• 한국음향학회지
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• 제32권1호
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• pp.56-63
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• 2013

본 논문에서는 청소년들의 MP3 사용 실태와 그에 따른 청력역치를 평가했다. 청소년들의 MP3 사용률은 지속적으로 증가하고 있으며 청력과 관련하여 위험요소가 되고 있다. 본 연구에서는 광주 지역의 2개 고등학교에 재학 중인 남녀 538명을 대상으로 MP3의 사용 실태를 조사하고 청력 역치를 측정하여 사용 유형별로 상관성을 평가했다. 분석 결과, 하루중 1시간 이상 MP3 사용률이 61.1%였으며, 주당 4일 이상 사용하는 비율이 71.6%이고, 3년 이상 사용한 경우가 36.7%로 나타났다. 조사대상의 51%가 볼륨 크기를 60%이상으로 듣고 있으며 귀 통증을 인식하고 있었다. MP3를 장시간 사용하며 소리를 크게 듣는 청소년과 그렇지 않은 청소년들의 청력은 유의한 차이가 있는 것으로 나타났다 (p< 0.0001).

• 대한통합의학회지
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• 제6권1호
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• pp.25-33
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• 2018

Purpose : The present study aimed to investigate the of the based on their oral health status and the study findings will provide the basic data for establishing future oral health related policies for the elderly. Methods : A total of 50 elderly participants were selected for the study. Oral examinations were performed by a single trained dental hygienist, the oral health status was classified according to the use of dentures, presence of temporo-mandibular joint (TMJ) noise, presence of TMJ pain, presence of trismus, presence of preferred chewing, and number of residual teeth. An oral health-related survey using the in-person interview method was conducted by two dental hygienists and 30 types of foods were selected for the assessment of chewing ability. For data analysis, the Mann-Whitney U test and Spearman's Rho analysis were performed to investigate the association between oral health status and chewing ability. Result : The results of the present study revealed that there was a statistically significant positive (+) correlation between the number of residual teeth and chewing abilities. In other words, as the number of residual teeth increased, chewing ability increased as well, with the differences being statistically significant. Conclusion : Improvement of oral health in the elderly is a fundamental aspect of healthy aging. Therefore, the implementation of more efficient oral health care policies for the elderly is required as We move toward a super-aged society.

• 천문학회보
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• 제38권2호
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• pp.38.2-38.2
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• 2013

Several studies have reported the presence of sodium excess objects having neutral atomic absorption lines at $5895{\AA}$ (NaD) and $8190{\AA}$ that are deeper than expected based on stellar population models that match the stellar continuum. The origin of these lines is therefore hotly debated. van Dokkum & Conroy proposed that low-mass stars (0.3M) are more prevalent in massive early-type galaxies, which may lead to a strong NaI 8190 line strength. It is necessary to test this prediction, however, against other prominent optical line indices such as NaD, Mgb, and Fe5270, which can be measured with a significantly higher signal-to-noise ratio than NaI 8190. We identified a new sample of roughly one thousand NaD excess objects (NEOs; ~8% of galaxies in the sample) based on NaD line strength in the redshift range 0.00${\alpha}$-enhanced" ([${\alpha}/Fe$] ~ 0.3), "metal-rich" ([Z/H] ~ 0.3), and, especially, "Na-enhanced" ([Na/Fe] ~ 0.3).

• 환경영향평가
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• 제23권6호
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• pp.517-526
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• 2014

본 연구는 객관적 방법으로써의 계층분석법(AHP)를 사용하여 최적의 철도사업의 노선선정에 있어서 필요한 환경 평가에 대한 중점항목의 가중치를 제시하여, 환경친화적인 노선 선택을 위한 정량적 기준을 제공하고자 하였다. AHP는 계층구조로 복합적인 선택 기준을 가진 각 기준들의 상대적 중요도를 평가하고, 대안들의 전체적인 우선 순위를 결정하는 의사결정의 접근법이다. 본 연구의 목적을 위해, 각 분야별 환경영향평가 검토를 담당하는 전문가 설문에 기초하여 철도사업 노선선정에 있어서 주요 환경평가 항목의 순위와 가중치를 정립하였다. 그 결과, AHP에 의한 가중치는 동 식물상, 지형 지질, 자연환경자산, 소음 진동, 수질, 위락 경관, 대기질 등 자연생태분야가 높게 나타났다. 보다 효율적인 환경친화적 노선 선정 체계를 개발하기 위해서는 환경적인 측면에 더불어, 기술적, 경제적, 사회적 측면도 고려되어야 할 것이다.

• 동의생리병리학회지
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• 제16권2호
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• pp.403-407
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• 2002

The objective of this study is to establish the new evaluating method of tinnitus and to evaluate the effect of acupuncture therapy. Fourteen patients with tinnitus were studied. The patients answered the questionnaire designed to identify and describe the subjective symptoms of tinnitus and discomfort in daily life due to tinnitus. After acupuncture therapy, the survey was conducted again among the patients and we evaluated the difference between pre-acupuncture therapy and post-acupuncture therapy. 1. Precipitating factors of tinnitus among the patients group consisted of 14 members were stress, noise, drug, overwork, URI, and otitis media in order. 2. Significant improvements in subjective symptoms of tinnitus and discomfort in daily life after acupuncture therapy were identified among the patient group of 14 members 3. Patient group of 14 members were divided into 2 groups by digestion status: patients who have poor digestion and patients who have good digestion. The patients who have good digestion showed significant improvement both in subjective symptoms of tinnitus and in discomfort in daily life after acupuncture therapy. 4. Patient group of 14 members were divided Into 2 groups by urination and defecation status: patients who have poor urination and defecation and patients who have good urination and defecation. The patients who have good urination and defecation showed significant improvement both in subjective symptoms of tinnitus and in discomfort in daily life after acupuncture therapy. 5. Patient group of 14 members were divided into 2 groups by sleeping status: patients who sleep well and patients who don't sleep well. The patients who sleep well showed significant improvement both in subjective symptoms of tinnitus and in discomfort in daily life after acupuncture therapy. This study shows that the subjective symptoms of tinnitus and discomfort in daily life due to tinnitus are involved in urination and defecation factor, sleep factor, and digestion factor. This study also shows that acupuncture therapy is effective in improving the subjective symptoms of tinnitus and discomfort in daily life due to tinnitus.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2011년도 한국우주과학회보 제20권1호
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• pp.23.4-23.4
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• 2011

MIRIS is the main payload of the Science and Technology Satellite-3 (STSAT-3). which is being developed by KASI for infrared survey observation of the Galactic plane at Paschen alpha wavelength. Wideband filters in I and H band will also be used to observe cosmic infrared background. The MIRIS will perform astronomical observations in the near-infrared wavelengths of 0.9~2 ${\mu}m$ using a 256 ${\times}$ 256 Teledyne PICNIC FPA sensor providing a 3.67 ${\times}$ 3.67 degree field of view with a pixel scale of 51.6 arcsec. The flight model of the MIRIS has been recently developed, The system performance tests have been made in the laboratory, including opto-mechanics test, vibration test, thermal vacuum test and passive cooling test down to 200K, using a thermally controlled vacuum chamber. Several focus tests showed good agreements compared to initial design parameters. Recent efforts are being concentrated to improve the system performances, particularly to reduce readout noise level in electronics. After assembly and integration into the satellite bus, the MIRIS will be launched in 2012.

• 한국가스학회지
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• 제11권1호
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• pp.1-8
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• 2007

본 논문에서는 메탈화이버를 이용한 난류예혼합 플랫버너를 제작하여 다양한 연소조건하에서 화염의 안정화범위를 확인하였으며, 연료유량과 공기유량의 변화에 따른 균일가열 능력과 배기가스 특성에 관한 실험을 실시하였다. 그리고 화염의 안정성 평가를 위한 실험을 통해 화염을 공기유량 변화에 따라 청녹염, 복사염, 청염 영역으로 나눌 수 있었고, 이들 영역은 청염>복사염>청녹염 영역 순으로 연소상태가 양호하였다. 공기비에 따른 영향을 살펴보면, 본 실험에서는 연료유량 1과 4l/min에서는 공기비 ${\alpha}=1.5$가 적합하였으며 연료유량 2l/min에서는 ${\alpha}=2.0$이 적합한 것으로 나타났다. 한편 연료유량과 관계없이 공기비 ${\alpha}=1.3{\sim}2.1$범위에서는 연소소음이 발생했다.

• Environmental Analysis Health and Toxicology
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• 제14권4호
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• pp.175-187
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• 1999

To investigate the risk perception of environmental issues, two consequtive surveys were conducted to environmental professionals using a standardized questionnaire from September to October in 1999. The number of subjects were 72 for the first survey and 68 for the second one. The questionnaire was consisted of items such as the degree of environmental pollution in Korea, risk perception of some issues on human health and ecosystem, and seriousness of the problems in the real situation in Korea. For the degree of environmental pollution in Korea, the average risk rating in the second test (7.4 point) was significantly higher than that in the first test (7.2 point). The risk perception on the general human health and ecosystem, and the seriousness in Korea situation were analyzed in the order of ′air pollution′, ′water pollution′,′soil contamination′,′waste′,′toxic chemical pollutants′,′food contamination′,′ocean contamination′, ′odor pollution′, and ′noise pollution′. Also ′toxic chemical pollutants′ problem was perceived to be the highest risk on general human health or ecosystem, and on present situation in Korea. ′Automotive vehicle exhaust′ problem was perceived to be the most severe environmental problems among specific 30 items. ′Industrial source air pollution′,′toxic air pollutants′, and ′domestic and industrial source pollutants to surface water′ were relatively severe environmental problems comparing to other problems. The pollution issues were classified into four categories by two aspects of perception; risk in general setting and seriousness in Korea situation. If the issues were highly serious in Korea and low risk perception in general setting then it is named "the Korea-specific group". Those that were all high score in two aspects, named "the Common group". Those that were all low in two aspects, named "the Nonsignificant group". And the issues were high risk perception in general setting and low seriousness in Korean situation, named "the Latent group".

• 자원리싸이클링
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• 제23권2호
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• pp.81-89
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• 2014

화력발전소 석탄재는 2010년을 기준으로 약 850만톤, 연탄재는 약 74만톤 배출된다. 이는 대량 재활용되지 않아 경제적, 환경적으로 부담이 되고 있는 실정이므로, 석탄 연소부산물의 자원화기술개발이 시급하다. 석탄 연소부산물을 균질하게 가공하는 분쇄 및 선별 등의 자원처리기술을 적용하고, 석탄 연소부산물의 품질을 관리하여, 비소성 그린시멘트인 지오폴리머의 원료로 재활용하고자 본 연구에서는 석탄 연소부산물의 지오폴리머 원료화 기술에 대한 특허와 논문을 분석하였다. 분석범위는 1979년 ~ 2013년까지의 미국, 유럽연합, 일본, 한국의 등록/공개된 특허와 SCI 논문으로 제한하였다. 특허와 논문은 키워드를 사용하여 수집하였으며, 기술의 정의에 의해 필터링하였다. 특허와 논문의 동향은 연도, 국가, 기업, 기술 등에 따라 분석하여 고찰하였다.

• Safety and Health at Work
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• 제2권1호
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• pp.70-82
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• 2011

Objectives: Ischemic heart disease (IHD) is a major cause of death in Korea and known to result from several occupational factors. This study attempted to estimate the current magnitude of IHD mortality due to occupational factors in Korea. Methods: After selecting occupational risk factors by literature investigation, we calculated attributable fractions (AFs) from relative risks and exposure data for each factor. Relative risks were estimated using meta-analysis based on published research. Exposure data were collected from the 2006 Survey of Korean Working Conditions. Finally, we estimated 2006 occupation-related IHD mortality. Results: For the factors considered, we estimated the following relative risks: noise 1.06, environmental tobacco smoke 1.19 (men) and 1.22 (women), shift work 1.12, and low job control 1.15 (men) and 1.08 (women). Combined AFs of those factors in the IHD were estimated at 9.29% (0.3-18.51%) in men and 5.78% (-7.05-19.15%) in women. Based on these fractions, Korea's 2006 death toll from occupational IHD between the age of 15 and 69 was calculated at 353 in men (total 3,804) and 72 in women (total 1,246). Conclusion: We estimated occupational IHD mortality of Korea with updated data and more relevant evidence. Despite the efforts to obtain reliable estimates, there were many assumptions and limitations that must be overcome. Future research based on more precise design and reliable evidence is required for more accurate estimates.