• 건강소식
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• v.32 no.3 s.352
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• pp.34-36
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• 2008

어린 아이들에게 성교육이 필요하다고 이야기 한다면, 당신은 어떻게 받아들이겠는가. '아이의 성교육'이란 말 자체를 거론하기 전에 부모의 성의식부터 올바로 가져야 할는지도 모르겠다. 그만큼 성은 금기라는 울타리 안에서 마땅히 알아야 할 것조차 쉬쉬함으로써 여러 부작용을 낳았고 그것이 대물림되고 있다는 게 현대 성의식을 진단하는 전문가들의 견해다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.1
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• pp.66-71
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• 2004

Airborne contaminant particles are intruded into optical disk drive(ODD) due to the flow caused by disk rotation and can be adhered to objective lens, which causes read/write errors. Such a phenomenon can be a serious problem for high-density storage devices. The purpose of this paper is to understand the effect of particle contamination of objective lens in a CD-ROM drive on laser diode power and photo diode RF signal. The measurements of laser power and readout RF signal were carried out by using a laser power meter and a time interval analyzer, respectively. The parameters for estimating a readout-signal' distortion were its jitter and amplitude. Alumina(Al$_2$O$_3$) particles were used as test dust particles. The results show that the failure for data access happened as the degree of lens contamination was greater than 20％.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.11
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• pp.92-98
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• 2009

The scanning electron microscope (SEM) contains an electron optical system in which electrons are emitted and moved to form a focused beam, and generates secondary electrons from the specimen surfaces, eventually making an image. The electron optical system usually contains two condenser lenses and an objective lens. The condenser lenses generate a magnetic field that forces the electron beams to form crossovers at desired locations. The objective lens then focuses the electron beams on the specimen. The present study covers the design and analysis of an objective lens for a thermionic SEM. A finite element (FE) analysis for the objective lens is performed to analyze its magnetic characteristics for various lens designs. Relevant beam trajectories are also investigated by tracing the ray path of the electron beams under the magnetic fields inside the objective lens.

• 월간 기계설비
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• s.223
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• pp.42-46
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• 2009

최근 건설경기 침체에 따라 하도급 대금을 현금으로 지급하지 않고 불법 장기어음이나 미분양 아파트로 대물변제 등의 불법 하도급대금 지급행위를 근절하기 위해 국토해양부가 지난 1월 28일부터 '하도급대금 지급확인제도' 시행에 들어갔다. 하도급대금 지급확인제도는 원도급자가 하도급자에게 지급한 공사대금 내역과 하도급자가 수령한 하도급 대금을 발주자가 직접 비교 확인하여 하도급 대금의 적정지급 여부를 점검토록 한 것으로, 국토부 산하 지방청(국토관리 해양항만 항공)과 공사 공단에 전담부서를 지정하여 수시로 지급실태를 점검하고, 5개 국토관리청이 관할 구역 내에 공공발주 공사에 대하여 하도급대금 시급 실태를 총괄 관리하는 제도이다. 이 제도의 시행으로 공공공사에서는 불법 하도급대금 지급행위를 원천 차단 하여 불법 부당한 대금지급 관행이 근절될 것으로 기대된다. 이같은 제도를 시행하게 된 것은 그동안 대한설비건설협회(회장 강석대)가 불법 하도급대금 지급 근절을 위해 끊임없이 건의한 결과이다. 협회는 그동안 2차례에 걸친 국토부 차관과의 간담회를 비롯하여, 한나당 및 국토부 등 관련기관에 수차례에 걸쳐 건의했으며, 특히 연말에 이명박 대통령께 직법 건의하는 등 불법 하도급대금의 근절을 위해 많은 노력을 기울였다. 협회의 이러한 건의에 대해 국토부가 일정 부분을 수용함으로써 이 제도가 시행된 것이다.

• The Korean Journal of Applied Statistics
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• v.26 no.2
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• pp.237-252
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• 2013

An estimation model for premiums and components is essential to determine reasonable insurance premiums. In this study, we introduce diverse models for the estimation of property damage premiums(premium, depth and frequency) that include a regression model using a dummy variable, additive independent variable model, autoregressive error model, seasonal ARIMA model and intervention model. In addition, the actual property damage premium data was used to estimate the premium, depth and frequency for each model. The estimation results of the models are comparatively examined by comparing the RMSE(Root Mean Squared Errors) of estimates and actual data. Based on real data analysis, we found that the autoregressive error model showed the best performance.

• Korean Journal of Optics and Photonics
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• v.3 no.3
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• pp.143-147
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• 1992

1)iscussed in this paper are the effects of phase modulation on the line spread functions (LSF) and MTFs of ;I binocular objective system. The binocular objective lens is made in Korea. It has rotationally symmetric aberrations. The LSFs and MTFs are measured experimentally. The phase modulation is carried out by applying phase retardation $\pi$ on the aperture. The area where the phase is not retarded presents a double annular type. The OTF curves of phase modulated aperture are compared with that of unmodulated aperture. The comparison shows that there is the aberration compensation effect in aberration loaded system. Therefore the performance of many optical system can be improved without any loss of light energy by properly modulating the phase on the aperture.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.4
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• pp.509-517
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• 2013

Purpose: The purpose of this study is developing the 2.6 ${\times}$ optical scope with a Abbe-K$\ddot{o}$nig prism. Methods: First, considering the size of the effective aperture and the focal length of the objective lens, we designed an Abbe-K$\ddot{o}$nig prism. Next, we calculated the optical and geometric distances of Abbe-K$\ddot{o}$nig prism designed in this way. After allocating the focal length of the objective lens and the eyepiece lens so as to satisfy the magnification and optical effective distance of the entire system by using this calculation result, we completed the entire system by optimizing this optical system. Results: We were able to complete the optical scope of about 2.6 ${\times}$ magnification by designing an objective lens with a focal length of 63.13 mm which was composed of two pieces, an eyepiece with a focal length of 24.3 mm which was composed of four pieces, and an Abbe-K$\ddot{o}$nig prism with a face length 11.5 mm. Conclusions: We designed and fabricated an optical scope with 2.6 ${\times}$ magnification employing an Abbe-K$\ddot{o}$nig prism. Then, this system became the compacted optical system with a barrel diameter of 31 mm, characterized by an effective aperture of 12.0 mm and an effective optical barrel length of 103 mm and a resolution of 200 cycles/rad at 50% MTF criterion within the half viewing field angle of $6.42^{\circ}$.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.15-21
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• 2007

This paper proposes an improved methodology for estimating traffic accident cost savings in the transport appraisal. Four major problems from the existing framework are identified and their alternatives are suggested. First, casualties in the established approach are classified by just two types of 'killed' and 'injured'. This study supplies the indices of fatality further details. Namely, road victims are regrouped by 'killed', 'seriously injured', 'slightly injured', and 'accident reports'. Those of railways are similarly sorted by 'killed', 'seriously injured', and 'slightly injured'. Second, damage only accidents are not satisfactorily considered in the current arrangement. The accidents should be considered as one of the accident types and the social cost of them should also be evaluated. Third, the unit cost of accidents is given by the total value. The unit cost is consisted of several elements and each loss would be useful for a policy frame. This study breaks down the total figure into four pieces of costs, namely production loss, medical treatment, property loss, and administrative costs. Finally, there is inconsistency in the audit between roads and railways. Road accidents are analyzed by road types. On the other hand, patronage or others is the classification rule of rail accident costs. This paper suggests a way that the accident costs of two modes can be coherently estimated based on the level of services by each mode. The result of this study is expected to help frame more cautious social overhead capital investment policies.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.134-135
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• 2003

인체안의 단색수차는 시력의 한계를 규정하고 또한 안광학 기기의 설계에 있어서 중요한 요소이기 때문에 오래 전부터 많은 관심을 갖게 되었다. 또한 단색수차를 정밀하게 측정함으로써 가장 이상적인 시력 교정 방법을 찾을 수 있다. 본 연구에서는 먼저 그림 1과 같은 Shack-Hartmann (SH) 파면분석기를 구성하였다. 이 파면분석기는 대물렌즈, 결상렌즈, 미소렌즈배열(microlens array, MLA), 그리고 이미지 센서(CCD)로 구성되어 있다. (중략)

• Proceedings of the Optical Society of Korea Conference
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• 2006.02a
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• pp.113-114
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• 2006