• Title/Summary/Keyword: D2D Coverage

Search Result 237, Processing Time 0.029 seconds

A Study on the Planning of Nationwide Indexing Services for Korea (전국색인지간행협동체제 편성방안에 관한 연구)

  • Choi Sung Jin
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.12
    • /
    • pp.39-86
    • /
    • 1985
  • The main purpose of the present study is to survey the major iudexing bulletins of national nature in Korea, to define such problem areas as lacunae, duplicates and limitation in coverage in the indexing services currently available in Korea, and to make some suggestions for action for improving the existing indexing services in the light of general principles and the tradition and constraints unique to Korea. The major findings and conclusions reached at this study are summarised as follows: (A) A new indexing bulletin of general nature covering the entire field needs to be created in each of the following fields without an established indexing service available for the outcome of research and development activities in Korea. (1) Philosophy (2) Religion (3) Pure sciences (4) Art (5) Language (6) Literature (7) History (B) A new specialised indexing bulletin needs to be created in each of the following fields where indexing services are heavily utilised but no, or only partial, indexing service is available. (1) Social sciences (a) Statistics (b) Sociology (c) Folklore (d) Military science (2) Pure sciences (a) Mathematics (b) Physics (c) Chemistry (d) Astronomy (e) Geology (f) Mineralogy (g) Life sciences (h) Botany (i) Zoology (3) Applied sciences (a) Medicine (b) Agriculture (c) Civil engineering (d) Architectural engineering (e) Mechanical engineering (f) Electrical engineering (g) Chemical engineering (h) Domestic science (C) Publication of the indexing bulletins suggested in A and B above may be ideally carried on by a qualified and dependable learned society established in the respective fields and designated by the Minister of Education, and should be financially supported from the public fund under the provisions of Art. 27 of the Scientific Research Promotion Act of 1979. (D) The coverage and contents of the four indexing bulletins in the field of banking and financing published by the Library of the Bank of Korea are similar and considerably duplicated. It is, therefore, suggested that the four indexing bulletins are combined in one to form a more comprehensive and efficient bibliographical tool in the field and it is further developed into a general guide to the literature produced in the entire field of economics in Korea by gradually expanding its subject coverage. (E) For the similar reasons stated in D, the Index to the Articles on North Korea and the Catalogue of Theses on North Korea, both publisheds by the Ministry of Unification Library, are suggested to make into one. The Index to the Articles of the Selected North Korean Journals and the Index to the Articles of the North Korean Journals in Microfilm Housed in the Ministry of Unification Library, both published by the same Library, are also suggested to be combined in one. (F) The contents of the Catalogue of the Reports Submitted by Government Officials Who Have Travelled Abroad, published by the National Archives are included in the Index to the Information Materials Related to Government Administration, published by the National Archives. The publication of the former is hardly justified. (G) The contents of the Index to Legal Literature published by the Seoul National University Libraries and those of the Law Section of the Index to Scholastic Works published by the National Central Library are nearly identical. One of the two indexes should cease to be published. (H) Though five indexes are being published in the field of political science and four in the field of public administration, their subject coverage is limited. Naturally, these indexes are little usable to many other researchers in the two fields. A comprehensive index covering all the specialised areas in each field needs to be developed on one or all the existing indexes. (I) It is suggested that the Catalogue of the Scholastic Works on Curricula published by the National Central Library expands its subject coverage to become a more usable and effective index to all the researchers in the field of education. (J) The bimonthly Index to Periodical Articles and the specialised index by subject series published by the National Assembly Library, and the Index to Scholastic Works published by the National Central Library are expected to increase their coverage and frequency of publication to be used more effectively and more efficiently by all users in all fields till the indexing bulletins suggested in this study will fully be available in Korea.

  • PDF

Prediction and analysis of noise level of outdoor areas in roadside apartment complexes (도로변 아파트 단지 옥외공간의 소음도 예측 및 분석)

  • Shin, Hye-Kyung;Yang, Hong-Seok;Kim, Myung-Jun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2014.10a
    • /
    • pp.885-887
    • /
    • 2014
  • Outdoor spaces in an apartment complex have been enlarged by the increased underground car parking. It has become accepted as important place for acoustic comfort of resident. This paper attempts to determine the noise exposure to the outdoor area in 21 apartment complexes built within 5 years. The results showed that the average noise level of outdoor area ranged from 37.6dB(A) to 67.2dB(A). And the percentage of areas below the noise level of 55dB(A) range 0.1% to 95.0%. The analysis on correlations shows that the traffic volume and building coverage have significant effects on noise level.

  • PDF

Signal Coverages of DGPS Beacon Stations in Korea (우리나라 DGPS 보정국의 위치보정신호의 이용범위)

  • Ahn, Jang-Young;Choi, Chan-Moon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.40 no.1
    • /
    • pp.47-53
    • /
    • 2004
  • For the purpose of comparison between the designed coverage and actual coverage of Korean DGPS (Differential Global Position System) beacon stations, we have received the ship‘s positions with states and IDs of their stations on the navigation route of Jeju-Tianjin by automatic selection mode of DGPS receiver and on them of Jeju-Inchun and Jeju-Vladibostok by manual mode. Also in case that some obstructions were on propagation routes from DGPS beacon stations to receiving positions, a restriction on available ranges of DGPS beacon signals was investigated. The results obtained are as follows : 1. The coverage of Korean DGPS beacon stations was designed 100NM (Nautical mails) at 40.0dB(over ${\mu}$V/m). But the actual coverages of them according to their stations and propagation routes were 0.3-3.6 times as wide as designed coverage. 2. In case that the propagation route of beacon signals from DGPS beacon stations was on the sea, the propagation distance of north direction from the stations was longer than south direction. 3. The coverages of Echongdo and Ulungdo stations were 366NM on the yellow sea and 342.3NM on the east sea of Korea respectively, and were widest than any other stations. 4. The coverage of Marado station on the south and yellow seas of Korea was very unstable because of the Halla mountain on the propagation route. Maximum receiving range to be measured by automatic selection mode of DGPS receiver was 145NM on the route of Jeju-Tianjin on June 22-July 1, 2002. Minimum receiving range to be not measured by manual selection mode was 28.7NM on the route of Jeju-Inchun on June 26-28, 2003

Optimization and Improvements of Field Uniformity in a Reverberation Chamber with Schroeder Diffusers (Schroeder 확산기를 이용한 전자파 잔향실내의 필드 균일도 향상 및 최적화에 관한 연구)

  • Kim, Jung-Hoon;Rhee, Joong-Geun
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.18 no.4 s.119
    • /
    • pp.372-378
    • /
    • 2007
  • This paper presents an improvement of field uniformity in a reverberation chamber with QRDs(Quadratic Residue Diffuser) and also shows the optimal dimension of the QRDs. The QRD is designed for $1{\sim}3\;GHz$ frequency band and the FDTD(finite-Difference Time-Domain) method is used to analyze the field characteristics. At 2 GHz, the standard deviation of test volume in the reverberation chamber is the smallest when the QRD has $30{\sim}60\;%$ coverage of one side of the reverberation chamber and the field uniformity is worsened when the coverage of the QRD is either below 20 % or above 70 % of the area of the side wall. Particularly, the standard deviation of test volume in the reverberation chamber with 30 % coverage of QRD is improved by 1.53 dB compared to that of the reference chamber with no QRDs.

A Broadband Digital Step Attenuator with Low Phase Error and Low Insertion Loss in 0.18-${\mu}m$ SOI CMOS Technology

  • Cho, Moon-Kyu;Kim, Jeong-Geun;Baek, Donghyun
    • ETRI Journal
    • /
    • v.35 no.4
    • /
    • pp.638-643
    • /
    • 2013
  • This paper presents a 5-bit digital step attenuator (DSA) using a commercial 0.18-${\mu}m$ silicon-on-insulator (SOI) process for the wideband phased array antenna. Both low insertion loss and low root mean square (RMS) phase error and amplitude error are achieved employing two attenuation topologies of the switched path attenuator and the switched T-type attenuator. The attenuation coverage of 31 dB with a least significant bit of 1 dB is achieved at DC to 20 GHz. The RMS phase error and amplitude error are less than $2.5^{\circ}$ and less than 0.5 dB, respectively. The measured insertion loss of the reference state is less than 5.5 dB at 10 GHz. The input return loss and output return loss are each less than 12 dB at DC to 20 GHz. The current consumption is nearly zero with a voltage supply of 1.8 V. The chip size is $0.93mm{\times}0.68mm$, including pads. To the best of the authors' knowledge, this is the first demonstration of a low phase error DC-to-20-GHz SOI DSA.

The Abstracting Services in Korea: The Present State, Problems and Some Suggestions for Action in the Future (우리나라의 초록시스템 - 현황, 문제 및 개선방안)

  • Choi, Sung-Jin
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.6 no.1
    • /
    • pp.133-160
    • /
    • 1984
  • The main purpose of the present study is to survey the major abstracting bulletins of national nature in Korea, to define such problem areas as lacunae, duplicates and limitation in coverage in the abstracting services currently available in Korea, and to make some suggestions for action for improving the abstracting services in the light of general principles and the tradition and situations unique to Korea. The major conclusions reached at this study are summarised as follows: (A) A new abstracting bulletin of general nature covering the whole field needs to be created in each of the following fields where no established abstracting service is available for the outcome of research and development activities in Korea. (1) Language (2) Religion (3) Art (4) Language (5) Literature (6) History (B) A new specialised abstracting bulletin needs to be created in each of the following fields of science where abstracting services limited in coverage are partially available. (a) Statistics (b) Sociology (c) political science (d) Public administration (e) Law (f) Folk lore (g) Military science (2) Pure sciences (a) Mathematics (b) Chemistry (c) Astronomy (d) Geology (e) Mineralogy (f) Life sciences (g) Botany (h) Zoology (3) Applied sciences (a) Agriculture (b) Architectural engineering (c) Mechanical engineering (d) Electrical engineering (e) Chemical engineering (f) Manufacturing industry (g) Domestic science (C) Publication of the abstracting bulletins suggested in (A) and (B) above may be ideally carried on by a qualified learned society established in the respective field. and should be financially supported by the public fund under the provisions of Art. 27 of the Research Promotion Act of 1979. (D) The current practice of adding the author's abstract and keywords to each of the records of the "Doctoral Theses in Humanities and Social Sciences" part of the" Catalogue of Doctoral and Master's Theses Submitted to the Universities in Korea" published by the National Assembly Library should be applied to all the other parts, i. e. to the parts of the "Master's Theses in Humanities and Social Sciences" and of the "Doctoral and Master's Theses in Natural Sciences': which will not only increase the Catalogue's use value but also discourage appearance of various theses abstracts of individual academic institutions such as the" Abstracts of the Doctoral and Master's Theses Submitted to Korea Advanced Institute of Science and Technology" which will in turn reduce inefficiency involved in the abstracting services at national level. (E) A general abstracting bulletin covering most part of the outcome of research and development activities in Korea other than that covered by the existing abstracts needs to be created to be temporarily. used till the abstracting journals suggested in this study will be fully available. A realistic way of having such a bulletin may be to expand the present coverage of "The Abstracts of the Reports of the Government-sponsored Projects" currently published by Korean Research Foundation.

  • PDF

Design of Effective Reliability Tests for New Products (신제품 개발에 따른 효과적인 신뢰성 시험 설계)

  • Park, B.H.;Jang, J.S.;Kim, G.Y.;Lee, J.H.;Kim, S.J.;Chan, S.I.;Jeong, K.Y.;Kim, D.J.;Lee, C.B.
    • Journal of Applied Reliability
    • /
    • v.9 no.2
    • /
    • pp.107-119
    • /
    • 2009
  • Reliability tests should be designed to verify whether reliability requirements are satisfied or not effectively and efficiently. The portion of reliability requirements that a reliability test scheme composed of different types of tests can cover is defined as test coverage in software engineering. For the cases of hardwares, to be effective, a reliability test scheme should enhance the test coverage. This study is to develop an evaluation method of test coverage for a reliability test scheme proposed for new products. Case studies are also given.

  • PDF

Soil Surface Fixation by Direct Sowing of Zoysia japonica with Soil Improvement on the Dredged Soil Slope (해저준설토 사면에서 개량제 처리에 의한 한국들잔디 직파 지표고정 공법에 관한 연구)

  • Jeong, Yong-Ho;Lee, Im-Kyun;Seo, Kyung-Won;Lim, Joo-Hoon;Kim, Jung-Ho;Shin, Moon-Hyun
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.14 no.4
    • /
    • pp.1-10
    • /
    • 2011
  • This study was conducted to compare the growth of Zoysia japonica depending on different soil treatments in Saemangeum sea dike, which is filled with dredged soil. Zoysia japonica was planted using sod-pitching method on the control plot. On plots which were treated with forest soil and soil improvement, Zoysia japonica seeds were sprayed mechanically. Sixteen months after planting, coverage rate, leaf length, leaf width, and root length were measured and analyzed. Also, three Zoysia japonica samples per plot were collected to analyze nutrient contents. Coverage rate was 100% in B treatment plot(dredged soil+$40kg/m^3$ soil improvement+forest soil), in C treatment plots (dredged soil+$60kg/m^3$ soil improvement+forest soil), and D treatment plots (dredged soil+$60kg/m^3$ soil improvement), while only 43% of the soil surface was covered with Zoysia japonica on control plots. The width of the leaf on C treatment plots (3.79mm) was the highest followed by D treatment (3.49mm), B treatment (2.40mm) and control plots (1.97mm). Leaf and root length of D treatment was 30.18cm and 13.18cm, which were highest among different treatments. The leaf length of D treatment was highest followed by C, B, and A treatments. The root length of D treatment was highest followed by C, A, and B treatments. The nitrogen and phosphate contents of the above ground part of Zoysia japonica were highest in C treatment, followed by D, B, and A treatments. The nitrogen and phosphate contents of the underground part of Zoysia japonica were highest in D treatment, followed by C, A, and B treatments. C and D treatments showed the best results in every aspect of grass growth. The results of this study could be used to identify the cost effective way to improve soil quality for soil surface fixation on reclaimed areas using grass species.

A Design of Broadband Biconical Antenna with Tapered Section (테이퍼 구조를 갖는 광대역 바이코니컬 안테나의 설계)

  • Kim, Jun-Kyu;Lee, In-Jae;Yoon, Hyun-Bo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.17 no.11 s.114
    • /
    • pp.1096-1104
    • /
    • 2006
  • In this paper, the broadband antenna for the combined base station of Cellular/PCS/IMT-2000/Wibro and S-DMB services is designed and the proposed antenna allows having sufficient coverage for each service band. In order to get the broadband impedance matching, the tapered sections are applied on the both terminus of hi-conical respectively. The design parameter is calculated and simulated by using FDTD method. As a result, the measured bandwidth of the proposed antenna is $0.79GHz{\sim}2.93GHz$ and the gain is distributed from 5.5 dBi up to 8.19 dBi.

Development of a Simulator for CT-2 Coverage Prediction and Cell Planning by GIS-Based Approach (GIS를 기반으로 한 CT-2 서비스 영역 예측 및 셀설계 시뮬레이터 개발)

  • Im, Jong-Su;Lee, Bong-Seok;Lee, Mun-Su
    • The Transactions of the Korea Information Processing Society
    • /
    • v.6 no.5
    • /
    • pp.1342-1350
    • /
    • 1999
  • A new design procedure for micro cellular coverage prediction is presented here on this paper, which contains a new propagation analysis algorithm based on processing of vector data representing roads and buildings which mainly affect the propagation phenomena in micro-cell environments. The propagation analysis algorithm presented here has been developed to aim at the practical application for micro-cellular systems such as PCS or CE-2. As all the vectors used here are of closed poly lines, i.e., polygons, a simplified ray path search technique can be developed not only to determine if the calculation points are on the road polygons and but also to calculate the amount of blockage by buildings. The result shows a capability of predicting path loss with an RMS error of 5dB or lower.

  • PDF