• Nuclear Engineering and Technology
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• 제53권3호
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• pp.911-919
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• 2021

In this paper, the design stress intensity values for the plate-type fuel assembly for research reactor are presented. Through a tensile test, the material properties of the cladding (aluminum alloy 6061) and structural material (aluminum alloy 6061-T6), in this case the yield and ultimate tensile strengths, Young's modulus and the elongation, are measured with the temperatures. The empirical equations of the material properties with respect to the temperature are presented. The cladding undergoes several heat treatments and hardening processes during the fabrication process. Cladding strengths are reduced compared to those of the raw material during annealing. Up to a temperature of 150 ℃, the strengths of the cladding do not significantly decrease due to the dislocations generated from the cold work. However, over 150 ℃, the mechanical strengths begin to decrease, mainly due to recrystallization, dislocation recovery and precipitate growth. Taking into account the uncertainty of the 95% probability and 95% confidence level, the design stress intensities of the cladding and structural materials are established. The presented design stress intensity values become the basis of the stress design criteria for a safety analysis of plate-type fuels.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.149-158
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• 2009

American sycamore seedlings were grown in chambers with two different ozone concentrations ($O_3$-free air and air with additional $O_3$) for 45 days. Both the control and the $O_3$ chambers included non-fertilized and fertilized plants. After 18 days of $O_3$ fumigation, seedlings were placed in a clean chamber for 27 days. Seedlings under ozone fumigation showed a significant decrease in pigment contents and photosynthetic activity, and a significant increase in lipid peroxidation. Fertilization enhanced physiological damage such as the inhibition of photosynthetic activity and the increase of lipid peroxidation under ozone fumigation. During the recovery phase, the physiological damage level of seedlings increased with ozone fumigation. In addition, physiological damage was observed in the fertilized seedlings. Superoxide dismutase (SOD) and glutathione reductase (GR) activities of $O_3$-treated seedlings increased up to 33.8% and 16.3% in the fertilized plants. The increase of SOD activity was higher in the fertilized plants than in the non-fertilized plants. Negative effects of ozone treatment were observed in the biomass of the leaves and the total dry weight of the fertilized sycamore seedlings. The $O_3$-treated seedlings decreased in stem, root and total dry weight, and the loss of biomass was statistically significant in the fertilized plants. In conclusion, physiological disturbance under normal nutrient conditions has an effect on growth response. In contrast, in conditions of energy shortage, although stress represents a physiological inhibition, it does not seem to affect the growth response.

• 대한한의학회지
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• 제27권4호
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• pp.215-224
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• 2006

Objectives : In order to apply useful data to clinical practice, we undertook this study and tried to find factors related with sequelae of facial palsy in relation with patients' age and gender distribution, past history with the disease, condition before onset, duration of recovery time, existence of remaining sequelae, types of the sequelae, and duration for sequelae to disappear. Methods : We evaluated patients' condition (fatigue, stress, chills, cold and so on), past history (diabetes mellitus, hypertension, stroke, herpes zoster, cancer and so on), duration of recovery time, types of the sequelae, age and sequelae distribution as to when the treatments were started as we examined 473 patients who were diagnosed with facial palsy, and visited the Out-patient Department of Acupuncture and Moxibustion of Bundang Oriental Medicine Hospital of Dongguk University through 2003 and 2004. Results : The sequelae of facial palsy were not significantly relevant to the signs found before facial palsy occurred(fatigue, stress, chills, and cold), or to patients' past history (hypertension, diabetes mellitus, facial palsy, herpes zoster). The duration of recovery time was within 30 days for 45.3% of the patients examined in this study, and within 90 days for 72.6%. Evaluating the existence of sequelae in relation to age, we found more in the group comprised of patients aged 50 and over than under 50. We found more sequelae in the group which is consisted of patients who had not been treated until 6 days after than within 5 days from the onset. Conclusion: Attention to sequelae will be needed for patients aged 50 and over and who were not treated until 6 days after the onset, as they had more sequelae.

• 한국융합학회논문지
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• 제9권9호
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• pp.353-362
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• 2018

본 연구는 국내 병원 암 센터 이용 환자의 회복을 위한 움직임 프로그램 구성에서 중요하게 다루어야 할 주제들이 무엇인지를 전문가적 합의를 제안하기 위한 것이다. 최종 확정된 움직임 프로그램 구성 요소의 중요도를 산출한 결과, 첫째, 움직임 촉진을 위한 환경에 대한 의견으로는 쾌적한 시설, 자연채광, 휴게실 공간, 자연친화적 공간의 시설적 측면과 질병에 대한 교육, 참여프로그램, 건강 피드백, 정보 유인물 등이 제시되었다. 둘째, 움직임 프로그램 구성 목적에 대한 의견으로는 암 예방 및 조기검진 홍보와 교육, 암 경험자의 효과적 치료방법 공유, 정확한 정보 전달의 인지적 측면과 심리적 지원 및 스트레스 해소, 삶의 질 향상 등이 제시되었다. 셋째, 움직임 프로그램 고려사항에 대한 의견으로는 스트레스 해소, 암 환자의 요구도, 교육의 올바른 정보 전달, 삶의 질, 암 환자의 참여도 등이 제시되었다. 넷째, 움직임 프로그램 애로사항으로는 상이한 신체적 특성, 신체적 불편함, 소극적 참여의 환자 측면과 공간 협소 및 부족, 프로그램 전용 공간 부재 등의 공간측면 등이 제시되었다.

• 운동영양학회지
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• 제25권1호
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• pp.42-55
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• 2021

[Purpose] This study investigated the effects of marine phytoplankton supplementation (Oceanix®, Tetraselmis chuii) on 1) maximal isometric strength and immune function in healthy humans following a oneweek high-intensity resistance-training program and 2) the proinflammatory cytokine response to exercise in a rat model. [Methods] In the human trial, 22 healthy male and female participants were randomly divided into marine phytoplankton and placebo groups. Following baseline testing, participants underwent a 14-day supplement loading phase before completing five consecutive days of intense resistance training. In the rat model, rats were randomly divided into four groups (n=7 per condition): (i) control, (ii) exercise, (iii) exercise + marine phytoplankton (2.55 mg/kg/day), or (iv) exercise + marine phytoplankton (5.1 mg/kg/day). Rats in the exercising groups performed treadmill exercise 5 days per week for 6 weeks. [Results] In the human model, marine phytoplankton prevented significant declines in the isometric peak rate of force development compared to placebo. Additionally, salivary immunoglobulin A concentration was significantly lower following the resistance training protocol in the placebo group but not in the marine phytoplankton group. Marine phytoplankton in exercising rats decreased intramuscular levels and serum concentrations of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) and intramuscular concentrations of malondialdehyde. [Conclusion] Marine phytoplankton prevented decrements in indices of functional exercise recovery and immune function. Mechanistically, these outcomes could be prompted by modulating the oxidative stress and proinflammatory cytokine response to exercise.

• 수면정신생리
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• 제8권1호
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• pp.59-66
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• 2001

목 적 : 본 연구는 정상인에서 바이오피드백 시스템으로 측정된 정신생리적 변인들과 기분 및 성격 특성에 미치는 영향을 알아보고자 하였다. 방 법 : 광고를 통해 모집한 내과적, 정신과적 질환의 병력이 없는 건강한 성인남녀 50명을 대상으로 스필버거 특성불안척도, 베크 우울척도, 성인용 아이젱크 성격검사를 측정하였다. 정신생리학적 변인은 J & J 바이오피드백 시스템을 이용하여 말초피부 온도, 피부전도 반응, 전완 근전도, 전두근 근전도의 수준을 기저기, 스트레스기, 회복기의 3시기로 나누어서 측정하였다. 또한 각 심리척도의 상위 10명, 하위 10명을 고집단(고불안, 고우울, 외향성, 고신경증)과 저집단(저불안, 저우울, 내향성, 저신경증)으로 분류하여 고/저 집단간의 정신생리적 반응의 차이를 t-test, repeated measures ANOVA, Pearson 상관분석을 통해 살펴보았다. 결 과 : 특성불안과 정신생리적 반응과의 관계를 살펴보았을 때, 전완 근전도의 스트레스 반응만이 특성불안과 유의한 상관관계를 나타냈을 뿐(r=0.282, p<0.05), 다른 정신생리적 반응과 연관성은 관찰되지 않았다. 우울감은 기저기와 회복기의 전완 근전도에서 각각 부적 상관관계를 나타냈다(r=-0.299, p<0.05；r=-0.314, p<0.05). 고우울 집단과 저우울 집단을 비교한 결과 전두근 근전도가 스트레스와 회복반응에서 유의한 상호작용 효과를 나타냈다 (F=4.26, p<.05). 외향적인 집단은 내향적인 집단에 비해 스트레스기에 측정된 전완 근전도가 높은 것으로 나타났다. 결 론：본 연구를 통해 정상인에게서 기분과 성격 특성은 바이오피드백 시스템으로 측정한 정신생리적 반응과 연관이 있음을 확인했다. 이는 각종 정신과적 장애에서 동반되는 정신생리적 변인의 이상소견을 해석하는데 있어 반드시 고려해야 할 점으로 생각된다.

• Physical Therapy Rehabilitation Science
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• 제7권4호
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• pp.191-196
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• 2018

Objective: The purpose of this study was to investigate the effects of 5 different personalities on job stress in physical therapists. Design: Descriptive cross-sectional study. Methods: Structured self-report questionnaires consisted of demographic items, 5 types of personalities, and occupational stress. A questionnaire was distributed to 420 physical therapists working in Seoul and Incheon who had voluntarily agreed to participate in the study after the purpose of the study was explained. Of the 420 questionnaires, 405 questionnaires were collected and showed a recovery rate of 96.4%, of which 28 cases were excluded, leaving a total of 377 questionnaires being used for analyses. Pearson correlation analysis was performed to investigate the correlation of job stress and five personalities types. In addition, multiple regression analysis was performed to investigate the effect of general and occupational characteristics of physical therapist on job stress and the effect of personality type on occupational stress. All statistical significance levels were set at p<0.05. Results: The highest number of subjects, which were the physical therapists, showed the tendency to have a sincere personality, followed by affinity, openness, extroversion, and neuroticism. Physical therapists reported to be the most stressed in the order of professional role conflict, overload of work, work relation with a physician and supervisor, interpersonal relationship with patient and caregiver. The higher the level of affinity and sincerity, the lower the amount of stress received by the therapist from the interpersonal relationships between the patient and caregivers. On the other hand, the greater the level of openness and sincerity, the lower the stress levels related to professional role conflict. Conclusions: This study showed that the personality type and job stress of physiotherapists had a statistically significant effect. It is very important for physiotherapists to find their own way of coping with stress, which is satisfactory and appropriate for their job, because it is related not only to individual problems but also to the quality of patient care and medical services. Therefore, it is necessary to continue conducting research on how to relieve the stress levels of physical therapists according to their personality characteristics.

• Structural Engineering and Mechanics
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• 제23권4호
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• pp.339-352
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• 2006

Observing the unique stress-strain curves of the superelastic shape memory alloy (SMA) in tension and compression, the primary intention of this study is to investigate the behavior of the shafts made of the same material, under torsional loading-unloading cycles for large angle of twist. Experiments have been performed for the superelastic SMA shafts with different unsupported lengths and angles of twist and the results are compared with those of stainless steel (SUS304) shafts under similar test conditions. As expected for the superelastic SMA, the residual strains are small enough after each cycle and consequently, the hysteresis under loading-reverse loading is much narrower than that for the SUS304. For large angle of twists, the torsional strength of the superelastic SMA increases nonlinearly and exceeds that of SUS304. Most interestingly, the slender solid superelastic SMA shafts are found to buckle when acted upon torsion for large angle of twist.

• 대한가정학회지
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• 제48권3호
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• pp.55-69
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• 2010

A college student who exhibited several post traumatic stress disorder (PTSD) symptoms was used as a case study in order to investigate the therapeutic effects of sandplay therapy for PTSD sufferers. In total, 27 sessions of the sandplay treatment program were used to conduct psychological tests before and after the sessions. Any changes in the manner of expressions on the sand box during the treatment, and the results of pre and post psychological tests on aspects of depression, anxiety and interrelationships were analyzed. Overall results showed that the subject exhibited progressive behavioral improvement and signs of recovery. Psychological tests revealed reduced levels of depression and anxiety, and improved interrelationship scores. In conclusion, sandplay therapy does exhibit positive benefits as an effective treatment modality for PTSD in adolescents and young adults.

• 한국환경농학회지
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• 제20권2호
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• pp.93-98
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• 2001

저온에 내성인 자포니카의 일품벼와 감수성인 인디카의 태백벼 품종간에 저온처리기간 동안 및 저온처리 후 회복동안에 나타날 수 있는 생리적 반응을 비교하였다. $5^{\circ}C$의 저온처리 3일 동안에 잎의 생체중 및 엽록소 함량은 두 품종간에 차이가 적거나 없었으나 저온처리 후 $25^{\circ}C$에 회복시킨 동안에는 태백벼에 비해 일품 벼가 더 빨리 회복되었다. 상대적 수분함량, 지질과산화 작용의 지표인 malondialdehyde 생성량 및 엽록소 형광은 저온처리기간 동안 및 저온처리 후 회복기간동안에도 두 품종간에 유의적인 차이를 보였고, 이들 생리적 지표들은 생체중 및 엽록소 함량보다는 더 민감한 생리적 지표이었다. 두 품종간에 상대적 수분함량, malondialdehyde 생성량 및 엽록소 형광의 차이는 저온처리 후 회복기간동안보다는 저온처리동안에서 더 적었다. 따라서 이들 결과를 통해서 볼 때 상대적 수분함량, malondialdehyde 생성량과 엽록소 형광은 저온에 내성을 선발하는데 중요한 생리적 지표로 이용할 수 있으리라 생각한다.