• 노동경제논집
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• 제27권3호
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• pp.1-23
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• 2004

"한국노동패널"을 이용하여 조기은퇴 행위와 지연은퇴 행위가 은퇴 전 후 소비에 미치는 영향을 2단계 전환회귀분석방법으로 분석하였다. 추정 과정에서 본 논문에서는 조기은퇴 결정이 은퇴 전 후 소비에 미치는 영향을 크게 두 가지로 구분하였다. 첫 번째는 조기은퇴 결정이 존재하는 경우와 존재하지 않는 경우를 비교하는 것으로서 추정결과 선택편의(selection bias)가 존재하는지를 통해 살펴보았다. 두 번째는 조기은퇴 결정 후 조기은퇴자의 소비를 지연은퇴자의 소비와 비교하는 것으로서, 소비의 소득탄력성을 비교하여 살펴보았다. 추정 결과 조기은퇴를 결정했을 경우 조기은퇴 결정이 존재하지 않는 경우와 비교했을 때 은퇴 전 소비가 감소하는 것으로 나타났다. 그리고 조기은퇴자와 지연은퇴자의 소비의 소득탄력성을 비교해 본 결과 소득이 증가하였을 때 조기은퇴자의 소비 증가폭이 지연은퇴자보다 작았다. 이상의 결과는 조기은퇴 결정 이후 상대적으로 길어진 은퇴 기간이 은퇴 전 소비에 영향을 미치고 있음을 보여주는 것이다.

• 한국방재학회 논문집
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• 제7권4호
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• pp.19-29
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• 2007

본 연구에서는 레이더 강우의 지상보정(ground-truth)을 위해 사용가능한 기상청(KMA), AWS 및 건설교통부(MOCT) 강우 자료를 다양한 지상보정 설계에 적용하여 비교 평가하였다. 본 연구에서는 동일 기간의 KMA, MOCT, AWS의 우량계 자료와 관악산 레이더 강우 자료를 이용하였으며, 각각 두 관측방법 사이의 차이(오차)를 편의(bias)의 유무 및 크기의 관점에서 평가하였다. 추가로 호우 사상의 특성에 따른 차이도 함께 검토하였다. 그 적용 결과 지상우량계 자료별 편의의 차이는 확연하게 부각되지는 않았으나, 통계 특성치에서는 어느 정도의 차이가 존재함을 확인하였다. 전체적으로 보면 MOCT 우량계 자료를 이용하는 경우가 다른 강우 자료를 이용하는 경우에 비해 편의의 규모가 가장 작은 것으로 파악되었다. 호우 사상별로는 강우의 공간적 간헐성이 가장 큰 장마 기간의 경우가 태풍이나 대류성 강우에 비해 설계편의가 작게 나타나는 것으로 확인되었다.

• 한국항공우주학회지
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• 제31권6호
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• pp.52-60
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• 2003

GPS(Global Positioning System)를 이용한 항공항법은 이용성과 무결성의 만족을 절대적으로 요구하고 있다. GPS의 무결성에 대한 연구로서 GPS수신기 내부 자체에서 무결성을 모니터링하는 다양한 RAIM(Receiver Autonomous Integrity Monitoring)기법이 연구되어 왔으며 이들 중에서 패러티 공간을 이용한 고장진단기법은 패러티 백터의 크기와 방향성을 이용할 수 있는 편리성을 갖고 있어 비교적 많은 연구가 진행되어 왔다. 한편, 지금까지의 RAIM 기법들은 대부분 단일고장을 가정하며, 실제 적용시 발생할 수 있는 다중고장의 경우 오차요인들의 상호간섭으로 정확한 식별이 어렵다는 단점을 갖고 있다. 본 논문에서는 확장된 패러티 공간에서 고장진단을 다룸으로써 2개의 고장식별에의 적용이 가능함을 보였다.

• Geomechanics and Engineering
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• 제16권1호
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• pp.21-34
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• 2018

Discontinuities considerably affect the mechanical and hydraulic properties of rock mass. These properties of the rock mass are influenced by the geometry of the discontinuities to a great extent. This paper aims to render an account of the geometrical parameters of several discontinuity sets related to the surrounding rock mass of Rudbar Lorestan Pumped Storage Power Plant powerhouse cavern making use of the linear and areal (circular and rectangular) sampling methods. Taking into consideration quite a large quantity of scanline and the window samplings used in this research, it was realized that the areal sampling methods are more time consuming and cost-effective than the linear methods. Having corrected the biases of the geometrical properties of the discontinuities, density (areal and volumetric) as well as the linear, areal and volumetric intensity accompanied by the other properties related to four sets of discontinuities were computed. There is an acceptable difference among the mean trace lengths measured using two linear and areal methods for the two joint sets. A 3D discrete fracture network generation code (3DFAM) has been developed to model the fracture network based on the mapped data. The code has been validated on the basis of numerous geometrical characteristics computed by use of the linear, areal sampling methods and volumetric method. Results of the linear sampling method have significant variations. So, the areal and volumetric methods are more efficient than the linear method and they are more appropriate for validation of 3D DFN (Discrete Fracture Network) codes.

• 여성건강간호학회지
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• 제5권3호
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• pp.265-276
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• 1999

Female nurses in Korea have historically experienced discrimination on the basis of their gender as part of the traditional society views on woman and as a result of the male dominated hospital environments. This discrimination may interfere with the ability of female nurses to promote the health of their patients. To better understand this bias, we collected and analyzed 16 cases of alleged sexual discrimination reported by female nurses with more than 5 years work experience. The cases were classified into 10 subjects and further into 4 categories: personnel administration, daily working environment, female gender bias, and health care delivery. There were 7 cases (11.3%) of unjust personnel changes consisting of demotion(1), termination(4), and reallocation of position(3). Twenty three (37.1%) of cases related to problems in the daily workplace including biases in communication between female nurses and male physicians(12), daily work(8), and responsibility for adverse outcomes(3). We noted 17 cases (27.4%) of female gender bias as reported by female nurses(7), female physicians(7), and female patients(3). Lastly, there were 15 (24.3%) cases of problems with health care delivery due to sexual discrimination, including enrollment in the health care system(4),and decisions regarding medical care(4). These results suggest that sexual discrimination towards women is pervasive in the Korea hospitals, not only towards female nurses but also towards female physicians and patients. More discriminatory practices in a timely fashion such that better nursing care can be provided to patients and their families.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1205-1210
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• 2014

Background: Previous studies on the association of oral contraceptives (OC) use and lung cancer generated inconsistent findings. The aim of this study was to confirm any definite correlation between OC use and lung cancer risk. Methods: Publications were reviewed and obtained through PubMed and EMBASE databases literature search up to November, 2013. Reference lists from retrieved articles were also reviewed. The language of publication was restricted to English. A meta-analysis was performed to evaluate the association by calculating pooled odds ratios (ORs) and 95% confidence intervals (CIs). Results: A total of 14 studies consisting of 9 case-control studies and 5 cohort studies were finally included in this meta-analysis. There was no significant association observed between OC use and lung cancer risk in the overall analysis (OR=0.91; 95% CI=0.81-1.03). There was a significant protective effect in Europe (OR=0.74; 95% CI=0.60-0.91) and a borderline significant protective effect with an adenocarcinoma histology (OR=0.90; 95% CI=0.80-1.01) in subgroup analyses. No association was observed for methodological quality of study, study design, smoking status and case number of study. Conclusion: This meta-analysis suggests that OC use is not likely to be associated with the risk of lung cancer at all. While a significant protective effect of OC use on lung cancer was observed in Europe, interpretation should be cautious because of the potential biases of low-quality studies. At the same time, more attention should be paid to the possible association of OC use with adenocarcinoma of lung. Our findings require further research, with well-conducted and large-scale epidemiological studies to confirm effects of OC use on lung cancer.

• 자원ㆍ환경경제연구
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• 제16권4호
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• pp.873-900
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• 2007

비시장재의 가치를 추정하는 많은 연구들은 비시장재에 대한 선호가 모든 경제주체에 있어서 동질적이라고 가정한다. 그러나 현실적으로 비시장재에 대한 선호가 경제주체마다 다를 수 있기 때문에 경제주체간 선호의 이질성을 가정하는 것이 합리적이며 가치추정의 편의를 감소시키게 될 것이다. 본 연구는 방사성 오염 물질인 라돈 가스 농도의 저감에 대한 선호와 도로교통 및 원자력발전의 안전에 대한 선호가 각각 가계들 사이에 이질적일 것인지, 그리고 가계들의 선호가 동질적임을 가정하는 경우에 비해 모형 및 비시장재 가치 추정에 어떠한 영향을 미치는지 분석하였다. 속성가치선택법(choice experiments)과 중첩로짓(mixed logit) 모형을 이용한 결과, 이질적 선호를 허용하는 것이 이를 배제하는 것보다 설명력 있는 모형을 가져다 주었다. 그리고 라돈 농도 저감 및 도로교통 안전 각각에 대하여 이질적 선호가 가계들 사이에 뚜렷이 존재하는 것으로 나타났다. 그러나 원자력발전 안전에 대한 선호의 이질성은 뚜렷이 존재하지 않았다. 이질적 선호를 배제하는 경우와 비교할 때 이를 허용하는 경우의 지불의사액은 라돈 농도 저감의 경우에 평균 2.44배 증가하였으며, 도로교통 안전의 경우에는 1.74배 증가하였다.

• 한국대기환경학회지
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• 제29권2호
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• pp.186-198
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• 2013

The present work is an attempt to improve the performance of a regional air quality model by means of liking it with a global chemistry transport model. The global chemical transport model of GEOS-Chem is used to provide BC (Boundary Condition)s which reflect temporal and spatial variations at boundaries of regional chemical transport model of CMAQ over East Asia. First, GEOS-Chem outputs are evaluated by comparing predicted concentrations with observed monthly data of gas phase species and secondary inorganic aerosols from EANET (Acid Deposition Monitoring Network in East Asia) sites. The results show that predicted PM10 concentrations are in good agreement with the observations. This implies that GEOS-Chem outputs could be used to provide BCs to CMAQ. Simulated daily and monthly mean PM10 concentrations of CMAQ with the linkage of GEOS-Chem's BCs and constant BCs are then evaluated by comparing predicted concentrations with observations at API (Air Pollution Index) sites in China as well as EANET sites in Korea. CMAQ with the GEOS-Chem outputs improves model simulation in depicting observed PM10 concentrations comparing with those with constant BCs. It is also found that influence of aerosol species are largely dependent on the BCs over East Asia and Korea. Mean biases between simulated versus observed daily and monthly mean concentrations of PM10 with the GEOS-chem were improved by 1~8 ${\mu}g/m^3$ in China region, 3.26 ${\mu}g/m^3$ in Korea.

• 무역상무연구
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• 제16권
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• pp.331-359
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• 2001

Uniform Electronic Transactions Act (1999) Drafted by the National Conference of Commissioners on Uniform State Laws. The Act allows the use of electronic records and electronic signatures in any transaction, except transactions subject to the Uniform Commercial Code. The fundamental purpose of this act is to remove perceived barriers to electronic commerce. The Act's a procedural statute. It does not mandate either electronic signatures or records, but provides a means to effectuate transactions when they are used. The primary objective is to establish the legal equivalence of electronic records and signatures with paper writings and manually-signed signatures. With regard to the general scope of the Act, the Act's coverage is inherently limited by the definition of "transaction." The Act does not apply to all writings and signatures, but only to electronic records and signatures relating to a transaction, defined as those interactions between people relating to business, commercial and governmental affairs. The exclusion of specific Articles of the Uniform Commercial Code reflects the recognition that, particularly in the case of Articles 5, 8 and revised Article 9, electronic transactions were addressed in the specific contexts of those revision processes. In the context of Articles 2 and 2A the UETA provides the vehicle for assuring that such transactions may be accomplished and effected via an electronic medium. At such time as Articles 2 and 2A are revised the extent of coverage in those Articles(Acts) may make application of this Act as a gap-filling law desirable. Similar considerations apply to the recently promulgated Uniform Computer Information Transactions Act (UCITA). Another fundamental premise of the Act is that it be minimalist and procedural. The general efficacy of existing law, in an electronic context, so long as biases and barriers to the medium are removed, confirms this approach. The Act defers to existing substantive law. Specific areas of deference to other law in this Act include: i) the meaning and effect of "sign" under existing law, ii) the method and manner of displaying, transmitting and formatting information in section 8, iii) rules of attribution in section 9, and iv) the law of mistake in section 10.

• 대한원격탐사학회지
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• 제33권1호
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• pp.1-13
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• 2017

This study investigates the geometric and spatial image quality analysis of KOMPSAT-3A stereo pair. KOMPSAT-3A is, the latest satellite of KOMPSAT family, a Korean earth observation satellite operating in optical bands. A KOMPSAT-3A stereo pair was taken on 23 November, 2015 with 0.55 m ground sampling distance over Terrassa area of Spain. The convergence angle of KOMPSAT-3A stereo pair was estimated as $58.68^{\circ}$. The investigation was assessed through the evaluation of the geopositioning analysis, image quality estimation and the accuracy of automatic Digital Surface Model (DSM) generation and compared with those of KOMPSAT-3 stereo pair with the convergence angle of $44.80^{\circ}$ over the same area. First, geopositioning accuracy was tested with initial rational polynomial coefficients (RPCs) and after compensating the biases of the initial RPCs by manually collected ground control points. Then, regarding image quality, relative edge response was estimated for manually selected points visible from two stereo pairs. Both of the initial and bias-compensated positioning accuracy and the quality assessment result expressed that KOMPSAT-3A images showed higher performance than those of KOMPSAT-3 images. Finally, the accuracy of DSMs generated from KOMPSAT-3A and KOMPSAT-3 stereo pairs were examined with respect to the reference LiDAR-derived DSM. The various DSMs were generated over the whole coverage of individual stereo pairs with different grid spacing and over three types of terrain; flat, mountainous and urban area. Root mean square errors of DSM from KOMPSAT-3A pair were larger than those for KOMPSAT-3. This seems due to larger convergence angle of the KOMPSAT-3A stereo pair.