• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.1
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• pp.38-54
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• 1996

Respirator fit testing is required before entering specific work environmentals to ensure that the respirator worn satisfies a minimum of fit and that the user knows when the respirator fits properly. The fit of a respirator can be determined by qualitative (QLFT) or quantitative fit test (QNFT). The QNFT, having been universally accepted more than the QLFT, provide an objective and numerical basis by measuring a fit factor (FF). Until a few years age, only one QNFT technigue was available and accepted by U.S. Occupational Safety and Health Administration (OSHA) regulations. In the 1980's and 1990's, several new and fundamentally different QNFT methods were developed. Two of the newer methods are commercially availale and are accepted by OSHA as suitable alternatives. In this articles, the principle of operation of each ONFT technique is explained and each technique's major advantages and disadvantages are pointed out. Emphasis is given to negative-pressure air-purifying respirators, as they are in most frequent use today. The requirements and recommendations for fit testing positive-pressure respirators are discussed as well. Finally, the presently available QNFT standards and regulations are summarized to assist the user in making fit testing decisions.

• The Korean Journal of Pain
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• v.19 no.1
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• pp.1-7
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• 2006

Chronic pain can cause disability, mild to severe suffering and high medical costs. Some unfortunate patient do not improve despite administering conservative treatment and then the various interventional therapies, including oriental medical treatment and/or surgery, and they find themselves in search of a more effective pain relief. Deep dry needling is one of the newer treatment modalities for these patients. The last 10 years have seen a lot of progress in understanding the neural pathways and the type and extent of tissue involvement during chronic pain. This in turn has stimulated the development of new treatment techniques, and deep dry needling is one of them. So, the authors of this paper discuss the individual theories, the characteristics and future directions of several deep dry needling techniques, and we examine the new dry needling technique that has been recently developed in Korea.

• Korean Institute of Interior Design Journal
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• no.3
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• pp.33-37
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• 1994

Increasing interest and providing educational experience for the public have long been a major ARt Museum goal. This interest raises the question of how visitors respond to museum exhibits. Much researches have been done which indicate the newer and more interactive exhibits are indeed more didactic and enjoyable than conventional exhibits. This study examined the effectiveness of art exhibits which display information about the creative process of developing a work art along with the final work of art to test if they results in more viewer interest and greater appreciation of the final work of art than those which display only the final work of art. In the early part of the 1991 spring, a counterblancing AB/BA quasi-experiment was carried out in the Jhnson Museum of Art, Cornell University. Methods used to collect and measure visitory interest and appreciation were unobtrusive observation and survey questionnaire. As the indirect measurement of visitor interest, attracting power and holding power were measured by unobstrusive observation of visitor time spent, while the direct measurement of visitor interest and appreciation, visitor's interest, understanding , and degree of favorableness were measured by survey questinnaire. Data analysis reached conclusion that the process approach fine art exhibit designs significantly resulted in more viewer interest and greater appreciation of art work than the conventional fine art exhibit design.

• Korean Journal of Human Ecology
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• v.20 no.3
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• pp.713-729
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• 2011

The purpose of this study is to suggest an activation plan for community centers. The community centers, categorized into 3 types by the number of visitors, were comparatively analyzed by their programs, operation, and visitors' opinion. 6 community centers in Heungduk-gu, Cheongju-city, their 6 operators, and their 220 visitors were the sample. This study surveyed community centers on the spot about their space characteristics and programs, interviewed operators, and asked questionnaires to visitors. The data of the 3 categorized centers were analyzed by frequency, average, and percentage. The following is the result: 1) The number of visitors was dependent on the type of residence and age of the residents. The activated community centers were found in residence type apartment blocks, and with an age group in its 40s. 2) The space satisfaction was dependent on the year of construction; it was higher with newer buildings and wider sizes. 3) All the centers were affirmative on the communication of the participants of programs. In conclusion, the activation plan of the community center has to comprise a renovation of old buildings, public promotion, and the development of programs taking into consideration the age group of the residents.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.464-466
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• 2011

This technical paper presents a new solid propellants family. The views are based on open literature and patents recently. Electrically controlled extinguishable solid propellants (ESCSP) are capable of multiple ignitions, extinguishments and throttle control by the application of electrical power. Both core and end burning no moving parts ECESP grains/motors to three inches in diameter have now been tested. Ongoing research has led to a newer family of even higher performance ECESP providing up to 10% higher Isp, manufacturing ease, and significantly higher electrical conduction.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.473-478
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• 2016

Hepatocellular cancer is a very common cause of cancer related deaths worldwide. Only 30-40% of patients present with early-stage disease open to curative treatments, such as resection or transplantation, while others can only undergo local therapies or palliative care. Various trans-arterial approaches have been used for treatment of hepatocellular carcinoma in patients who need a down-staging to liver transplantation, and who are not candidates for transplantation or radiofrequency ablation. Transarterial chemoembolization (TACE), transarterial embolization (TAE), drug-eluting beads, and radioembolization have been used for locoregional control, and have been shown to prolong the overall survival when compared with supportive care. In this review, we discuss patient selection, pre- and post-procedure imaging, techniques, safety, and clinical outcomes related to these therapies. Newer advances with future directions in various fields related to trans-arterial therapies are also discussed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.4759-4763
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• 2014

Radiation therapy in ovarian cancers has been considered an outdated concept for many years, mainly due to its toxicity and failure to show benefit in terms of survival. Chemotherapy has been extensively used after surgery for these cancers and it has almost replaced radiation therapy as an adjuvant treatment. Nevertheless, failures in ovarian cancers continue to occur even with the use of newer and effective chemotherapy regimens. About 70% patients demonstrate recurrence in the abdomen or pelvis after first line chemotherapy in ovarian cancers. With advances in technology and sophistication of radiation techniques, along with the molecular and biological knowledge of distinct histological subtypes, there is a need to redefine the role of radiation therapy. This review article focuses on the literature on use of radiation in ovarian cancers and its rationale and indications in the present day. For this, a literature pub med/medline search was performed from January 1975 to March 2014 to redefine the role of radiotherapy in ovarian cancers.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.4
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• pp.179-187
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• 2019

This study aims to investigate the effects of market commonality and resource similarity on price competition and the recursive consequences in the Korean lodging market. Price comparison among hotels in the same geographic market has been facilitated through the development of information technology, rendering little search cost of consumers. While the literature implies the heterogeneous price attack and response among hotels, a limited number of empirical researches focus on the asymmetric and recursive pattern in the competitive dynamics. This study empirically examines the price interactions in the Korean lodging market based on the theoretical framework of competitive price interactions and countervailing power. Demonstrating superiority to the spatial lag model and the ordinary least squares in the estimation, the results from spatial error model suggest that the hotels with longer operational history pose an asymmetric impact on the price of the newer hotels. The asymmetry is also found in chain hotels over the independent, further implying the possibility of predatory pricing. The findings of this study provide the evidence of a hierarchical structure in the price competition, with different countervailing power by the resources of the hotels. Theoretical and managerial implications are discussed, with suggestions for future study.

• Environmental Engineering Research
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• v.21 no.2
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• pp.132-139
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• 2016

In early 90s the worldwide awareness about the energy crisis and global warming had been increased and emission reduction (by improving energy efficiency), as well as increasing the capacity of clean and renewable energies, showed themselves as the most important steps towards the sustainable development approach. However, investigations on Iran's environmental situation show huge decline in recent decades and apparently there is no sense of urgency about these issues through the vision of Iranian politicians. In this article the idea of replacing the old gas turbines of Polkalleh natural gas compressor station - as one of the main compressor stations of Iran - with newer and more efficient gas turbines is evaluated, emphatically for reducing greenhouse gases emissions and their environmental costs and decreasing natural gas consumption as well. Clearly such idea is costly, but analyzing its economic impacts, huge declines in annual costs and greenhouse gases emissions can be seen as well. So an investment about $95 million can decrease 40% of Polkalleh compressor station annual costs, 25% of natural consumption and 30% of $CO_2$ and $NO_x$ emissions. Besides the simple payback period of this investment is about 2.5 years from the cut-expenses of annual costs.

• International Journal of Vascular Biomedical Engineering
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• v.3 no.1
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• pp.1-5
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• 2005

Background: Coronary atherosclerosis artery disease is the leading cause of morbidity and mortality. Coronary artery bypass grafting (CABG) which utilizes the saphenous vein graft, has helped in alleviating the suffering of these patients. Newer techniques are being developed to improve upon the techniques. Still there is significant number of failures, leading to re-grafting or re-vascularization. Some studies have helped in identifying the high and low shear stress regions. Further studies based on their realistic models are required. Material, methods and results: we developed the realistic model of fully blocked right coronary with bypass graft placed at angle of $5^0$ with curvature similar to that of artery. Pulsatile flow of birefringent solution through this model by polarized light was visualized. The images of complete flow field in the model were recorded and analyzed. Regions of high flow disturbances which are prone to further changes are identified. Existence of recirculation in the blocked coronary may initiate new blood-tissue interactions deleterious to bypass graft. Conclusion: Our study shows that by selecting the procedure to place bypass graft at minimum angle with curvature similar to that of artery and smooth sutures may improve the life span of the graft. This study also identified that coronary blocked regions contributing by recirculation flow at the proximal and distal regions of bypass which may require further studies.