• 대한치과의사협회지
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• 제20권3호통권154호
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• pp.233-237
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• 1982

A review of the literature was presented, illustrating the effect that gingivally retained orthodontic elastic bands have on the periodontal tissues. A case report was presented for treatment of mobile maxillary central incisors secondary to a subgingival elastic band. Following surgical removal of elastic band and periodontal debridement, the teeth were successfully retained with active orthodontic appliances. Until a harmless radiopaque medium can be safely incorporated into elastic bands, extreme caution in their use should be observed. Not only should all attempts be made to anchor the elastic bands to the clinical crown, but the patient should receive through instructions in their placement and removal.

• 산업경영시스템학회지
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• 제17권30호
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• pp.73-79
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• 1994

This paper propose Adaptive Maintenance as a new type of maintenance for machine failures which are unpredictable. A purpose of adpative maintenance is to decrease inconsistency. In order to pick up some of problems the traditional maintenance policy, We discussed Time Based Maintenance(TBM) and Condition Based Maintenance(CBM) with Bath-Tub Curve. By using Machine Condition Diagnosis Technique (CDT), Monitored condition maintenance deals with the dynamic decision making for diagnosis procedures at maintenance and caution level. Adaptive Maintenance is a powerful tool for Total Production Maintenance(TPM).

• 항공우주시스템공학회지
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• 제8권4호
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• pp.39-43
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• 2014

This paper examines the statistical process that should be performed with caution in the composite material qualification and equivalency process, and describes statistically significant considerations on outlier finding and handling process, data pooling through normalization process, review for data distributions and design allowables determination process for structural analysis. Based on these considerations, the need for guidance on statistical process for aircraft manufacturers who use the composite material properties database are proposed.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.101-102
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• 2001

Antimutagens, including diverse compounds of botanical origin, offer some promise of reducing the risk posed by exposure to mutagens. Caution is warranted, however, as there may sometimes be a delicate balance between antimutagenic effects and potentiating effects of the same compounds. We studied effects of the antimutagens spermidine (SPD) and cysteamine (CSM) on the genetic activity of the radiomimetic cancer chemotherapy drug bleomycin (BLM).(omitted)

• Annals of Occupational and Environmental Medicine
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• 제35권
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• pp.42.1-42.4
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• 2023

ChatGPT has the potential to revolutionize occupational medicine by providing a powerful tool for analyzing data, improving communication, and increasing efficiency. It can help identify patterns and trends in workplace health and safety, act as a virtual assistant for workers, employers, and occupational health professionals, and automate certain tasks. However, caution is required due to ethical concerns, the need to maintain confidentiality, and the risk of inconsistent or inaccurate results. ChatGPT cannot replace the crucial role of the occupational health professional in the medical surveillance of workers and the analysis of data on workers' health.

• Safety and Health at Work
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• 제7권4호
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• pp.381-388
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• 2016

Background: Relationships among portable scanning mobility particle sizer (P-SMPS), condensation particle counter (CPC), and surface area monitor (SAM), which are different metric measurement devices, were investigated, and two widely used research grade (RG)-SMPSs were compared to harmonize the measurement protocols. Methods: Pearson correlation analysis was performed to compare the relation between P-SMPS, CPC, and SAM and two common RG-SMPS. Results: For laboratory and engineered nanoparticle (ENP) workplaces, correlation among devices showed good relationships. Correlation among devices was fair in unintended nanoparticle (UNP)-emitting workplaces. This is partly explained by the fact that shape of particles was not spherical, although calibration of sampling instruments was performed using spherical particles and the concentration was very high at the UNP workplaces to allow them to aggregate more easily. Chain-like particles were found by scanning electron microscope in UNP workplaces. The CPC or SAM could be used as an alternative instrument instead of SMPS at the ENP-handling workplaces. At the UNP workplaces, where concentration is high, real-time instruments should be used with caution. There are significant differences between the two SMPSs tested. TSI SMPS showed about 20% higher concentration than the Grimm SMPS in all workplaces. Conclusions: For nanoparticle measurement, CPC and SAM might be useful to find source of emission at laboratory and ENP workplaces instead of P-SMPS in the first stage. An SMPS is required to measure with high accuracy. Caution is necessary when comparing data from different nanoparticle measurement devices and RG-SMPSs.

• 한국지역사회생활과학회지
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• 제13권2호
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• pp.1-11
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• 2002

This study was conducted to estimate the amounts of the electromagnetic wave penetrating from a cellular phone in a pocket of dress shirt, as well as to test how different the penetration amounts were under the conditions of wearing. It was also investigated the possibilities that the amounts of the electromagnetic wave penetrating could be decreased by using twofold pocket or electromagnetic wave free fabric. The amounts of the electromagnetic wave penetrating were measured in the following five cases; one-layered pocket with 10 different fabrics as dress shirt, a pocket adding a layer of knitted cotton, two-layered pocket with same fabric as dress shirt, two-layered pocket adding a layer of knitted cotton, and one-layered pocket adding a layer of electromagnetic wave free fabric. Each of these five cases were measured using the front and back sides of a cellular phone facing to the body. The results were as follows; 1) The amounts of the electromagnetic wave penetrating were not significantly different in 10 different fabrics and were all above the caution range (0.02mW/$cm^2$). 2) The amounts of the electromagnetic wave penetrating in cases of the back side of the cellular phone to the body, were more than in cases of the front side. 3) There is a significantly differences in part on adding a knitted under wear to one and two layers of the pocket in the case of penetration amount under the wearing conditions. 4) The amounts of the electromagnetic wave penetrating in cases of adding a layer of electromagnetic wave free fabric, were close to the safe standard value of it. The above results suggested that facing the front side of cellular phone to the body and using extra layering with some electromagnetic wave free fabrics might have some protective effects again to the penetration amounts.

• Journal of Korean Neurosurgical Society
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• 제29권9호
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• pp.1209-1214
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• 2000

Objectives : The measurement of resistance to cerebrospinal fluid outflow($R_o$) can clearly delineate cerebrospinal fluid dynamics in patients with ventricular dilatation and can help in selecting patients to undergo shunt placement. With regards to type of infusion method, bolus injection is known to be more practical and safer than continuous infusion. The purpose of this study was to obtain $R_o$ of normal adults using lumbar bolus injection method. Material and Methods : Twenty adults aged 25 to 52 years were studied using lumbar bolus injection method. Fifteen patients with hemifacial spasm and five with cerebral concussion underwent $R_o$ measurement under propofol general anesthesia and local anesthesia, respectively. Results : The mean values of $R_o$ determined 1 minute and 2 minutes after bolus injection were $4.8{\pm}1.7$ and $4.4{\pm}1.6mmHg/ml/min$, respectively. There was no significant difference of $R_o$ between propofol general anesthesia group and local anesthesia group. Two patients showed $R_o$ greater than 6mmHg/ml/min. One patient revealed unexpectedly high level of $R_o$ due to severe spinal stenosis. Conclusion : Mean Ro in this study was higher than that of Shapiro's study. Borderline Ro near 6mmHg/ml/min should be regarded with caution and compared with clinical symptoms and results of other studies. Patients with severe spinal stenosis should be evaluated with caution.

• Safety and Health at Work
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• 제1권1호
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• pp.87-97
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• 2010

Objectives: This study was conducted to investigate the effect of trust on work stress. Trust can be classified into three dimensions; social trust, institutional trust, and trust in others. The relationship between work stress and trust is regarded as having three components. First, trust has an influence on work stressors as an antecedent variable; secondly, trust modifies the effect of the various stressors, and finally, trust is one of the stressors. Methods: Data for this study was collected by interviews and self-administered structured questionnaires from 376 Korean and 77 Japanese workers in small businesses. Subjects were selected by two stage stratified random sampling from the working population of manufacturing industries. Results: Three different positions of trust are significantly related with the stress causation web. Social trust, institutional trust and trust in others significantly influence different work stressors in both Korean and Japanese workers. Three different kinds of trust influence work stressors among Korean workers, but institutional trust has no impact on work stressors among Japanese workers. As a moderating variable for perceived stress, distrust in an employer is statistically significant in both groups. However, stress symptom prevalence among Korean workers is modified by caution, trust in career development, and distrust in co-workers, but that of Japanese workers is modified only by distrust in employer. Job satisfaction of Korean workers is affected by general trust, utility of relation, institutional trust and trust in employer, but among Japanese workers, caution, reputation and trust in employer have influence on job satisfaction. Conclusion: The effect of trust on work stress, perceived stress, stress reaction and job satisfaction are different among Korean workers and Japanese workers. Three dimensions of trust have three different positions as antecedent, moderating and mediating factors in stress causation.

• 품질경영학회지
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• 제49권3호
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• pp.327-340
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• 2021

Purpose: The purpose of this study is to propose a system predicting whether an electricity distribution system is abnormal by analyzing the temperature of the deteriorated system. Traditional electricity distribution system abnormality diagnosis was mainly limited to post-inspection. This research presents a remote monitoring system for detecting thermal images of the deteriorated electricity distribution system efficiently hereby providing safe and efficient abnormal diagnosis to electricians. Methods: In this study, an object detection algorithm (YOLOv5) is performed using 16,866 thermal images of electricity distribution systems provided by KEPCO(Korea Electric Power Corporation). Abnormality/Normality of the extracted system images from the algorithm are classified via the limit temperature. Each classification model, Random Forest, Support Vector Machine, XGBOOST is performed to explore 463,053 temperature datasets. The process capability index is employed to indicate the quality of the electricity distribution system. Results: This research performs case study with transformers representing the electricity distribution systems. The case study shows the following states: accuracy 100%, precision 100%, recall 100%, F1-score 100%. Also the case study shows the process capability index of the transformers with the following states: steady state 99.47%, caution state 0.16%, and risk state 0.37%. Conclusion: The sum of caution and risk state is 0.53%, which is higher than the actual failure rate. Also most transformer abnormalities can be detected through this monitoring system.