• 한국항행학회논문지
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• 제17권3호
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• pp.279-284
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• 2013

운항의 여러 단계 중 착륙단계에서 조종사들이 많은 부담을 느낀다. 이는 조종사들이 항공기 속도를 줄이고 접지하여 완전히 정지하는 동안 착륙안전에 영향을 미치는 여러 요소가 있기 때문이다. 만일 착륙하는데 활주로길이가 충분하다면 부담이 적을 수도 있다. 그러나 항상 그런 경우만 있는 것은 아니다. 따라서 착륙성능이 제한범위 내에 있는지 아닌지를 확인할 필요가 있다. 필요착륙거리는 시험비행 조종사에 의해 실증되어진 실제착륙거리에다가 항공사의 평균적인 조종사들을 위한 여유분을 포함한 것이다. FAR의 AFM(항공기 비행규정) 인가는 건조 및 습윤 활주로에서 수동착륙을 기반으로 한다. 기타 다른 활주로 조건에서는 인가가 필요하지 않다. JAR에서는 빙설/윤활활주로에서도 정해진 여유분을 포함시키도록 규정하고 있다. 자동착륙은 인가사항이 아니므로 실제착륙거리만 제공된다. 본 논문에서는 각 활주로 조건에서 포함된 거리 여유분을 분석하고자 한다. 또한 특정한 활주로 조건에서 여유분이 규정되어 있지 않은 경우 대안을 제시하고자 한다.

• 여성건강간호학회지
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• 제4권1호
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• pp.47-66
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• 1998

The purpose of this study is to investigate the relationship between menopausal symptoms and spiritual well-being. In order to collect the research data, 350 questionaries were sent to the middle aged women who were 40-59 years old. During the collection period, March 20, 1977-April 20, 1977, 264 questionaries were collected. The questionnaire was prepared by using other researchers' scale, such as menopausal symptom scale by Neugarton and spiritual well-being scale by Paloutzian & Ellison. The research data were analyzed by various testable methods, such as frequency, t-test or ANOVA, and Pearson's correlation. The main results of this study were as follows ; Among the general characteristic variables, some variables have statistical significancy in explaining the difference of the menopausal symptoms. Such variables include age(F=5.17, p=0.002), years get married(F=4.23, p=0.002), number of children(F=3.08, p=0.028), income level of family(F=3.07, p=0.017), life style at leisure time(F=2.47, p=0.045). Some variables related to health condition could explain the differences of the menopausal symptoms among middle aged women. current menstruation stage(F=9.82, p=0.000), current health condition(F=9.82, p=0.000), and experience being operated in the past(F=9.82, p=0.000) are related to the menopausal symptoms. Serious menopausal symptoms which could be found in this study were 'back pain and joint pains(2.6)', nervousness(2.4), and psychosomatic symptom(1.97). Spiritual well-being inquiries could be classified into two subgroups, existential and religious. The mean score of existential well-being(3.04) was higher than that of religious well-being(2.76). Relatively higher existential well-being(3.10) was found in the women who have stable menstruation cycle. The age when the menopause began was related to spiritual well-being(F=3.29, p=0.046). The correlation between menopausal symptoms and spiritual well-being was statistically significant(r=-0.133, p=0.031). Based on the above results, nursing intervention program of menopausal symptoms is recommended in order to promote the health of middle-aged women.

• Journal of Welding and Joining
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• 제28권3호
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• pp.49-58
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• 2010

Various alloy system, such as Cu-Sn-Ti, Cu-Ag-Ti, and Ni-B-Cr-based alloy are used for the brazing of diamond grits. However, the problem of the adhesion strength between the diamond grits and the brazed alloy is presented. The adhesion strength between the diamond grits and the melting filler alloy is predicted by the contact angle, thereby, instead of diamond grit, the study on the wettability between the graphite and the brazing alloy has been indirectly executed. In this study, Cu-13Sn-12Ti filler alloy was manufactured, and the contact angles, the shear strengths and the interfacial area between the graphites (diamond grits) and braze matrix were investigated. The contact angle was decreased on increasing holding time and temperature. The results of shear strength of the graphite joints brazed filler alloys were observed that the joints applied Cu-13Sn-12Ti alloy at brazing temperature $940^{\circ}C$ was very sound condition indicating the shear tensile value of 23.8 MPa because of existing the widest carbide(TiC) reaction layers. The micrograph of wettability of the diamond grit brazed filler alloys were observed that the brazement applied Cu-13Sn-12Ti alloy at brazing temperature $990^{\circ}C$ was very sound condition because of existing a few TiC grains in the vicinity of the TiC layers.

• 한국인터넷방송통신학회논문지
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• 제19권5호
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• pp.55-62
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• 2019

본 논문에서는 K 사용자 MIMO 간섭 채널을 고려하였으며, 정보와 전력을 동시에 전송하는 SWIPT 시스템을 위한 송수신기 설계 방법에 대해서 다룬다. 그리고, 정보 수신 장치와 전력 수확 장치가 같은 수신기에 존재하는 SWIPT 시스템을 고려한다. 제안하는 방식에서는 신호대 누수 잡음비 (SLNR)를 비용 함수로 사용하고, 수확 전력에 대한 임계값을 만족하도록 송수신기를 설계한다. 즉, 수확 전력에 대한 제약 조건 하에서, SLNR을 최대화시키도록 송신단 프리코딩 벡터, 수신단 검파기 벡터, 전력 분배 상수를 동시에 설계한다. 컴퓨터 모의실험을 통하여, 제안하는 기법과 기존 기법의 신호 대 간섭 잡음비 (SINR) 성능을 비교하였다. 사용자 수, 송신 안테나 개수, 수신 안테나 개수 간의 특별한 제약 조건을 만족하는 경우, 제안하는 기법은 낮은 SNR에서 기존 기법보다 우수한 SINR 성능을 나타낸다는 것을 보였다. 또한, 특별한 제약 조건을 만족하지 못하는 경우에는, 제안 기법이 모든 SNR 범위에 대해서 기존 기법보다 더 우수한 성능을 나타낸다는 것을 보였다.

• Physical Therapy Rehabilitation Science
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• 제8권3호
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• pp.162-169
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• 2019

Objective: The purpose of this study was to investigate the conditions for the application of various plank exercises to people who require trunk stabilization by comparing trunk muscle activity according to the degree of hip abduction in the plank exercise. Design: Cross-sectional study. Methods: Twenty healthy participants voluntarily participated in this study and the plank exercise was performed under 5 conditions (two-legged support plank [TSP] with hip abduction, TSP with hip abduction of 15 degrees, TSP with hip abduction of 30, one-legged support plank [OSP] with hip abduction of 15 degrees, OSP with hip abduction of 30 degrees). In order to measure the trunk muscle activity according to the 5 conditions, surface electromyography was used. The electrical activities of the rectus abdominis (RA), external oblique (EO), and internal oblique (IO) muscles were measured during the 5 plank exercises. Subjects practiced each of the 5 conditions three times in random order and the average values were obtained. Results: In the OSP condition with 15/30 degrees of hip abduction, activities of the RA, EO, and IO were significantly greater than during the TSP (p<0.05). In the OSP with 30 degrees of hip abduction condition, activities of the left EO, IO were significantly greater than other plank exercise conditions (p<0.05). Conclusions: The plank exercise with hip abduction of 30 degrees and the OSP exercise can be suggested as an effective method to enhance the activity of the trunk oblique muscles.

• Advances in concrete construction
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• 제11권5호
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• pp.375-386
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• 2021

In this paper, a study of stability and health of a newly-built railway tunnel is presented. The field test was implemented to monitor the secondary lining due to the significant cracking behaviors influenced the stability and health of the tunnel structure. Surface strain gauges were installed for monitoring the status of crack openings, and the monitoring outputs demonstrated that the cracks were still in the developing stage. Additionally, adjacent tunnel and poor condition of surrounding rock were identified as the causes of the lining cracking by systematically characterizing the crack spatial distribution, tunnel site and surrounding rock conditions. Reconstruction of partial lining and reconstruction of the whole secondary lining were designed as the maintenance projects for different cracking regions based on the construction feasibility. For assessing the health conditions of the reinforced lining, embedded strain gauges were set up to continuously measure the strain and the internal force of the reconstructed structures. For the partially reconstructed lining, the outputs show the maximum tensile elongation is 0.018 mm during 227 days, which means the structure has no obvious deformation after maintenance. The one-year monitoring of full-section was implemented in the other two completely reconstructed cross-sections by embedded strain gauge. The outputs show the reconstructed secondary lining has undertaken the pressure of surrounding rock with the time passing. According to the calculated compressive and tensile safety factors, the completely reconstructed lining has been in reliable and safe condition during the past year after reinforcement. It can conclude that the aforementioned maintenance projects can effectively ensure the stability and health of this tunnel.

• 한국운동역학회지
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• 제31권2호
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• pp.140-147
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• 2021

Objective: The purpose of this study is to identify the mechanism of changes in maximum voluntary torque with the magnitude and duration of pre-activation torque during voluntary isometric knee extension. Method: 11 male subjects (age: 25.91±2.43 yrs., height: 173.12±3.51 cm, weight: 76.45±7.74 kg) participated in this study. The subjects were required to produce maximal voluntary isometric torque with a particular pre-activation torque condition. The properties of pre-activation torque consisted of the combinations of 1) three levels of magnitude, e.g., 32 Nm, 64 Nm, 96 Nm, and 2) two levels of duration, e.g., 1 sec, and 3 sec; thus, a total of six conditions were given to the subjects. The force and EMG data were measured using the force transducers and wireless EMG sensor, respectively. Results: The results showed that the maximum voluntary torque increased the most with relatively large and fast (96 Nm, 1 sec) pre-activation condition. Similarly, with relatively large and fast (96 Nm, 1 sec) preactivation, it was found that the integrated EMG (iEMG) of the agonist muscles increased, while no significant changes in the co-contraction of the antagonist muscles for the knee extension. Also, the effect of pre-activation conditions on the rate of torque development was not statistically significant. Conclusion: The current findings suggest that relatively larger in magnitude and shorter in duration as the properties of pre-activation lead to a larger magnitude of maximal voluntary torque, possibly due to the increased activity of the agonist muscles during knee extension.

• Tuberculosis and Respiratory Diseases
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• 제85권1호
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• pp.1-10
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• 2022

Pulmonary hypertension (PH) is a condition of increased blood pressure in the pulmonary arteries and is diagnosed with an increased a mean pulmonary artery pressure ≥25 mm Hg. This condition may be associated with multiple clinical situations. Based on pathophysiological mechanisms, clinical presentation, hemodynamic profiles, and treatment strategies, the patients were classified into five clinical groups. Although there have been major advances in the management of PH, it is still associated with significant morbidity and mortality. The diagnosis and treatment of PH have been performed mainly by following European guidelines, even in Korea because the country lacks localized PH guidelines. European treatment guidelines do not reflect the actual status of Korea. Therefore, the European diagnosis and treatment of PH have not been tailored well to suit the needs of Korean patients with PH. To address this issue, we developed this guideline to facilitate the diagnosis and treatment of PH appropriately in Korea, a country where the consensus for the diagnosis and treatment of PH remains insufficient. This is the first edition of the guidelines for the diagnosis and treatment of PH in Korea, and it is primarily based on the '2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension.' with the acceptance and adaptation of recent publications of PH.

• 대한본초학회지
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• 제32권6호
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• pp.31-39
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• 2017

Objectives : Menopausal symptoms are characteristic symptoms which are occur in women before and after menopause. In Western medicine, hormone therapies are mainly used but patients show reluctance because they exhibit serious side effects. In Oriental medicine, there are also limits to the treatment. So I tried to find a new easily accessible treatment. I performed the experiments to verify the effect of natural dyed apparel with Indigo and Schisandra fruit. Methods : This experiment was performed on 30 women who were experiencing menopausal symptoms. We checked the participant's general condition through questionnaire and physical condition with inbody test and made natural-dyed living suit style dresses. We asked the women to wear the apparel for four weeks. They checked for changes in symptoms weekly with kupperman's index. Results : The main symptoms of participants are sweating, hot flushes, joint pain. After wearing of the apparel, there were decreased hot flushes, sleep improvement, psychological stability etc. According to the kupperman's index, patients with mild symptoms were 13.3% at first week to start the experiment but four weeks later, patients with mild symptoms were increased to 50%. On the other hand, patients with severe symptoms were decreased 33.3% to 6.7%. In the test results, there was a significant decrease in 1, 2 and 3 weeks, there was a decrease in 4 weeks but no significance in the figure Conclusion : Natural dyed apprel with Indigo and Schisandra fruit was effective on treating women who were experiencing menopausal symptoms.

• Geomechanics and Engineering
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• 제36권3호
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• pp.303-316
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• 2024

Seismic records are composed of mainshock and a series of aftershocks which often result in the incremental damage to underground structures and bring great challenges to the rescue of post-disaster and the repair of post-earthquake. In this paper, the repetition method was used to construct the mainshock-aftershocks sequence which was used as the input ground motion for the analysis of dynamic time history. Based on the Daikai station, the two-dimensional finite element model of soil-station was established to explore the failure process of station under different seismic precautionary intensities, and the concept of incremental damage of station was introduced to quantitatively analyze the damage condition of structure under the action of mainshock and two aftershocks. An arc rubber bearing was proposed for the shock absorption. With the arc rubber bearing, the mode of the traditional column end connection was changed from "fixed connection" to "hinged joint", and the ductility of the structure was significantly improved. The results show that the damage condition of the subway station is closely related to the magnitude of the mainshock. When the magnitude of the mainshock is low, the incremental damage to the structure caused by the subsequent aftershocks is little. When the magnitude of the mainshock is high, the subsequent aftershocks will cause serious incremental damage to the structure, and may even lead to the collapse of the station. The arc rubber bearing can reduce the damage to the station. The results can offer a reference for the seismic design of subway stations under the action of mainshock-aftershocks.