• 상하수도학회지
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• 제28권4호
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• pp.461-472
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• 2014

The tap water plays a critical role in our daily life by providing clean water for drinking as well as for residential use. Its importance, however, is often hidden and criticized in mass media because drinking the unprocessed tap water as a primary source of drinking water is very low comparing to other countries. This is because survey tool in Korea is often different from those in other countries so their results on the tap water cannot be directly compared without analysis on survey questionnaire. Therefore, we examplified cases showing the difference of questions of each country and discussed the reason why results of tap water intake should not be compared without analysis on the questions. Also, distrust on Arisu without rational reason is known as the first reason of distrust on the tap water. However, it was not the ultimate reason of distrust on the tap water. To verify, we designed survey questions in a tricky way that the same question was asked twice with different choices in the survey questionnaire. Most of the people who distrust Arisu without rational reason at the first question were selected different choices and significantly reduced in the second question. This proved that the ratio of distrust on the tap water is not actually the right reason and that by providing more choices, people's distrust on the tap water without rational reason can turn into more specific reasons.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 춘계학술대회
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• pp.193-193
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• 2003

Recent industrial society has human widely exposed to PAHs that are coming from the incomplete combustion of organic material as widespread environmental contaminants. Biological activities of PAHs are not known although PAHs are considered as carcinogens. The mechanism of action of PAHs has been studied extensively, however it is not clear how PAHs turn on CYPlAl in human breast cancer, Our laboratory have been studied the effect of PAHs in the human breast cancer cells, MCF-7. In this study, we examined the ZR-75-1, human breast cancer cells, as a new system to evaluate bioactivity of PAHs and to compare the PAHs action with that of MCF-7 cells. ZR-75-1 human breast cancer cell line is responsible to estrogen and progesterone. We have been able to establish long term culture system of this cells then used for the study to the effect of 13 different PAHs and environmental samples. We demonstrate that PAHs induced the CYP1A1 promoter and 7-ethoxyresorufin O-deethylase (EROD) activity in a concentration-dependent manner. RT-PCR analysis indicated that PAHs significantly up-regulate the level of CYP1A1 mRNA. Some of PAHs showed stronger stimulatory effect on CYP1 gene expression than TCDD Apparently, ZR-75-1 cells have Aryl hydrocarbon receptors (AhR), therefore it would be a good experimental tool to study the cross-talk between PAHs and steroid actions.

• 한국의료질향상학회지
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• 제1권1호
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• pp.56-65
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• 1994

Total quality management has been a focus of concern in recent years since some dissatisfaction with the results from implementation of quality assurance programs in the U.S. Many managerial methodologies and innovation guidelines from academic disciplines have been applied to promote TQM programs in the health field. This paper consists of two folds of aspects: firstly to examine TQM's managerial philosophy by comparing with the newly introduced managerial concepts in Business Reengineering; and then to introduce a method for an integrative way of process analysis, Entity Life-Cycle Diagram (ELCD) modeling. The analysis method was compared with Process Map, which is a well-known method for BR applications. To show effectiveness of ELCD modeling, a case of application was introduced using 'drug' as a target entity. With having TQM issues in mind, the result was reflected in designing Entity Relation Diagrams. The results of ELCD modeling turn out to be helpful in designing database related to quality monitoring, in that many monitoring check points can be identified in a systematic way and that queries cross-sectional over organizational boundaries can be generated with a consistent view focusing on the drug use as a single process. Full evaluation of the analysis method remains to be studied until the completion of the information system under construction. But as long as TQM is based on a process-oriented view and needs supports from information system, ELCD can be one of the appropriate choice as a tool for the process analysis.

• Asian Journal of Atmospheric Environment
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• 제8권1호
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• pp.15-24
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• 2014

The capital city of Himalayan Country Nepal, Kathmandu Valley is surrounded by consecutive high mountains, which limits the air distribution and mixing effects significantly. It in turn generates steady air flow pattern over a year except in monsoon season. The air shed in the Valley is easily trapped by the surrounded mountains and the inversion layer formulated as the cap. The $PM_{10}$ concentration was noticeably higher than the standard level (120 ${\mu}g/m^3$) in urban and suburban area of Kathmandu valley for all seasons except monsoon period. The Valley area experiences similar wind patterns (W, WWS, and S) for a year but the Easterly wind prevails only during the monsoon period. There was low and calm wind blows during the winter season. Because of this air flow structure, the air emission from various sources is accumulated within the valley air, high level of air pollution is frequently recorded with other air polluted cities over the world. In this Valley area, brick kilns are recognized as the major air pollution source followed by vehicles. Mostly Bull Trench Kiln (BKT), Hoffman Kiln and Vertical Shaft Brick Kiln (VSBK) are in operation for brick firing in Kathmandu valley where the fuels such as crushed coal, saw dust, and natural gas are used for processing bricks in this study. Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts (TRACI) was used for screening and quantifying the potential impacts of air emission from firing fuels. The total Environmental Performance Score (EPS) was estimated and the EPS of coal was approximately 2.5 times higher than those of natural gas and saw dust. It is concluded that the crushed coal has more negative impact to the environment and human health than other fuel sources. Concerning the human health and environment point of view, alternative environment friendly firing fuel need to be used for brick industry in the kiln and the air pollution control devices also need to be applied for minimizing the air emissions from the kilns.

• The Journal of Advanced Prosthodontics
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• 제7권1호
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• pp.51-55
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• 2015

PURPOSE. Bone density at implant placement site is a key factor to obtain the primary stability of the fixture, which, in turn, is a prognostic factor for osseointegration and long-term success of an implant supported rehabilitation. Recently, an implant motor with a bone density measurement probe has been introduced. The aim of the present study was to test the objectiveness of the bone densities registered by the implant motor regardless of the operator performing them. MATERIALS AND METHODS. A total of 3704 bone density measurements, performed by means of the implant motor, were registered by 39 operators at different implant sites during routine activity. Bone density measurements were grouped according to their distribution across the jaws. Specifically, four different areas were distinguished: a pre-antral (between teeth from first right maxillary premolar to first left maxillary premolar) and a sub-antral (more distally) zone in the maxilla, and an interforaminal (between and including teeth from first left mandibular premolar to first right mandibular premolar) and a retroforaminal (more distally) zone in the lower one. A statistical comparison was performed to check the inter-operators variability of the collected data. RESULTS. The device produced consistent and operator-independent bone density values at each tooth position, showing a reliable bone-density measurement. CONCLUSION. The implant motor demonstrated to be a helpful tool to properly plan implant placement and loading irrespective of the operator using it.

• 전자공학회논문지
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• 제50권3호
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• pp.16-22
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• 2013

n 개의 균일한 결합선로를 해석하기 위하여 2n-port 어드미턴스 매트릭스의 추출에 기초한 일반적인 특성화 절차가 제시된다. 본 논문에서는 비대칭 다중 결합선로를 해석하기 위하여 시간영역의 유한차분법을 사용하여 정규화 모드 파라미터 접근법의 적용을 제안한다. 주파수 의존적인 정규화 모드 파라미터는 2n-port 어드미턴스 매트릭스로부터 얻어지고, 이로부터 주파수 의존적인 전파상수와 유효 유전율 및 결합선로의 특성임피던스를 계산할 수 있다. 이 기법을 설명하기 위해 몇몇의 실질적인 다중 유전체상의 결합선로 구조들이 모의 실험되었으며, 특히 전도체가 유전체 사이에 내재된 형태의 선로가 해석되었다. 시간영역 유한 차분법을 활용한 결과는 Spectral Domain Method의 모의실험 결과와 비교하였고, 잘 일치함을 보였다. 시간영역의 특성화 절차에 기인한 유한차분법은 얇거나 두꺼운 혼성 구조 뿐 아니라 다층 PCB상의 다중의 전도체 결합 선로 설계를 위한 훌륭한 광대역 모의실험 도구가 됨을 볼 수 있다.

• 한국공작기계학회논문집
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• 제16권5호
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• pp.1-6
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• 2007

This paper presents a new experimental Servo-Parameter tuning technique for a 6-axes articulated robot manipulator, especially considering robot's dynamics. First of all, investigation for proportional gain of velocity control loop by using a Dynamic Signal Analyzer(DSA) is performed. Using the FUNCTION characteristic of DSA based on the Bode plot, the Bode plot of open loop transfer function can be obtained. In turn, the integral gain of a servo controller can be found out by using the integration time constant extracted from the Bode plot of open loop transfer function. In the meanwhile, the positional gain of the servo controller can be obtained by using the Bode plot of the closed loop transfer function. Using the experimental gain tuning technique proposed in this paper, the testing linear motion of DR6-II robot has been shown to be more accurate rather than the motion with a conventional(empirical) gain tuning technique in Doosan Mecatec Co., Ltd., by improving the dynamic response of the robot as well as synchronizing each joint velocity according to the positional command of an end-effector.

• Computers and Concrete
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• 제22권1호
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• pp.27-37
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• 2018

Reinforced concrete structures are widely used in civil engineering projects around the world in different designs. Due to the great evolution in computational equipment and numerical methods, structural analysis has become more and more reliable, and in turn more closely approximates reality. Thus among the many numerical methods used to carry out these types of analyses, the finite element method has been highlighted as an optimized tool option, combined with the non-linear and linear analysis techniques of structures. In this paper, the behavior of reinforced concrete beams was analyzed in two different configurations: i) with welding and ii) conventionally lashed stirrups using annealed wire. The structures were subjected to normal and tangential forces up to the limit of their bending resistance capacities to observe the cracking process and growth of the concrete structure. This study was undertaken to evaluate the effectiveness of welded wire fabric as shear reinforcement in concrete prismatic beams under static loading conditions. Experimental analysis was carried out in order compare the maximum load of both configurations, the experimental load-time profile applied in the first configuration was used to reproduce the same loading conditions in the numerical simulations. Thus, comparisons between the numerical and experimental results of the welded frame beam show that the proposed model can estimate the concrete strength and failure behavior accurately.

• 한국정밀공학회지
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• 제30권11호
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• pp.1121-1128
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• 2013

Ultrasonic grinding system is that the ultrasonic vibration by ultrasonic actuator is applied on conventional grinding system during grinding process. The Ultrasonic vibration with a frequency of over 20kHz can reduce grinding forces and increase surface quality, material removal rate (MRR) and grinding wheel life. In addition, ultrasonic vibration assisted grinding can be used for the materials that are difficult to cut. In this paper, methodology for ultrasonic tools is studied based on finite element method, and in turn the ultrasonic tools are designed and fabricated. It is found that the ultrasonic tool can vibrate with a frequency of 20kHz and amplitude of $25{\mu}m$. In order to verify the machining performance, the grinding experiment is performed on titanium alloy. By applying ultrasonic vibration, the grinding force and temperature are reduced and MRR is increased compared with the conventional grinding.

• 복식문화연구
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• 제24권1호
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• pp.114-117
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• 2016

It is recognized that the global apparel market of the twenty-first century is largely profit driven, and that the majority of producers and retailers have sourced products from the lowest cost locations. Purchase tickets of fashion goods available from 'fast' fashion retailers (at least within the UK) refrain from providing the consumer with details of the full circumstances of production. It seems that the majority of major retailers and producers are not willing to engage in levels of self-regulation which could ensure that the products offered to consumers are ethically produced and offer acceptable levels of sustainability. Meanwhile many fashion consumers have the desire to purchase sustainable products, produced ethically by workers paid fair wages in safe working environments. Consumer demand could be a powerful tool to adjust the behaviour of manufacturers and buyers. This paper proposes the introduction of international legislation demanding greater degrees of transparency than exist currently and that the full sourcing and production details of fashion products are stated clearly on the product's purchase ticket within its retail setting. With the introduction of such legislation, consumers could thus be given the opportunity of purchasing goods which they feel accommodate their own views on ethical manufacture and sustainable products. In turn, consumer pressure could ensure indirectly that retail buyers consider all ethical and sustainable aspects of production when negotiating with garment producers/suppliers. Further to this, such a negotiating stance could ensure the improvement of the terms and conditions of employment of the numerous garment workers worldwide.