• 제목/요약/키워드: group of units

검색결과 1,100건 처리시간 0.034초

스트리밍 서버를 위한 멀티미디어 파일 시스템 최적화 (Optimizing a Multimedia File System for Streaming Severs)

  • 박진연;김두한;원유집;류연승
    • 한국정보과학회논문지:시스템및이론
    • /
    • 제31권5_6호
    • /
    • pp.268-278
    • /
    • 2004
  • 전통적인 텍스트기반의 입출력과 달리, 멀티미디어 자료의 재생은 저장장치에서 일정한 대역폭을 보장을 필요로 한다. 대용량 서버에서 가장 많이 사용되는 유닉스 계열의 파일 시스템은 대역폭 보장이 필요하고, 순차적 접근특성을 가지고 있는 멀티미디어 자료 재생에 많은 개선의 여지를 가지고 있는 것이 사실이다. 본 논문에서는 유닉스 계열 파일 시스템의 단점을 극복하고 동영상 실시간 재생에 적합한 파일 시스템 구조를 연구 개발한 결과를 기술하고자 한다. 본 파일 시스템은 세 가지 설계 목표를 가지고 개발되었다. 첫 번째는 순차적 접근 부하에 대한 효과적 지원이다. 순차적 접근 특성을 효과적으로 지원하기 위해서는 트리기반의 데이타 블록구성이 아닌 연결리스트기반의 데이타 블록 구성방식을 채택한다. 두 번째는 파일 단편화 방지이다. 순차적 읽기에 있어서 과도한 디스크 탐색(Seek) 작업은 디스크의 효율성에 부정적인 영향을 미친다. 이를 효과적으로 극복하기 위하여 파일은 데이타 유닛 그룹(Data Unit Group)이라 불리는 단위의 집합으로 구성되며, 데이타 유닛 그룹은 연결리스트를 이용하여 구성되었다. 세 번째는 논리적 유닛에 기반한 파일 접근방식의 지원이다. 멀티미디어 파일은 비디오 프레임이나 오디오 샘플들의 집합으로 구성되어 있으며, 이들은 각기 다른 크기를 가지고 띤다. 따라서, 이들에 대한 임의접근 (Random Access)를 지원하기 위해서 각 논리적 유닛의 위치를 나타내는 인덱스를 파일 메타구조에 포함하였다. 이 부분은 트리구조를 이용하여 구성한 것이다. 실험을 통해서 파일 시스템의 성능을 리눅스 기반의 EXT2 파일 시스템, SGI 사에서 개발한 XFS 파일 시스템과 비교하였으며, 본 논문에서 제안하는 파일 시스템이 기존 리눅스 기반의 EXT2 그리고 SGI 사의 XFS 파일 시스템 보다 더 우수한 성능을 나타내는 것으로 입증되었다.

Chitosan-Ascorbate 함유 홍국이 고지방 식이 흰쥐의 혈청지질에 미치는 영향 (Effect of Beni-Koji with Chitosan-Ascorbate on Serum Lipid Profile of Rats Fed a High Fat Diet)

  • 신진기;이상일;권중호;김순동
    • 동아시아식생활학회지
    • /
    • 제15권5
    • /
    • pp.524-530
    • /
    • 2005
  • Dietary effect of soyfiber beni-koji (SBK) with chitosan-ascorbate (CA) on the level of serum lipids in rats fed a high fat diet was investigated The experimental groups which were divided into high fat diet control group(HC-group), $2\%\;SBK+0.1\%$ CA mixture diet group(CA1-group), $2\%\;SBK+0.15\%$ CA mixture diet group(CA2-group), and $2\%\;SBK+0.2\%$ CA mixture diet group (CA2-group) were fed for 4 weeks. Weight gains in CA2- and CA3-group were $5.3\%\;and\;9.5\%$ lower than that of HC-group, respectively, while there was no significant difference in feed intakes, feed efficiency ratio and organs weight Level of serum triglyceride in $C_3-group\;was\;21\%$ lower than that of HC-group. Level of serum total cholesterol and LDL-cholesterol in CA2- and CA3-group were $22.1\~22.7\%\;and\;58.6\~64.3\%$ lower than those of HC-group, respectively. Atherogenic index decreased with the higher level of CA. Level of lipid peroxide in CA3-group was $24\%$ lower than that of HC-group, while there was no significant difference in GSH(Glutathione-S-transferase) content O type activities of XOD(xanthine oxidase) in the treated groups were lower, especially the activity in CA3-group was $51.6\%$ lower than that of HC-group. Also, O/T ratio of XOD was lower, showing $21.7\~23.5\%$ in treated groups and $34.0\%$ in HC-group(p<0.05). GST activities were 332.52 units in HC-group and $350.28\~355.63$ units in the treated groups, but there were no significant differences among them.

  • PDF

GROUP ACTIONS IN A UNIT-REGULAR RING WITH COMMUTING IDEMPOTENTS

  • Han, Jun-Cheol
    • East Asian mathematical journal
    • /
    • 제25권4호
    • /
    • pp.433-440
    • /
    • 2009
  • Let R be a ring with unity, X the set of all nonzero, nonunits of R and G the group of all units of R. We will consider some group actions on X by G, the left (resp. right) regular action and the conjugate action. In this paper, by investigating these group actions we can have some results as follows: First, if E(R), the set of all nonzero nonunit idempotents of a unit-regular ring R, is commuting, then $o_{\ell}(x)\;=\;o_r(x)$, $o_c(x)\;=\;\{x\}$ for all $x\;{\in}\;X$ where $o_{\ell}(x)$ (resp. $o_r(x)$, $o_c(x)$) is the orbit of x under the left regular (resp. right regular, conjugate) action on X by G and R is abelian regular. Secondly, if R is a unit-regular ring with unity 1 such that G is a cyclic group and $2\;=\;1\;+\;1\;{\in}\;G$, then G is a finite group. Finally, if R is an abelian regular ring such that G is an abelian group, then R is a commutative ring.

GROUP ACTIONS IN A REGULAR RING

  • HAN, Jun-Cheol
    • 대한수학회보
    • /
    • 제42권4호
    • /
    • pp.807-815
    • /
    • 2005
  • Let R be a ring with identity, X the set of all nonzero, nonunits of Rand G the group of all units of R. We will consider two group actions on X by G, the regular action and the conjugate action. In this paper, by investigating two group actions we can have some results as follows: First, if G is a finitely generated abelian group, then the orbit O(x) under the regular action on X by G is finite for all nilpotents x $\in$ X. Secondly, if F is a field in which 2 is a unit and F $\backslash\;\{0\}$ is a finitley generated abelian group, then F is finite. Finally, if G in a unit-regular ring R is a torsion group and 2 is a unit in R, then the conjugate action on X by G is trivial if and only if G is abelian if and only if R is commutative.

의미 단위 분해를 통한 주치와 병증 용어 연계 연구 (A Study of Disassembling Major Indication Terms into Minimum Meaning Units and Linking to Diseases)

  • 김안나;오용택;김상균;김상현;장현철
    • 대한한의학방제학회지
    • /
    • 제21권2호
    • /
    • pp.72-80
    • /
    • 2013
  • Objectives : Ontology is a good tool to represent the knowledge and has developed for Traditional Korean Medicine(TKM) in Korea Institute of Oriental Medicine. There are a lot of TKM terms, which have a complex meaning, especially major indication terms of medicinal treatment and terms of symptom and disease. These complex meaning terms result in the low linkage between major indication terms of medicinal treatment and terms of symptom and disease in TKM ontology. We studied to enhance the percentage of the linkage among those data in TKM ontology. Methods : We disassembled major indication terms of medicinal treatment into minimum meaning units and then linked them to enhance the percentage of the linkage among medicinal material, formula and disease ontology based on Traditional Korean Medicine. To retain objectivity, several experts of Korean Medicine used a web-based tool that supports users in refining terms and disassembling them into the minimum meaning efficiently. Results : The outcome shows that the percentage of the linkage among medicinal material, formula and disease ontology increased. By linking disassembled major indication terms to symptoms and diseases, the amount of information for medicinal materials and formulas also increased quantitatively in comparison with given formula for diseases in disease ontology. Conclusions : By this study, disassembled data increases the percentage of linkage between diseases and medicinal treatments. And the applicability of TKM ontology is also increased.

Current status of opioid prescription in South Korea using narcotics information management system

  • Soo-Hyuk Yoon;Jeongsoo Kim;Susie Yoon;Ho-Jin Lee
    • The Korean Journal of Pain
    • /
    • 제37권1호
    • /
    • pp.41-50
    • /
    • 2024
  • Background: Recognizing the seriousness of the misuse and abuse of medical narcotics, the South Korean government introduced the world's first narcotic management system, the Narcotics Information Management System (NIMS). This study aimed to explore the recent one-year opioid prescribing patterns in South Korea using the NIMS database. Methods: This study analyzed opioid prescription records in South Korea for the year 2022, utilizing the dispensing/administration dataset provided by NIMS. Public data from the Korean Statistical Information Service were also utilized to explore prescription trends over the past four years. The examination covered 16 different opioid analgesics, assessed by the total number of units prescribed based on routes of administration, type of institutions, and patients' sex and age group. Additionally, the disposal rate for each ingredient was computed. Results: In total, 206,941 records of 87,792,968 opioid analgesic units were analyzed. Recently, the overall quantity of prescribed opioid analgesic units has remained relatively stable. The most prescribed ingredient was oral oxycodone, followed by tapentadol and sublingual fentanyl. Tertiary hospitals had the highest number of dispensed units (49.4%), followed by community pharmacies (40.2%). The highest number of prescribed units was attributed to male patients in their 60s. The disposal rates of the oral and transdermal formulations were less than 0.1%. Conclusions: Opioid prescription in South Korea features a high proportion of oral formulations, tertiary hospital administration, pharmacy dispensing, and elderly patients. Sustained education and surveillance of patients and healthcare providers is required.

거주평형에 따른 소비자 홈 패션 구매 행동 및 선호도 연구 (A Study on Consumers Home Fashion Buying Behavior and Preferences Based on Housing Size)

  • 김칠순;박수연
    • 복식문화연구
    • /
    • 제13권1호
    • /
    • pp.34-46
    • /
    • 2005
  • The purpose of this study was to research buying behavior and home fashion preferences based on housing size. The target consumers were Korean women, aged 20~40s who reside in the Seoul & Kyunggido areas. We distributed questionnaires to 650 women. However, only 600 questionnaires were used for the statistical analysis. Data analyses were conducted with SPSS program on the frequency, Chi-square test, cluster analysis, t-test and ANOVA. The results of this study are as follows: 1. The considering factors for purchasing such as brand, trends coordinating existing furnishings with new products and functionality were significantly associated with housing size. The buyers who reside in bigger size homes. over 40 pyung place higher value on brand name, trends. or coordinating existing furnishing with new products than residents in smaller units. However, women who live in smaller units place higher value on functionality when purchasing home fashion products. Considering factors such as brand, trend, and materials were also significantly associated with segmented age group; 40~49 age group considered brand, trend, and materials more than 20~29 age group. The group who are highly interested in home fashion considered design/color, rand, coordination, and functionality than the group who are low interested in home fashion. 2. Residents in over 40 pyung homes buy home fashion products at department stores, while residents in less than 39 pyung homes buy them at discounted store. 3. Respondents preferred solid colors more than patterns. However, they favored character pattern for textile bedding products for their children. 4. there is also a statistical difference in preferences for types of window treatments between large ad small housing sizes. Residents living in over 40 pyung preferred tie-back/cottage curtain, while residents living in less than 29 pyung preferred Roman shade style.

  • PDF

Simple Presentness in Modular Group Algebras over Highly-generated Rings

  • Danchev, Peter V.
    • Kyungpook Mathematical Journal
    • /
    • 제46권1호
    • /
    • pp.57-64
    • /
    • 2006
  • It is proved that if G is a direct sum of countable abelian $p$-groups and R is a special selected commutative unitary highly-generated ring of prime characteristic $p$, which ring is more general than the weakly perfect one, then the group of all normed units V (RG) modulo G, that is V (RG)=G, is a direct sum of countable groups as well. This strengthens a result due to W. May, published in (Proc. Amer. Math. Soc., 1979), that treats the same question but over a perfect ring.

  • PDF

그룹 테크놀러지에서의 기계 및 부품군을 형성하기 위한 발견적 해법 (A heuristic algorithm for forming machine cells and part families in group technology)

  • 이백
    • 대한산업공학회지
    • /
    • 제22권4호
    • /
    • pp.705-718
    • /
    • 1996
  • A similarity coefficient based algorithm is proposed to solve the machine cells and part families formation problem in group technology. Similarity coefficients are newly designed from the machine-part incidence matrix. Machine cells are formed using a recurrent neural network in which the similarity coefficients are used as connection weights between processing units. Then parts are assigned to complete the cell composition. The proposed algorithm is applied to 30 different kinds of problems appeared in the literature. The results are compared to those by the GRAFICS algorithm in terms of the grouping efficiency and efficacy.

  • PDF

구성주의 접근의 요리활동이 유아의 과학적 태도와 창의성에 미치는 영향 (The Effects of a Constructivist Approach to Cooking Activities on Young Children's Scientific Attitudes and Creativity)

  • 박고운;김선영
    • 아동학회지
    • /
    • 제32권1호
    • /
    • pp.141-156
    • /
    • 2011
  • This research centers around an experiment conducted to determine the relative effectiveness of constructivist cooking activities as compared to traditional cooking activities for young children. Forty-six children, aged five years in two kindergarten classes were assigned to a experimental and comparative group. The experimental and comparative group participated in 12 units. The experimental group participated in the constructivist cooking activities, while the comparative group participated in the traditional cooking activities. Analysis of covariance revealed significant differences between the mean scores of the two groups on the posttests for scientific attitudes and creativity, indicating that the children in the experimental group performed significantly better on the tests than the children in the comparative group. The results of this study suggest that such constructivist cooking activities are able to improve the scientific attitudes and creativity of young children.