• Wind and Structures
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• 제14권6호
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• pp.499-515
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• 2011

Low-frequency building vibration is known to induce symptoms of motion sickness in some occupants. This paper examines how the adoption of a theory of motion sickness, in conjunction with a dose-response model might inform the real-world problem of managing and designing standards for tall building motion sway. Building designers require an understanding of human responses to low-dosage motion that is not adequately considered by research into motion sickness. The traditional framework of Sensory Conflict Theory is contrasted with Postural Instability Theory. The most severe responses to motion (i.e., vomiting) are not experienced by occupants of wind-excited buildings. It is predicted that typical response sets to low-dosage motion (sleepiness and fatigue), which has not previously been measured in occupants of tall-buildings, are experienced by building occupants. These low-dose symptoms may either be masked from observation by the activity of occupants or misattributed to the demands of a typical working day. An investigation of the real-world relationship between building motion and the observation of low-dose motion sickness symptoms and a degradation of workplace performance would quantify these effects and reveal whether a greater focus on designing for occupant comfort is needed.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.447.2-447
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• 2001

• Imaging Science in Dentistry
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• 제31권3호
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• pp.165-173
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• 2001

Objectives : To evaluate the absorbed and effective doses of spiral and computed tomography for the dental implant planning. Materials and Methods: For radiographic projection, TLD chips were placed in 22 sites of humanoid phantom to record the exposure to skin and the mean absorbed dose to bone marrow, thyroid, pituitary, parotid and submandibular glands and nesophagus. Effective dose was calculated, using the method suggested by Frederiksen et al.. Patient situations of a single tooth gap in upper and lower midline region, edentulous maxilla and mandible were simulated for spiral tomography. 35 axial slices (maxilla) and 40 axial slices (mandible) with low and standard dose setting were used for computed tomography. All the radiographic procedures were repeated three times. Results: The mean effective dose in case of maxilla was 0.865 mSv, 0.452 mSv, 0.136 mSv and 0.025 mSv, in spiral tomography of complete edentulous maxilla, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). That in case of mandible was 0.614 mSv, 0.448 mSv, 0.137 mSv and 0.036 mSv, in spiral tomography of complete edentulous mandible, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). Conclusions: Based on these results, it can be concluded that low mAs computed tomography is recommended instead of spiral tomography for the complete edentulous maxilla and mandible dental implant treatment planning.

• Journal of Radiation Protection and Research
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• 제31권2호
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• pp.53-63
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• 2006

원전 종사자를 대상으로 경시적인 코호트 연구를 통하여 저준위 방사선 노출과 암 발생 위해도를 규명하고자 하였다. 방사선 노출에 관한 정보는 한국수력원자력(주)의 방사선 관리 DB에서 수집하였고, 암 발생에 관한 정보는 한국인 중앙 암 등록 자료를, 암 사망에 관한 정보는 통계청 사망원인 자료를 이용하여 수집하였다. 방사선 노출과 암 발생 위해도는 표준화 암 사망비(SMR)와 표준화 암 발생 비(SIR)로 평가하였다. 노출 군에서 암 발생에 대한 상대위험도는 1.08로 평가되었으나 전체 암에 대한 SIR은 0.81로 유의성이 관찰되지 않았다. 암 사망에 대한 상대위험도는 1.21 이었으나 전체 암에 대한 SMR도 0.86으로 역시 유의성은 관찰되지 않았다. 암 유형별 양상은 우리나라 일반인과 유사한 결과를 보였으며, 방사선량 증가에 따른 양-반응 관계 또한 확인되지 않았다.

• 대한방사선치료학회지
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• 제9권1호
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• pp.106-112
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• 1997

MDCK 세포를 한국 세포주 은행으로부터 분주 받아 배양한 후 저선량 gamma선 조사에 대한 세포수준에서 방사선 효과를 알아보기 위하여 세포 증식능의 변화, Superoxide dismutase(SOD)와 catalase, FOX I의 함량 변화를 측정 검토하였다. 그결과, 저선량의 방사선를 조사했을 때, 세포의 증식능은 방사선 조사후 2시간에서 10 cGy는 $95.1\%$, 50cGy는 $96.4\%$로 대조군보다 약간의 감소가 나타났으나, 24시간 후에서 10cGy는 $96.7\%$, 50cGy는 $73.1\%$로 선량이 증가함에 따라 세포 증식능은 감소하였다. 저선량 조사에 의한 MDCK 세포의 SOD 활성도는 전반적으로 증가하였고, Mn-SOD 활성 역시 증가하였다. 세포 내의 $H_{2}O_2$의 양을 측정한 FOX I에서 선량이 증가함에 따라 감소하였으며 catalase 효소의 함량은 대조군보다 증가되는 경향을 보였다. 이와 같은 결과로 볼 때 저선량 방사선 조사에 대한 효과는 세포내부의 자체적인 방어기작의 발현으로 인한 결과라고 생각된다.

• 한국방사선학회논문지
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• 제16권5호
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• pp.519-526
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• 2022

능동형 전자식 개인피폭선량는 개인의 피폭 선량을 실시간으로 확인할 수 있는 장점을 가진 보조선량계이다. 하지만 국내에 사용되고 있는 다수의 능동형 개인피폭 선량계는 의료기관에서 사용하는 진단방사선 영역에서 큰 오차와 낮은 응답성을 가진다. 이에 본 연구에서는 Si 포토다이오드 검출기를 사용하는 능동형 전자식 개인선량계에서 저에너지 영역의 응답특성을 향상시키기 위한 에너지 보상 두께를 평가하였다. 40 kVp에서 80 kVp 영역에서는 Al 0.2 mm + Sn 1.0 mm 필터에서 우수한 응답특성을 보였고 80 kVp에서 120 kVp 영역에서는 Al 0.2 mm + Sn 1.6 mm 필터에서 우수한 응답특성을 보였다.

• 대한족부족관절학회지
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• 제26권4호
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• pp.177-182
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• 2022

Purpose: The efficacy and safety of low-dose pregabalin and alpha lipoic acid in diabetic neuropathy were evaluated and analyzed. Materials and Methods: This study designed a retrospective study that included patients with diabetic neuropathic pain. From 2009 to 2022, 100 patients who suffered from diabetic neuropathic pain were included in this study. The patients were divided into group I (pregabalin 150 mg/day with alpha lipoic acid 600 mg/day) and group II (pregabalin 300 mg/day with alpha lipoic acid 600 mg/day). The visual analogue scale (VAS), medication side effects, and neurometer results were compared. Results: The mean follow-up period of the above patients was 120.23 weeks in group I and 149.05 weeks in group II. The average VAS score in group I decreased by 3.23 points, and the average VAS score in group II decreased by 2.86 points. Approximately 24.3% of group I had side effects, such as dizziness, sleepiness, and gastrointestinal trouble, while 76.7% of patients in group II had side effects. Sixtyseven patients had a neurometer examination before and after the medication, and there is no statistical difference between the two groups. Conclusion: The combination of low-dose pregabalin (pregabalin 150 mg/day) and alpha lipoic acid in diabetic neuropathy had a similar clinical effect and less frequent medication side effects than regular dose pregabalin (pregabalin 300 mg/day) and alpha lipoic acid. Therefore, low-dose pregabalin (pregabalin 150 mg/day) and alpha lipoic acid should be considered in treating diabetic neuropathy.

• Journal of Nutrition and Health
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• 제26권6호
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• pp.672-679
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• 1993

This study was designed to determine changes of serum glucose and lipid levels in noninsulin dependent diabetes mellitus patients during different doses of docosahexaenoic acid (DHA)-rich fish oil supplementation. All patients had a fasting blood glucose of less than 180mg/dl, a LDL-cholesterol of less than 160mg/dl, and a triglyceride of more than 160mg/dl. None had clinical evidence of renal, hepatic or coronary vascular disease. Sixteen patients served as control. Seven patients ingested 2.00g of fish oil(low dose group), consisting of 0.30g eicosapentaenoic acid(EPA) and 0.55g DHA. The group of modest dose(n=9) was provided 3.91g of fish oil, consisting 0.59g EPA and 1.08g DHA. After 4 weeks, serum triglyceride concentration showed a mild but nonsignificant elevation in control group, a 9% decrease(194 to 177mg/dl) in the group of low dose of fish oil and a 28% decrease(206 to 161mg/dl) in the group of modest dose. The level of high density lipoprotein(HDL), HDL2, HDL3 and total cholesterol in all groups were not changed. There was a mild increase in malondialdehyde and low density lipoprotein(LDL)-cholesterol concentration and decrease in $\alpha$-tocopherol concentration. However, these changes were not significant.

• Nuclear Engineering and Technology
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• 제52권8호
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• pp.1807-1816
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• 2020

In this work, a Gaussian Process (Kriging) approach is proposed to provide efficient dose mapping for complex radiation fields using limited number of responses. Given a few response measurements (or simulation data points), the proposed approach can help the analyst in completing a map of the radiation dose field with a 95% confidence interval, efficiently. Two case studies are used to validate the proposed approach. The First case study is based on experimental dose measurements to build the dose map in a radiation field induced by a D-D neutron generator. The second, is a simulation case study where the proposed approach is used to mimic Monte Carlo dose predictions in the radiation field using a limited number of MCNP simulations. Given the low computational cost of constructing Gaussian Process (GP) models, results indicate that the GP model can reasonably map the dose in the radiation field given a limited number of data measurements. Both case studies are performed on the nuclear engineering radiation laboratories at the University of Sharjah.

• Nuclear Engineering and Technology
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• 제30권4호
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• pp.308-317
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• 1998

Ensuring occupational radiation exposure(ORE) as low as is reasonably achievable(ALARA) has been one of very important requirements in a nuclear power plant. It is well known that about 70 percent of occupational dose has incurred from maintenance jobs in the outage period. To reduce occupational dose effectively, the high-dose jobs in the outage period should be identified with their dose reduction potentials and methods. In this study, a PC-based ORE database program, INSTORE, is developed to evaluate ORE doses in individual jobs, and the ORE data of Kori Units 3 and 4 are assembled to the database. Based on customary job classification, radiation work is classified into 26 main jobs which comprise 61 detailed jobs, and occupational doses are assessed according to each detailed job. As a result, high-dose jobs are identified with dose reduction priority in terms of collective ORE dose. It is recommended that adeqaute dose reduction methods for these jobs should be prepared to improve their working conditions and procedures.