• Journal of Preventive Medicine and Public Health
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• 제30권3호
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• pp.599-608
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• 1997

6명의 20대 여성을 대상으로 VDT작업으로 인한 조절반응 및 동공대광반사의 작업부과에 따른 변화와 다른 사무작업을 부과할 때와의 차이를 보았다. 그 결과 다음과 같은 결과를 얻었다. 1. VDT작업에서 작업부과 시간이 증가함에 따라 조절 수축속도가 감소했으며 1시간의 휴식시간 후에는 현저하게 증가했고 다시 작업을 부과함에 따라 감소하는 경향을 보였다. 조절 수축속도의 변화보다는 뚜렷하지 않지만 이완속도도 VDT작업부과에 따라 감소되고 휴식에 의한 회복되는 경향을 보였다. 2. 일반 사무작업과 근거리 사무작업에서는 조절 수축속도에서 VDT작업부과때와 같은 반응은 보이지 않았으며, 근거리 사무작업에서 이완속도가 작업부과에 따라 감소하였으나 휴식 후 회복되지 않았다. 3. 동공대광반사에서 최초동공직경, 최초동공면적은 VDT작업에서만 작업시간의 증가에 따라 유의한 감소를 보였는데 휴식 후 회복되지 않았다. 이러한 결과는 조절 수축속도의 변화, 조절 이완속도, 동공직경과 면적의 변화가 VDT작업의 특성을 연구하는데 사용될 가능성을 보여주며, 이를 위해서 연구대상이 개인차, 생체리듬, 감정적 자극 등을 보정한 연구가 필요하다고 생각된다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1268-1268
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• 2001

The availability of in vivo and in sacco degradability values are limited because those methods require work with fistulated animals and are rather complicated, labour intensive and expensive. That is to say, the dynamics and logistics of the methodology result in considerable work, due to limitations on the amount of samples, number of bags that can be placed in an animal and different time intervals to perform kinetic studies. Therefore, a simpler method is necessary to estimate the degradation characteristics of the feed. In this way, near infrared reflectance spectroscopy has been used to predict degradation characteristics of forages. In other hand, the possibility of achieving successful transfer of spectra and equations between instruments is closely related. The objective of this study was to confirm the potential of NIR to optimize work conditions to avoid duplicated efforts in collaborative trials on animal feeds evaluation between research institutions. For this purpose, one set with forty hays and dehydrated forages samples from SERIDA and ten samples with the same characteristics from SIA, were be used to create a spectral database. A calibration was developed using samples from degradation essays made in SERIDA to predict dry matter and crude protein degradability. With the addition of five samples from SIA in original calibration set, the effect of different origin and location was compensated.

• Toxicological Research
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• 제28권3호
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• pp.201-207
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• 2012

In order to evaluate the physical and psychological health effects from automobile air pollution, 99 employees who worked near a main street were given a general health questionnaire, and the prevalence of their subjective complaints was measured. The collected data were classified according to gender, sleep time, degree of regular exercise, self-consciousness of symptoms, length of employment, work time, rest time, and smoking status. The results obtained were summarized as follows: The scores related to health complaints regarding physical and psychological items were higher in females than in males. THI scores were higher for the < 4 hour sleep time group. The health complaint scores for physical items were higher in the regular exercise group, whereas most scores for mental items were higher in the irregular exercise groups. The health complaints scores for physical and psychological items were higher in the unhealthy symptom group than in other groups. Those employees who had worked for > 4 years showed significantly higher rates of complaints regarding the eyes and skin. THI scores were higher for the < 6 hour working time group. The smoking group showed higher scores regarding health complaints related to physical items. The THI scores of the respiratory organs, mouth, anus, and digestive organs were significantly higher for the smoking group than for the non-smoking group. In summary, this study shows that the health complaint scores regarding physical and psychological symptoms tended to be higher among the unhealthy group, the less sleep time group, the less work time group, smokers, and females. These results can be used to improve the psychosomatic health status and working environments of employees who work near a main street.

• 방사성폐기물학회지
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• 제20권4호
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• pp.511-521
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• 2022

Decommissioning of nuclear power plants generates a large amount of radioactive waste in a short period. Moreover, Radioactive waste has various forms including a large volumes of metal, concrete, and solid waste. The disposal of decommissioning waste using 200 L drums is inefficient in terms of economics, work efficiency, and radiation safety. Therefore, The Korea Radioactive Waste Agency is developing large containers for the packaging, transportation, and disposal of decommissioning waste. Assessing disposability considering the characteristics of the radioactive waste and facility, convenience of operation, and safety of workers is necessary. In this study, the exposure dose rate of workers during the disposal of new containers was evaluated using Monte Carlo N-Particle Transport code. Six normal and four abnormal scenarios were derived for the assessment of the dose rate in a near surface disposal facility operation. The results showed that the calculated dose rates in all normal scenarios were lower than the direct exposure dose limitation of workers in the safety analysis report. In abnormal scenarios, the work hours with dose rates below 20 mSv·y^-1 were calculated. The results of this study will be useful in establishing the optimal radiation work conditions.

• Safety and Health at Work
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• 제5권1호
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• pp.1-6
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• 2014

Background: Workflow interruptions during surgery may cause a threat to patient's safety. Workflow interruptions were tested to predict failure in action regulation that in turn predicts near-accidents in surgery and related health care. Methods: One-hundred-and-thirty-three theater nurses and physicians from eight Swiss hospitals participated in a cross-sectional questionnaire survey. The study participation rate was 43%. Results: Structural equation modeling confirmed an indirect path from workflow interruptions through cognitive failure in action regulation on near-accidents (p < 0.05). The indirect path was stronger for workflow interruptions by malfunctions and task organizational blockages compared with workflow interruptions that were caused by persons. The indirect path remained meaningful when individual differences in conscientiousness and compliance with safety regulations were controlled. Conclusion: Task interruptions caused by malfunction and organizational constraints are likely to trigger errors in surgery. Work redesign is recommended to reduce workflow interruptions by malfunction and regulatory constraints.

• 대한수학회논문집
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• 제12권3호
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• pp.779-788
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• 1997

In this work, using the exact separatrix map which provides an efficient way to describe dynamics near the separatrix, we study the stochastic layer near the separatrix of a one-degree-of-freedom Hamilitonian system with time periodic perturbation. Applying the twist map theory to the exact separatrix map, T. Ahn, G. I. Kim and S. Kim proved the existence of the uniformly hyperbolic invariant set(UHIS) near separatrix. Using the theorems of Bowen and Franks, we prove this UHIS has measure zero.

• 한국안광학회지
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• 제12권3호
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• pp.125-130
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• 2007

이 논문은 중고등학생 41명(12-17세)의 근업시 자각 증상과 양안시 기능의 관계를 알아보고자 한 연구이다. CISS 설문 평가, 조절력검사, 조절 용이성검사, Negative relative accommodation(NRA)/Positive relative accommodation (PRA), 폭주 근점(NPC)검사, 사위검사, 그리고 AC/A(A, accommodation; C, convergence) 비를 측정하였다. 이들 검사의 결과는 정상 기댓값과 비교하여 정상 군과 이상 군으로 분류하였다. 폭주 부족보다는 조절 부족이 더 많았고 외사위보다는 내사위가 많았다. NRA/PRA는 높게 나타났고 AC/A 비는 낮게 나타났다. CISS 검사 결과는 다음과 같다; 근업시 가장 흔한 증상은 피로감이었고, 전체 증상의 점수에 대한 평균은 $16.63{\pm}7.49$이었고, 평균적인 증상의 수는 $10.07{\pm}3.04$이었고 중증 증상 수의 평균은 $1.98{\pm}2.13$이었다. 증상의 점수, 증상의 수, 증상의 심한 정도에 따라 4개의 그룹으로 분류한 후 양안시 검사의 결과와 비교하여 상관성을 분석하였다. 그룹과의 상관성은 NRA가 가장 높게 나타났고 증상의 점수는 조절 용이성, 증상의 수는 NRA, 그리고 중증 증상의 수는 근거리 사위 량이 가장 높게 나타났다. NRA는 근업 증상과 관련하여 모든 부분에서 가장 상관성이 높은 것을 보여주었다.

• 한국안광학회지
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• 제16권1호
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• pp.75-81
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• 2011

목적: 38세 이상 50세 미만의 초기노안자 52명을 대상으로 1차시기(08:00~10:00), 2차시기(13:00~15:00), 3차시기(18:00~20:00)에 걸쳐 조절기능의 일일변화를 조사하였다. 방법: 초기노안자 52명(남 30명, 여 22명)을 근거리 작업량에 따라 4군(I군: ${\geq}$ 7 hrs~IV군: < 3 hrs)으로 분류하여 조절력, 조절용이성, 상대조절력을 검사하였다. 결과: 조절력은 하루 일과 중 근업이 가장 많은 I군에서 가장 낮은 것으로 측정되었고, 단안과 양안의 조절력은 I군~IV군 모두 2차시기의 조절력이 가장 높았다. 조절용이성에서 I군의 단안과 양안, II군의 단안 그리고 III군의 단안과 양안은 2차시기가 가장 높았고, II군의 양안과 IV군의 단안과 양안은 3차시기가 가장 높은 것으로 나타났다. 허성상대조절력은 I군~IV군 모두 1차시기가 가장 높았고, 실성상대조절력의 경우 I~III군은 2차시기가, IV군은 3차시기가 가장 높은 것으로 나타났다. 결론: 작업환경 및 시간은 조절기능에 영향을 줄 수 있으므로 초기노안자의 경우 하루 일과 중 업무 시간대를 고려하여 조절기능에 대한 검사를 하는 것이 안정피로 증상을 해소하는데 도움이 될 것이다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1628-1628
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• 2001

Near infrared (NIR) spectroscopy is a powerful technique for non-destructive analysis that can be obtained in a wide range of environments. Recently, NIR measurements have been utilized as probe for quantitative analysis in agricultural, industrial, and medical sciences. In addition, it is also possible to make practical application on NIR for molecular structural analysis. In this work, Fourier transform near infrared (FT-NIR) measurements were carried out to utilize extensively in the relative amounts of different secondary structures were employed, such as Iysozyme, concanavalin A, silk fibroin and so on. Several broad NIR bands due to the protein absorption were observed between 4000 and $5000\;^{-1}$. In order to obtain more structural information from these featureless bands, second derivative and Fourier-self-deconvolution procedures were performed. Significant band separation was observed near the feature at $4610\;^{-1}$ ,. Particularly the peak intensity at $4525\;^{-1}$ shows a characteristic change with thermal denaturation of fibroin. The structural information can be also obtained by mid-IR and CD spectral. Correlation of NIR spectra with protein structure is discussed.

• 한국군사과학기술학회지
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• 제25권4호
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• pp.339-346
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• 2022

The importance of stealth technology is increasing in modern warfare, and Radar Cross Section(RCS) is widely used as an indicator of stealth technology. It is useful to measure RCS using an image-based near-field to far-field transformation algorithm in short-range monostatic conditions. However, the near-field measurement system requires a longer measurement time compared to other methods. In this work, it is proposed to reduce the measured data using an interpolation method in azimuth angular domain. The calculated far-field RCS values according to the sampling rate is shown, and the performance of the algorithm applied with interpolation in the angular domain is presented. It is shown that measurement samples can be reduced several times by using the redundancy in the angular domain while producing results similar to the conventional method.