• Title/Summary/Keyword: Frequency Resource

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Performance Analysis of Fractional Frequency Reuse Scheme for Enterprise Femtocell Networks (기업형 펨토셀 네트워크에서 부분 주파수 재사용 방법의 성능분석)

  • Kim, Se-Jin
    • Journal of Internet Computing and Services
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    • v.19 no.1
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    • pp.11-17
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    • 2018
  • In this paper, we propose a novel frequency reuse method using the fractional frequency reuse (FFR) for enterprise femtocell networks (EFNs) in which a lot of femtocell base stations (fBSs) are deployed in a buinding, e.g., business companies, department stores, etc, and evaluate the system performance for the downlink of EFNs. First, we introduce the concept of the split reuse method to allocate the frequency bandwidth with considering the interference between the macrocell and femtocell. Then, we propose the resource allocation with the FFR for fBSs of EFNs to reduce the interference and increase the system capacity. Through simulations, we show that the proposed FFR method outperforms a traditional resource allocation method with frequency reuse factor 4 in terms of the mean fUE capacity, total EFN capacity, and outage probability.

The Relationship Among the Components of family Resource Management System. (가정자원관리체계 구성요소간의 관계)

  • 최동숙;이정우
    • Journal of Families and Better Life
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    • v.10 no.2
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    • pp.163-178
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    • 1992
  • This study is focused on causual relationship analysis among the components of family resource management system based on a theory of Deacon and Firebaugh. The system of family resource management is consisted for the component of input like on objective resource and level of resource perception, the component of throughput like a behavior pattern of the family resource management, and the component of output like a degree of the family life satisfaction. The instrument for resource perception level, behavior pattern of family resource management and degree of life satisfaction were developed for this study, and main investigation was executed through 1st and 2nd pre-test. The 800 questionnaire were distributed by cluster sampling to the homemakers in Seoul. The final data used in this study were 703, and analyzed by Cronback's coefficient, factor analysis. frequency. percentage, regression analysis and path analysis, and teated with SAS PC+. Consequently , the findings of this study were accepted hypothesis I, II, II, IV.

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Research on Spectral Interference of Microwave Systems (마이크로웨이브 시스템의 주파수 간섭에 관한 연구)

  • Yang, Jae-Soo;Kim, Yoon-Hyun;Kim, Jin-Young
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.6
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    • pp.241-249
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    • 2012
  • In the many countries, research about ultra wideband wireless transmission technique is widely studied for efficient utilization of frequency resource due to a sudden increase of demand of frequency resource all over the world. The ultra wideband communication system has the some specific advantages. First, it can transmit data with high speed, second short transmission range can increase the frequency reuse rate, and finally it has high security property. However, there is a interference between ultra wideband system and other communication system but study to solve this problem is insufficient. To efficient utilization of limited frequency resource, a novel frequency avoidance technique and setup the standardization of frequency interference must need. So, the purpose of this paper is that increases communication efficiency of microwave communication systems to analyze the technical trends for transmission of the low power device, and to research the implementation and technical research of wireless access network technique of wideband communication systems.

Price Elasticity Response to Gasoline Price Liberalization (휘발유가격 자유화에 따른 가격탄력성의 변화)

  • Kim, Youngduk
    • Environmental and Resource Economics Review
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    • v.11 no.4
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    • pp.525-556
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    • 2002
  • This paper investigates effect of gasoline price liberalization on price elasticity of gasoline demand. By using a model where a consumer optimizes her gasoline consumption and number of visits to gas station, we derive price elasticity of gasoline demand and its response to variation of size and frequency in price changes. It shows that price elasticity is decreased with increase in the size and frequency when the price rises. Since price liberalization increases the frequency but reduces the size, the effect of the liberalization on the price elasticity may not be determined. However, price liberalization can make the elasticity higher when the size reduction effect exceeds the frequency increase effect, which is consistent with empirical evidence provided by existing studies.

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Human Resource Management of Institutional Household - To the Application for Job Analysis of Healthy Families Center Worker (공공가정의 인적자원 관리방안 - 건강가정사 직무분석에의 적용)

  • Song, Hye-Rim
    • Journal of Family Resource Management and Policy Review
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    • v.13 no.1
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    • pp.23-39
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    • 2009
  • This study was an attempt to examine the basic scheme required for the job analysis of healthy family-center workers in the context of human resource management. For this purpose, factors including frequency, importance, priority, and difficulty were examined. The job classification and concrete job activities were extracted from the interviews of eight healthy family-center workers, and these factors were then analyzed from the recordings. From the results of this study, 28 job tasks were collected and the four job types were classified. The results can be used for job analysis and human resource development (HRD). This study suggests that various methods should be used for job analysis and that a large number of samples should be utilized for the further studies.

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Multimedia Ad Hoc Wireless LAMs with Distributed Channel Allocation Based on OFDM-CDMA (OFDM-CDMA에 기반을 둔 분산 채널 할당 구조를 갖는 멀티미디어 Ad Hoc 무선 LAM에 관한 연구)

  • Yang, Hyun-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.5
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    • pp.965-972
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    • 2005
  • We propose a new resource management scheme, Distributed Channel Allocation Protocol (DCAP), for multimedia Ad Hoc Wireless LANs (AWLANS). This scheme implements a Qualify-of-Service (QoS) providing distributed resource management on the Orthogonal Frequency Division Multiplexing-Code Division Multiple Access (OFDM-CDMA) channel architecture. According to the performance evaluation results for MPEG traffic sources, DCAP can be a good choice of resource management scheme for AWLANs supporting multimedia services on the Broadband Wireless Access(BWA)-type physical layer.

Proportional-Fair Downlink Resource Allocation in OFDMA-Based Relay Networks

  • Liu, Chang;Qin, Xiaowei;Zhang, Sihai;Zhou, Wuyang
    • Journal of Communications and Networks
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    • v.13 no.6
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    • pp.633-638
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    • 2011
  • In this paper, we consider resource allocation with proportional fairness in the downlink orthogonal frequency division multiple access relay networks, in which relay nodes operate in decode-and-forward mode. A joint optimization problem is formulated for relay selection, subcarrier assignment and power allocation. Since the formulated primal problem is nondeterministic polynomial time-complete, we make continuous relaxation and solve the dual problem by Lagrangian dual decomposition method. A near-optimal solution is obtained using Karush-Kuhn-Tucker conditions. Simulation results show that the proposed algorithm provides superior system throughput and much better fairness among users comparing with a heuristic algorithm.

Proportional Fair Scheduling Algorithm in OFDMA-Based Wireless Systems with QoS Constraints

  • Girici, Tolga;Zhu, Chenxi;Agre, Jonathan R.;Ephremides, Anthony
    • Journal of Communications and Networks
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    • v.12 no.1
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    • pp.30-42
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    • 2010
  • In this work we consider the problem of downlink resource allocation for proportional fairness of long term received rates of data users and quality of service for real time sessions in an OFDMA-based wireless system. The base station allocates available power and subchannels to individual users based on long term average received rates, quality of service (QoS) based rate constraints and channel conditions. We formulate and solve a joint bandwidth and power optimization problem, solving which provides a performance improvement with respect to existing resource allocation algorithms. We propose schemes for flat as well as frequency selective fading cases. Numerical evaluation results show that the proposed method provides better QoS to voice and video sessions while providing more and fair rates to data users in comparison with existing schemes.

Resource Allocation in Two Hop Relay Network based on PB/MC-CDMA System (PB/MC-CDMA 기반 two-hop 중계 망에서의 자원 할당 방식)

  • Sun, Yan;Lee, Kye-San
    • Journal of Satellite, Information and Communications
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    • v.5 no.1
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    • pp.94-99
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    • 2010
  • In this paper, we discuss a proposed two hop relay network with PB/MC-CDMA(partial block MC-CDMA) technique. The main advantages of PB/MC-CDMA system are the increased cell capacity and the high quality of performances. In the system, we employ relay scheme to focus on the coverage reduction and hotspot problem, hotspot is a location where a cluster of users are blocked or dropped for the reason of insufficient frequency resources. Frequency resource allocation scheme is put forward in a three cells system according to each problem. The simulation result shows the performance of the two hop transmission is better than the direct transmission and the proposed network can support much more users to relief hotspot effect compared to the conventional one.

Increase of ICSI Efficacy with Hyaluronic Acid-Binding Sperm for Low Aneuploidy Frequency in Pig

  • Park, Chun-Young;Uhm, Sang-Jun;Song, Sang-Jin;Kim, Kwag-Sung;Hong, Seung-Bum;Chung, Kil-Saeng;Lee, Hoon-Taek
    • Proceedings of the KSAR Conference
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    • 2003.06a
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    • pp.26-26
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    • 2003
  • Hyaluronic acid (HA)-binding sites have been shown the diagnostic potential fur assessment of sperm maturity, which is related to male fertility. This study was designed to evaluate chromosomal patterns in porcine embryos produced by in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) with non- or HA-binding sperm (HABS). For binding of sperm with HA, sperm incubated in 10 ${mu}ell$ drop containing HA (0.8 mg/ml)-agarose (0.8%) mixture for 15 min. IVF and ICSI with non- or HA-bound sperm examined with matured oocytes at 44 hr after in vitro maturation. Embryos were cultured in 50 ${mu}ell$ of NCSU 23 containing 0.5% BSA for 5 days and then in 50 ${mu}ell$ of NCSU 23 containing 10% FBS for 2 days. For the evaluation of chromosomal aneuploidies, chromosome 1 sub-metacentric specific probe was used in sperm and embryos by fluorescence in situ hybridization (FISH). The frequency of aneuploidy sperm for chromosome 1 was 6.25%. The significant differences following IVF and ICSI with non- or HA-bound sperm were not observed in blastocyst formation rates (18.6, 23.5, and 23.8%) and cell number (61.8 $\pm$ 12.5, 55.5 $\pm$ 7.3, and 59.3 $\pm$ 9.6). Moreover, the percentage of diploidy in 4-cell stage embryos was 57.1% (IVF), 68.8% (ICSI), and 76.3% (ICSI-HABS). These results suggest that HA-binding sites may be a material for selection of normal sperm for ICSI. Therefore HA selection of normal sperm may be reduce the loss to embryonic mortality prior to embryo transfer in pig.

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