• Title/Summary/Keyword: UDC

Search Result 45, Processing Time 0.025 seconds

Unsynchronized Duty-cycle Control for Sensor Based Home Automation Networks

  • Lee, Dong-Ho;Chung, Kwang-Sue
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.6 no.4
    • /
    • pp.1076-1089
    • /
    • 2012
  • Home automation networks are good environments for merging sensor networks and consumer electronics technologies. It is very important to reduce the energy consumption of each sensor node because sensor nodes operate with limited power based on a battery that cannot be easily replaced. One of the primary mechanisms for achieving low energy operation in energy-constrained wireless sensor networks is the duty-cycle operation, but this operation has several problems. For example, unnecessary energy consumption occurs during synchronization between transmission schedules and sleep schedules. In addition, a low duty-cycle usually causes more performance degradation, if the network becomes congested. Therefore, an appropriate control scheme is required to solve these problems. In this paper, we propose UDC (Unsynchronized Duty-cycle Control), which prevents energy waste caused by unnecessary preamble transmission and avoids congestion using duty-cycle adjustment. In addition, the scheme adjusts the starting point of the duty-cycle in order to reduce sleep delay. Our simulation results show that UDC improves the reliability and energy efficiency while reducing the end-to-end delay of the unsynchronized duty-cycled MAC (Media Access Control) protocol in sensor-based home automation networks.

Form Divisions of ICC (국제백진분류법연구 (02) - 일반형식구분표의 전개 -)

  • Jeong Pil-Mo
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.26
    • /
    • pp.3-33
    • /
    • 1994
  • The author have devised the main table of International Centesimal Classification(ICC). This is the second study of ICC. And so, this study intends to devise a new and reasonable form divisions for the ICC. This study analyses the 'standard subdivisions' of DDC and the 'general form divisions' of UDC and LCC, to investigate the problems included among them. And then, it devises the three tables of 'Internal form divisions, External form divisions, and Special form divisions' in two digit of arabic numerals.

  • PDF

A study of auxiliary schedules in classification (분류표에서 사용하는 보조표에 대한 연구)

  • 정해성
    • Journal of Korean Library and Information Science Society
    • /
    • v.28
    • /
    • pp.193-218
    • /
    • 1998
  • The purpose of this study is to analyze and compare of the structure of auxiliary schedules using in DDC, UDC, CC and BC. Auxiliary schedule whish are a n.0, ppended to schedule of all schemes of classification. They consist of items of form of presentation relationship, time, place, languages, racial, ethnic, national groups and persons and phase relation and the symbols of the different items can be added to classification numbers.

  • PDF

A Comparative Study on the Knowledge Classification and Library Classification System of Botany (식물학의 학문분류와 문헌분류 체계에 관한 비교 연구)

  • Kim, Jeong-Hyen
    • Journal of Korean Library and Information Science Society
    • /
    • v.39 no.3
    • /
    • pp.369-386
    • /
    • 2008
  • The purpose of this study is investigate to compare with knowledge classification and library classification system of botany. First, the knowledge field of botany is mainly classified in morphology, physiology, ecology, taxonomy, genetics, evolution and others by the study object of plants. Second, the division of plants is treated in the field of taxonomy, that is, a lower subdivision study of botany, and Engler's classification is still prevalent in the taxonomy. Third, in library classification, KDC, NDC, UDC and CC adopted the Engler's classification, but DDC and LCC was taken of the Bentham & Hooker's classification. In the Engler's classification, plants are arranged by evolution's order, from lower vegetation to higher vegetation, but Bentham & Hooker's classification is arranged in the reverse order. Forth, it is desirable that every plants(482-489) of KDC' botany are subdivided by the attribute or structure of plants being treated in the general botany as if they are subdivided in the DDC or CC.

  • PDF

A Study on the Improvement of the Classification System on Archives and Records Management Studies in KDC (한국십진분류법 기록관리학 분야 분류체계 개선에 관한 연구)

  • Park, Su-Hyun;Lee, Myoung-Gyu
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.27 no.3
    • /
    • pp.25-50
    • /
    • 2016
  • Archives and Records Management Studies is being developed its own independent domains. However, the existing library classification scheme such as the KDC don't properly reflect the characteristics of Archives and Records Management Studies. This classification scheme has the irrational part of the arrangement of the subject items and should be required to rearrange subdivision of the subject areas. In this study, According to the characteristics of Archives and Records Management Studies, It is set up 8 subject areas, Records Management (General), the law and polices of records management, the collection and appraisal of the records, the documentary organization, recording information services, preservation of the records, archives management, archives and records center, etc. After analyzing the major contemporary library classification system such as KDC, DDC, NDC, UDC, LCC, then It is suggested that improvement measures through analyzing classification status and keywords of the Archives and Records Management data contained in Korean National Bibliography. In Archives and records management studies, The contents of the eight subject areas related to the field are changed to allow integration with KDC 028.

A Study on the Improvements of Food and Culture in Dewey Decimal Classification System (음식문화 분야의 DDC 분류체계 개선방안에 관한 연구)

  • Chung, Yeon-Kyoung;Choi, Yoon-Kyung
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.21 no.1
    • /
    • pp.43-57
    • /
    • 2010
  • The purposes of this study are to examine how food and culture and Korean foods are reflected in the classification systems and to propose improvements of DDC to classify various subjects related to the materials of food and culture. For the study, six classification systems - DDC(Dewey Decimal Classification), UDC(Universal Decimal Classification), LCC(Library of Congress Classification), KDC(Korean Decimal Classification), NDC (Nippon Decimal Classification), China Library Classification - were analyzed in aspects of eating and drinking customs, eating etiquette, nutrition and diet, food and drink, meal and table service, beverage technology, and food technology. As a result, there were few headings about Korean food in six classification systems and it was necessary for DDC to have new headings for classifying Korean and Asian traditional foods and table services. Due to the literary warrant in classification systems, it is required to publish and disseminate various Korean food recipes and publications to add new headings or notes in future classification systems.

Phase Relations in Colon Classification (콜론분류법에서의 상(相)관계)

  • Kim, T.S.
    • Journal of the Korean Society for information Management
    • /
    • v.4 no.2
    • /
    • pp.47-61
    • /
    • 1987
  • Main advantages of an analytico-synthetic scheme are its flexibility and its ability to cope with new subjects as they arise. Accordingly the synthetic scheme can keep pace with changes in knowledge more easily than an enumerative scheme because new subjects often merely involve fresh combinations of basic unit parts already listed. The findings of the study are as follows: 1. Each part of the components of a complex subject is called phase in CC and we are able to obtain three levels of phase relations such as intra-facet phase relation, intra-array - phase relation and inter-subject phase relation. 2. Different digits are used in CC to represent different varieties of phase relation in each levels. 3. The mode of phase relation may be taken to indicate the strength of bond between the phase and may form a new main subject. 4. In the rules and grammar of the phase relation the extension of two-phase subject is possible up to any extent theoritically. 5. Phase relation in DDC was introduced in the 18th edition, but there was no provision for the kind and the level of phase relation. 6. Colon(:) of the UDC is used to represent phase relation but there was also no provision for the kind and the level of phase relation.

  • PDF

A Study on Building Internal Tables in Christianity of the 5th Edition of Korean Decimal Classification (기독교 분야 내부보조표 설정에 관한 연구 - 한국십진분류법 제5판을 중심으로 -)

  • Jeong, Yu Na;Chung, Yeon-Kyoung
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.24 no.3
    • /
    • pp.29-51
    • /
    • 2013
  • The purpose of this study is to develop internal tables in Christian religion in the 5th edition of Korean Decimal Classification. The scope of the Christianity, its structure of various classification schemes, and the concepts of internal tables were analyzed. The contents of several textbooks were analyzed for the scope of the discipline and the classification schemes and internal tables of DDC, UDC, NDC, LCC, Classification of the Library of Union Theological Seminary and the Classification of the Korea Theological Library were compared. And then, internal tables in Bible, sermon, worship, church history were built and those tables were evaluated by librarians and experts in the fields. And finally, internal tables of the Christiainity and new headings were suggested. New internal tables in Christianity will increase the effectiveness of information retrieval and it will provide a foundation for developing internal tables in other disciplines.

Hybrid Power Management System Using Fuel Cells and Batteries

  • Kim, Jae Min;Oh, Jin Seok
    • Journal of information and communication convergence engineering
    • /
    • v.14 no.2
    • /
    • pp.122-128
    • /
    • 2016
  • In the future, hybrid power management systems using fuel cells (FCs) and batteries will be used as the driving power systems of ships. These systems consist of an FC, a converter, an inverter, and a battery. In general, an FC provides steady-state energy; a battery provides the dynamic energy in the start state of a ship for enabling a smooth operation, and provides or absorbs the peak or dynamic power when the load varies and the FC cannot respond immediately. The FC voltage range is very wide and depends on the load; Therefore, the FC cannot directly connect to the inverter. In this paper, we propose a power management strategy and design process involving a unidirectional converter, a bidirectional converter, and an inverter, considering the ship's operating conditions and the power conditions of the FC and the battery. The presented experimental results were verified through a simulation.

Performance and Applications of High Efficiency Phosphorescent OLED Technology

  • Hack, M.;Lu, M.K.;Kwong, R.;Weaver, M.S.;Tung, Y.J.;Chwang, A.;Brown, J.J.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2003.07a
    • /
    • pp.169-173
    • /
    • 2003
  • Universal Display Corporation (UDC), together with its University partners at Princeton University and the University of Southern California, are developing high-efficiency electrophosphorescent OLED devices, based on triplet emission. Recent results show both excellent device efficiencies and good lifetimes for the commercialization of low power consumption, full-color, passive and activematrix OLED displays. We also show that phosphorescent devices may be driven by low cost amorphous silicon backplanes, and discuss the benefits of using our proprietary top emission OLED device architecture.

  • PDF