• Journal of Korean Ophthalmic Optics Society
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• v.6 no.2
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• pp.77-80
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• 2001

The purpose of this work is that by using speckle phenomena of low-level He-Ne laser, it analyzes the movement condition of surface elements on a substance vibrating. The lights from laser reflect against a copper plate and will be shown as speckles on a vibration board. If we vibrate these speckles by sound waves of a speaker installed on the back, the speckles change with various shapes. When a vibration board has a maximum vibration, the frequency becomes a dynamical resonance frequency and we can mark the changes of speckles at that time on a vibration board.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.1
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• pp.57-61
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• 1999

This is a study of measurement of inter Reading Pupillary Distance (P.D.) in 729 old aged farmers (aged over 50). The average of Reading Pupillary Distance (P.D.) in man (58.93mm) is bigger than in woman (57.82mm), and the O.C. of Ready-made Reading Spectacles is 68.98mm.

• Journal of Korean Ophthalmic Optics Society
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• v.2 no.1
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• pp.103-110
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• 1997

This work presents experimental results on the electrical properties of hydrogenated amorphous carbon films(a-C : H) prepared by PECVD. Conductance of a-C: H was measured as a function of temperatures in the range of 100 to 423K. We studied two a -C: H films: one was well explanied by the Mott's variable range hopping(VRH) rule. But the other sample did not follow it. The conduction data of second sample were well fitted to Shimakawa's multi-phonon hopping(MPH) model according to which conductivity is proportional to Tm with m= 15~17. But, in our samples, m was 10~12.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.313-315
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• 1997

We developed a new analysis technique for the assessment of irregular vibratory movement of vocal folds. Successive frames of pre-recorded video images from videostroboscopy were transferred to computer memory and a vibratory tract of one selected point was described as a waveform by displaying the same lines of all frames along the y-direction. By applying this technique, irregular vibratory patterns of multiple regions, such as asynchronized registration of glottal cycles, could be easily visualized. It would be possible to monitor and analyze the pathologic changes of vocal fold movement by means of this newly developed system.

• Imaging Science in Dentistry
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• v.34 no.2
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• pp.107-110
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• 2004

A case of sialadenitis is presented in a patient with painful swelling of the right mouth floor. The condition was caused by trauma on the right mouth floor during dental treatment, which had happened 15 days before admission. On aspiration, mucous secretion was found and ultrasonography showed obstruction of duct. Histopathological studies and surgical investigation established a definite diagnosis of obstructive sialadenitis caused by ductal laceration. As surgical treatment sialodochoplasty was selected. The case and relevant considerations are discussed.

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.01a
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• pp.27-29
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• 2015

최근 IT기술의 발달로 인하여 다양한 분야에서 IT기술을 활용한 융합기술의 시도가 많아지고 있다. 특히 인터넷의 발달과 전자책(e-Book) 시장규모가 커짐에 따라 도서에 대한 정보가 많아지고 있으며, 이러한 정보를 분석하여 활용하는 서비스 시스템에 대한 관심이 높아지고 있다. 하지만 현재 서비스되고 있는 대부분의 온라인 서점에서는 도서의 기본 서지정보와 같이 도서 본문 내용과는 무관한 출판사나 서점에서 도서를 관리하기 위한 정보만을 제공하고 있으며, 도서에 대한 다양한 정보를 활용한 키워드 추출 및 장르 분류를 통한 검색의 효율성 제공이 미흡한 현실이다. 본 논문에서는 도서의 본문 텍스트 정보를 마이닝 처리하여 도서 페이지의 흐름에 따라 포함되어있는 장르를 분류하고 이에 대한 결과를 사용자에게 친화적인 시각화 기법으로 제공되는 시스템을 설계하고 구축하였다. 제안한 서비스 시스템은 의미 분석을 기반으로 도서 정보의 구체적, 실제적, 직관적 정보를 제공하여 도서 추천 서비스에 활용될 것이다.

• Journal of Environmental Health Sciences
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• v.37 no.5
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• pp.342-347
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• 2011

Healthy worker effect (HWE) refers to the consistent tendency for actively employed individuals to have a more favorable mortality experience than the population at large. Although HWE has been well known since the 1970s, only a few studies in occupational epidemiology have attempted to fully define and evaluate HWE. HWE can be separated into effects on the initial hiring into the workforce (healthy worker hire effect) and those on continuing employment (healthy worker survival effect). In this review, we summarize the methods for minimizingor adjusting for the healthy worker effect available in occupational epidemiology. It is noteworthy that healthy worker survival effect appears complicated, considering that employment status plays simultaneous roles as a counfounding variable and intermediate variable, whereas healthy worker hire effect may be adjusted by incorporating health status at baseline into the statistical model. In addition, two retrospective cohort studies for workers in the semiconductor industry and Vietnam veterans in Korea, respectively, were introduced, and their results were explained in terms of healthy worker effect.

• Journal of Environmental Health Sciences
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• v.37 no.2
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• pp.81-93
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• 2011

Although pesticides have increased crop production and controlled disease, they have produced a number of adverse health effects. Pesticides have potential human toxicity and a variety of groups, such as farmers or industrial workers, as well as the general population, are exposed to pesticides. The purpose of this article, therefore, is to provide an overview of pesticide exposure and health through a literature review, focusing on exposure assessment, acute poisoning, chronic health effects, and future research needs. The exposure types and levels of pesticides vary by study subjects and need to be assessed by integrating several methods focused on the epidemiological purpose. Acute pesticide poisoning is a major public health problem in the world. Paraquat is the main causative pesticide for acute poisoning in Korea and should be banned in order to save several thousands of lives every year. Occupational pesticide exposure also causes numerous chronic diseases among farmers and industrial workers, including cancers, respiratory diseases, depression, retinal degeneration, diabetes, and abnormal menstrual cycle. However, controversy exists regarding the long-term effects of low-dose environmental pesticide exposure. The area of pesticide study is relatively new with broad study populations and it has received little academic and policy attention, particularly in Korea. More detailed studies investigating the risk of pesticide-related health effects and intervention efforts to reduce the problems are needed in Korea.

• Journal of Chest Surgery
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• v.35 no.7
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• pp.560-563
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• 2002

Unilateral diaphragmatic paralysis due to a phrenic nerve injury is not rare after cardiothoracic surgery and may range from an asymptomatic radiographic abnormality to severe pulmonary dysfunction and even mortality in patients with reduced lung function. The most effective treatment for symptomatic unilateral diaphragmatic paralysis has been known to be a plication of the paralyzed hemidiaphragm. A 38 year-old male patient with asthma received a phrenic nerve reconstruction with a sural nerve for right phrenic nerve injury during resection of the anterior mediastinal tumor. Ten months later, chest PA showed good result and we report this case with literature.

• Imaging Science in Dentistry
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• v.38 no.2
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• pp.117-120
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• 2008

The odontogenic keratocyst (OKC) is a developmental odontogenic cyst typically occurring in the jaws. Since the first description of OKC was published in 1956, the lesion has been of particular interest because of its specific histopathologic features, high recurrence rate, and aggressive behavior. Recurrences most commonly arise within bone at the site of the original cyst. However, as lining cells may find their way into surrounding tissues either from implantation during surgery or from cortical perforation recurrences may arise at a distance from the original cyst. Here, we report a rare case of recurrent OKC which was first developed in mandible and recurred within the masticatory space.