• 제목/요약/키워드: Primary standard

검색결과 1,098건 처리시간 0.027초

An Experimental Implementation of a Cross-Layer Approach for Improving TCP Performance over Cognitive Radio Networks

  • Byun, Sang-Seon
    • Journal of Information Processing Systems
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    • 제12권1호
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    • pp.73-82
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    • 2016
  • In cognitive radio networks (CRNs), the performance of the transmission control protocol (TCP) at the secondary user (SU) severely drops due to the mistrigger of congestion control. A long disruption is caused by the transmission of primary user, leading to the mistrigger. In this paper, we propose a cross-layer approach, called a CR-aware scheme that enhances TCP performance at the SU. The scheme is a sender side addition to the standard TCP (i.e., TCP-NewReno), and utilizes an explicit cross-layer signal delivered from a physical (or link) layer and the signal gives an indication of detecting the primary transmission (i.e., transmission of the primary user). We evaluated our scheme by implementing it onto a software radio platform, the Universal Software Radio Peripheral (USRP), where many parts of lower layer operations (i.e., operations in a link or physical layer) run as user processes. In our implementation, we ran our CR-aware scheme over IEEE 802.15.4. Furthermore, for the purpose of comparison, we implemented a selective ACK-based local recovery scheme that helps TCP isolate congestive loss from a random loss in a wireless section.

Anatomical Site Classification for Implant Insertion:ASCIi

  • Jeong, Seung-Mi;Chung, Chae-Heon;Engelke, W.
    • 대한치과보철학회지
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    • 제38권3호
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    • pp.321-327
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    • 2000
  • Statement of Problem. As a standard means of diagnostics, an orthopantomogram(OPT) permits to measure the vertical and mesiodistal dimension of available bone at the desired implant site with the help of suitable radioopaque references. Based on the clinical investigation of the dentition and the edentulous sites, information upon the width of the implant site can be obtained and documented in the dental scheme. Both findings permit together systematic primary planning for endosteal implants. Purpose of Study. Contents of the present article are the representation of a semiquantitative classification of available bone with the aim to simplify the primary phase of a systematic implant planning. Results. Thus the ASCIi- system permits a clear protocol of bone findings for the implant case with all information available during the primary appointment for treatment planning as a basis of further diagnostic and therapeutic measures. Conclusion. With the ASCIi system, important parameters such as alveolar height and sub-crestal alveolar width can be documented systematically, easily and time saving in the dental scheme as a basis for exact treatment planning.

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Factors Affecting the Dissolution Behavior of Metals from Binary Alloys

  • Han, Kenneth N.
    • 자원리싸이클링
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    • 제10권1호
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    • pp.49-55
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    • 2001
  • The strategy of recovering metals from scrap is in general much different from primary sources. One of the main differences between the treatment of scrap and that of primary sources lies with the fact that metals are frequently associated with other met-als to form alloys in scrap, while metals occur in primary sources as oxides or sulfides. In this paper, factors affecting the dis-solution behavior of metals from various alloy systems have been reviewed and discussed. Specific examples have been drawn from Au/Ag, Au/cu and Ag/cu systems. Results of the dissolution behavior of various metals from these alloys have been reviewed and compared to the dissolution behavior of single metal systems in various lixiviants such as acids, cyanide and ammonia. It has been observed that the presence of other metals in alloys would significantly affect the dissolution rate of the metal in question. The leaching behavior of metals from homogeneous alloys relies on the chemical interaction between atoms in the lattice of the alloys, while that from heterogeneous alloys is affected by galvanic interaction established in the solution The manner in which the dissolution of a certain metal is influenced by surrounding metals has been discussed in terms of pas-sive and noble nature of the metal in relation to the neighboring metals. The role of the standard electrochemical Potential of these metals on the selective dissolution for a given lixiviant has also been discussed.

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중풍의 예후 인자 및 기능 평가방법에 관한 문헌적 고찰 (A Literal Study about the Apoplexy Prognosis of Primary Factors and the Method of the Function Assessment)

  • 조은희;권정남;김영균
    • 대한한의학회지
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    • 제21권4호
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    • pp.138-147
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    • 2000
  • Objectives and Method : In this study, I have investigated what kind of primary factors detennine the apoplexy prognosis, and the method of the function assessment about the apoplexy by inquiry into the literature on this subject Results and Conclusions : 1. The primary factors to have an effect upon the appoplexy are : the location of Pungsa; whether five organs ki is existent or not; pulse feeling; tongue condition; whether or not the patient produces stool or urine; for males, the left side; for females, the right side ; whether or not the patient sweats; consciousness; vital signs; and the region and size of disease and brain hernia. 2. MBI is often used because it is considered to be objective, simple, and highly reliable. But its absence of a legal recognition assessment is a major incongruence. 3. Inclusive and standard assessment are key points in the reinforecement by AM of legal recognition assessment, but it takes a lot of time and is not endowed with adding an extra weight and is vague to the division between the communication and social recognition grade. 4. AI is useful and easy to evaluate the mental ability, the capacity for locomotion and the daily activities inclusively.

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Block-Time of Arrival/Leaving Estimation to Enhance Local Spectrum Sensing under the Practical Traffic of Primary User

  • Tran, Truc Thanh;Kong, Hyung Yun
    • Journal of Communications and Networks
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    • 제15권5호
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    • pp.514-526
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    • 2013
  • With a long sensing period, the inter-frame spectrum sensing in IEEE 802.22 standard is vulnerable to the effect of the traffic of the primary user (PU). In this article, we address the two degrading factors that affect the inter-frame sensing performance with respect to the random arrival/leaving of the PU traffic. They are the noise-only samples under the random arrival traffic, and the PU-signal-contained samples under the random leaving traffic. We propose the model in which the intra-frame sensing cooperates with the inter-frame one, and the inter-frame sensing uses the time-of-arrival (ToA), and time-of-leave (ToL) detectors to reduce the two degrading factors in the inter-frame sensing time. These ToA and ToL detectors are used to search for the sample which contains either the ToA or ToL of the PU traffic, respectively, which allows the partial cancelation of the unnecessary samples. At the final stage, the remaining samples are input into a primary user detector, which is based on the energy detection scheme, to determine the status of PU traffic in the inter-frame sensing time. The analysis and the simulation results show that the proposed scheme enhances the spectrum-sensing performance compared to the conventional counter-part.

국민학교 아동의 발음조사 (The Investigation of Pronounciation of Primary School Students)

  • 소진명;박성준;김인술;김정희
    • 대한기관식도과학회:학술대회논문집
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    • 대한기관식도과학회 1972년도 춘계종합 학술대회 초록집
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    • pp.2.1-2
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    • 1972
  • 사회가 안정되어 감에 따라 질병에 대한 일차적인 치료와 더불어 2차적인 재활과 사회의 복지에 중점을 두고 있다. 우리는 흔히 재활이라고 하면 지체부자유자들에 대한 재활에만 관심을 두고 있으나 그와 못지 않게 언어 장애에 대한 재활도 병행, 발전해야 될 것이다. 이지음 시급한 연구 대상으로 되어있는 "공해"의 한가지로써 "언어 공해" 즉 몇몇의 발음 장애, 언어장애자들로 인해서 많은 수의 어린이들이 발음이 정확하지 못한 경향이 있다. 이에 우리 과에서는 전주시내외에 있는 5개 국민학교 학생 921명에 대한 언어조사를 하여 그 결과를 관찰했다 이 결과는 대단한 것은 못되나 앞으로 우리나라 언어 병리학의 발전에 조금이라도 도움이 되고 어린이들의 언어 공해를 지양하는데 힘이 되기 바라는 바이다.

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원전 격납건물 누설시험용 무선데이터전송을 적용한 시험장치 개발 (Leakage Rates Measurement System Development of NPP Primary Containment using Wireless Data Communication Method)

  • 류재규;손창호;황희정;김건수;최경식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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    • pp.916-919
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    • 2003
  • In this paper, we deal with a development of measurement system to apply the leakage rates test of primary containment in nuclear power plant. The measurement test about leakage rates in primary containment is one sort of test to prove safety of nuclear power plant. The parameters which are measured to calculate leakage rates are drybulb temperature, dew point temperature(or relative humidity), absolute pressure and flow. Overall, the measurement system consists of sensor module for data acquisition of the parameters, transfer module for wireless data communication and control module to control system and to calculate leakage rates. Because existing measurement systems are difficult to set in field, we pursued convenience of use, we applied wireless data communication and individual form module using battery. We also changed for the better in confidence. Recently, we are developing a drybulb temperature and a dew point temperature sensor module. We describe about function of developed measurement system, its standard and an plan for verification of measurement system.

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Novel Adaptive Blanking Regulation Scheme for Constant Current and Constant Voltage Primary-side Controlled Flyback Converter

  • Bai, Yongjiang;Chen, Wenjie;Yang, Xiaoyu;Yang, Xu
    • Journal of Power Electronics
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    • 제17권6호
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    • pp.1469-1479
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    • 2017
  • Primary-side regulation (PSR) scheme is widely applied in low power applications, such as cell phone chargers, network adapters, and LED drivers. However, the efficiency and standby power requirements have been improved to a high standard due to the new trends of DOE (Department Of Energy) Level VI and COC (Code Of Conduct specifications) V5. The major drawbacks of PSR include poor regulation due to inaccurate feedback and difficulty in acquiring acceptable regulation. A novel adaptive blanking strategy for constant current and constant voltage regulation is proposed in this paper. An accurate model for the sample blanking time related to transformer leakage inductance and the metal-oxide-semiconductor field-effect transistor (MOSFET) parasitic capacitance is established. The proposed strategy can achieve accurate detection for ultra-low standby power. In addition, numerous control factors are analyzed in detail to eliminate the influence of leakage inductance on the loop stability. A dedicated controller integrated circuit (IC) with a power MOSFET is fabricated to verify the effectiveness of the proposed control strategy. Experimental results demonstrated that the prototype based on the proposed IC has excellent performance.

Establishment and Identification of a Debao Pony Ear Marginal Tissue Fibroblast Cell Line

  • Zhou, X.M.;Ma, Y.H.;Guan, W.J.;Zhao, D.M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제17권10호
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    • pp.1338-1343
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    • 2004
  • The Debao pony ear marginal tissue fibroblast cell line (NDPEM 2/2) was uccessfully established using either primary explant technique or collagenase technique. The characterizations of the cell line were identified as following: the cells were adherent and of density limitation; population doubling time (PDT) of cells made with the two techniques were 35.9 h and 48 h, respectively; chromosome analysis showed that the frequency of cell chromosome number to be 2n=64 was 91.3%-92.8%. Confirmed by isoenzyme analysis, this cell line had no cross- contamination. Tests for microbial contamination from bacteria, fungi, virus or mycoplasma were negative. This newly established cell line meets all the standard quality controls of ATCC. It will provide a precious genetic resource for the conservation of the Debao pony breed, as well as effective experimental material for genetic studies on Debao ponies.

원자로 주 배관계의 진동 건전성 시험 (Verification Test for Primary Reactor Piping in Nuclear Power Plant)

  • 김연환;김희수;구재량;배용채;이현
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 추계학술대회논문집
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    • pp.74-79
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    • 2002
  • The piping verification tests were performed in order to verify the structural integrity during initial operation of the reactor coolant systems and the primary heat transportation systems of nuclear power plants by KEPRI in Korea. The tests were conducted at full operating temperature and pressure. The objective is to evaluate the possibility of excessive load generating on piping, piping supports, and reactor structures etc. in the steady normal operation and expected pump transient conditions. As a result, the measured vibrations have been shown acceptable level according to ASME/ANSI OMa-Standard, Part 3.

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