• 한국시뮬레이션학회논문지
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• 제3권1호
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• pp.107-114
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• 1994

This paper describes an integrated environment for logic circuit simultion which is an important step of logic circuit design. The system consists of a logic simulator kernel, an expandible element routine library. a functional level element routine generator, several HDL input parsers, and a postprocessor. The system can simulate the same system in several levels of hierarchy. The experimental result shows that the system is very efficient and useful for design of logic circuits.

• Journal of the Korean Data and Information Science Society
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• 제18권1호
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• pp.195-210
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• 2007

This paper develops a consistent nonparametric test for Granger causality in the context of strong-mixing process, which covers a large class of stationary processes including ARMA and ARCH models. The previously proposed tests require absolute regularity ($\beta$-mixing) more stringent than the strong-mixing condition. We prove the consistency of the test under a high level assumption on the approximation error of U statistic by its projection. Due to the sample splitting, the test statistic we propose is asymptotically normally distributed under the null.

• 한국정보보호학회:학술대회논문집
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• 한국정보보호학회 2001년도 종합학술발표회논문집
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• pp.111-114
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• 2001

시스템 침입을 위해서 사용할 수 있는 공격 기법은 그 종류가 매우 다양하다. 그러나 최종적인 시스템 침입의 목표는 버퍼오버플로우 공격을 통한 관리자 권한의 획득이다. 버퍼오버플로우 현상은 메모리 공간의 경계 영역에 대한 프로그래밍 언어 수준의 검사 도구를 제공하지 않는 C/C++ 의 언어적 특성으로 인해 발생한다. 본 논문에서는 리눅스 커널 수준에서 시스템 보안을 위한 참조 모니터를 제안하고 이를 이용하여 버퍼오버플로우 공격에 대응할 수 있는 보안 기법을 제시한다.

• 한국멀티미디어학회논문지
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• 제7권8호
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• pp.1058-1065
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• 2004

단순 모니터에서 CPU, 메모리, 그리고 하드디스크를 갖춘 셋탑박스에 이르기까지 내장형 시스템은 다양한 응용에 사용되고 있다. 특히 휴대용 또는 소형기기에 멀티미디어를 서비스하는 경우가 증가하고 있고 이들 시스템에는 내장형 운영체제가 탑재되고 있다. 본 논문에서는 멀티미디어 서비스를 위한 내장형 리눅스가 탑재된 임베디드 시스템에서 응용 프로그램과 운영체제 커널사이의 메모리 복사 요구를 감소시키는 Null copy기법을 제안한다. 저성능의 컴퓨팅 파워 및 저용량의 메모리를 가진 내장형 시스템에서 연속 미디어를 네트워크를 통해 실시간으로 전송하고자 할 때 Null copy 기법은 시스템의 QoS를 만족시킬 수 있다. 웹 카메라를 내장형 리눅스 개발 보드에 장착하여 영상 전송 환경을 구축한 결과 Null copy 기법은 CPU 이용률 및 마감시간 실패측면에서 기존 커널에 비해 우수한 성능을 나타내었다.

• 조명전기설비학회논문지
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• 제22권4호
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• pp.93-99
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• 2008

휴대용 기기의 다양한 기능으로 인해 에너지 절약은 더욱 중요한 문제가 되고 있다. Dynamic Voltage Scaling(DVS)는 임베디드 기기에서 대표적으로 사용되는 에너지 절약 방법이다. 본 논문에서는 응용프로그램의 작업량 변화에 따라 프로세서의 동작 전압과 속도를 조절할 수 있는 DVS 알고리즘을 제안한다. 제안된 DVS 알고리즘은 커널의 DVS 모듈과 응용프로기램의 작업량 변화를 관찰하는 함수로 구성되어 있으며 작업량이 급격히 증가 하거나 감소하는 경우 이에 알맞은 프로세서의 동작 수준을 결정함으로서 작업의 데드라인을 넘기지 않으면서도 전력 소비를 줄일 수 있도록 하였다. 제안된 DVS 알고리즘은 Linux 2.6 커널과 PXA270프로세서를 이용한 임베디드 시스템에서 구현되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권1호
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• pp.30-34
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• 2001

The expediency of promoting rabbit production on underutilized by-product feedstuffs prompted the current investigation of caecal fermentation pattern, blood biochemical profile and histopathological changes of vital organs in 48 broiler rabbits fed diets containing 0, 5, 10 and 20% level of neem seed kernal cake (NSKC) for 6 weeks and subsequently sacrificed. The NSKC incorporation in the diet did not exert any adverse effect on caecal fermentation although the weight of caecum and its contents was significantly (p<0.01; p<0.05) lower in rabbits fed the diet containing 20% NSKC. Except for blood glucose concentration, none of the blood biochemical constituents (serum urea nitrogen, creatinine, total protein, haemoglobin) and the activities of different enzymes (alanine aminotransferase, asparatate aminotransferase, alkaline phosphatase) varied significantly due to NSKC feeding. A histopathological examination of the vital organs (liver, kidney, heart, spleen, lungs, intestine and stomach) revealed a variable degree of villus atrophy in the intestine and degenerative changes in the liver and tubular epithelium of kidney in some rabbits when NSKC was fed at levels above 10%.

• 자원ㆍ환경경제연구
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• 제13권1호
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• pp.83-117
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• 2004

본 연구는 수도권지역 대기오염 측정망의 오염물질별 연평균 오염도 측정치를 이용하여 최근 10년간의 수도권내 대기오염도의 공간적 분포 및 그 변화를 분석하였다. 분석을 위해 커널확률밀도함수를 추정하고, 또한 지니계수와 엔트로피계열의 불평등지수를 계측하였으며, 분석기간중 오염도의 공간적 분포 변화에 대한 통계적 검정을 실시하였다. 분석결과 최근 10년간 수도권 지역의 $SO_2$, $NO_2$, $O_3$와 CO 등 대기오염물질 오염도의 지역격차는 대체로 일정한 수준을 유지하거나 아니면 완화되는 것으로 나타났다. 또한 순위상관 분석 결과 분석기간 중 오염물질의 공간적 분포에 상당한 정도의 동태적 변화가 있었던 것으로 나타났다.

• Journal of Biosystems Engineering
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• 제17권3호
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• pp.272-284
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• 1992

As a preliminary step toward the development of a multipurpose electrostatic separator for agricultural use, this study investigated the effect of moisture level, geometrical characteristics and the electric field strength of a charging device on the electrostatic charging of brown rice, unhulled paddy, small stones and broken rice that are produced during the milling process. The results are summarized as follows. 1. Average electrostatic charge per unit mass of paddy is greater than that of brown rice. 2. Charge per unit mass of rice kernel increases linearly with moisture content and electric field strength of the charging device, presenting no correlations with length or thickness of rice kernel. 3. Frequency distributions in electrostatic charge per unit mass of paddy and brown rice kernels indicated that the portion, not overlapped, ranged from 10 to 29% with Japonica rice and from 32 to 49% with Indica rice. 4. The difference in moisture content between paddy and brown rice must be over 6%, if they are to be electrostatically separated to over 95%. 5. Theoretical portions of brown rice to be separated from a mixture primarily by the electrostatic charge and secondarily by the length or by the thickness were 95~100% and 27~76%, respectively. 6. Frequency distribution of electrostatic charge for broken kernels overlapped that of paddy and brown rice, which the small stones didn't.

• Asian-Australasian Journal of Animal Sciences
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• 제13권5호
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• pp.720-728
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• 2000

The different products of neem (Azadirachta indica) are utilized for variety of purposes in industry, health and animal agriculture in the Indian subcontinent. The cake from seeds after oil extraction is a good source of nutrients (CP: 35-38%; EE: 4.5-5.5%; CF: 12-15%; Ca: 0.75%; P: 0.45% on DM), and in particular, the one out of its kernel is proteinaceous and is relatively balanced in its amino acid and mineral profile. But the cake is toxic and bitter to taste owing to triterpenoids (nimbin, salannin, azadirachtin), which restricts its safe inclusion in livestock diet. Several feeding trials with raw cake have revealed poor palatability and adverse performance among different categories of livestock and poultry. Internal organ changes included histological alteration in intestine, liver, kidney and distruption of spermatogenesis and ovarian activity. Ruminants appears to tolerate reasonably higher levels of the cake and to a limited low levels of dietary inclusion also proved to be tolerable in monogastric farm animals. Debitterization through solvent (hexane, ether) extraction, water washing, alkali (NaOH, 1.5, 2.5 or 3%, wt/wt) soaking and urea (1.5 or 3%, wt/wt) - ammoniation have been tried with appreciable success in improving the palatability and nutritive value of the cake. For enhanced utilization, decortication of neem seeds is to be done effectively at industrial level with maximum oil recovery. The resultant proteinaceous kernel by-product could be a cheaper unconventional protein supplement after suitable processing.

• 대한임베디드공학회논문지
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• 제2권4호
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• pp.214-220
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• 2007

Recently, most embedded systems have the multi-functions mixed the hardware with the software. The existing sequence programming methods are not suitable to implement the embedded system with multi-functions. So, it can be overcome the limit of a facility implementation by introducing the operating system in system. Also, due to the requirement about the better convenient and comfortable meeting or lecture environment, the necessity of electronic white-board is getting higher. Specially, the education using multimedia information is much more desirable for various and improved lecture at the high school and the university. But the sequence program which have been managed in existing electronic white-board system has some difficulties to achieve the software-oriented systems which has to accomplish many functions. In this paper, we propose the method to implement a facility of electronic white-board through using the embedded linux with excellent performance. The embedded linux presents the powerful software environment for the implementation of an embedded system and makes the realization of many various functions easy because it follows kernel characteristics of linux. In this paper, we describe the details for the structure of hardware, kernel source and device driver of a developed electronic white-board.