• Title/Summary/Keyword: time-dependency

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Impact Assessment of Plug-in Hybrid Electric Vehicles on Electric Utilities (플러그인 하이브리드 자동차의 시장 형성 시의 전력망에의 영향 분석)

  • Roh, Chul-Woo;Kim, Min-Soo
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2001-2006
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    • 2008
  • The most concerning issue of these days is the energy crisis by increasing threat of dependency on foreign oil and its volatility itself. In the situations, the PHEV is drawing attention for the next generation's car which could give a chance to decrease the dependency on foreign oil. As well as, the Korean electric power infrastructure is a strategic national asset that is under utilized most of the time. With the proper changes in the operational paradigm, it could generate and deliver necessary energy to charge the PHEVs which could penetrate the market within few years. In doing so, it would reduce greenhouse gas emissions, improve the economics of the electricity industry, and reduce the energy dependency. This paper investigate the technical potential and impacts of using the existing idle capacity of the electric infrastructure in conjunction with the emerging PHEVs technology to meet the majority of daily energy needs of the Korean LDV fleet.

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An Error Control Algorithm for Wireless Video Transmission based on Feedback Channel (무선 비디오 통신을 위한 피드백 채널 기반의 에러복구 알고리즘의 개발)

  • 노경택
    • Journal of the Korea Society of Computer and Information
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    • v.7 no.2
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    • pp.95-100
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    • 2002
  • By feedback channel, the decoder reports the addresses of corrupted macroblocks induced by transmission errors back to the encoder With these negative acknowledgements, the encoder can make the next frame having propagated errors by using forward dependency based on GOBs and MBs of the frame happening transmission errors. The encoder can precisely calculate and track the propagated errors by examining the backward motion dependency for each of four comer pixels in the current encoding frame until before-mentioned the next frame. The error-propagation effects can be terminated completely by INTRA refreshing the affected macroblocks. Such a fast algorithm further reduce the computation and memory requirements. The advantages of the low computation complexity and the low memory requirement are Particularly suitable for real-time implementation.

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Many-objective joint optimization for dependency-aware task offloading and service caching in mobile edge computing

  • Xiangyu Shi;Zhixia Zhang;Zhihua Cui;Xingjuan Cai
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.5
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    • pp.1238-1259
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    • 2024
  • Previous studies on joint optimization of computation offloading and service caching policies in Mobile Edge Computing (MEC) have often neglected the impact of dependency-aware subtasks, edge server resource constraints, and multiple users on policy formulation. To remedy this deficiency, this paper proposes a many-objective joint optimization dependency-aware task offloading and service caching model (MaJDTOSC). MaJDTOSC considers the impact of dependencies between subtasks on the joint optimization problem of task offloading and service caching in multi-user, resource-constrained MEC scenarios, and takes the task completion time, energy consumption, subtask hit rate, load variability, and storage resource utilization as optimization objectives. Meanwhile, in order to better solve MaJDTOSC, a many-objective evolutionary algorithm TSMSNSGAIII based on a three-stage mating selection strategy is proposed. Simulation results show that TSMSNSGAIII exhibits an excellent and stable performance in solving MaJDTOSC with different number of users setting and can converge faster. Therefore, it is believed that TSMSNSGAIII can provide appropriate sub-task offloading and service caching strategies in multi-user and resource-constrained MEC scenarios, which can greatly improve the system offloading efficiency and enhance the user experience.

A Study on the Object-Oriented Program Slicing using Module Class Dependency Graph (모듈 클래스 종속 그래프를 이용한 객체지향 프로그램 슬라이싱에 관한 연구)

  • Kim, Un-Yong;Jeong, Gye-Dong;Choe, Yeong-Geun
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.7
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    • pp.1805-1816
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    • 1999
  • This paper presents the Module Class Dependency Graph for expressing the dependency relations between classes effectively. The object-oriented language is developed independently at design time, and consists of relationship between classes. Therefore we need to consider these characteristics of independence, and to express effectively the relation of classes which is existed in class hierarchy. In the System Dependence Graph and Class Dependence Graph, the relationship of classes is not expressed. To express the class relationship, we propose the Module Class Dependence Graph, and we verify the effectiveness of this method applying to object constructor, inheritance relationship and dynamic binding. Also, we presents the expressing method of parameter to identify the member data of classes. Using this Module Class Dependency Graph, we can analyze the relationship of module class correctly at design time. This method can be applied to reverse engineering, testing, visualization and other various fields to analyze system.

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Households' Characteristics, Forest Resources Dependency and Forest Availability in Central Terai of Nepal

  • Panta, Menaka;Kim, Kyehyun;Lee, Cholyoung
    • Journal of Korean Society of Forest Science
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    • v.98 no.5
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    • pp.548-557
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    • 2009
  • For centuries, forests have been a key component of rural livelihood. They are important both socially and economically in Nepal. Firewood and fodder are the basic forest products that are extracted daily or weekly basis in most of the rural areas in Nepal. In this study, a field survey of 100 households was conducted to examine the degree of forest dependency and forest resource availability, households' livelihood strategy and their relationship with forest dependency in Chitwan, Nepal. A household' response indexes were constructed, Gini coefficient, Head Count Poverty Index (HCI) and Poverty Gap Index (PGI) were calculated and one way ANOVA test was also performed for data analysis. Data revealed that 82/81% of all households were constantly used forest for firewood and fodder collection respectively while 42% of households were used forest or forest fringe for grazing. The Forest Product Availability Indexes (FPAI) showed a sharp decline of forest resources from 0.781 to 0.308 for a 20-yr time horizon while timber wood was noticeably lowered than the other products. Yet, about 33% of households were below the poverty threshold line with 0.0945 PGI. Income distribution among the household showed a lower Gini coefficient 0.25 than 0.37 of landholdings size. However, mean income was significantly varies with F-statistics=246.348 at P=0.05 between income groups (rich, medium and poor). The extraction of firewood, fodder and other forest products were significantly different between the income group with F-statistics=16.480, 19.930, 29.956 at P=0.05 respectively. Similarly, landholdings size and education were also significantly different between the income groups with F-statistics=4.333, 5.981 at P=0.05 respectively. These findings suggested that income status of households was the major indicator of forest dependency while poor and medium groups were highly dependent on the forests for firewood, fodder and other products. Forest dependency still remains high and the availability of forest products that can be extracted from the remaining forestlands is decreasing. The high dependency of households on forest coupled with other socioeconomic attributes like education, poverty, small landholders and so on were possibly caused the forest degradation in Chitwan.Therefore, policy must be directed towards the poor livelihood supporting agenda that may enhance the financial conditions of rural households while it could reduce the degree of forest dependency inspired with other income generating activities in due course.

Development of Design Process Management Model using Dependency Structure Matrix for Constructability (시공성을 위한 Dependency Structure Matrix 기반의 설계 프로세스 관리 모델 개발)

  • Park, Moon-Seo;Ham, Young-Jib;Lee, Hyun-Soo;Kim, Woo-Young
    • Korean Journal of Construction Engineering and Management
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    • v.11 no.5
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    • pp.65-74
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    • 2010
  • The design with construction knowledge and experience can eliminate inefficiency in the process of construction and improve productivity in all phase of construction project. To utilize constructability knowledge most effectively in design phase, the information must be made available to the design team at the proper point in time. Current methods for effective utilization of constructability knowledge have focused on the structuralization of constructability knowledge such as checklist, which lack the consideration of the proper point in time. However, constructability knowledge which is used at the inapposite point in time consequently leads to unnecessary rework. To minimize this inefficiency and improve productivity, project manager needs to consider the design process and know what constructability knowledge is required for specific design activities. This paper therefore presents a design process management using Dependency Structure Matrix (DSM) that focus on information flows between design activities and constructability knowledge. We expect that the results of this paper will support that design process management become comprehensive management related to every phase of construction project beyond design review or inspection in design phase, and be used as a basis of the integration of design and construction.

The Effect of Positive and Negative Parenting Attitudes on Adolescents' Smartphone Dependency in the Time of Convergence : Focusing on the Mediating Effect of Poor Attachment (융복합시대 부모의 긍정적양육태도와 부정적양육태도가 청소년의 스마트폰 의존도에 미치는 영향 : 또래애착의 매개효과)

  • Kim, Kwang-Sook;Shin, Kyoung Sil;Lee, Hoon-Min
    • Journal of Convergence for Information Technology
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    • v.7 no.4
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    • pp.139-149
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    • 2017
  • This study tries to examine the effect of positive and negative parents' attitudes on adolescents' smartphone dependency, and prove the meditating effect of poor attachment between the two variables in the times of convergence. For the study, the data from the Korean Children and Youth Panel Survey were analyzed by utilizing the path analysis, the data from 1,971. The results are as follows: First, positive and negative parents' attitudes influenced adolescents' poor attachment. Second, positive and negative parents' attitudes had a effect on adolescents' smartphone dependency. Third, parents' attttudes directly influenced adolescents' smart phone dependency and its' effect was indirectly mediated by the subjects's poor attachment.

Influences of characteristics of the long-term care elderly and caregivers on caregivers' stress (장기요양보호 노인 및 부양자특성이 부양자의 스트레스에 미치는 영향)

  • Kim, Yong-hee;An, Jeong-shin
    • 한국노년학
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    • v.29 no.3
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    • pp.1183-1196
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    • 2009
  • The purpose of this study was to investigate the influences of characteristics of the long-term care elderly and caregivers on caregivers' stress. The data of this study were collected from 105 long-term care elderly caregivers with 3 grade in Pusan, Daegu, and Gyung-buk area. The results showed that each stress of caregivers was influenced by diverse characteristics in various ways. Time-dependent stress of caregivers was influenced by elderly dependency and caregivers' health. Self-development stress of caregivers was influenced by elderly dependency, caregivers' health, caregivers' age, and relationship quality. Physical stress of caregivers was influenced by elderly dependency and caregivers' health. Social stress of caregivers was influenced by elderly dependency, caregivers' health, and relationship quality. Emotional stress of caregivers was influenced by relationship quality between the elderly and caregivers. These results indicated that the caregivers' stress was influenced not only physical characteristics of the elderly and the caregivers but also relational characteristics.

A Study on the Temperature Dependency Affecting Setting and Strength Development of Concrete Using Mineral Admixtures (혼화재 사용 콘크리트의 응결 및 강도발현에 미치는 온도의존성에 관한 연구)

  • Joo, Eun-Hi;Shon, Myeong-Soo;Jeon, Hyun-Kyu;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.11a
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    • pp.707-710
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    • 2005
  • This experimental study investigate temperature dependency affecting setting and strength development of concrete using mineral admixtures such as CKD, FA and BS. For the properties of setting at $5^{\circ}C$, setting time of concrete with mineral admixture was delayed about $3\~14$ hour compared with that of plain concrete. Use of CKD had a desirable effect on reducing setting retard under $5^{\circ}C$ because of $CaCO_3$ of CKD while use of FA and BS retarded setting time greatly. For compressive strength under $5^{\circ}C$, concrete with CKD had the most compressive strength in early age compared with the other mineral admixtures but exhibited slight strength loss in $-5^{\circ}C$ at 28days. Especially, concrete with FA and BS was observed in early stage at low curing temperature because of strength loss remarkably in $-5^{\circ}C$.

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A Control Dependency Analyzer for Workflow (워크플로우 제어 의존성 분석 도구의 구현)

  • Park, Woong;Oh, Jong-Tae;Kim, Kwang-Hoon;Paik, Su-Ki
    • Proceedings of the Korea Information Processing Society Conference
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    • 2000.10a
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    • pp.39-42
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    • 2000
  • 본 논문은 워크플로우 모델링 도구인 ICN(Information Control Net)을 기반으로 하는 워크플로우 제어 의존성 분석을 위한 도구를 구현하였다. 즉, ICN 모델로 정의된 워크플로우의 각 단위업무(Activity)들 간에 존재하는 제어 의존 관계를 표현하기 위한 제어 의존 넷(Control Dependency Net)을 정형적인 방법으로 정의, 표현하였다. 본 논문에서 정의된 제어 의존 넷은 워크플로우 빌드타임(Build-time) 측면과 런타임(Run-time)측면에서 여러 가지 기능을 제공한다. 전자의 측면에서는 워크플로우 모델링시 시멘틱 에러 테스팅 기능을 효과적으로 적용될 수 있으며 후자의 측면에서는 제어 흐름의 동적 변경(dynamic Change)기능의 완결성 및 프로세스 안의 단위업무(Activity) 간의 경로 및 경로 대한 정보를 제공한다.

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