• Title/Summary/Keyword: Improving design

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An Experimental Study for Improving the Durability of Concrete Bridge Decks (교량 바닥판 콘크리트의 내구성 증진을 위한 실험적 연구)

  • Suh, Jin-Won;Rhee, Ji-Young;Ku, Bon-Sung;Shin, Do-Chul
    • Journal of the Korea Concrete Institute
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    • v.19 no.4
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    • pp.393-399
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    • 2007
  • Concrete bridge decks are directly exposed to the severe environmental conditions such as rain water and deicing chemicals resulting in the freeze-thaw action and the rebar corrosion during their service lift. These deteriorations of bridge decks shorten the service lift and consequently they are the major concerns of the maintenance. The high performance concrete (HPC) deck is proposed as the alternative to minimize the deterioration problems. To develop more durable concrete deck, the performance characteristic tests of HPC mixtures were carried out. In this study, 4 different concrete mixtures were used varying the mineral admixtures as the cement replacement; ordinary portland cement (OPC), 20% fly ash (FA),20% fly ash with 4% silica fume (FS), and 40% ground granulated blast-furnace slag (BS). The design compressive strengths of HPC specimens were 27 MPa and 35 MPa, respectively. The results showed that the compressive strength of concrete did not much affect the durability of concrete. HPC with fly ash and silica lune (FS) were turned out to have the good durability and crack resistance.

A Convergence Study on the Effect of Self-directed Practice based Peer-tutoring on Performance, Confidence and Self-efficacy of Core Nursing Skills in Nursing Students (동료 교수학습 기반 자율실습이 핵심기본간호술 숙련도, 수행자신감 및 자아효능감에 미치는 효과에 관한 융합연구)

  • Koo, Heesun
    • Journal of the Korea Convergence Society
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    • v.10 no.12
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    • pp.453-463
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    • 2019
  • The purpose of study was the non-equivalent control group pretest-posttest design to test the effect of self-directed nursing practice based peer-tutoring of same sophomore, on the level of confidence, performance and self-efficacy of core nursing skills in nursing students. The subjects were 68 nursing students in K City from May 1th to June 12th in 2019. The participants were shared into the peer tutoring practice group (experimental group, n=34) and the lecturer guided practice group (control group, n=34). The results of study, the experimental group scored significantly higher on the foley catheterization performance (t=11.60, p<.001), confidence (t=4.123, p<.001) and wearing protection equipment performance (t=5.91, p<.001), confidence (t=4.24, p<.001) and enema performance (t=2.82, p=.008), confidence (t=2.09, p=.044) and self-efficacy (t=4.52, p<.001) than control group. Therefore, the results justified that self-directed nursing practice based peer-tutoring could be effective in improving the performance, confidence and self-efficacy of core nursing skills in nursing students. Based on this, I suggest the study that examines the effects of peer-tutoring by applying it to various majors.

Convergence Factors Influencing Perceived Health Status, Health Promotion Behavior and Anxiety of Dementia Development in the Elderly Participation in Local Expos on Health-related Quality of Life (지역박람회 참여 노인의 지각된 건강상태, 건강증진행위 및 치매발병 불안이 건강관련 삶의 질에 미치는 융합적 영향요인)

  • Song, Hwan;Kim, Hye-Sook
    • Journal of the Korea Convergence Society
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    • v.11 no.7
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    • pp.41-49
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    • 2020
  • This study is a descriptive research study for the elderly who participated in the community's fair to identify the factors of the convergent impact of perceived health conditions, health promotion activities and dementia anxiety on the quality of health-related life. The research subjects were surveyed on 435 senior citizens aged 65 or older among the participants in the 2019 Regional Exposition, and analyzed using statistics, ANOVA, Pearson's correlation and multiple regression analysis using the SPSS 21.0 program. According to the study, the quality of life related to health affects 53.0% of the convergence factors such as perceived health conditions, health promotion activities, monthly income, and economic conditions. Therefore, various community events or programs that can lead to the reduction of dementia anxiety and the improvement of health promotion activities will have to be developed to motivate or make promotional efforts for senior citizens to participate in community events or programs, which will enable senior citizens to build social networks through the participation of various programs in the community, thereby improving health promotion activities and reducing dementia anxiety, which will improve the quality of life for senior citizens.

Design and Analysis of Intelligent AMC Scheme with Relay Protocols in LTE-Advanced System (LTE-Advanced 시스템에서 릴레이 프로토콜을 적용한 지능형 AMC 기법의 설계 및 분석)

  • Malik, Saransh;Kim, Bora;Moon, Sangmi;Kim, Daejin;Hwang, Intae
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.12
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    • pp.10-19
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    • 2012
  • In this paper, we propose an Adaptive Modulation and Coding (AMC) scheme using relay protocols generally known as Relay Node (RN). The AMC scheme is used for improving the throughput and a reliability of a communication system, because of the nature of different modulation and coding schemes. We analyze the performance of relay protocols with the AMC scheme and observed that relay protocols with the AMC scheme is capable of providing better average throughput at a lower Signal to Noise Ratio (SNR) level as compared to the conventional scheme with no AMC. We perform Monte Carlo simulations with Long Term Evolution-Advanced (LTE-A) parameters to prove the performance comparison of adaptive Modulation and Coding Scheme (MCS) relay protocols with the non-adaptive MCS relay protocols. The simulation results of the proposed system with adaptive MCS prove that among the Amplify-and-Forward (AF), Decode-and-Forward (DF) and DeModulate-and-Forward (DMF), the DMF protocol performs best at a lower SNR value and also provides better average throughput.

A Study and Design of Beam Scanning Array Antenna using IR-UWB (IR-UWB를 이용한 빔 스캐닝 배열 안테나 설계 및 연구)

  • Kim, Keun-Yong;Kang, Eun-Kyun;Kim, Jin-Woo;Ra, Keuk-Whan
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.3
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    • pp.194-201
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    • 2014
  • This paper is able to be solved by improving degradation in multi-path environment by adjust beam pattern angle through modifying pulse phase of each antennas by using TRM (Transmitter Receiver Module). Beam Scanning Array Antenna, which is transmitter/receiver that improves degradation in multi-path environment without any signal distortion, is designed and manufactured. Beam Scanning Array Antenna should be able to send/receive signal at the antenna's longitudinal part without distortion and should not influences other systems. Also, it should include target detecting ability by beam steering.Dispersion characteristic of Beam Scanning Antenna, which is designed, is analysed by using fidelity, and steering and radar resolution performance is verified by using $1cm{\times}1cm$ sized target. To manufacture Beam Scanning Array Antenna, control board and GUI, which is able to control Vivaldi Antenna for IR-UWB, Tri-Band Wilkinson power divider, and TRM (Transmitter Receiver Module), is designed. Throughout this research, developed Beam Scanning UWB Array Antenna system is adoptable for radar application field. and time domain analysis techniques by using network analyser made the antenna characteristics analysis for setting up antenna more accurate. In addition, it makes beam width checking without difficulties.

Design of a Low Phase Noise Vt-DRO Based on Improvement of Dielectric Resonator Coupling Structure (유전체 공진기 결합 구조 개선을 통한 저위상 잡음 전압 제어 유전체 공진기 발진기 설계)

  • Son, Beom-Ik;Jeong, Hae-Chang;Lee, Seok-Jeong;Yeom, Kyung-Whan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.6
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    • pp.691-699
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    • 2012
  • In this paper, we present a Vt-DRO with a low phase noise, which is achieved by improving the coupling structure between the dielectric resonator and microstrip line. The Vt-DRO is a closed-loop type and is composed of 3 blocks; dielectric resonator, phase shifter, and amplifier. We propose a mathematical estimation method of phase noise, using the group delay of the resonator. By modifying the coupling structure between the dielectric resonator and microstrip line, we achieved a group delay of 53 nsec. For convenience of measurement, wafer probes were inserted at each stage to measure the S-parameters of each block. The measured S-parameter of the Vt-DRO satisfies the open-loop oscillation condition. The Vt-DRO was implemented by connecting the input and output of the designed open-loop to form a closed-loop. As a result, the phase noise of the Vt-DRO was measured as -132.7 dBc/Hz(@ 100 kHz offset frequency), which approximates the predicted result at the center frequency of 5.3 GHz. The tuning-range of the Vt-DRO is about 5 MHz for tuning voltage of 0~10 V and the power is 4.5 dBm. PFTN-FOM is -31 dBm.

The Effects of Muscle Relaxation to The Rheumatoid Arthritis Patients' Adaptation (류마티스성 관절염 환자의 적응에 미치는 근이완술에 효과)

  • Jung, Hyan-Mi
    • Journal of muscle and joint health
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    • v.1 no.1
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    • pp.31-47
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    • 1994
  • The purposes of this research are to examine the effects of muscle relaxation to the rheumatoid arthritis patients' physiological, psychological, and social adaptation, and to verify that the technique Is an effective tool for improving the patients' adaptation. This research utilized a qusi-experimental design that compares the pre-experiment measures and the post-experiment measures. The subjects of this study were 37 out-patients who were diagnosed for rheumatoid arthritis in P university hospital and K clinic between September 12, 1993 and November 30, 1993. The experimental group consisted of patients treated on Monday, Wednesday and Friday. The control group consisted of patients treated on Tuesday, Thursday and Saturday The pre-experimental survey utilized the following tools. The physiological adaptation was measured by a graphic rating scale for pain and activity of daily living. The psychological adaptation was measured by Zung's depression scale and Rosenberg's self-esteem scale : and the social adaptation was measured by Derogatis' psychosocial adjustment scale. The experimental group received muscle relaxation treatment for 15 minutes per day for the period of 2 weeks, the control group received no treatment and had quiet time. The post-experiment measurement was carried out similar to the pre-experiment survey, SPSS $PC^+$ is used to analyze the collected data. The reliabilities of the measurement tools were examined by Cronbach's ${\alpha}$ coefficients. The homogeneities between the experimental and control groups were tested by t-test and chi-square test, hypotheses were tested by t-test. This research found that the general characteristics between the groups were statistically homogenious. The physiological, psychological, and social adaptation between the groups in the pre-experimental survey were also statistically homogenious. The results of this research can be summarized as follows : 1. Concerning the Physiological adaptation, the experimental group showed a statistically lower pain score than the control group. Thus, muscle relaxation was effective to relieve the pain of rheumatoid arthritis patients (t=-2.95, p=.006). 2. Concerning the psychological adaptation, the experimental group showed a statistically lower depression score than the control group. Thus, muscle relaxation was effective to reduce the patient's depression(t=-4.00, p=.001). 3. Concerning social adaptation, the experimental group showed a statistically higher score for the health maintenance and disease control than the control groups. Thus, muscle relaxation was effective for the health maintenance and disease control (t=2.09, p=.004). This research showed that the muscle relaxation is a nursing intervention that can promote the physiological, psychological and social adaptation of the rheumatoid arthritis patients in terms of short-term and cognitive changes. However, more fundomental changes in behavior and long-term physiology could not be found through such a short-term relaxation treatment.

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Research Methods on Scalp and Hair Management through the Pass of Time (시대적 흐름에 따른 두피와 모발관리에 대한 연구방법)

  • Kim Myung-Joo;Baek Seung-Hwa
    • Journal of Society of Preventive Korean Medicine
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    • v.7 no.1
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    • pp.123-132
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    • 2003
  • It is considered to be important to create aesthetically beautiful style through the change of external shape, however for the hair stylists, whose beauty expression is through hair, the role of hair doctor is becoming even more important with focus to improve the hair healthiness. Hair clinic is management of hair and scalp. It is the management process of preventing damages, while improving and cultivating healthy and shiny hair. The current concept in hair management is moving from simple hair styling to emphasis at hair management. As far as hair management is concerned, it usually includes treatment tools such as shampoo, conditioner, hair treatment and scalp scaling system, which is used for diagnosis of hair condition in order to treat the scalp. As the interest of hair healthiness becoming more wide spread, so does the breadth of clinic menu. The wide choice is to fulfill the profound desire of people, whose demands are simply to have variety in their choice. This is resulting in faucets of new value-added and differentiated products. The values that make-up the hair styles consist of mainly design (trend, preference), function(styling, management convenience) and clinic(hair quality improvement, damage repair). Shampoo and conditioner have gone beyond their original function of cleansing to providing combinational functions of treatment, to care and remedy, and advanced massage effectiveness. These are, to name a few that seem to go beyond their original function to satisfy the mental healthiness in people, the King Kong shampoo of shampooings in forward-backward manner, 5-minute shampoo massage that applies sports and relaxation massage, scalp acupunctural message and aural(ear) massage. More and more people are complaining about the damaged hair and hair loss problems due to perms, dyeing and bleaching of hair, in addition to natural scalp and hair damaging factors. Such complaints have stimulated many beauty products and various hair treatment systems being introduced with focus to provide nutrition and prevent damages to scalp and hair. As the living standards improve and the desire of people is to pursue differentiated lives, their demand also increases in hair styling products to fulfill the needs of healthy and aesthetical aspects of their lives.

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A Numerical Study for the Atrium Smoke Control by Fire Shutter and Evacuation (방화셔터를 이용한 아트리움 제연과 피난안전에 관한 수치해석 연구)

  • Jeon, Heung-Kyun;Choi, Young-Sang;Choo, Hong-Lok
    • Fire Science and Engineering
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    • v.24 no.5
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    • pp.50-59
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    • 2010
  • Four fire scenarios, as the cases of fire sizes of 2 MW and 5 MW, and no installation and activation of atrium fire shutter for dormitory building of Daegu 'D college', were developed and fire simulations were run using FDS (ver. 5.5.0) and Pathfinder 2009 programs. By assessing fire and evacuation, the effects of atrium fire shutter and vents on the smoke control of atrium were evaluated and this study also analyzed fire hazard and egress safety for occupants in the dormitory. Fire shutter's preventing smoke transport around atrium was much effective, but smoke layer descended down the design limit of smoke height and kept about 2 m height from the atrium floor in all cases because flow rate through vents was not enough. For the case of 5 MW fire and no fire shutter, fire hazard was higher due to visibility than temperature and allowable egress time to stairwell was short less than 5 seconds for the occupants on the floors of 4F to 7F. For total occupants, egress time out of main doorway was calculated about 136 seconds. It is sure that additional systems improving the performance of smoke control need to be installed for more safe evacuation.

Methodologic Lessons Learned from Multicenter, Randomized, Controlled Clinical Trial of Acupuncture for Hot Flashes in Peri- and Postmenopausal Women (갱년 및 폐경 후 여성의 안면홍조에 대한 침 치료 다기관 임상연구 : 수행보고 및 방법론적 교훈)

  • Kim, Kun-Hyung;Kim, Dong-Il;Hwang, Deok-Sang;Lee, Jin-Moo;Kim, Hyung-Jun;Yoon, Hyun-Min;Jung, Hee-Jung;Kang, Kyung-Won;Lee, Myeong-Soo;Choi, Sun-Mi
    • The Journal of Korean Obstetrics and Gynecology
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    • v.23 no.1
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    • pp.42-52
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    • 2010
  • Purpose: This report aims to administer methodologic issues around recently conducted multicenter study for evaluating the effects of acupuncture on menopusal hot flashes and discuss practical issues for further implementation of acupuncture clinical trial for hot flashes. Methods: Study process were mentioned, and issues related to avoiding risk of bias, designing appropriate control group, optimal outcome measurement, potential different effects of menopausal status on study outcomes, and suggestions for developing future clinical trials are discussed. Results: Shortcomings of our multicenter study include lack of allocation concealment and assessor blinding, subjective outcome measurement, short-term follow-up, and fixed acupuncture regimen despite pragmatic purpose of this study. Improving trial design, using objective or validated outcomes, assessing long-term effects of acupuncture, and individualizing acupuncture regimen are needed in future clinical trials. Conclusion: We expect these practical discussions to enable researchers to plan and develop future well-designed clinical trials for evaluating the effects of acupuncture on hot flashes or other women's health issues.