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Intercomparison of Daegwallyeong Cloud Physics Observation System (CPOS) Products and the Visibility Calculation by the FSSP Size Distribution during 2006-2008 (대관령 구름물리관측시스템 산출물 평가 및 FSSP를 이용한 시정환산 시험연구)

  • Yang, Ha-Young;Jeong, Jin-Yim;Chang, Ki-Ho;Cha, Joo-Wan;Jung, Jae-Won;Kim, Yoo-Chul;Lee, Myoung-Joo;Bae, Jin-Young;Kang, Sun-Young;Kim, Kum-Lan;Choi, Young-Jean;Choi, Chee-Young
    • Korean Journal of Remote Sensing
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    • v.26 no.2
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    • pp.65-73
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    • 2010
  • To observe and analyze the characteristics of cloud and precipitation properties, the Cloud physics Observation System (CPOS) has been operated from December 2003 at Daegwallyeong ($37.4^{\circ}N$, $128.4^{\circ}E$, 842 m) in the Taebaek Mountains. The major instruments of CPOS are follows: Forward Scattering Spectrometer Probe (FSSP), Optical Particle Counter (OPC), Visibility Sensor (VS), PARSIVEL disdrometer, Microwave Radiometer (MWR), and Micro Rain Radar (MRR). The former four instruments (FSSP, OPC, visibility sensor, and PARSIVEL) are for the observation and analysis of characteristics of the ground cloud (fog) and precipitation, and the others are for the vertical cloud characteristics (http://weamod.metri.re.kr) in real time. For verification of CPOS products, the comparison between the instrumental products has been conducted: the qualitative size distributions of FSSP and OPC during the hygroscopic seeding experiments, the precipitable water vapors of MWR and radiosonde, and the rainfall rates of the PARSIVEL(or MRR) and rain gauge. Most of comparisons show a good agreement with the correlation coefficient more than 0.7. These reliable CPOS products will be useful for the cloud-related studies such as the cloud-aerosol indirect effect or cloud seeding. The visibility value is derived from the droplet size distribution of FSSP. The derived FSSP visibility shows the constant overestimation by 1.7 to 1.9 times compared with the values of two visibility sensors (SVS (Sentry Visibility Sensor) and PWD22 (Present Weather Detect 22)). We believe this bias is come from the limitation of the droplet size range ($2{\sim}47\;{\mu}m$) measured by FSSP. Further studies are needed after introducing new instruments with other ranges.

Establishment Method of the Regulatory Framework for Communications Reflecting the Ecosystem Elements (생태계 요소를 반영한 방송통신 규제체계의 정립 방안)

  • Hong, Dae-Sik;Choe, Dong-Uk
    • Journal of Legislation Research
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    • no.41
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    • pp.401-434
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    • 2011
  • The discussion on the adoption of the horizontal regulatory framework is underway to overcome the problems regarding the vertical regulatory framework resulting from a convergence of broadcasting and telecommunications services. Recently, however, the horizontal regulatory framework shows its limitation to regulate the ecosystem established mainly by Google and Apple. The existing horizontal regulatory framework does not fully reflect the characteristics of the two-sided market and the change in the competition structure in the broadcasting and telecommunications sector. What is important to note is that if the existing horizontal regulatory framework is simply applied to the ecosystem, a regulatory imbalance can be caused among ecosystems. The existing horizontal regulatory framework, which is subject to a value chain structure, categorizes business entities into either contents layer or transmission layer and applies the same regulation to all business entities in the same category. However, in the ecosystem, a keystone-player can be categorized into different layers depending on its strategy. Therefore, if the existing horizontal regulatory framework is applied as it is, the regulatory imbalance between keystone-players located in less regulated areas and keystone-players located in more regulated areas occurs resulting in a distortion of competition. There are two possible ways to establish a new regulatory framework to prevent the distortion of competition likely to be caused by the adoption of a horizontal regulatory system. First, a new ecosystem regulatory framework different from the existing one can be established. Second, the horizontal regulatory framework can be modified to reflect the ecosystem elements. The first approach is hard to adopt given the current situation as the approach requires the analysis of all broadcasting and telecommunications ecosystems including mobile and wired services; currently research and study on the competition conditions in the ecosystems is not enough. Therefore, this paper supports the second approach proposing a modified horizontal regulatory framework through the improvement of institutions and remedies suitable for accommodating the ecosystem elements. This paper intends to propose a way to regulate broadcasting and telecommunications ecosystems taking into consideration the ecosystem elements on top of the Telecommunications Business Act, Broadcasting Act, IPTV Act, the competition condition evaluation system of the Basic Act on Broadcasting and Telecommunications Development, and regulation on common carriers under the Telecommunications Business Act.

A Study on the Justification for Disciplinary by the reason for Whistle-blowing (근로자의 내부고발을 이유로 한 징계의 정당성)

  • Choi, Hong-Ki
    • Journal of Legislation Research
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    • no.44
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    • pp.611-653
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    • 2013
  • An whistle-blowing is recognition of acts of misconduct or corruption by individuals(laborers) or party which belongs to a certain organization and it refers to the act of informing to the senior organization or to the outside public agency to avoid jeopardies that could be potentially lead against benefit of the public. These whistle-blowings can be a Ansatz that improve corporation's transparency and accountability by prevention of enterprise's misconduct as well, it has been recognized as an important role for the establishment of corporate ethics, moreover, social justice. What to be treated primarily as labor law problem is arousing some controversies of the possibility that the public announcement could be whether a disciplinary punishment or not because it brings some mischievous effects for the honor and the reputation to the company which conducted the illegal actions and the action of the contrary to the social value. And futhermore, recently, the matter of compensational responsibility according to the arrangement conversion, bullying followed by the informant has been brought up. The fundamental standpoint of precedent related with the judgement of justification for the punishment as reason of the whistle-blowing ought to do the sincere duty for the labor contract which is the employees are supposed to consider the employer's profits. For that reason, if the emploee release the inside fact to the public and give any damages to employer's secret or confidence or honor, it will be a causing reasong of the disciplinary punishment, but in specific cases, the relevant and level of punishment limitation can be judged by the contents of public announcement and the truth, the purpose of the acts and details and the way of announcement. Precisely, on the assumption that there are necessity of the characteristic profit or the freedom of expression for the informant, with overall consideration whether or the basis part of the informant is true or there is a fair reason which make the informant believe is true or the purpose of informant has the public profit or the contents of the whistle-blowing are important for relevant organization or the means and the way was suitable, if the whistle-blowing are approved to be resonable, the organization are not permitted the reprimand or dismiss Futhermore, to find the solution for the issues of the disciplinary punishment and the treatment of all sorts of disadvantages, for the reason of whistle-blowing, since the protection law for public declarer which was enacted in last 2011 have the position as the general law, the purport of the equal law has to be considered sytematically and also the judicial precedent which is related to the justification of whistle-blowing are needed to be considered as well.

Efficacy and Safety of Topical Application of Epidermal Growth Factor (EGF) for Korean Acne Patient (한국인 여드름 환자에서 표피성장인자가 함유된 외용제의 피부 적용에 대한 유효성 및 안전성 평가)

  • Suh, Joon Hyuk;Hyun, Moo Yeol;Jang, Seong Eum;Choi, Sun Young;Kim, Myeung Nam;Kim, Beom Joon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.2
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    • pp.111-118
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    • 2016
  • Acne vulgaris is a chronic inflammatory condition characterized by comedo, papule, cyst, nodule and postinflammatory hyperpigmentation. Meanwhile, it is also induced by adverse event of drugs. Among them, acneiform folliculitis is a side effect of epidermal growth factor receptor (EGFR) inhibitor, which is an anticancer agent, and its incidence may occur in upward of 75 ~ 100% of cases. The main method of acne vulgaris treatment is oral antibiotics, retinoids, topical medication and so on. However, it is limitation that teratogenicity caused by retinoids and antibiotic resistance increased by using antibiotics. In this study, we aimed to evaluate the clinical efficacy and safety of topical recombinant human (rh) EGF in treating facial acne vulgaris. Twenty three Koreans (age: 10 ~ 29 years) with mild to moderate acne vulgar participated in the study and applied topical rhEGF cream (trouble control EGF) with 3 products (trouble control clarifying cleansing foam, trouble control all-clear filling toner, redroll calming moisture) on their face twice daily for four weeks. Several assessment methods were applied: Acne lesion counts score by investigator's global assessment, efficacy and satisfaction score by subjects. Skin sebum output level, hydration level and redness level were also measured at each visit. At the final visit, skin sebum level, transepidermal water loss, skin redness statistically decreased and acne lesions (comedone, papule) were statistically reduced. No severe side effects were observed during the study. In conclusion, topical rhEGF seems to be an effective and safe adjuvant treatment option for mild acne vulgaris.

Effects of Horticultural Therapy on the Improvement of the Self-Esteem and Sociality of Mentally Retarded Persons (원예치료프로그램의 적용이 정신지체장애인의 자기주장 및 사회성 향상에 미치는 영향)

  • 박민희;차영주;유영원;부희옥;이숙영
    • Korean Journal of Plant Resources
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    • v.17 no.3
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    • pp.339-351
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    • 2004
  • This study was conducted to evaluate the effect of phased horticultural therapy(HT) program on the experience of psychologic therapy and the development of job and social integration in the mentally handicapped persons. In this study, the mentally handicapped persons participated in HT program were chosen in disabled person's welfare institute of Jeonnam. HT program was performed twice a week with 1 hour activity for 4 months. As a results, the mentally handicapped persons participated in HT program showed high interest of horticulture and improvement of self-respect and the high satisfactory degree of HT program. Therefore, the mentally handicapped persons were showed the experience of both physical and mental therapy, improvement of self-esteem scale and sociality in HT program. Also, the application of HT program with continuously interest will be showed high improvement of physical, psychological and sentimental. In the course of this HT program progress, horticultural therapist and social welfare officer were showed the limitation of role. Therefore the leaders of group for successful HT program be required the comprehensive plan of more efficient HT program and induced technique of continuously up-phased improvements in HT program progress.

Derivation of Green Coverage Ratio Based on Deep Learning Using MAV and UAV Aerial Images (유·무인 항공영상을 이용한 심층학습 기반 녹피율 산정)

  • Han, Seungyeon;Lee, Impyeong
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1757-1766
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    • 2021
  • The green coverage ratio is the ratio of the land area to green coverage area, and it is used as a practical urban greening index. The green coverage ratio is calculated based on the land cover map, but low spatial resolution and inconsistent production cycle of land cover map make it difficult to calculate the correct green coverage area and analyze the precise green coverage. Therefore, this study proposes a new method to calculate green coverage area using aerial images and deep neural networks. Green coverage ratio can be quickly calculated using manned aerial images acquired by local governments, but precise analysis is difficult because components of image such as acquisition date, resolution, and sensors cannot be selected and modified. This limitation can be supplemented by using an unmanned aerial vehicle that can mount various sensors and acquire high-resolution images due to low-altitude flight. In this study, we proposed a method to calculate green coverage ratio from manned or unmanned aerial images, and experimentally verified the proposed method. Aerial images enable precise analysis by high resolution and relatively constant cycles, and deep learning can automatically detect green coverage area in aerial images. Local governments acquire manned aerial images for various purposes every year and we can utilize them to calculate green coverage ratio quickly. However, acquired manned aerial images may be difficult to accurately analyze because details such as acquisition date, resolution, and sensors cannot be selected. These limitations can be supplemented by using unmanned aerial vehicles that can mount various sensors and acquire high-resolution images due to low-altitude flight. Accordingly, the green coverage ratio was calculated from the two aerial images, and as a result, it could be calculated with high accuracy from all green types. However, the green coverage ratio calculated from manned aerial images had limitations in complex environments. The unmanned aerial images used to compensate for this were able to calculate a high accuracy of green coverage ratio even in complex environments, and more precise green area detection was possible through additional band images. In the future, it is expected that the rust rate can be calculated effectively by using the newly acquired unmanned aerial imagery supplementary to the existing manned aerial imagery.

Comparative Assessment of Linear Regression and Machine Learning for Analyzing the Spatial Distribution of Ground-level NO2 Concentrations: A Case Study for Seoul, Korea (서울 지역 지상 NO2 농도 공간 분포 분석을 위한 회귀 모델 및 기계학습 기법 비교)

  • Kang, Eunjin;Yoo, Cheolhee;Shin, Yeji;Cho, Dongjin;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1739-1756
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    • 2021
  • Atmospheric nitrogen dioxide (NO2) is mainly caused by anthropogenic emissions. It contributes to the formation of secondary pollutants and ozone through chemical reactions, and adversely affects human health. Although ground stations to monitor NO2 concentrations in real time are operated in Korea, they have a limitation that it is difficult to analyze the spatial distribution of NO2 concentrations, especially over the areas with no stations. Therefore, this study conducted a comparative experiment of spatial interpolation of NO2 concentrations based on two linear-regression methods(i.e., multi linear regression (MLR), and regression kriging (RK)), and two machine learning approaches (i.e., random forest (RF), and support vector regression (SVR)) for the year of 2020. Four approaches were compared using leave-one-out-cross validation (LOOCV). The daily LOOCV results showed that MLR, RK, and SVR produced the average daily index of agreement (IOA) of 0.57, which was higher than that of RF (0.50). The average daily normalized root mean square error of RK was 0.9483%, which was slightly lower than those of the other models. MLR, RK and SVR showed similar seasonal distribution patterns, and the dynamic range of the resultant NO2 concentrations from these three models was similar while that from RF was relatively small. The multivariate linear regression approaches are expected to be a promising method for spatial interpolation of ground-level NO2 concentrations and other parameters in urban areas.

Estimation of Ground-level PM10 and PM2.5 Concentrations Using Boosting-based Machine Learning from Satellite and Numerical Weather Prediction Data (부스팅 기반 기계학습기법을 이용한 지상 미세먼지 농도 산출)

  • Park, Seohui;Kim, Miae;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.321-335
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    • 2021
  • Particulate matter (PM10 and PM2.5 with a diameter less than 10 and 2.5 ㎛, respectively) can be absorbed by the human body and adversely affect human health. Although most of the PM monitoring are based on ground-based observations, they are limited to point-based measurement sites, which leads to uncertainty in PM estimation for regions without observation sites. It is possible to overcome their spatial limitation by using satellite data. In this study, we developed machine learning-based retrieval algorithm for ground-level PM10 and PM2.5 concentrations using aerosol parameters from Geostationary Ocean Color Imager (GOCI) satellite and various meteorological parameters from a numerical weather prediction model during January to December of 2019. Gradient Boosted Regression Trees (GBRT) and Light Gradient Boosting Machine (LightGBM) were used to estimate PM concentrations. The model performances were examined for two types of feature sets-all input parameters (Feature set 1) and a subset of input parameters without meteorological and land-cover parameters (Feature set 2). Both models showed higher accuracy (about 10 % higher in R2) by using the Feature set 1 than the Feature set 2. The GBRT model using Feature set 1 was chosen as the final model for further analysis(PM10: R2 = 0.82, nRMSE = 34.9 %, PM2.5: R2 = 0.75, nRMSE = 35.6 %). The spatial distribution of the seasonal and annual-averaged PM concentrations was similar with in-situ observations, except for the northeastern part of China with bright surface reflectance. Their spatial distribution and seasonal changes were well matched with in-situ measurements.

Thought Experiments: on the Working Imagination and its Limitation (사고실험 - 상상의 작용과 한도에 대해)

  • Hwang, Hee-sook
    • Journal of Korean Philosophical Society
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    • v.146
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    • pp.307-328
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    • 2018
  • The use of thought experiments has a long history in many disciplines including science. In the field of philosophy, thought experiments have frequently appeared in the pre-existing literature on the contemporary Analytic Philosophy. A thought experiment refers to a synthetic environment where the designer of the experiment-with his or her intuition and imagination-tests common-sense knowledge. It can be understood as a conceptual tool for testing the validity of the common understanding of an issue or a phenomenon. However, we are not certain about the usefulness or efficacy of a thought experiment in knowledge production. The design of a thought experiment is meant to lure readers into believing as intended by the experiment itself. Thus, regardless of the purpose of a thought experiment, many readers who encounter the experiment could feel deceived. In this paper, to analyze the logic of thought experiments and to seek the source of uneasiness the readers and critics may feel about thought experiments, I draw lessons from three renowned thought-experiments: Thomson's 'ailing violinist', Putnam's 'brain in a vat', and Searle's 'Chinese room'. Imaginative thought experiments are usually constructed around a gap between the reality and the knowledge/information at hand. From the three experiments, several lessons can be learned. First, the evidence of the existence of a gap provided via thought experiments can serve as arguments for counterfactual situations. At the same time, the credibility and efficacy of the thought experiments can be damaged as soon as the thought-experiments are carried out with inappropriate and/or murky directions regarding the procedures of the experiment or the background of the study. According to D. R. Hofstadter and D. C. Dennett(1981), the 'knob setting' in a thought experiment can be altered in the middle of a simulation of the experimental condition, and then the implications of the thought experiment change altogether, indicating that an entirely different conclusion can be deduced from thought experiment. Lastly, some pre-suppositions and bias of the experiment designers play a considerable role in the validity and the chances of success of a thought experiment; thus, it is recommended that the experiment-designers refrain from exercising too much of their imagination in order to avoid contaminating the design of the experiment and/or wrongly accepting preconceived/misguided conclusions.

The Separation of Church and State and Religious Policy in Modern Korea (한국의 정교분리와 종교정책)

  • Yoon, Seung Yong
    • The Critical Review of Religion and Culture
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    • no.25
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    • pp.195-241
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    • 2014
  • When the objective of a modern state focuses on securing basic human right of an individual and realizing public good in a state community, the direction of policy on religion of a state can not deviate far away from such objective. Meanwhile, the policy on religion of modern states today mostly takes the church and state separation principle as its basis. The states secure religious freedom and enforce the separation of church and state by differentiating religion and the mundane world and establishing the relation between the two. This study examined the church and state separation principle, which is an important system device of recent age nation-states, and explored the possibility of more active policy on religion. First, the relationship among religion, state and politics was examined from more structural and functional viewpoint. Next, how the separation of church and state principle has become recent age political principle and what was the settlement process of church and state separation in other countries are summarized. At last, the actual situation of church and state separation in Korea, the structural limitation of it and the direction of policy on religion are examined. The application experience of church and state separation principle is quite short in Korean society. In addition, when there is a religious issue, there is the trend of evading the issue unconditionally or responding to it passively. However, the religious culture in Korean society is one of the biggest cultural resources and social assets. Since it has big potential as driving force for the advance of state, it is regretful to leave religion alone as it is. Therefore, this study explored the original limitations of church and state separation principle which are limiting the religious policy of of state and searched for a theoretical basis for the utilization of resources in religious culture as driving force of state by overcoming the limitations. This study examined the situation in Korea by paying attention to how differently the church and state separation principle is being applied in other states, The separation of church and state, which is the basis of policy on religion in Korea, belongs to 'similar separation type' like in Japan; therefore, there is a trend of doctrinaire interpretation or arbitrary interpretation. This study suggests that it is required to overcome this limping state and settle down the church and state separation principle, which fits to Korean society, as a social and cultural practice. It is also suggested that more active policy on religion would be enforced by wider interpretation of church and state separation.