• 제목/요약/키워드: Low effective index

검색결과 540건 처리시간 0.031초

자외선 스펙트럼을 이용한 별의 표면온도 결정 (DETERMINATION OF STELLAR SURFACE TEMPERAURE USING ULTRAVIOLET SPECTRA)

  • 강영운;지나현;한미려;최영준;한원용;이우백
    • Journal of Astronomy and Space Sciences
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    • 제15권1호
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    • pp.91-100
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    • 1998
  • 자외선 영역에서 색지수와 유효온도의 상관관계를 구하기 위한 pilot project 로 25개의 표준상태에 대하여 유효온도와 색지수를 산출하였다. 유효온도는 자외선 영역의 IUE 저분산 스펙트럼의 에너지 분포 곡선을 Kurucx 모델과 비교하여 산출하였고, 자외선 색지수는 IUE 저분산 스펙트럼의 플럭스를 $300{\AA}$ 단위로 적분하여 등급으로 환산하여 산출하였다. 자외선 영역으 상관관계는 가시관선 영역의 상관관계와 유사한 형태로 나타났다.

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한국 5월 가뭄과 북태평양진동의 연관성 (Relationship between Korean Drought and North Pacific Oscillation in May)

  • 최기선;김도우;이지선;변희룡
    • 대기
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    • 제19권1호
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    • pp.67-78
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    • 2009
  • A strong negative correlation has been detected between the North Pacific Oscillation Index (NPI) and the Effective Drought Index (EDI) in May over Korea. In May of positive NPI year, anomalous patterns caused a drought in Korea as follows: the anomalous south-low, north-high low-level pressure patterns in the northeast and southeast of Korea have strengthened the anomalous northerlies to Korea. In addition, these anomalous northerlies have prevented western North Pacific (WNP) high from moving northward. As a result, anomalous descending flows have strengthened in the mid-latitude region in East Asia. In the WNP, the anomalous south-high, north-low sea surface temperature (SST) has been widely distributed, which has strengthened anomalous south-low, north-high low-level pressure patterns. These anomalous characteristics of pressure and SST patterns observed in May of positive NPI years have already been detected in previous winter (December-February) and early spring (March, April). In addition, the anomalous negative sea ice concentration in the North Pacific during two seasons has strengthened the anomalous anticyclonic circulation in the same region and in turn made a contribution to formation of anomalous south-low, north-high pressure patterns in May.

Zn-Vapor확산에 의한 Ti:LiTaO$_{3}$ 광도파로의 굴절률 증가에 관한 연구 (A study on the enhancement of refractive index in Ti:LiTaO$_{3}$ optical waveguides by Zn-vapor diffusion)

  • 정홍식;정영식
    • E2M - 전기 전자와 첨단 소재
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    • 제9권3호
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    • pp.298-303
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    • 1996
  • A double diffusion technique is developed to enhance the effective mode index of optical waveguides in $LiTaO_3$. It consists of Zn diffusion from the vapor phase at relatively low temperatures (750->$800^{\circ}C$), into waveguides initially produced by Ti indiffusion at higher temperature (1150->$1200^{\circ}C$). Both X- and Z-cut substrates are investigated. A model that combines profiles of both diffusion is formulated to calculate the expected effective index values for planar waveguides. Good agreement is found between experimental results and model predictions which assume that the initial Ti profile is not affected by the lower temperature Zn diffusion. Effective index enhancements as high as 0.005 and 0.003 are obtained by this method for the fundamental extraordinary and ordinary modes, respectively.

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능동이완기법이 만성 허리통증 환자의 통증, 요통장애지수 및 골반비대칭에 미치는 영향 (Effects of Active Release Technique on Pain, Oswestry Disability Index and Pelvic Asymmetry in Chronic Low Back Pain Patients)

  • 이승후;남승민
    • 대한물리의학회지
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    • 제15권1호
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    • pp.133-141
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    • 2020
  • PURPOSE: This study examined the effects of active release technique on pain, Oswestry Disability Index, and pelvic asymmetry in chronic low back pain patients. METHODS: Thirty five outpatients diagnosed with chronic low back pain were enrolled in this study. The patients were divided randomly into an active release technique therapy group(experimental group; n=18) and myofascial release technique therapy group(control group; n=17). These groups performed their respective therapy for a 40-minute session occurring twice a week over six weeks. The Visual Analogue Scale(VAS) was used to measure the subjects' pain, and the Korean Oswestry Disability Index(KODI) was used to measure the subjects' dysfunction. To assess the patients' pelvic asymmetry, their pelvic tilt and pelvic rotation were measured using X-ray imaging. RESULTS: Both the experimental group and control group exhibited significant decreases in their VAS and KODI scores after the therapy(p<.05). The experimental group exhibited a significant decrease in their pelvic tilt and pelvic rotation after therapy(p<.05). A significant difference was observed between the experimental group and the control group (p<.05). CONCLUSION: These results suggest that active release technique is effective in decreasing the level of pain and dysfunction in chronic low back pain patients. In addition, the active release technique is considered to be more effective in improving the pelvic tilt and pelvic rotation than myofascial release technique. This can be an effective method for the non-pharmacological and non-surgical treatment of chronic low back pain.

허리관절가동기법이 만성요통환자의 균형과 요통 기능장애 지수에 미치는 영향 (The Effect of Spine Mobilization Technique on Balance and the Low Back Pain Disability Index of Patients with Chronic Back Pain)

  • 양대중;박승규;강정일;김제호;정대근;김영일;엄요한
    • 대한통합의학회지
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    • 제6권4호
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    • pp.139-148
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    • 2018
  • Purpose : The purpose of this study was to examine the effects of waist mobilization technique intervention for patients with chronic back pain on balance and the low back pain disability index. Methods : The subjects were 30 patients with chronic back pain. They were sampled and divided into a manual therapy group and a spinal decompression group. 15 subjects were randomly assigned to each group. Each training in this study participated for 6 weeks, 5 times a week, once a day, 15 minutes a day. Balance ability was measured with a balance analyzer, and the low back pain disability index was measured using the Oswestry Disability Index (ODI). Results : In the balance abilities, there was a significant difference in the manual therapy group compared to the spinal decompression group. In the low back pain disability index, there was a significant difference in the manual therapy group compared to the spinal decompression group. Conclusion : The analysis results of the effect of 6 weeks of waist mobilization technique intervention on the balance and low back pain disability index for patients with chronic back pain revealed that the manual therapy is more effective for static and dynamic balance ability and the low back pain disability index. In the future, we can promote independent life skills and expect a rapid recovery of patients with chronic back pain. Based on this study, further studies are needed on the effects of balance, the mechanical properties of muscle, and the low back pain disability index depending on various manual therapy techniques.

원자력 발전소 안전체감에 관한 연구: 안전체감지수 개발과 안전체감 수준 (Developing the Nuclear Effective Safety Index)

  • 최인철 ;김범준
    • 한국심리학회지 : 문화 및 사회문제
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    • 제13권3호
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    • pp.1-21
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    • 2007
  • 본 연구에서는 1) 원자력 발전소 지역 주민들의 안전체감을 구성하고 있는 하위요인들을 규명하고, 2) 그 구성요소들의 측정을 통해 주민들의 안전체감지수를 산출하며, 3) 주민들이 체감하는 안전의 정도와 발전소 직원들이 추측하는 주민들의 안전 체감 정도를 비교하였다. 이를 위해 원자력 발전소 지역주민 800명을 대상으로 연구 1과 발전소 직원 187명을 대상으로 연구 2가 수행되었다. 연구 결과에 따르면, 안전체감은 커뮤니케이션, 신뢰, 발전소 위험대응역량, 그리고 응급대응역량의 4가지 요소로 구성되어 있는 것으로 밝혀졌다. 개발된 안전체감 지수에 따르면 발전소 지역 주민들의 안전체감 수준은 매우 낮았으며(100점 만점에 38.22점), 이 점수는 발전소 지역에 따라 다른 것으로 나타났다. 또한 원자력 발전소의 직원들은 주민들이 실제로 체감하고 있는 것보다 주민들이 발전소를 훨씬 더 안전하게 지각하고 있을 것이라고 착각하고 있는 것으로 나타났다. 이 결과의 시사점 및 후속 연구에 대해 논의하였다.

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Measurement of Effective Refractive Index of Anodic Aluminum Oxide Using a Prism Coupler

  • Gong, Su-Hyun;Cho, Y.H.;Stolz, Arnaud;Gokarna, Anisha;Dogheche, Elhadj;Ryu, Sang-Wan
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.195-195
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    • 2010
  • In recent years, Anodic aluminum oxide(AAO) has become popular and attractive materials. It can be easily fabricated and self-organized pore structures. It has been widely used as a biosensor membrane, photonic crystal for optical circuit and template for nanotube growth etc. In previous papers, the theory was developed that AAO shows anisotropic optical properties, since it has anisotropic structure with numerous cylindrical pores. It gives rise to the anisotropy of the refractive index called as birefringence. It can be used as conventional polarizing elements with high efficiency and low cost. Therefore, we would like to compare the theory and experimental results in this study. One method which can measure effective refractive index of thin film is the prism coupling technique. It can give accurate results fast and simply. Furthermore, we can also measure separately the refractive index with different polarization using polarization of the laser (TE mode and TM mode). We calculated the effective refractive index with effective medium approximations (EMAs) by pore size in the SEM image. EMAs are physical models that describe the macroscopic system as the homogeneous and typical method of all mean field theories.

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체중조절 식이에서 탄수화물의 비중 : 그 질과 양 (A Minireview on Carbohydrate in Weight Management Diet : The Quantity and the Quality)

  • 이명종;김호준
    • 한방비만학회지
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    • 제5권1호
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    • pp.121-131
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    • 2005
  • During last few decades dietary guidelines for the weight management mainly have focused on a low-fat, high carbohydrate diet. Carbohydrate was supposed to be low-dense, highly satiating as well as it affects little on the lipogenesis. Although low-fat diet has significant weight-reducing effect, the loss was modest and usually regained after cessation of the diet. Furthermore, low-fat, modest-carbohydrate diet did not impact on the ever increasing rates of overweight and obesity. Alternative approaches include low-carbohydrate diet, high-carbohydrate diet and low-glycemic index diet. Although none of above mentioned diet have sufficient evidence for standard weight management diet, short-term efficacy and safety are being approved continuously. Low-carbohydrate diet contains less than 45% of carbohydrate in daily energy consumption, it is claimed to have more satiating effect and to improve metabolism. However, low compliance due to the limitation of food choice should be considered on prescribing the diet. High-carbohydrate which contains 90% of carbohydrate in total daily energy consumption, is effective in providing satiety and lowering total calorie intake and cholesterol. On the other hand, nutritional unbalance should be took into account. Low-glycemic index diet is based on the theory that contemporary diet contains significantly less fiber and unrefined carbohydrate, therefore insulin secretion is disturbed. Because low glycemic index food slowly increase blood glucose and insulin level, it induces much satiating effect and may decrease calorie ultimate intake. However, poor standardization of glycemic index is one of the main obstacle for the diet to be applied in the clinic. Meanwhile, high fructose food and beverage should be discouraged because it has little satiating effect and may cause insulin resistance. High fiber food is another recommendation for healthy, lean diet.

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4-레벨 인버터를 위한 저변조지수 영역의 DC-링크 전압 제어기법 (A DC-Link Voltage Control Scheme for 4-Level Inverter at Low Modulation Index)

  • 송종환
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2000년도 전력전자학술대회 논문집
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    • pp.325-329
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    • 2000
  • An effective Carrier-Based PWM scheme that enables the instantaneous quality of each branch point voltage of a diode clamped 4-level inverter to be reduced at a low modulation index is described. This scheme presents a computed zero sequence voltage of PWM by the feedback of both DC-link voltages and load currents. The proposed PWM scheme enables to increase the controllable region of DC-link voltage and makes it possible to operate with small DC-link capacitors. The validity of the proposed PWM scheme is verified by simulation results.

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Physicochemical Changes in UV-Exposed Low-Density Polyethylene Films

  • Salem, M.A.;Farouk, H.;Kashif, I.
    • Macromolecular Research
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    • 제10권3호
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    • pp.168-173
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    • 2002
  • Unstabilized low-density polyethylene (LDPE) films and films formulated with hindered amine light stabilizer (HALS) were exposed to UV-radiation; and the physicochemical changes during photooxidation processes have been investigated using tensile, FTIR spectre-photometric and thermal analytical (DSC) techniques. The dependence of tensile properties (elongation- and stress-at-break), carboxyl index and heat of fusion on UV-irradiation time have been discussed. The use of HALS is found to be effective in maintaining the UV-mechanical properties of the LDPE films. The experimental results showed that there exists no correlation between mechanical properties and carbonyl index, whereas crystallinity correlates well with carbonyl index in unstabilized and stabilized films for irradiation times greater than 100 h. The rate of formation of carbonyl groups is found to be dependent on UV exposure time. Crystallinity of the film samples is strongly influenced by both exposure time and presence of HALS.