change hardware part and is not limited by hardware capability when new processing algorithm is applied. The weakness of SDR is that software correlation takes lots of processing time. However, in these days the evolution of processing power of MPU and DSP leads the competitiveness of SDR against the hardware GPS receiver. This paper shows a study of modulization of GPS software platform and it presents development of the GNSS software platform using MATLAB Simulink™. We focus on post processing SDR platform which is usually adapted in research area. The main functions of SDR are GPS signal acquisition, signal tracking, decoding navigation data and calculating stand alone user position from stored data that was down converted and sampled intermediate frequency (IF) data. Each module of SDR platform is categorized by function for applicability for applying for other frequency and GPS signal easily. The developed software platform is tested using stored data which is down-converted and sampled IF data file. The test results present that the software platform calculates user position properly.

• 한국산학기술학회논문지
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• 제13권12호
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• pp.5704-5708
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• 2012

본 논문에서는 DEA(Differential Evolution Algorithm)기법을 이용하여 트래버스 연삭의 최적 조건을 선정하기 위한 알고리즘을 제안하였다. 최적 연삭 조건 선정을 위한 가격함수는 가공 경비, 생산율 및 표면 거칠기 등의 다중 함수식을 이용하였다. 또한 연삭 조건에 대한 구속 조건으로 열 손상 효과, 가공 툴의 강성, 연삭 휠 마모 상수 및 표면 거칠기 등을 고려하였다. 알고리즘의 구현은 산업현장에서 널리 사용되는 LabView소프트웨어를 사용하였다. 제안된 알고리즘의 성능은 컴퓨터 시뮬레이션을 통해 GA알고리즘의 결과와 비교하여 검증하였다.

• 한국산학기술학회논문지
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• 제14권1호
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• pp.7-12
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• 2013

본 논문은 연삭 공정의 최적화 알고리즘과 이를 구현하기 위한 방안을 제안하였다. 최적의 연삭 공정 설계를 위해서 최적화 함수를 제안하고 선정된 최적 함수의 해를 구하기 위해 DE(Differential Evolution)알고리즘을 이용하였다. 알고리즘의 구현은 산업현장에서 널리 사용되고 있는 LabView소프트웨어를 통해 구현하였고 컴퓨터 시뮬레이션을 통해 제안된 알고리즘을 검증하였다. 본 논문에서 획득한 최적화 기법은 연삭공정의 가이드라인으로 활용 될 수 있을 것으로 사료된다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.474-479
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• 2005

Experimental and theoretical studies of internal cavity pressure during injection molding of a spiral tube cavity were carried out. The frozen layer thickness and the evolution of internal cavity pressure were calculated using a commercial software (C-MOLD). The evolution of the internal cavity pressure was recorded during injection molding of polystyrene into a spiral tube mold. To explain the differences observed between the calculated and measured internal cavity pressure, a pressure correction factor (PCF) was introduced based on the plane stress theory. This factor was determined by analyzing the stress state in the melt and calculating the frozen layer thickness near the mold wall. The corrected and experimental pressures have been compared to validate the applicability of the pressure correction factor.

• Journal of Computing Science and Engineering
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• 제9권4호
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• pp.190-203
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• 2015

Free and open source software (FOSS) has created a large pool of source codes that can be easily copied to create new applications. However, a copy should preserve copyright notice and license of the original file unless the license explicitly permits such a change. Through software evolution, it is challenging to keep original licenses or choose proper licenses. As a result, there are many potential license violations. Despite the fact that violations can have high impact on protecting copyright, identification of violations is highly complex. It relies on manual inspections by experts. However, such inspection cannot be scaled up with open source software released daily worldwide. To make this process scalable, we propose the following two methods: use machine-based algorithms to narrow down the potential violations; and guide non-experts to manually inspect violations. Using the first method, we found 219 projects (76.6%) with potential violations. Using the second method, we show that the accuracy of crowds is comparable to that of experts. Our techniques might help developers identify potential violations, understand the causes, and resolve these violations.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2005년도 e-Biz World Conference 2005
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• pp.215-220
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• 2005

For widespread adoption for the RFID technology, RFID middleware is considered as the key enabler of the RFID evolution while it manages the flow of data between tag readers and enterprise applications and is responsible for the quality, and therefore usability, of the information. In this paper, we introduce the recent researches and developments of RFID middleware and explain the software framework of the RFID middleware which is currently developed in ETRI. In conclusion, our experiences with the current implementation are presented

• Journal of information and communication convergence engineering
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• 제1권3호
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• pp.99-103
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• 2003

Classes are apt to include useless codes and inadequate inheritance relationship between them when they are being updated, inserted and deleted during the evolution process of object-oriented software, leading to lots of errors. Conventional class restructuring methods degrade the effectiveness of reusability since they go with preprocesses such as dependency analysis and estimation of class cohesion and run statically. In this paper, we propose a new C＋＋ class-restructuring algorithm that does not require those preprocesses and runs dynamically by improving ART learning algorithm in the artificial neural networks.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제9권2호
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• pp.83-89
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• 2005

In this paper a new algorithm of learning and evolving artificial neural networks using gene expression programming (GEP) is presented. Compared with other traditional algorithms, this new algorithm has more advantages in self-learning and self-organizing, and can find optimal solutions of artificial neural networks more efficiently and elegantly. Simulation experiments show that the algorithm of evolving weights or thresholds can easily find the perfect architecture of artificial neural networks, and obviously improves previous traditional evolving methods of artificial neural networks because the GEP algorithm imitates the evolution of the natural neural system of biology according to genotype schemes of biology to crossover and mutate the genes or chromosomes to generate the next generation, and the optimal architecture of artificial neural networks with evolved weights or thresholds is finally achieved.

• 전자통신동향분석
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• 제4권1호
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• pp.35-43
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• 1989

The evolution of telecommunications has raised the profile of many segments of the network that were not previously considered important. Until recently, basic telephony existed with the extension of passive cables without any particular user network interface. In the area of data communications, the introduction of flexible packet switching has allowed the network to evolve in a far more efficient manner. To overcome such separated network problems and business needs of both users and network providers, the integrated narrowband ISDN concept is being developed in most countries for implementation in the public switched telephone network (PSTN). The targets of ISDN, in my opinion, can be explained as follows : To the user, ISDN should provide the services at any time, at any place, through any media. To the business customer using PABX or LAN applications, ISDN should introduce customized services rapidly and also, ISDN should be developed by the modular hardware and software design approach in order for new services to be introduced rapidly and effectively. Software can be also developed by non-expert local staff to cater for adopting new user's service requirements immediately. Finally, ISDN will be able to increase business chances and benefit both users and operating companies.