• 제목/요약/키워드: measurement interval

검색결과 689건 처리시간 0.029초

예열온도조건에 따른 알루미늄 합금 주조재의 응고특성에 관한 연구 (A Study on Solidification Characteristics of Aluminum Alloy Casting Material by Pre-heated Temperature Conditions)

  • 윤천한;윤희성;오율권
    • 한국안전학회지
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    • 제27권4호
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    • pp.7-12
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    • 2012
  • In this study, the solidification characteristics inside the AC7A casting material was analyzed using the numerical analysis method and was verified using the experimental method by the pre-heated temperature conditions of metal casting device. For the numerical analysis, "COMSOL Multiphysics", the commercial code based on the finite element analysis(FEA), was used in order to predict the thermal deformation of the AC7A casting material including temperature, displacement and stress distribution. Also, in order to verify the results calculated by the numerical analysis, the experiment for temperature measurement inside the AC7A casting material was performed using the K-type thermocouple under the same condition of numerical analysis method. In the numerical results, thermal deformation inside AC7A casting material was well-suited for manufacturing products when the pre-heated temperatures of the metal casting device was $250^{\circ}C$. When the results of the temperature distribution were experimentally measured and were compared with those of the numerical result, it appeared that there was some temperature difference because of the latent heat by phase change heat transfer. However, the result of cooling temperature and patterns were almost similar except for the latent heat interval. The solidification characteristics was closely related to the temperature difference between the surface and inside of the casting.

알코올 의존 환자에서 한국어판 알코올 충동 척도(Korean Alcohol Urge Questionnaire, AUQ-K)의 신뢰도와 타당도 연구 (The Study on Reliability and Validity of Korean Alcohol Urge Questionnaire(AUQ-K) for Alcohol Dependence)

  • 김철민;김성곤;김민정;김호찬;오광욱;김효정;김세훈;이덕기;변원탄;강철중
    • 생물정신의학
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    • 제15권3호
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    • pp.204-210
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    • 2008
  • Objectives : The Alcohol Urge Questionnaire(AUQ) has been used in alcohol dependence treatment and research. The goal of this study is to develop of the Korean Alcohol Urge Questionnaire(AUQ-K). Methods : To examine the AUQ-K's psychometric properties, responses from 104 patients admitted in alcohol dependence treatment facility were investigated. Results : The internal consistency of the 8-item AUQ-K, measured by coefficient ${\alpha}$, was high(Cronbach's ${\alpha}$=0.78). AUQ-K scores showed significant correlation when the retest interval was 1 day(p<0.01). The AUQ-K's validity was investigated using correlational analyses with two other craving scales[the Obsessive Compulsive Drinking Scale(OCDS) and the Visual Analogue Scale(VAS)]. The high correlations were obtained between total AUQ-K scores and total OCDS scores, and between total AUQ-K scores and the VAS scores(p<0.01, respectively). Conclusion : The AUQ-K is a reliable and valid short scale for measurement of self-reported alcohol craving. This scale may offer significant advantages over existing single-item measures of alcohol craving in the fields of alcohol dependence treatment and research.

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A Simulation Study of a Chopping System for Extracting a Pulsed Beam from a Cyclotron

  • 김재홍;홍성광;김미정;김성준;김명진;김도균;윤종철;김종원
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.537-537
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    • 2013
  • Cyclotron-accelerated ion beams are used for various researches, such as nuclear physics, nuclear chemistry, biotechnology, and material sciences including radio-isotope production. Recently considerable applications are asked to the cyclotron development undertaken to meet user requirements of various ions'energies, intensities, and their pulsed beams. For instance, a cocktail beam acceleration technique rapidly changing the ion species and energies was developed to irradiating integrated circuit chips. Also a chopping system in a cyclotron injection line is considered for producing a pulsed ion beam with a relatively long period compared with that generated by the resonance frequency. For the research in neutron time-of-flight measurement, a single-pulsed beam with a repetition interval of the order of mili-seconds or longer is necessary to have a good resolution and to remove background events. In this paper a feasibility of pulsed beam with an external ion source is simulated by adopting a combination system of a chopper accompanying with a bunching stage in the injection line and an additional chopper after the exit of the cyclotron in order to produce beam pulses with a range of $1{\mu}s{\sim}1ms$ periods from a resonance RF cycle. The pulseperiod will be adjusted by chopping the number of beam bunches from the injected pulses in the injection line. However, the longer pulses will have reduced number of beam pulses and sacrificed beam currents. Because the beam users need an intense single pulsed beam, a careful tuning of the acceleration phase and a high-intense external ion source are necessary to achieve an intense single-pulsed beam from the cyclotron. It is essential to strictly match the acceleration phase of injected beams in the central region of the cyclotron to improve its efficiency. An effect of space charge at each pulse from the ion source will be also considered.

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전자궁적출술후 통증자가조절장치 사용에 따른 통증점수 비교 (Comparison of Quality of Pain Using Patient-Controlled Analgesia (PCA) after Total Abdominal Hysterectomy (TAH))

  • 이정구;박석;정정길
    • The Korean Journal of Pain
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    • 제11권2호
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    • pp.253-257
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    • 1998
  • Background: The purpose of this study was to examine the extent and evaluation of pain after total abdominal hysterectomy (TAH) and to establish correlation between three types of pain; pain at rest, pain with movement and pain with coughing (maximum pain). Methods: The present study compared quality of pain during pain management in 48 patients undergoing TAH. Patients received i.v. meperidine as loading dose in the recovery room and PCA with nalbuphine 90 mg, ketorolac 180 mg, buprenorphine 0.9 mg, droperidol 5 mg, plasma solution A 28 ml for 3 days. The PCA device used was the Baxter infusor$^{(R)}$ (PCA module PC-19-55, 0.5 ml/hr basal rate, 15 minute lockout interval). Patients were then interviewed on Operative Day (OPD), Postoperative Day 1, 2, and 3 (POD 1, 2 and 3) to assess their pain on a visual analogue scale (VAS) of 0 (none) to 10 (worst imaginable). Results: The mean pain score at rest was 2.0 on OPD and decreased to 0.7 on POD 3. The mean pain score with movement was 3.2 on OPD and decreased to 1.6 on POD 3. The mean pain score with coughing was 4.2 on OPD and decreased to 2.2 on POD 3. Conclusions: Patients' experience of three types of postoperative pain emphasizes the need for more effective pain management.

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Precision Orbit Determination of the SAC-C Satellite Using the GPS Dual Frequency Measurement

  • Yoon, Jae-Cheol;Im, Jeong-Heum;Moon, Hong-Youl;Lee, Sang-Ryool;Lee, Byoung-Sun
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2003년도 한국우주과학회보 제12권2호
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    • pp.48-48
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    • 2003
  • A precision orbit determination (POD) system of low Earth orbiter using the GPS dual frequency measurements has been developed. It is an option of KOMPSAT-2 POD process system. In this research, the orbit determination using the real dual frequency carrier phase measurements of the SAC-C satellite was conducted to verify KOMPSAT-2 POD system reliability. The SAC-C satellite is an international cooperative mission between NASA, the Argentine Commission on Space Activities (CONAE), Centre National d'Etudes Spatiales (CNES or the French Space Agency), Instituto Nacional De Pesquisas Espaciais (Brazilian Space Agency), Danish Space Research Institute, and Agenzia Spaziale Italiana (Italian Space Agency). The SAC-C was launched at November 21, 2000. The altitude of SAC-C is 702 km and it carries a TurboRogue III GPS and four high gain antennas developed by the JPL. The receiver is able to generate the dual frequency code and carrier phase data. Double-differenced carrier phase measurements were formed using 25 IGS stations. The data were sampled at 30 seconds interval. Fully dynamic approach was adopted for POD. The POD results were compared with those of JPL using GOA n software. The comparison verifies that deci-meter level 3D position accuracy of low Earth orbiting satellite could be achieved. The POD system has been developed successfully.

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경추의 전신조정 관절치료가 좌우 관절가동범위에 미치는 영향 (The effect of left & right range of motion according to general coordination manipulation treatment on cervical)

  • 김형수;문상은;채정병;김은영
    • 대한물리치료과학회지
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    • 제10권2호
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    • pp.112-122
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    • 2003
  • The purpose of this study is to search effect that GCM joint treatment gets to right and left range of motion of neck, lumbar, trunk and anke joint. Estimated body deformity using GCM body type assesment chart then measured range of motion of each region. After control group did as act freely after do experiment premeasurement control group did postmeasurement. Each region was measured by measurer who each subject person differs. Experimental group did GCM joint treatment and all measurements each region by measurer who each subject person differs three times measured. When measure with each measurement, measured after leave and walk time interval for 10 minutes. For the analysis of the resulr of experiment the results is change amount comparison increased to keep in mind except ankle joint's dorsiflexion before experiment of experimental group and control group(P<.05). Before an experiment and after an experiment of experimental group, differed to keep in mind in right and left comparison of neck rotation, dorsiflexion, plantaflexin of ankle joint in change amount comparison(P<.05). Neck lateral flexion appears and displayed significantly level right and left difference than rotation after experiment of experimental group(P<.05). Because dorsiflexion, plantefleaion of ankle joint became similar right and left significantly difference did not appear(P<.05).

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XAD 수지에 의한 친수성 및 소수성 수용성 유기탄소의 특성조사 (Study on Characterization of Hydrophilic and Hydrophobic Fractions of Water-soluble Organic Carbon with a XAD Resin)

  • 정재욱;김자현;박승식;문광주;이석조
    • 한국대기환경학회지
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    • 제27권3호
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    • pp.337-346
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    • 2011
  • 24-hr integrated measurements of water-soluble organic carbon (WSOC) in PM2.5 were made between May 5 and September 25, 2010, on a six-day interval basis, at the Metropolitan Area Air Pollution Monitoring Supersite. A macro-porous XAD7HP resin was used to separate hydrophilic and hydrophobic WSOC. Compounds that penetrate the XAD7HP column are referred to hydrophilic WSOC, while those retained by the column are defined as hydrophobic WSOC. Laboratory calibrations using organic standards suggest that hydrophilic WSOC includes lowmolecular aliphatic dicarboxylic acids and carbonyls with less than 4 or 5 carbons, amines, and saccharides. While the hydrophobic WSOC is composed of compounds of aliphatic dicarboxylic acids with carbon numbers larger than 4~5, phenols, aromatic acids, cyclic acid, and humic-like Suwannee River fulvic acid. Over the entire study period, total WSOC accounted for on average 48% of OC, ranging from 32 to 65%, and hydrophilic WSOC accounted for on average 30.5% (9.3~66.7%) of the total WSOC. Based on the previous results, our measurement result suggests that significant amounts of hydrophobic WSOC during the study period were probably from primary combustion sources. However, on June 9 when 1-hr highest ozone concentration of 130 ppb was observed, WSOC to OC was 0.61, driven by increases in the hydrophilic WSOC. This result also suggests that processes, such as secondary organic aerosol formation, produce significant levels of hydrophilic WSOC compounds that add substantially to the fine particle fraction of the organic aerosol.

Surgical Management of Massive Cerebral Infarction

  • Huh, Jun-Suk;Shin, Hyung-Shik;Shin, Jun-Jae;Kim, Tae-Hong;Hwang, Yong-Soon;Park, Sang-Keun
    • Journal of Korean Neurosurgical Society
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    • 제42권4호
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    • pp.331-336
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    • 2007
  • Objective : The aim of this study was to analyze the treatment results and prognostic factors in patients with massive cerebral infarction who underwent decompressive craniectomy. Methods : From January 2000 to December 2005, we performed decompressive craniectomy in 24 patients with massive cerebral infarction. We retrospectively reviewed the medical records, radiological findings, initial clinical assessment using the Glasgow Coma Scale, serial computerized tomography (CT) with measurement of midline and septum pellucidum shift, and cerebral infarction territories. Patients were evaluated based on the following factors : the pre- and post-operative midline shifting on CT scan, infarction area or its dominancy, consciousness level, pupillary light reflex and Glasgow Outcome Scale. Results : All 24 patients (11 men, 13 women; mean age, 63 years; right middle cerebral artery (MCA) territory, 17 patients; left MCA territory, 7 patients) were treated with large decompressive craniectomy and duroplasty. The average time interval between the onset of symptoms and surgical decompression was 2.5 days. The mean Glasgow Coma Scale was 12.4 on admission and 8.3 preoperatively. Of the 24 surgically treated patients, the good outcome group (Group 2 : GOS 4-5) comprised 9 cases and the poor outcome group (Group1 : GOS 1-3) comprised 15 cases. Conclusion : We consider decompressive craniectomy for large hemispheric infarction as a life-saving procedure. Good preoperative GCS, late clinical deterioration, small size of the infarction area, absence of anisocoria, and preoperative midline shift less than 11mm were considered to be positive predictors of good outcome. Careful patient selection based on the above-mentioned factors and early operation may improve the functional outcome of surgical management for large hemispheric infarction.

치근형 골내 임플란트의 초기 1년간 치조골 소실 및 골 밀도 변화에 관한 연구 (ALVEOLAR BONE LOSS & BONE DENSITY CHANCES DURING THE FIRST YEAR A COMPARATIVE STUDY ON FOUR TYPES OF ROOT-FORM ENDOSSEOUS DENTAL IMPLANT SYSTEMS)

  • 정영철;한종현;이근우
    • 대한치과보철학회지
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    • 제32권3호
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    • pp.455-469
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    • 1994
  • Regular radiographic examination has been considered an essential diagnositic method for osseointegrated dental implantation. This study investigated marginal bone loss through the measurement on periapical radiographs and changes in bone density through digital subtraction image radiographic method around 88 endoseous root-form dental implants in 43 human subjects. Four types of endosseous dental implants were investigated : Standard series, Mini series and Hex-lock system of Steri-Oss Dental implant system, and $Br{\aa}nemark$-type implant from 3i dental implant system, in a 3 month interval for a total period of 12 months. The results were as follows : 1. Rapid bone loss occurred in the first 3 months in all 4 groups, and the bone level stabilized at the first thread of the implant fixtures. Amount of bone loss for 12 months showed correlation with the length of the polished neck portion. 2. Most of the implant systems showed resorption of alveolar bone up to the polished neck portion although a long polished neck could delay the resolution. 3. Alveolar bone loss apical to the polished neck portion stabilized at the first thread of the fixtures with no correlation to either the time of exposure of the polished neck or types of implant systems. 4. No changes in bone density around the implant threads were observed throughout the experimental period. Bone density decreased at the marginal bone, and increased at the newly-formed alveolar crest. These results indicate that most of the alveolar bone loss occur within the first 12 months after installation of endosseous root-form dental implants resulting in the exposure of polished neck portions, and the bone level stabilizes thereafter at the first thread portions of the implant fixtures. The experimental period of 12 months seems insufficient for observing changes in bone density, and a long-term observation should be needed.

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차세대 이동통신 패킷 수송망에서 서비스 품질을 고려한 효율적인 대역폭 재할당 기법 (An Efficient QoS-Aware Bandwidth Re-Provisioning Scheme in a Next Generation Wireless Packet Transport Network)

  • 박재성
    • 한국통신학회논문지
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    • 제31권1A호
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    • pp.30-37
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    • 2006
  • 본 논문에서는 차세대 이동통신 수송망에서 트래픽 클래스별 서비스 품질 요구 사항을 고려한 효율적인 대역폭 재할당 기법을 제안한다. 제안 기법은 유선망 트래픽 클래스를 실시간 클래스와 비시실시간 클래스로 구분하여 무선망 계층에서 정의된 서비스 품질 클래스를 유선망 트래픽 클래스로 매핑시킨 후 실시간 트래픽 클래스가 비실시간 트래픽 클래스의 유휴 자원을 동적으로 사용하도록 한다. 제안 기법은 운영자가 지정한 패킷 손실율과 Auto-Regressive(AR) 시계열 모델을 이용하여 주기적으로 비실시간 트래픽 클래스의 향후 필요 대역폭을 예측하며 유휴 대역폭이 발생하는 경우에만 이를 실시간 트래픽 클래스에 동적으로 할당함으로써 비실시간 트래픽 클래스의 패킷 손실율을 보장함과 동시에 시스템의 대역폭 이용율을 향상시킨다. 본 논문에서는 실제 측정된 인터넷 트래픽을 비실시간 트래픽 클래스로 이용하여 제안 기법은 링크 대역폭의 효율을 증가시켜 실시간 트래픽의 수용량을 증가시킴과 동시에 모든 시 구간에서 비실시간 트래픽 클래스에 원하는 패킷 손실율을 보장할 수 있음을 검증하였다.