• 대한조선학회논문집
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• 제52권1호
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• pp.61-69
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• 2015

In the beginning of the 1990's, numerous shaft bearing damages, especially in aft stern tube bearing, were reported. The main reasons of bearing damages were estimated that hull deflections have been increased by more flexible hulls and propeller dynamic loads have not been considered in shaft alignment. After that time, studies to take into account hull deflections in shaft alignment have been actively carried out, but for the latter leave much to be desired. In this study, the effects of the propeller forces on the propeller shaft bearing have been investigated by estimating thrust eccentricity as reasonable as possible although some assumptions to simulate turning of ship were introduced. Three dimensional nominal wake to estimate thrust eccentricity have been calculated by using CFD analysis and model test in the towing tank. This study presents the procedure to estimate the propeller eccentric forces and their influence on the stern tube bearing for a container carrier. As a result, it has been found that the lateral propeller forces in turning condition should be considered in shaft alignment to prevent shaft bearing damages.

• Journal of Advanced Marine Engineering and Technology
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• 제23권4호
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• pp.462-472
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• 1999

De-NOx facility using Selective Catalytic Reduction method is the most widely applied one that removes NOx from flue gas emitted from combustion facility such as boiler for power generation engine incinerator etc. Reductant $NH_3\;or\;NH_4OH$ is sprayed into flue gas to convert NOx into $H_2O$ and $N_2.$ Good mixing between flue gas and $NH_3$ is the most important factor to increase reduction in catalytic layer and to reduce unreacted NH3 slip. Therefore the development of mixer device for mixing effect is one of the important part for SCR facility. Objectives of this study are to investigate the relation between flow and concentration field by observation at the wake of delta-wing type mixer. At the first stage qualitative measurement of flow field is conducted by flow visualization using laser light sheet in lab. scale wind tunnel. Also we have conducted the quantitative analysis by comparing flow field measurement using LDV with numerical simulation. On the basis of qualitative and quantitative analysis we investigate the dis-tribution of flow and concentration in flow model facility. The results of an experimental and compu-tational examination of the vortex structures shed from delta wing type vortex generator having $40^{\circ}$ angle of attack are presented, The effects of vortex structure on the gas mixing is discussed, too.

• Journal of Hydrospace Technology
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• 제2권2호
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• pp.44-56
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• 1996

The effects of the air on the reductions in resistance when supplied under the bottom of a semi-planing ship with a step are investigated in the present study. A 1.275m long FRP model is constructed and the pressure and viscous tangential stresses over the planing surface of the hull with and without air supply are measured through measuring holes carefully selected at the towing tank of Seoul National University. Locations of holes most suitable for air injection are surveyed in front of the planing surface of the model with careful examinations of the limiting streamlines and pressure distributions measured without air supply. At those locations, found to be just front of the step, air has been supplied into a wake region to form an air filled cavity of fixed type. Flow rates and pressure of the supplied air as well as the local pressure and shear stress distributions on the hull surface are measured to understand the physics involved as well as to determine the conditions most effective in resistance reduction at the design speed. It has been found that total resistance of the stepped semi-planing hull can be considerably reduced if an air cavity generated by an adequate air injection at the bottom of the hull near the step. After the cavity optimized at the given speed, air bubbles also have been generated right behind the point where dividing streamlines re-attach to further reduce the frictional resistance but found to be not so effective as the air cavity in resistance reductions.

• Wind and Structures
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• 제1권1호
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• pp.1-23
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• 1998

This paper describes wind investigations for the Leaning Tower of Pisa which were conducted as part of an overall evaluation of its behaviour. Normally a short, stiff and heavy building would not be a candidate for detailed wind analyses. However, because of extremely high soil pressures developed from its inclination, there has been increasing concern that environmental loading such as wind actions could combine with existing conditions to cause the collapse of the tower. The studies involved wind assessment at the site as a function of wind direction, analysis of historical wind data to determine extreme wind probabilities of occurrence, estimation of structural properties, analytical and boundary layer wind tunnel investigations of wind loads and evaluation of the response with special concern for loads in the direction of inclination of the tower and significant wake effects from the neighboring cathedral for critical wind directions. The conclusions discuss the role of wind on structural safety, the precision of results attained and possible future studies involving field measurements aimed at validating or improving the analytical and boundary layer wind tunnel based assessments.

• 지역사회간호학회지
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• 제31권4호
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• pp.447-458
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• 2020

Purpose: The purpose of this study was to identify the effects of auricular acupressure therapy on sleep disorder and fatigue in menopausal women. Methods: The study design was a non-equivalent control group pretest-posttest design. The participants were 40~60 years old women, assigned to the experimental group (n=25) or the control group (n=27). Auricular acupressure using vaccaria seeds was administered to the experimental group. The sessions continued for 6 weeks. Outcome measures included Pittsburgh sleep quality index, sleep meter, sleep diary, fatigue assessment instrument, serum cortisol, and serum serotonin. Results: Menopausal women in the experimental group showed significant increases in deep sleep, light sleep, serotonin level and sleep duration compared with the control group. Also, the experimental group reported decreases in PSQI, sleep latency, awakening time, fatigue and cortisol level compared with the control group. Conclusion: Results show that auricular acupressure using vaccaria seeds is considered as an effective treatment for sleep disorder and fatigue in menopausal women. We conclude that it can be used as a nursing intervention method proven to reduce sleep disorder and fatigue in menopausal women.

• 한국유기농업학회지
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• 제30권2호
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• pp.191-206
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• 2022

Rice has prevailed as a staple food in South Korea. Rice consumption has sharply shrunk nowadays. In the wake of COVID-19 Shock and the "untact" era, the instant rice market has significantly grown, and there is a possibility of solving the shrinking consumption of domestic rice. This study contributes to the development of rice consumption promotion strategies by examining the factors of purchasing instant rice based on the Hedonic Price Methodology. In particular, given the increase in online market, this study compares attribute values of product characteristics between online and offline markets. The empirical results show that calorie, brand, organic and functional products have positive effects on instant rice prices. The rate of carbohydrate, the PB and bundle attributes have negative effects on instant rice prices. The results also show that the magnitude of brand, bundle and PB attribute values are bigger in offline market while that of the number of multigrain attribute value is relatively bigger in online market. The organic attribute value is important regardless of marketing channels.

• Asian Journal for Public Opinion Research
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• 제12권2호
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• pp.75-101
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• 2024

This study investigates the variation in anxiety levels across income classes in the wake of the COVID-19 pandemic in Indonesia. The research is based on data from nationally representative surveys conducted in 2017 and 2021, and it employs a multilevel mixed-effects ordered logistic model. The unique aspect of this investigation lies in its utilization of the Cantril ladder, a commonly employed tool in public opinion research, to gauge anxiety levels. Participants are prompted to assess their present life circumstances concerning their daily worries and anxieties. The empirical findings provide evidence that individuals in provinces with higher exposures to COVID-19 reported heightened anxiety levels. Furthermore, the results highlight a consistent association between higher household income and lower levels of anxiety. Notably, individuals from the highest income group experienced a substantial decline in anxiety levels during the pandemic. When examining specific income classes, the study reveals heightened anxiety among women in higher-income brackets and among lower-income households residing in urban areas. Furthermore, regarding macroeconomic circumstances, the results illustrate a positive correlation between economic prosperity and anxiety levels among members of low-income households. The study also uncovers a positive connection between income inequality and self-assessed anxiety within upper-middle and high-income brackets.

• 대한한방내과학회지
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• 제15권2호
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• pp.148-162
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• 1994

A Literature study was done for identifying the effects of Bloodletting on C.V.A. The major results of the study were as follows. 1. The frequency of points of Bloodletting on C.V.A. were in order Twelve well point, Ship son, Gold SalivaJade Fluid, Paekoe, Chungchung, Sugu, Sosang, Taechu, Wijung, Kwanchung, etc. 2. The frequency of meridians of Bloodletting on C.V.A. were in order Extra-point, Tongmaek-kyong, Su-gworum-Shimpo-Kyong, Susoyang-Samcho-Kyong, Sutaeum-Pye-Kyong, Choktaeyang-Panggwang-Kyong. ete. 3. The frequency of the site of points of Bloodletting on C.V.A. were in order four extremities, face, neck and head, etc. 4. The effects of Bloodletting on C.V.A. is clear away heat and alleviate pain, therapy for waking up a patient from unconsciousness, dredge the meridian passage, expel wind-evil and promote blood circulation, emergency treatment for collapse, etc, 5. The effects of Bloodletting on the early stage of C.V.A. were wake up the patient from unconsciousness by clearing away the heat and The effects of Bloodletting on sequence of C.V.A. were dredge the meridian passage, 6. The frequency of points and meridians of Bloodletting on Hemiplegia were in order Twelve well point, Kyonjong, Extra-point, Chok soyang-Tam-Kyong, etc. 7. The frequency of points and meridians of Bloodletting on Aphasia were in order Gold Saliva Jade Fluid, Amun, Extra-point, Tongmaek-Kyong, etc. 8. The frequency of points and meridians of Bloodletting on Quadriplegia were in order Ship son, Twelve well point, Koktaek, Wijung, Extra-point, Chok soyang-Tam-Kyong, etc. 9, The frequency of points and meridians of Bloodletting on Vertigo were in order Four Gods Cleverness, Tuyu. Chanjuk, Paekoe, Taeyang, Extra-point, Yang-Kyong, etc. 10. The frequency of points and meridians of Bloodletting on Headache were in order Taeyang, Paekoe, Taechu, Extra-point, Tongmaek-Kyong, Yang-Kyong, etc. 11. The points and meridians of Bloodletting on Bells palsy were Chichang, Hyopko in Yangmyong-Kyong.

• 수면정신생리
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• 제17권2호
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• pp.85-90
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• 2010

목 적: 인삼은 한국을 비롯한 아시아 국가에서 전통적으로 불면증의 치료에 사용되어 왔으며 쥐를 이용한 동물실험에서 수면을 촉진시키는 효과가 있다는 연구 결과가 있어왔다. 하지만 이러한 효과를 입증할 만한 임상 실험은 거의 이루어지지 않았다. 이에 본 연구에서는 고려 홍삼이 수면에 미치는 영향을 알아보고자 한다. 방 법: 건강한 성인 남성 20명을 대상으로 하였으며 이들은 무작위로 홍삼군과 위약군에 배정되어 2주간의 실험이 진행되었다. 홍삼군의 경우 하루 4,500 mg의 홍삼을 섭취하였다. 실험 시작시점과 2주 후인 종료시점에 수면다원검사를 시행하여 두군간의 변수의 변화를 비교하였다. 결 과: 총 15명의 대상자, 즉 홍삼군 8명과 위약군 7명이 수면다원검사를 시행 받았으며 홍삼군이 위약군 보다 실험 종료 시점에서 3단계 수면이 증가한(p=0.087) 반면에 2단계 수면이 감소하는(p=0.071) 경향을 나타냈다. 결 론: 본 연구 결과는 고려 홍삼이 깊은 잠은 증가시키고 얕은 잠은 감소시키는 경향이 있음을 보여준다. 이는 통계적으로 유의한 결과는 아니지만 홍삼이 수면의 질을 향상시키는 데 효과적임을 짐작하게 한다. 그러나, 보다 많은 대상군과 충분한 홍삼 용량으로 보다 긴 기간 동안 진행되는 연구를 통해 고려 홍삼의 수면에 대한 효과를 확인할 필요가 있다.

• Wind and Structures
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• 제8권2호
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• pp.107-120
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• 2005

The quasi-steady approaches to simulate the wind induced vibrations of inclined cables, especially on the rain-wind induced vibration, have been tried by many researchers. However, the steady wind force coefficients used in those methods include only the effects of water rivulet, but not the axial flow effects. The problem is the direct application of the conventional techniques to the inclined cable aerodynamics. Therefore, in this study, the method to implement the axial flow effects in the quasi-steady theory is considered and its applicability to the inclined cable aerodynamics is investigated. Then, it becomes clear that the perforated splitter plate in the wake of non-yawed circular cylinder can include the effects of axial flow in the steady wind force coefficients for inclined cables to a certain extent. Using the lateral force coefficients measured in this study, the quasi-steady theory may explain the wind induced instabilities of the inclined cables only in the relatively high reduced wind velocity region. When the Scruton number is less than around 40, the high speed vortex-induced vibration occurs around the onset wind velocity region of the galloping, and then, the quasi-steady approach cannot be applied for estimating the response of wind-induced vibration of inclined cable.