• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.8
• /
• pp.1743-1749
• /
• 2011

The multimedia data for video-on-demand(VOD) service has large, continuous and real time characteristics. The frequent disk I/O operations takes much time and decrease the system performance in multimedia services. Therefore the efficient buffer management is needed in order to reduce the disk accesses to multimedia data. This paper addresses how to increase the buffer hit ratio and the number of users in a multimedia service like VOD by increasing the utility of buffer. This paper also simulated various resource management algorithms and strategies and evaluated, compared and analyzed their performances.

• Proceedings of the KAIS Fall Conference
• /
• 2009.05a
• /
• pp.829-834
• /
• 2009

최근 건설프로젝트가 대형화 복잡화됨에 따라 건설산업의 안전사고 재해자수는 매년 증가추세를 보이고 있다. 각 건설사에서 개발되어 활용하고 있는 건설안전관리시스템의 형식적인 운용과 참여자들에게 시각적인 자료 제공의 미비로 이해도가 떨어지는 시스템을 사용하고 있는 것이 주요 원인으로 분석된다. 따라서 최근 부각되어지는 증강현실시스템(Augmented Reality, AR)을 이용하여 실제 현장과 동일한 환경에서 시각화된 3D시뮬레이션을 통하여 사용자 이해도와 현장감을 높일 수 있는 시스템 개발이 요구되어진다. 본 연구에서는 건설안전관리 시스템의 효율적인 의사소통 지원이 가능하도록 개선된시각화 기술을 적용하여 "증강현실 기반 안전관리시스템"의 인터페이스 구성을 제안하였다. 이를 위해 건설안전관리의 이론적 고찰과 시스템을 분석하고, 시각화 개선을 위한 증강현실시스템을 분석하였다. 이를 통해 도출된 시각화 화면 구성요소를 조합하여 "증강현실기반 안전관리시스템의 안전대책 시뮬레이션 VIEW"를 제안하였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.14 no.3
• /
• pp.227-234
• /
• 1989

In this paper, a new receiver for a frequency-hopped multilevel FSK system for mobile Communications is presented. This new receiver provides an implementation advantage by eliminating unecessary energy detection of all the frequency channels. A performace analysis of the proposed system is carried out by using the union bound. We show that an optimim number of message bits that minimize the word error probability exists for a given number of simultaneous users. This scheme is a generalization of the MFSK system that allows the message bits to be uaried, making it possible for designers to increase the flexibility of implementation. Error probabilities are calculated in the case of fixed bandwidth and fixed tone repetition number. The effect of using error-correcting coding is considered.

• Research in Community and Public Health Nursing
• /
• v.1 no.1
• /
• pp.172-173
• /
• 1989

본 연구는 전국의 보건진료원이 하는 업무를 분석하여 우리나라 보건진료원 제도 정착에 도움을 주는 기초자료를 제공하는 연구의 일환으로 강원도 지역에서 실시하였다. 연구대상은 강원도에 있는 보건진료원 전수로 하였고 이중 응답자수는 108명이었다. 연구도구는 문헌과 간호교육자들에 의해 작성 된 구조화된 설문지를 사용하였으며 수집된 자료는 SPSS를 이용하여 빈도, 백분율, 평균 및 피어슨 상관계수를 구하였고 유의성 검정을 위해서 t-test, ANOVA의 통계방법을 사용하였다. 본 연구결과를 통하여 얻은 결론은 다음과 같다. 1) 조사대상자인 보건진료원의 평균 연령이 31.5세이며 과반수의 보건진료원이 30세 미만 이었고 기혼자가 마혼자보다 약간 많았다. 보건진료원의 반수 이상이 현재 가족과 동거하고 있었고 학력은 3년제 간호전문대학 졸업자가, 경력은 3년 미만인 사람이 대부분이었으며 종교를 가진 사람이 대부분 이었으며 종교를 가진 사람이 안가진 사람보다 더 많았다. 또한 보건진료원의 근무지역 조건은 대부분이 을지에서 근무하고 있었고 대부분의 보건진료원이 신축된 보건진료소 시설에서 업무를 수행하고 보건진료소 내의 숙소에서 거주하는 것으로 냐타났다. 2) 보건진료원이 담당하는 평균 주민수는 1,660.8명 이었으며 과반수 정도의 보건진료원이 $501\sim1,000$명이 이상적인 적정 담당 주민수라고 생각하고 있었다. 강원도 주민의 연평균 보건진료소 이용자수는 4,099.3명 이었고 이용 주민수가 5,000명 이상인 보건진료소도 11개소 12.9 %나 되었다. 3) 보건진료소 사업대상지역 내에 있는 보건 의료기관은 약방 및 약종상이 62.1 %로 가장 많이 분포되어 있었고 보건지소도 16 %나 사업대상지역 내에 함께 있는 것으로 나타났다. 지역주민의 보건의료기관 이용은 보건진료소가 59.0 % 로 지역주민이 가장 많이 이용하고 있었고 보건 진료원이 가장 많이 이용하는 의뢰기관은 뱅 의원이 66 %, 보건소가 36.4 %로 나타났다. 또한 보건진료소의 보건의료기관과의 협조관계는 보건소와는 과반수 정도가 잘 협조하고 있다고 응답 한 반면 보건지소와 잘 협조하고 있다고 응답한 율은 37.6 % 밖에 안되었다. 4) 보건진료원이 업무영역 수행 정도를 살펴 보면 5점 만점에 통상질환관리가 3.69점, 사업 운영 관리 및 지도는 3.45점, 모자보건 및 가족계획은 3.28 점, 지역사회 조직 및 개발은 3.27 점, 보건정보체계 개발 및 수집은 3.17 점, 사업 계획 수립은 3.14 점, 지역사회 보건관리는 3.13 점의 순으로 나타났다. 보건진료원의 업무영역을 l 일 8 시간으로 하여 l 주 44 시간을 기준으로 측정하면 통상질환관리 18.56시간, 지역사회 보건관리 5.67 시간, 모자보건 및 가족계획 5.52 시간, 사업 운영관리 및 지도 4.10시간, 지역사회 조직 및 개발 3.05 시간, 보건정보체계 개발 및 수집 2.94 시간, 사업계획 수립 2.89시간의 순으로 나타났다. 5) 보건진료원의 업무영역별 수행 소요시간의 상판판계를 살펴보면 지역사펴 조직 및 개발을 위 해 소요한 시간은 사엽계획 수립 소요시간 및 보건정 보체계 관리 소요시간과 순상관관계를, 사업 계획 수립 소요시간은 지역사회 보건관리, 모자보건 및 가족계획 관리 소요시간 및 보건정보체제 관리 소요시간과 순상관관계를 나타냈다. 또한 통상질환관리 소요시간은 지역 사회 조직 및 개발, 사업계획 수립, 지역사회 보건관리와 모자보건 및 가족계획 관리, 사업운영 관리 및 지도, 보건정보체계 관리 소요시간과 역상관관계를 나타내었다. 6) 보건진료원의 총 업무수행 정도를 잘펴보면 업무수행 점수의 평균은 87.5점이었으며 보건진료원의 근무지가 병지이고 보건진료소의 시설상태가 나쁜 경우 업무수행 점수가 높은 것으로 나타났으며 업무수행 정도와는 별 차이가 없었다.

• Information Systems Review
• /
• v.11 no.1
• /
• pp.161-179
• /
• 2009

Nowadays an increasing number of Internet users are running individual websites as Blog or Cyworld. As this type of personal media has a great influence on communication among people, business comes to care about Network Effect, Network Software, and Social Network. For instance, Cyworld created the web service called 'Minihompy' for individual web-logs, and acquired 2.4milion users in 2007. Although many people assumed that the popularity of Minihompy, or Blog would be a passing fad, Cyworld has improved its service, and expanded its Network with various contents. This kind of expansion reflects survival efforts from infinite competitions among ISPs (Internet Service Provider) with focus on enhancing usability to users. However, Cyworld's Network Effect is gradually diminished in these days. Both of low production cost of service vendors and the low searching/conversing costs of users combine to make ISPs hard to keep their market share sustainable. To overcome this lackluster trend, Cyworld has adopted new strategies and try to lock their users in their service. Various efforts to improve the continuance and expansion of Network effect remain unclear and uncertain. If we understand beforehand how a service would improve Network effect, and which service could bring more effect, ISPs can get substantial help in launching their new business strategy. Regardless many diverse ideas to increase their user's duration online ISPs cannot guarantee 'how the new service strategies will end up in profitability. Therefore, this research studies about Network effect of Cyworld's 'Minihompy' using System-Dynamics method which could analyze dynamic relation between users and ISPs. Furthermore, the research aims to predict changes of Network Effect based on the strategy of new service. 'Page View' and 'Duration Time' can be enhanced for the short tenn because they enhance the service functionality. However, these services cannot increase the Network in the long-run. Limitations of this research include that we predict the future merely based on the limited data. We also limit the independent variables over Network Effect only to the following two issues: Increasing the number of users and increasing the Service Functionality. Despite of some limitations, this study perhaps gives some insights to the policy makers or others facing the stiff competition in the network business.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.810-814
• /
• 2003

For the phylogenetic analysis of procaryotes, 16S rRNA gene has been used. In spite of it's common use, so high conservative of 16S rRNA gene limited resolving power, hence other molecule was applied in this study and the result was compared with that of 16S rRNA. COG (Clusters of Orthologous of protein) algorithm revealed that three COGs were only detected in 42 procaryotes ; transcription elongation factor (COG0195), bacterial DNA primase (COG0358) and uridylate kinase (COG0528). Uridylate kinase gene was selected owing to the similarity and one single copy number in each genome. Phylogenetic tree of 16S rRNA gene and uridylate kinase showed similarities and differences. Uridylate kinase may help the problem of very high conservative of 16S rRNA gene in rhylogenetic analysis and it would help to access more accurate discrimination and phylogenetic analysis of bacteria.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.38 no.10
• /
• pp.1085-1091
• /
• 2014

We developed a single-channel thread sensor for a rotary bobbin by optical sensing and analyzed the signal characteristics. A specially designed mount made of ABS (acrylonitrile-butadiene-styrene) resin that encapsulated an optical sensor was fabricated by using a 3D printer and was attached to the rotary bobbin system. Stable control on a weaving machine was achieved by observing the difference in the output signals of an optical sensor system, which vary significantly according to the states of the thread in the weaving operation. The optical sensor effectively detects an unintentional thread cut and run-out during weaving fast enough to enable prompt stopping of the weaving machine, thereby minimizing the loss of expensive fabrics.

• Journal of KIISE
• /
• v.44 no.12
• /
• pp.1296-1306
• /
• 2017

Recently, as the number of Internet of Things users has increased, IETF (Internet Engineering Task Force) has released the CoAP (Constrained Application Protocol). So Internet of Things have been researched actively. However, existing studies are difficult to adapt to streaming service due to low transmission rate that result from buffer underflow. In other words, one block is transmitted one block to client's one request according to the internet environment of limited resources. The proposed scheme adaptively adjusts the rate of CON(Confirmable) message among all messages for predicting the exact network condition. Based on this, the number of blocks is determined by using buffer occupancy rate and content download rate. Therefore it improves the quality of user experience by mitigating playback interruption. Experimental results show that the proposed scheme solves the buffer underflow problem in Internet of Things streaming environment by controlling transmission rate according to the network condition.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.8
• /
• pp.1711-1716
• /
• 2012

Vocational rehabilitation is defined as a process which helps people with disabilities to maintain life of non-disabled people and vocational assessment is a part of it. Traditionally, vocational assessment is performed through using of assessment tools or vocational counseling, but assessment tools are very expensive and we should move to the facilities for the disabled. It is very efficient to apply vocational assessment to people with disabilities using the smart phones which users are expected to surpass thirty million in 2012, because it enables them to access anytime and anywhere. In this paper, we design and implement the mobile aptitude test system on android smart phone OS for people with disabilities. We develop the mobile aptitude test system using the Holland Test which is the assessment tool of career guidance and counseling.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.05a
• /
• pp.248-251
• /
• 2011

Vocational rehabilitation is defined as a process which helps people with disabilities to maintain life of non-disabled people and vocational assessment is a part of it. Traditionally, vocational assessment is performed through using of assessment tools or vocational counseling, but assessment tools are very expensive and we should move to the facilities for the disabled. It is very efficient to apply vocational assessment to people with disabilities using the smart phones which users are expected to surpass ten million in 2011, because it enables them to access anytime and anywhere. In this paper, we design and implement the mobile aptitude test system on android smart phone OS for people with disabilities. We develop the mobile aptitude test system using the Holland Test which is the assessment tool of career guidance and counseling.