• Title/Summary/Keyword: dual problems

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Design of a CMOS Dual-Modulus Prescaler Using New High-Speed Low-Power TSPC D-Flip Flops (새로운 고속 저전력 TSPC D-플립플롭을 사용한 CMOS Dual-Modulus 프리스케일러 설계)

  • Oh, Kun-Chang;Lee, Jae-Kyong;Kang, Ki-Sub;Park, Jong-Tae;Yu, Chong-Gun
    • Journal of IKEEE
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    • v.9 no.2 s.17
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    • pp.152-160
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    • 2005
  • A prescaler is an essential building block for PLL-based frequency synthesizers and must satisfy high-speed and low-power characteristics. The design of D-flip flips used in the prescaler implementation is thus critical. Conventional TSPC D-flip flops suffer from glitches, unbalanced propagation delay, and unnecessary charge/discharge at internal nodes in precharge phase, which results in increased power consumption. In this paper a new dynamic D-flip flop is proposed to overcome these problems. Glitches are minimized using discharge suppression scheme, speed is improved by making balanced propagation delay, and low power consumption is achieved by removing unnecessary discharge. The proposed D-flip flop is employed in designing a 128/129 dual-modulus prescaler using $0.18{\mu}m$ CMOS process parameters. The designed prescaler operates up to 5GHz while conventional one can operate up to 4.5GHz under same conditions. It consumes 0.394mW at 4GHz that is a 34% improved result compared with conventional one.

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A Study on vibration suppression of dual inertia system using controlling Parameter $\alpha$ of PID controller with 2-degree of freedom (2자유도 PID 제어기의 파라미터 $\alpha$ 추종을 이용한 2관성 시스템의 진동억제)

  • 박재현;추연규;김현덕;박연식
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2004.05b
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    • pp.506-510
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    • 2004
  • A torque transmission system composed of several gears and couplings is flexible. In order to get an exact response of motor, the torsional vibration due to an unexpected change of motor speed must be suppressed. Therefore, it is very important that motor control suppress vibration. Various methods to control it including dual inertia system are proposed. Specially, the method of vibration suppression is that vibration can be suppressed to fee㏈ack the estimated torsion torque via the disturbance observer filter being of normal filter. The suitable Proportional controller and coefficient parameter can be designed using CDM and the torsional vibration also be suppressed, but it has a low degree of adaptability to disturbance. The PID controller can be designed easily, but makes the excessive overshoot and oscillation for system response in the early period. To resolve these problems, simple and practical PID controller with two degree of freedom is proposed recently that it ran improve performance of obeying the reference unconcerned in any disturbance by changing the proportional gain by two degree of freedom parameter. But it has also the defect that parameter a must be changed to obtain the ideal Proportional parameter. On this paper, we design the controller which automatically adjusts parameter u using fuzzy Algorithm to overcome such defects. Also, we compare the proposed method with established one and evaluate them to confirm performance of the designed controller.

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Quantitative Rainfall Estimation for S-band Dual Polarization Radar using Distributed Specific Differential Phase (분포형 비차등위상차를 이용한 S-밴드 이중편파레이더의 정량적 강우 추정)

  • Lee, Keon-Haeng;Lim, Sanghun;Jang, Bong-Joo;Lee, Dong-Ryul
    • Journal of Korea Water Resources Association
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    • v.48 no.1
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    • pp.57-67
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    • 2015
  • One of main benefits of a dual polarization radar is improvement of quantitative rainfall estimation. In this paper, performance of two representative rainfall estimation methods for a dual polarization radar, JPOLE and CSU algorithms, have been compared by using data from a MOLIT S-band dual polarization radar. In addition, this paper presents evaluation of specific differential phase ($K_{dp}$) retrieval algorithm proposed by Lim et al. (2013). Current $K_{dp}$ retrieval methods are based on range filtering technique or regression analysis. However, these methods can result in underestimating peak $K_{dp}$ or negative values in convective regions, and fluctuated $K_{dp}$ in low rain rate regions. To resolve these problems, this study applied the $K_{dp}$ distribution method suggested by Lim et al. (2013) and evaluated by adopting new $K_{dp}$ to JPOLE and CSU algorithms. Data were obtained from the Mt. Biseul radar of MOLIT for two rainfall events in 2012. Results of evaluation showed improvement of the peak $K_{dp}$ and did not show fluctuation and negative $K_{dp}$ values. Also, in heavy rain (daily rainfall > 80 mm), accumulated daily rainfall using new $K_{dp}$ was closer to AWS observation data than that using legacy $K_{dp}$, but in light rain(daily rainfall < 80mm), improvement was insignificant, because $K_{dp}$ is used mostly in case of heavy rain rate of quantitative rainfall estimation algorithm.

Endowment of Traditionality to the New Style Taekwondo Uniform and a Proposal of Its Design Modification (신형 태권도 공인도복의 전통성 제언 및 디자인 수정 제안)

  • Choi, Yeon-Woo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.38 no.1
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    • pp.19-32
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    • 2014
  • The Taekwondo uniform has remained consistent since it was officially designed in a V-neck form in 1976. Taekwondo is a martial art that emphasizes social etiquette; therefore, it is necessary to dress in a uniform that reflects Korean traditions and ancient oriental philosophy. However, the current official uniform has limitations in endowing traditionality and many usability problems. Thus, recognizing the problems raised with the uniform, the Kukkiwon (World Taekwondo Headquarters) developed a new style official uniform in 2011. This study is to endow traditional meaning to a new style uniform and proposes some design modifications that can convey a more traditional adequacy. The development of the new official uniform began with a specific plan for change from the existing uniform, this study as subsequent work is significant in that its endowment of symbolism and modification proposal is for the actual execution and global dissemination of traditional Taekwondo culture. The results of this study are as follows. First, we can endow Korea's traditional historicity and symbolism to the new uniform in form and colors. All contents of the design (in which the front side is open, the top is adjusted rightward, the rear length is shorter than the front length, comfort provided by side vents, dual collars for children's uniforms, and a belt) are adapted from the Korean traditional costume. Consequently, historicity can be endowed to the uniform. It is also confirmed that the traditional oriental philosophy including heaven and earth (天地), Yin-Yang (陰陽), and Five Elements (五行) can be endowed in the use of colors. Second, in order to project deeper historicity and symbolism to the form of the new uniform, this study proposes design modifications based on the selection as an item of Simui (深衣), a type of traditional clothing that contains a high symbolism similar to the Taekwondo uniform. It proposes giving shape to the practice of manners, the righteous life, and the straightforward mind by modifying the design of the uniform in the fish belly part of the sleeves, collars, back stitches, and side seams.

A Study for Improving the Managerial and Technological Consultancy for Korean Medium Industries. (한국 중소기업을 위한 경영.기술 지도사업의 효율화 방안)

  • 장영기
    • Journal of the Korean Professional Engineers Association
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    • v.13 no.4
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    • pp.31-47
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    • 1980
  • Since medium and small manufacturing enterprises have , played a very important role not only in national economy but also in political and social relationships all of the countries in the world have paid favorable policies and programmes for protecting and promoting this sector. In Korea main ingredients of promoting policy for this sector consist of (1) encouragement to modernize facilities and rationalize operation (2) special priority in bank loan (3) promotion of industrial cooperatives (4) prevention of infringement by large industries. However, substantial investigation for problems incurred in medium industries has revealed that unless medium industries improve and raise their technological and managerial skillfulness for themselves all other measures are useless to solve the problems. This realization has induced all of the countries to render extension services on both of technology and management to assist and support their own effort for rationalization. Also in Korea during past 20 years many technical and managerial research institutes have rendered free consultancy services to medium industries by the support of government subsidy. Among them the joint extension services project performed by the Medium Industry Bank and UNDP during 1967 and 1975 might he listed as model case because of its broad and integrated activities and participation of foreign experts. We think many precepts should be :learned from the study of this project. Korean economy is expected to develop rapidly throughout coming'80 in spite of many obstacles, tut there is an apprehension that gap in of every facet between medium and large enterprises might he deepened and enlarged. To prevent the actualization of so-called dual structure of national economy and to promote stabilized medium industries with high added value productivity which are shown in well developed countries, consultancy assistance ana extension services should be strengthened much more than ever. Fortunately in 1978 legislation of "Medium and small industry promotion act" has paved the way for the systematic achivement of consultancy and extension services which shall be integrated by the government overall program. Under new framework thoughtfull accomplishment should be undertaken considering precious precepts obtained from past experience and failure. Special attention should be given to the technical liaison officer scheme, exclusive participation of only professional institutes, strict qualification and training for consultants for the future succsseful implementation.

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The Status and Challenges of Child Care Policy (보육정책의 실태와 과제)

  • Rho, Myung-Sook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.12
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    • pp.5738-5744
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    • 2012
  • The purposes of this study are to analyze the status of Child Care Policy, to discover the problems faced by child care policy and to provide better Child Care policies to reorient in the future. The following problems have been identified through the Child Care Policy Analysis of: (1) Due to '0 to 2 years' free Child Care, Dual-earner families was difficult to use Child Care facilities. (2) Low-income families with children over 36 months were excluded from receiving Care allowance. Child Care of publicity is difficult to secure. Because children using Child Care facilities use private type Child Care facilities than the national and public Child Care. Policy proposals to provide better Child Care policies are to increase the number of the national and public Child Care, to pay practical parenting allowance, to increase the number of high quality Infant Daycare Centers, to expand Part-time child care services and to support parent education and counseling program.

Adult Guardian's Misconduct in Japan and Its Implication for Korea (일본 성년후견인의 부정행위와 한국에서의 함의)

  • Jeon, Byeong-Joo;Kim, Keon-Ho
    • The Journal of the Korea Contents Association
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    • v.13 no.8
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    • pp.141-151
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    • 2013
  • The adult guardianship system takes effect from July 2013. At this point, just a month prior to the enforcement of the system, Korea should be prepared for specific countermeasures to implement the optimized system. Japan has high similarities in social and culture matters with Korea and is evaluated that the introduction background of adult guardianship system and overall operation system is similar to Korea's. As misconducts by adult guardians among the various problems occurred in Japan bring decreasing trust and delay the system settlement, proactive and posterior measures should be prepared for these problems. Therefore, in this study, misconducts by adult guardians occurred in the enforcement of adult guardianship system in Japan is to be examined and through these findings, several strategies were suggested to prevent misconducts in Korea which include the expansion of organization and manpower in family Court, dual supervision system and emergent appointment system etc.

Design and Implementation of Prototype model of inpant location tracker (유아위치 추적기의 프로트타입 모델 설계 및 구현에 관한 연구)

  • Choi, Sung-Jai
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.6
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    • pp.203-209
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    • 2017
  • Low birth rates and aging problems are raising a big issue in the worldwide. Recently, Korea also has no one to caring children who have low discernment and old ones who have Alzheimer's disease because of growing nuclear families and dual income furnitures. Therefore many serious crimes like kidnappings were occurred by people who have mental problems or bad intentions. Even though missing and ding alone are increasing together. The result of it, the needs of potable GPS system, to tracking for the olds and week ones, is highly growing nowadays. This paper introduce producing prototype tracker, looks like fashion accessories, which is using GPS, Zigbee and WiFi. It expects developing many accessory types of trackers effectively helps protect children and old ones from kidnappers at a low cost in this aging society.

Voice and Video Call Continuity for Enterprise Users (기업형 사용자들을 위한 음성/영상 서비스 이동성 제공 방안)

  • Jung, Chang-Yong;Kim, Hyeon-Soo;Moon, Jeong-Hyeon;Kim, Hee-Dong
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.99-103
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    • 2009
  • Recently, as wired and wireless communication services have rapidly developed and multimodal mobile devices which have various characteristics have widely spread, the need for new convergence services increases. The growing population of VoIP technologies and the high communication expense yield that the market of IP based telephony such as WiFi phone and IP phone is substituted for one of the conventional PSTN telephony. With the help of this trend, the wireline network operators desire to find a market in mobile networks. Therefore, they focus on Fixed Mobile Convergence (FMC) service as one of the key factors to accomplish this goal. FMC services are able to provide the mobility of voice services between circuit switched and packet switched networks. IP Multimedia Subsystem (IMS) based Voice Call Continuity (VCC) is one of the schemes to embody FMC services. As Application Server (AS) which has this VCC function provides seamless handover of services between heterogeneous networks, FMC subscribers can communicate seamlessly with others m WiFi domain and COMA domain using WiFi-COMA dual phone. Most of enterprises have already introduced IP network infrastructure and IP-PBX (Private Branch eXchange) for telephony. However, the problems of high communication cost and work inefficiency due to frequent outside jobs or business trips have remained. In order to solve these problems, demands for enterprise FMC services increase. In this paper, we introduce a new IP-PBX based VCC model that can provide seamless handover of voice services between WiFi and COMA networks for enterprise users and we investigate some interworking and security issues between Soft Switch (SSW) and IMS, or between IMSs. In addition, we introduce a new service that can provide the continuity of voice sessions as well as video sessions using Multimedia Session Continuity (MMSC) technology which has evolved from VCC. This service is expected to be one of the next-generation personalized services based on user's context.

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Recognition of Medical Doctors Employed to University Hospital on the Cooperative Medical System between Korean Traditional and Western Medicines (의과대학부속병원 의사들의 양.한방 협진에 대한 인식)

  • Lee, Eun-Joo;Park, Han-Sol;Lee, So-Young;Bae, Da-Jung;Lee, Tag-Gun;Shin, Hyeun-Kyoo
    • The Journal of Internal Korean Medicine
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    • v.33 no.3
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    • pp.298-305
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    • 2012
  • Objectives : This study was aimed to promote the cooperative system of Korean and Western medicine in the dual health care system through a survey of physicians on recognition, problems and solution of the cooperative system. Methods : The research took place at Dongguk University Hospital from May 25 to 27, 2009 with 44 professors, residents, and interns employed by the hospital. Results : Of total 44 surveyed doctors, positive and moderate responses on the cooperative system between Korean and Western medicines were 40.9% and 43.2%, respectively. They scored it positive (62.5%) and moderate (31.3%) based on their experiences. These results can be supposed to represent the environment for the interdisciplinary medicine. Even in the interdisciplinary hospital of Korean and Western medicine, 68.2% of responders had no experience of the cooperative medical system. Expected interdisciplinary efficient departments were ordered rehabilitation medicine, neurology and orthopedics and associated with musculoskeletal disorders, the most frequent diseases treated by Korean traditional medicine. Conclusions : Korean and Western medical doctors, as medical personnel, intellectual persons as well as specialists, need a recognition and attitude to understand and respect each others' medicine. However, both groups also realize there are many complicated issues in the treatment of patients. It is difficult to require a change of Western doctors' perceptions and attitude toward Korean traditional medicine only with results of a survey. For the efficient cooperative system in the medical field, Korean medical doctors will need to study and consider specific problems mentioned by Western medicine.