• 제목/요약/키워드: PC/A ratio

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Hot Wall Epitaxy(HWE)법에 의한 MnAl2S4 단결정 박막 성장과 광전도 특성 (Growth and optical conductivity properties for MnAl2S4 single crystal thin film by hot wall epitaxy method)

  • 유상하;이기정;홍광준;문종대
    • 한국결정성장학회지
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    • 제24권6호
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    • pp.229-236
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    • 2014
  • 수평 전기로에서 $MnAl_2S_4$ 다결정을 합성하여 HWE(Hot Wall Epitaxy)방법으로 $MnAl_2S_4$ 단결정 박막을 반절연성 GaAs(100)기판에 성장시켰다. $MnAl_2S_4$ 단결정 박막의 성장 조건은 증발원의 온도 $630^{\circ}C$, 기판의 온도 $410^{\circ}C$였고 성장 속도는 $0.5{\mu}m/hr$였다. 이때 $MnAl_2S_4$ 단결정 박막의 결정성의 조사에서 이중결정 X-선 요동곡선(DCRC)의 반폭치(FWHM)도 132 arcsec로 가장 작아 최적 성장 조건임을 알 수 있었다. $MnAl_2S_4$/SI(Semi-Insulated) GaAs(100) 단결정 박막의 광흡수를 293 K에서 10 K까지 측정하였다. 광흡수 스펙트럼으로부터 band gap $E_g(T)$는 Varshni 공식에 따라 계산한 결과 $E_g(T)=3.7920eV-(5.2729{\times}10^{-4}eV/K)T^2/(T+786K)$였다. $MnAl_2S_4$ 단결정 박막의 응용소자인 photocell로 사용할 수 있는 pc/dc 값이 가장 큰 광전도셀은 S 증기분위기에서 열처리한 셀로 $1.10{\times}10^7$이었으며, 광전도 셀의 감도(sensitivity)도 S 증기분위기에서 열처리한 셀이 0.93로 가장 좋았다. 또한 최대 허용소비전력(MAPD)값도 S 증기분위기에서 열처리한 셀이 316 mW로 가장 좋았으며, S 증기분위기에서 열처리한 셀의 응답시간은 오름시간 14.8 ms, 내림시간 12.1 ms로 가장 빠르게 나타나, $MnAl_2S_4$ 단결정 박막을 S 분위기에서 $290^{\circ}C$로 30분 열처리한 photocell이 상용화가 가능할 것으로 여겨진다.

온경탕이 족부냉증에 미치는 영향에 대한 다기관 이중맹검 무작위 대조군 연구 (Effect of Onkyung-tang on Cold Hypersensitivity on Feet: A Multi-center Double-blind Randomized Controlled Trial)

  • 권나연;유준상;김형준;이동녕
    • 대한한방부인과학회지
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    • 제33권3호
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    • pp.149-174
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    • 2020
  • Objectives: This study was aimed to figure out the effect of Onkyung-tang (OKT) on cold hypersensitivity on feet in female patients. Methods: This study was designed to implement multi-center randomized clinical trial in three korean medical hospitals. The female patients who were enrolled in this study were 112 women who suffered from cold hypersensitivity on feet. They were randomly allocated into OKT group or control group in 1:1 ratio. The primary outcome was change in score of visual analogue scale of hypersensitivity on feet, and the secondary outcomes were thermometer of LU4, PC8, ST32, LR3, visual analogue scale of hypersensitivity on hands, result of cold stress test, and score of World Health Organization Quality of Life-BREF. Results: In both group, the VAS of hypersensitivity on feet and hands was decreased while taking the medicine, and the effect of decreasing the VAS continues for the 4 weeks after the end of medication (p<0.001, 0.003, 0.001). In OKT group, the body temperature difference in lower extremity (ST32-LR3) was steadily decreased at every visit and it was statistically significant(p=0.003, <0.001). On the other hand, in control group, the body temperature difference in lower extremity was decreased only while taking the medicine (p<0.001). Conclusions: OKT significantly reduced discomfort coldness on feet in patients, and the effect of treatment was maintained at least for four weeks after medication.

쑥뜸치료가 암환자의 심박변이도에 미치는 영향 (The Effects of Moxibustion on Heart Rate Variability in Cancer Patients)

  • 김옥희;최정은;윤정원;유화승
    • 대한암한의학회지
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    • 제16권1호
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    • pp.15-31
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    • 2011
  • Objective : The study aims to investigate the effect of moxibustion treatments on autonomic nervous system function of cancer patients through the evaluation of heart rate variability (HRV) biofeedback testing. Materials and Methods : Six cancer patients from inpatient care unit of Dunsan Oriental Hospital, Daejeon University were given three moxibustion treatment sessions every other day over one week period on five Oriental Medicine meridian points CV4, CV6, CV12, KD1, and PC8. HRV biofeedback was conducted before and after each treatment sessions. Three areas of analyses were done from the test conducted; Time Domain Analysis, Frequency Domain Analysis and Autonomic Nervous System (ANS) balance analysis. Results : Time Domain Analysis has shown increased Standard Deviation of all Normal R-R Intervals (SDNN), and decreased Mean Heart Rate and Physical Stress Index (PSI) levels, with statistical significance (P<0.05). In Frequency Domain Analysis, series of moxa treatments have increased Total Power (TP), Very Low Frequency Oscillation Power (VLF), High Frequency Oscillation Power (HF), normalized HF values while decreasing Low Frequency Oscillation Power (LF), normalized LF and LF/HF ratio with statistical significance (P<0.05). The values of ANS activity, ANS balance, Stress resistance, Stress index, have also shown significant changes. For cardiac stability stroke volume power (SP) and Blood Vessel Tension (BVT) were followed, which were both increased after treatment. All changes were statistically significant (P<0.05). Conclusion : The results have shown a positive correlation between the moxibustion treatments and autonomic nervous system responses on cancer patients through the HRV biofeedback testing. This study suggests possible application of moxibustion treatments for managing ANS functions of cancer patients, although additional studies with larger population are necessary to confirm the data.

경추 척수병증 환자에 있어서 Phase-Contrast Cine MRI 평가의 임상적 유용성 (Clinical Usefulness of Phase-Contrast Cine MRI Evaluation in Patients with Cervical Myelopathy)

  • 임정환;송준혁;신규만;김성학
    • Journal of Korean Neurosurgical Society
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    • 제29권12호
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    • pp.1634-1641
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    • 2000
  • Objective : The cerebrospinal fluid(CSF) pulsates within the craniospinal axis in response to rhythmic cerebral blood volume variation during the cardiac cycle. The aim of this study is to characterize the normal and abnormal CSF flow and its waveforms in the cervical spinal subarachnoid space. Methods : The magnetic resonance(MR) images were obtained with 1.5 T(GE Signa, GE Medical Systems, Milwaukee, USA) unit using the 2 dimensional cine PC(phase contrast) sequence with cardiac gating and gradient recalled echo imaging. This pulse sequence yielded 16 quantitative flow-encoded images per cardiac cycle. Sagittal and axial images of the cervical spinal CSF space were obtained, and target sites were analyzed for characteristic CSF flow (TR=50ms, TE=12.5-15ms). The region of interest(ROI) was 1mm 3 in volume. Twenty six persons were included in this study : 10 healthy volunteers and 16 patients with cervical myelopathy. The post-operative cine MR study were also done in five patients. Results : The normal CSF pulsation dynamics in the cervical spine showed discrete systolic and diastolic components. The CSF flow revealed a sine wave pattern, in which the systolic phase was shorter than the diastolic phase(ratio=2 : 3). The patient group revealed decreased amplitudes of the CSF flow and irregularly distored flow waves. The systolic phase was elongated in the ROI above the stenotic level, whereas the diastolic phase was lengthened below the level. In the postoperative images, the abnormal pattern and amplitude were found to be corrected. Conclusion : From these results, the authors believe that the CSF flow study provides valuable informations regarding the extent of cervical stenosis and may be useful for the surgical planning and post-operative evaluation.

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흡연 여대생의 혈청 지질, Cu, Zn, Ceruloplasmin 농도 및 Ferroxidase 활성도 (Levels of Serum Lipids, Copper, Zinc, Ceruloplasmin and Ferroxidase Activity in Smoking College Women)

  • 김정희;이화신
    • 대한지역사회영양학회지
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    • 제2권4호
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    • pp.515-522
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    • 1997
  • This study was done to compare serum levels of lipids, trace minerals, ceruloplasmin and ferroxidase activity between female college smokers and nonsmokers. Serum levels of lipids, Cu, Zn, ceruloplasmin and ferroxidase activity were determined in 33 smokers and 42 nonsmokers residing in the Seoul area. Serum levels of TG, total cholesterol and HDl-cholesterol were measured using test kits. Serum Cu Zn were determined by the AAS. Serum ceruloplasimin level and ferroxidase activity were determined by spectrophotometric methods. All data were statistically analyzed by the SAS PC package program. Mean and standard errors were calculated for each item, and the significance of the difference between two groups was evaluated by Student's t-test at p〈0.05. There was no significant difference in levels of total cholesterol, TG, VLDL-cholesterol, LDL-cholesterol, LDL/HDL and atherogenic index, but HDL-cholesterol level was significantly lower(p$\ll$0.05) in female college smokers than in nonsmokers. Serum zinc level showed no significant difference, whereas copper level was significantly higher in smokers, consequently yielding higher Cu/Zn ratio in smoking college women. Ceruloplasmin level was 32.6mg/dl in smoking college women, which was significantly higher(p$\ll$0.05) than that of 28.6mg/dl in nonsmokers. However, cerulopasmin ferroxidase activity, 0.34U/mg in nonsmokers was higher(p$\ll$0.05) than that of 0.29U/mg in smokers. From these results, it is confirmed that cigarette smoking itself has a very detrimental effect on health and mineral nutritional status although the smoking history is relatively short among college women(pack-years=1.7). (Korean J Community Nutrition 2(4) : 515-522, 1997)

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첨가물질을 달리한 혼합전분겔의 텍스쳐 특성 (Textural Characteristics of Mixed Starch Gels with Various Additives)

  • 이상금;신말식
    • 한국식품과학회지
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    • 제27권6호
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    • pp.928-933
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    • 1995
  • 탈지옥수수전분겔의 텍스쳐 특성을 향상시켜 묵으로서의 사용 가능성을 높이기 위하여 탈지옥수수전분에 녹두전분을 일정비율로 혼합하고 여러가지 첨가물질을 넣어 전분겔을 제조하고 24시간과 72시간 저장한 다음 관능적, 기계적인 방법으로 텍스쳐 특성을 알아보았다. 탈지옥수수전분과 녹두전분의 혼합비율은 60 : 40(%, w/w)일때 가장 좋았다. 혼합전분에 조직 콩단백, 콩기름, 셀룰로오스 유도체, 펙틴을 1%와 2% 첨가하여 제조한 혼합전분겔의 관능적인 검사에서 24시간 저장한 전분겔은 첨가물질에 관계없이 부서짐성의 감소와 응집성 그리고 탄성이 증가하였으나 종합적인 맛은 대조군 보다 낮았다. 72시간 저장한 전분겔에 TSP를 첨가하면 견고성, 응집성, 촉촉함의 증가와 부서짐성이 감소하였고, SO는 견고성과 응집성을 높였으며, CMC는 견고성, 부서짐성, 응집성은 높였으나 휘어짐성과 탄성은 감소시켰다. 펙틴은 함량에 따라 차이를 보여 1%에서는 휘어짐성, 촉촉함과 부드러움성이 증가하고 2%에서는 견고성과 응집성이 증가하였다. 기계적 검사에서는 관능검사와는 달리 견고성은 변화가 없고 응집성과 탄성은 증가하였으며 정도는 첨가물질의 종류나 함량에 따라 차이를 보였다.

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측두하악장애 환자에서 과두크기와 관절융기의 후방경사에 관한 연구 (A STUDY ON THE SIZE OF CONDYLE AND THE POSTERIOR SLOPE OF THE ARTICULAR EMINENCE IN PATIENTS WITH TEMPOROMANDIBULAR JOINT DISORDERS.)

  • 박원희;심광섭;우순섭;이영수
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제22권1호
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    • pp.43-50
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    • 2000
  • The purpose of this study was to investigate the interrelationship between temporomandibular joint disorders, and the condyle size and angle of the posterior slope of the articular eminence. The subjects used in this study were 100 patients with temporomandibular joint disorders and 100 volunteers with normal temporomandibular joints. All the patients and the volunteers were subjected to take panoramic and temporomandibular radiographs for the morphologic evaluation. The films were traced, measured, and analyzed. The data were processed with SPSS/PC+ package for statistical analysis. The obtained results were as follows; 1. The posterior slope of the articular eminence in the group of temporomandibular joint disorders was larger than that in the normal group (p<0.05). The mean articular eminence angle was $31.6^{\circ}\;{\pm}\;6.3$ in the group of temporomandibular joint disorder, and $29.9^{\circ}\;{\pm}\;8.4$ in the normal group. 2. There were no statistically significant differences in the discrepancies of the left and right articular eminence angular measurements between the group (p>0.05). 3. There were no statistically significant differences in the condylar ratio between the groups (p>0.05). 4. There were no statistically significant differences in the discrepancies of the left and right ramus length measurements between the groups (p>0.05). 5. The relative size of condyle to fossa in the group of temporomandibular disorders was smaller than that in the normal group (p<0.05).

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사상체질분류검사(四象體質分類檢査)(QSCC)의 타당화연구(妥當化硏究) (A Validation Study of the Questionnaire of Sasang Constitution Classification(QSCC))

  • 김선호;고병희;송일병
    • 사상체질의학회지
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    • 제5권1호
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    • pp.67-85
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    • 1993
  • The Purpose of this study was to evaluate the reliability and the validation of four scales of Questionnaire for Sasang Constitution Classification (QSCC), newly constructed through statistical item analysis and to examine their diagnostic discrimination power. QSCC was administered to 105 inpatient at Kyung-Hee Oriental Medicine Hospital and local oriental clinics and 136 undergraduated students. 2 weeks later, QSCC was readministered to 220 same subjects. Data were collected during about 2 months from february to Apr. 20, 1992. For the purposes of this study, the collected data were analyzed by internal consistancy, test-retest reliability, ANOVA, Pearson correlation and discrimination analysis of spss pc+ v3.0 program. The results were as follows: 1. The reliability of four scales of QSCC was relatively favorable. The internal consistancy and test-retest reliability of Tae-Yaung-In(太陽人) scale were respectively Cronbach's ${\alpha}=0.9$ and r=0.89. Those of So-Yaung-In(少陽人) scale were respectively ${\alpha}=0.81$ and r=0.93. Those of Tae-Em-In(太陰人) scale were respectively ${\alpha}=0.72$ and r=0.74. Those of So-Em-In(少陰人) scale were respectively ${\alpha}=0.81$ and r=0.93. 2. The diagnostic discrimination abilities(Hit-ratio=56%)of QSCC were found to have more about 20% improvement than propotional chance criteria(37%). Especially, Hit-ratios for So-Yaung-In(63%) and Tae-Em-In(60%) were more high than that for So-Em-In(48%) 3. For male subjects, the construct validity of QSCC was founded to be relatively favorable. But that of QSCC for females was poor.

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다중 스레드를 이용한 실시간 동판 검사 시스템 (A Real-time Copper Foil Inspection System using Multi-thread)

  • 이재광;최동혁
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제10권6호
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    • pp.499-506
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    • 2004
  • 제안된 동판 표면 검사 시스템은 PC-기반으로 다중 스레드 기법과 다중 CPU를 이용해 동판 표면의 결함을 실시간으로 검사하는 시스템이다. 초고속 라인 스캔 카메라로 영상 취득 보드에 영상을 실시간으로 취득하여 처리할 때, 더블 버퍼링 방법으로 입출력과 처리가 동시에 수행되어 처리 속도를 높인다. 다중 스레드 기법에서는 시스템 자원 활용과 다중 스레드로 CPU의 사용을 최대화하여 실시간 처리하며, 다중 스레드 구조로도 실시간 처리가 어려운 경우에는 다중 CPU를 사용하여 이를 해결한다. 또한 동판 표면 영상에서 결함 검출하여 분류할 때, 실시간 처리를 만족시키기 위해서 결함영상의 공분산 행렬의 고유치 비율, 명암차 등의 연산으로 분류할 수 있는 방법을 제시한다. 결함의 검출은 조명 불균형에 대한 보상 처리가 적용된 다음 임계치에 의해 검출된다. 검출된 결함은 제안된 분류 방법으로 특징을 분석한 뒤 결함의 형태를 분류한다. 특징은 결함 너비와 고유치 비율, 명암차 등이 사용되었다. 제시된 방법을 검증하기 위해서 총 141개의 결함을 분류하는 실험이 진행되었고, 결과로는 89.4% 성공률을 보였다.