• Title/Summary/Keyword: Time adjustment

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A cognitive survey on the Diversification of class year from Junior Colleges by Changing Educational Environment-Focused on Health Sciences Departments (교육환경 변화에 따른 전문대학 수업 연한 다양화에 대한 인식조사 - 보건계열학과 중심으로)

  • Park, Cheolin;Park, Su-Jin;Kwon, Soon-Mu;Kim, Won-Gi;Chang, Ki-whan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.4
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    • pp.186-196
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    • 2018
  • Junior colleges are higher education institutions that have played a major role in the economic development of Korea by providing the necessary human resources for its industrial development. Recently, however, they have experienced difficulties due to the reduction in the number of students. Therefore, it is time for junior colleges as a representative higher vocational education institution to change their role in this rapidly changing environment, and adopt a survival strategy through mutual cooperation and competition. The purpose of this study was to analyze the current state of the national health universities, to investigate the policy changes adopted by colleges and universities, and to utilize the results as data. This study analyzed the current status of health science colleges nationwide and investigated the policy changes as well as the directions presented to the colleges, in order to use the results as the basic data to promote the diversification of the class periods and degree programs. This study surveyed 636 professors from health sciences departments and industry workers from May 1 to May 30, 2017. 70.7% of the respondents supported the transition of the existing three-year systems of the health science departments to four-year systems. The reason for this is that it is possible to strengthen the field practice and personality education of the students by having a sufficient number of class periods, and to provide them with an equal educational background. The most anticipated effect of the transition to a four-year system is to improve the social status of medical personnel and to improve the educational environment of the colleges/universities. Moreover, the universities, associations of medical personnel and Ministry of Education are expected to play a leading role in the transition to the four-year system. Based on the results of this study, it was concluded that a more systematic and advanced vocational education system for the training of professional healthcare workers is needed in the upcoming fourth Industrial Revolution era. Also, this transition is expected to actively foster the education of advanced health care workers thanks to the diversification of the degree programs through the adjustment of the class periods which can be completed by general university (4-year) graduates.

Patients Setup Verification Tool for RT (PSVTS) : DRR, Simulation, Portal and Digital images (방사선치료 시 환자자세 검증을 위한 분석용 도구 개발)

  • Lee Suk;Seong Jinsil;Kwon Soo I1;Chu Sung Sil;Lee Chang Geol;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.21 no.1
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    • pp.100-106
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    • 2003
  • Purpose : To develop a patients' setup verification tool (PSVT) to verify the alignment of the machine and the target isocenters, and the reproduclbility of patients' setup for three dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT). The utilization of this system is evaluated through phantom and patient case studies. Materials and methods : We developed and clinically tested a new method for patients' setup verification, using digitally reconstructed radiography (DRR), simulation, porial and digital images. The PSVT system was networked to a Pentium PC for the transmission of the acquired images to the PC for analysis. To verify the alignment of the machine and target isocenters, orthogonal pairs of simulation images were used as verification images. Errors in the isocenter alignment were measured by comparing the verification images with DRR of CT Images. Orthogonal films were taken of all the patients once a week. These verification films were compared with the DRR were used for the treatment setup. By performing this procedure every treatment, using humanoid phantom and patient cases, the errors of localization can be analyzed, with adjustments made from the translation. The reproducibility of the patients' setup was verified using portal and digital images. Results : The PSVT system was developed to verify the alignment of the machine and the target isocenters, and the reproducibility of the patients' setup for 3DCRT and IMRT. The results show that the localization errors are 0.8$\pm$0.2 mm (AP) and 1.0$\pm$0.3 mm (Lateral) in the cases relating to the brain and 1.1$\pm$0.5 mm (AP) and 1.0$\pm$0.6 mm (Lateral) in the cases relating to the pelvis. The reproducibility of the patients' setup was verified by visualization, using real-time image acquisition, leading to the practical utilization of our software Conclusions : A PSVT system was developed for the verification of the alignment between machine and the target isocenters, and the reproduclbility of the patients' setup in 3DCRT and IMRT. With adjustment of the completed GUI-based algorithm, and a good quality DRR image, our software may be used for clinical applications.

Some Issues on China General Aviation Legislation (中國通用航空立法若干問題研究)

  • Shuang, Luan
    • The Korean Journal of Air & Space Law and Policy
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    • v.31 no.2
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    • pp.99-143
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    • 2016
  • General aviation and air transport are two wings of the civil aviation industry. Chinese air transport is developing rapidly, and has become the world second air transport system only second to US since 2005. However, Chinese civil aviation is far behind the world average level, and cannot meet requirements of economic construction and social development. The transition and structural adjustment of Chinese economy provide the general aviation with a unprecedented broad market. The prospect of general aviation is promising and anticipated. The development of general aviation industry needs the legislative supports, and the current legislative conditions of Chinese general aviation are undoubtedly far behind the realistic requirements. Accelerating the legislation in Chinese general aviation industry requires scientific legislation concept. First, Legislation must promote development of general aviation industry. The general aviation will serves as a Chinese emerging industry that boosts domestic demand, promotes employment and expedite domestic economic development. We should, based on both the concept of promoting the industrial development of general aviation and national industrial planning, enact and rectify relative laws and regulations. And we should also straighten out the relationship between aviation security and industrial development and promote the revolution of low-altitude airspace management in an all-round way, in order to improve the utilization rate of airspace resources, classify and establish airspace, simplify examination and approval procedure and intensify operation management. In addition, what we should do is to expedite the infrastructure layout construction, guide the differentiated but coordinated development of general aviation industries in various areas, establish a united supervision mechanism of general aviation, redistrict the responsibilities of Chinese Air Control Agency and set up legislation, law enforcement and judicial systems with clarified institutions, clear positioning and classified responsibilities, so as to usher in a new era of the legislative management of Chinese general aviation industry. Second, shift the focus from regulations to both regulations and services. Considering the particularity of the general aviation, we should use American practices for reference and take into account both regulation and service functions when enacting general aviation laws. For example, we should reduce administrative licensing and market supervision, and adopt "criteria" and "approval" management systems for non-commercial and commercial aviation. Furthermore, pay attention to social benefits. Complete social rescuing mechanism through legislation. It should be clarified in legislation that general aviation operators should take the responsibilities of, and ensure to realize social benefits of environmental protection and ecological balance .Finally, rise in line with international standards. Modify Chinese regulations which is inconsistent with international ones to remove barriers to international cooperation. Specify basic legislative principles. One is the principle of coordination. Realize coordination between the civil aviation and general aviation, between military aviation and civil aviation, and among departments. Two is the principle of pertinence. The general aviation has its own rules and specialties, needing to be standardized using specialized laws and regulations. Three is the principle of efficiency. To realize time and space values of general aviation, we should complete rules in aerospace openness, general aviation airport construction, general aviation operations, and regulation enforcement. Four is the principle of security. Balance the maximum use of resources of Chinese airspace and the according potential threats to Chinese national interests and social security, and establish a complete insurance system which functions as security defense and indemnificatory measure. Establish a unified legal system. Currently, the system of Chinese general aviation laws consists of national legislation, administrative laws and regulations and civil aviation regulations (CAR). Some problems exist in three components of the system, including too general content, unclear guarantee measures, incomplete implementation details, and lacking corresponding pertinence and flexibility required by general aviation regulations, stringency of operation management and standards, and uniformity of standards. A law and regulation system, centered on laws and consisting of administrative laws regulations, industrial regulations, implementation details, industrial policies and local laws and regulations, should be established. It is suggested to modify the Civil Aviation Law to make general aviation laws complete, enact the Regulations of General Aviation Development, and accelerate the establishment, modification and abolition of Chinese general aviation laws to intensify the coordination and uniformity of regulations.

Low temperature plasma deposition of microcrystalline silicon thin films for active matrix displays: opportunities and challenges

  • Cabarrocas, Pere Roca I;Abramov, Alexey;Pham, Nans;Djeridane, Yassine;Moustapha, Oumkelthoum;Bonnassieux, Yvan;Girotra, Kunal;Chen, Hong;Park, Seung-Kyu;Park, Kyong-Tae;Huh, Jong-Moo;Choi, Joon-Hoo;Kim, Chi-Woo;Lee, Jin-Seok;Souk, Jun-H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.107-108
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    • 2008
  • The spectacular development of AMLCDs, been made possible by a-Si:H technology, still faces two major drawbacks due to the intrinsic structure of a-Si:H, namely a low mobility and most important a shift of the transfer characteristics of the TFTs when submitted to bias stress. This has lead to strong research in the crystallization of a-Si:H films by laser and furnace annealing to produce polycrystalline silicon TFTs. While these devices show improved mobility and stability, they suffer from uniformity over large areas and increased cost. In the last decade we have focused on microcrystalline silicon (${\mu}c$-Si:H) for bottom gate TFTs, which can hopefully meet all the requirements for mass production of large area AMOLED displays [1,2]. In this presentation we will focus on the transfer of a deposition process based on the use of $SiF_4$-Ar-$H_2$ mixtures from a small area research laboratory reactor into an industrial gen 1 AKT reactor. We will first discuss on the optimization of the process conditions leading to fully crystallized films without any amorphous incubation layer, suitable for bottom gate TFTS, as well as on the use of plasma diagnostics to increase the deposition rate up to 0.5 nm/s [3]. The use of silicon nanocrystals appears as an elegant way to circumvent the opposite requirements of a high deposition rate and a fully crystallized interface [4]. The optimized process conditions are transferred to large area substrates in an industrial environment, on which some process adjustment was required to reproduce the material properties achieved in the laboratory scale reactor. For optimized process conditions, the homogeneity of the optical and electronic properties of the ${\mu}c$-Si:H films deposited on $300{\times}400\;mm$ substrates was checked by a set of complementary techniques. Spectroscopic ellipsometry, Raman spectroscopy, dark conductivity, time resolved microwave conductivity and hydrogen evolution measurements allowed demonstrating an excellent homogeneity in the structure and transport properties of the films. On the basis of these results, optimized process conditions were applied to TFTs, for which both bottom gate and top gate structures were studied aiming to achieve characteristics suitable for driving AMOLED displays. Results on the homogeneity of the TFT characteristics over the large area substrates and stability will be presented, as well as their application as a backplane for an AMOLED display.

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A Dynamic Behavior Evaluation of the Curved Rail according to Lateral Spring Stiffness of Track System (궤도시스템의 횡탄성에 따른 곡선부 레일의 동적거동평가)

  • Kim, Bag-Jin;Choi, Jung-Youl;Chun, Dae-Sung;Eom, Mac;Kang, Yun-Suk;Park, Yong-Gul
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.517-528
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    • 2007
  • Domestic or international existing researches regarding rail damage factors are focused on laying, vehicle conditions, driving speed and driving habits and overlook characteristics of track structure (elasticity, maintenance etc). Also in ballast track, as there is no special lateral spring stiffness of track also called as ballast lateral resistance in concrete track, generally, existing study shows concrete track has 2 time shorter life cycle for rail replacement than ballast track due to abrasion. As a result of domestic concrete track design and operation performance review, concrete track elasticity is lower than track elasticity of ballast track resulting higher damage on rail and tracks. Generally, concrete track has advantage in track elasticity adjustment than ballast track and in case of Europe, in concrete track design, it is recommended to have same or higher performance range of vertical elastic stiffness of ballast track but domestically or internationally review on lateral spring stiffness of track is very minimal. Therefore, through analysis of service line track on site measurement and analysis on performance of maintenance, in this research, dynamic characteristic behaviors of commonly used ballast and concrete track are studied to infer elasticity of service line track and experimentally prove effects of track lateral spring stiffness that influence curved rail damage as well as correlation between track elasticity by track system and rail damage to propose importance of appropriate elastic stiffness level for concrete and ballast track.

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The Study on Musculoskeletal Symptoms and it's Related Factors in Radio-Technologists (방사선사의 근골격계 증상과 유해 요인에 관한 연구)

  • Lee, Hyang-Seob;Han, Man-Seok
    • Journal of radiological science and technology
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    • v.31 no.3
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    • pp.239-247
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    • 2008
  • In order to study the occurrence of symptoms of musculoskeletal disorders of radio-technologists employed at metropolitan general hospitals and the factors that influence such occurrence, standardized questionnaire by NIOSH that was modified and supplemented to be suitable for conditions in Korea was used. Answers collected from 143 radio-technologists in two weeks from June 13, 2007 were analyzed and the results are as follows. Factor that influence symptoms of musculoskeletal disorders by area were analyzed through multiple logistic regression analysis and the results found that in the neck area, risk increased as the burdening work category 2(Korea ministry of labor)(OR=3.94) and burdening work category 9(Korea ministry of labor)(OR=4.72) increased. In the shoulder region, risk increased as burdening work category 2(Korea ministry of labor)(OR=5.36), burdening work category 7(Korea ministry of labor)(OR=3.90), and burdening work category 9 (Korea ministry of labor)(OR=5.76) increased. In the arm/hand/wrist regions, risk increased as burdening work category 2 (Korea ministry of labor) (OR=6.91), and burdening work category 9 (Korea ministry of labor)(OR=3.76) increased. In the lower back region, risk increased as burdening work category 2 (Korea ministry of labor) (OR=3.06), and burdening work category 8 (Korea ministry of labor)(OR=8.14) increased. In the leg/knees/foot regions, risk increased as burdening work category 2 (Korea ministry of labor) (OR=3.63), and burdening work category 9 (Korea ministry of labor)(OR=2.96) increased. Conclusively, in factors that influence musculoskeletal disorder symptoms in radio-technologists, influence of subjective health conditions, total work experience, experience in current division, and burdening work category 2, 7, 8, and 9 (Korea ministry of labor) were most significant. Therefore, for preventive management, in addition to ergonomic and educational intervention for correcting improper posture during work, efforts for break time adjustment and stress reduction is needed, and encouragement and support for regular exercise is needed.

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Factors Influencing the Adoption of Location-Based Smartphone Applications: An Application of the Privacy Calculus Model (스마트폰 위치기반 어플리케이션의 이용의도에 영향을 미치는 요인: 프라이버시 계산 모형의 적용)

  • Cha, Hoon S.
    • Asia pacific journal of information systems
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    • v.22 no.4
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    • pp.7-29
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    • 2012
  • Smartphone and its applications (i.e. apps) are increasingly penetrating consumer markets. According to a recent report from Korea Communications Commission, nearly 50% of mobile subscribers in South Korea are smartphone users that accounts for over 25 million people. In particular, the importance of smartphone has risen as a geospatially-aware device that provides various location-based services (LBS) equipped with GPS capability. The popular LBS include map and navigation, traffic and transportation updates, shopping and coupon services, and location-sensitive social network services. Overall, the emerging location-based smartphone apps (LBA) offer significant value by providing greater connectivity, personalization, and information and entertainment in a location-specific context. Conversely, the rapid growth of LBA and their benefits have been accompanied by concerns over the collection and dissemination of individual users' personal information through ongoing tracking of their location, identity, preferences, and social behaviors. The majority of LBA users tend to agree and consent to the LBA provider's terms and privacy policy on use of location data to get the immediate services. This tendency further increases the potential risks of unprotected exposure of personal information and serious invasion and breaches of individual privacy. To address the complex issues surrounding LBA particularly from the user's behavioral perspective, this study applied the privacy calculus model (PCM) to explore the factors that influence the adoption of LBA. According to PCM, consumers are engaged in a dynamic adjustment process in which privacy risks are weighted against benefits of information disclosure. Consistent with the principal notion of PCM, we investigated how individual users make a risk-benefit assessment under which personalized service and locatability act as benefit-side factors and information privacy risks act as a risk-side factor accompanying LBA adoption. In addition, we consider the moderating role of trust on the service providers in the prohibiting effects of privacy risks on user intention to adopt LBA. Further we include perceived ease of use and usefulness as additional constructs to examine whether the technology acceptance model (TAM) can be applied in the context of LBA adoption. The research model with ten (10) hypotheses was tested using data gathered from 98 respondents through a quasi-experimental survey method. During the survey, each participant was asked to navigate the website where the experimental simulation of a LBA allows the participant to purchase time-and-location sensitive discounted tickets for nearby stores. Structural equations modeling using partial least square validated the instrument and the proposed model. The results showed that six (6) out of ten (10) hypotheses were supported. On the subject of the core PCM, H2 (locatability ${\rightarrow}$ intention to use LBA) and H3 (privacy risks ${\rightarrow}$ intention to use LBA) were supported, while H1 (personalization ${\rightarrow}$ intention to use LBA) was not supported. Further, we could not any interaction effects (personalization X privacy risks, H4 & locatability X privacy risks, H5) on the intention to use LBA. In terms of privacy risks and trust, as mentioned above we found the significant negative influence from privacy risks on intention to use (H3), but positive influence from trust, which supported H6 (trust ${\rightarrow}$ intention to use LBA). The moderating effect of trust on the negative relationship between privacy risks and intention to use LBA was tested and confirmed by supporting H7 (privacy risks X trust ${\rightarrow}$ intention to use LBA). The two hypotheses regarding to the TAM, including H8 (perceived ease of use ${\rightarrow}$ perceived usefulness) and H9 (perceived ease of use ${\rightarrow}$ intention to use LBA) were supported; however, H10 (perceived effectiveness ${\rightarrow}$ intention to use LBA) was not supported. Results of this study offer the following key findings and implications. First the application of PCM was found to be a good analysis framework in the context of LBA adoption. Many of the hypotheses in the model were confirmed and the high value of $R^2$ (i.,e., 51%) indicated a good fit of the model. In particular, locatability and privacy risks are found to be the appropriate PCM-based antecedent variables. Second, the existence of moderating effect of trust on service provider suggests that the same marginal change in the level of privacy risks may differentially influence the intention to use LBA. That is, while the privacy risks increasingly become important social issues and will negatively influence the intention to use LBA, it is critical for LBA providers to build consumer trust and confidence to successfully mitigate this negative impact. Lastly, we could not find sufficient evidence that the intention to use LBA is influenced by perceived usefulness, which has been very well supported in most previous TAM research. This may suggest that more future research should examine the validity of applying TAM and further extend or modify it in the context of LBA or other similar smartphone apps.

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Inferential Structure and Reality Problem in Diagnosis of Oriental Medicine (한의 진단의 추론형식과 실재성)

  • Park, Geong-Mo;Choi, Seong-Hoon;Ahn, Gyu-Seok
    • Journal of The Association for Neo Medicine
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    • v.2 no.1
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    • pp.55-84
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    • 1997
  • Inferential structure and reality problem is a serious issue to O.M.(oriental medicine). The study will analyze this issue through a philosophical and historical comparative study of W.M.M(Western modern medicine) and O.M. First, I presuppose some basic ideas. The first is the division of the 'the philosophy of medicine' and 'the medicine itself'. Second, there is a 'visibility' that discriminate between 'the abstractive concept' and 'the concrete object' in diagnostic terminology. The third is the separation of disease, the entity and disease, the phenomenon. Finally, the distinction between the cause of disease and the nature of disease. Through these basic concepts, this study will analyze O.M's diagnostic methodology, 'Pattern identification of the S.A.S(sign and symptom)'. The results are follows: 1. O.M's views disease as a phenomenon. So, the S.A.S, which is visible, is the disease itself. Tough the analysis and inference of the S.A.S, 證(zheng) the essence is derived. 2. 證(zheng) can be considered as 'the abstractive concept' reflecting the essence of a disease. 3. 證(zheng) is not arrived through causal sequence reasoning but rather by analogical reasoning. 4. 證(zheng) is 'the non-random correlative combination of S.A.S', pattern. These patterns secure the abstractive deduction in reality. that is, The causality, the positivism, the view of disease as entity, and anatomical knowledge are the traits peculiar to W.M.M. But, these properties can not be applied universally to every medical systems. Also, these properties do not indicate the superiority or inferiority of any medical system. 5. 證(zheng) summarizes the patients condition simultaneously with the S.A.S. However, 證(zheng) doesn't necessarily indicate the knowledge about the actual internal organ. That is, Early in O.M.'s history, the diagnostic terminologies including 證(zheng) were analogical reflections of a naive knowledge of internal organs and external environmental factors. Later, the naive knowledge in 證(zheng) changed int new nature, an abstractive concept. The confusion of the concept of disease, the indiscriminate acceptance of Western anatomical knowledge, and the O.M.'s theoretical evolution et are the challenge facing modern O.M. To find solutions, this study looks at the sequence of the birth of W.M.M. and then compares it's system with the O.M. system. The confusion of the concept of disease, the indiscriminate acceptance of Western anatomical knowledge, and the O.M.'s theoretical evolution et are the challenge facing modern O.M. To find solutions, this study looks at the sequence of the birth of W.M.M. and then compares it's system with the O.M. system. It is recommended that O.M. diagnostics should pay close attention to the ambiguity of the diagnostic methodology in order to further development. At present time, the concept and the system peculiar to O.M. can not be explained by common language. but O.M.'s practitioner can not persist in this manner an: longer. Along with the internal development of O.M., the adjustment of O.M.'s diagnostic terminology needs to be adopted.

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Half a cenury of the rural geography in Korea(1945-1995):review and prospect (촌락지리학 50년(1945-1995)의 회고와 전망)

  • ;Lee, Moon-Jong
    • Journal of the Korean Geographical Society
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    • v.31 no.2
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    • pp.213-254
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    • 1996
  • The Korean Geographical Society was founded in 1945, when Korea was liberated from the Japanese rule. And The Journal of the Korean Geography activated academic studies of geography by publishing research papers in it. Professor Kang, Dae-Hyun wrote the first two specialized papers of rural geography in 1966: " Flood Plain Settlements on the Han River" and "The Location and Form of the Dispersed Villages around Dae-Cwan-Ryung". The early studies of rural geography were not based on serious academic foundations, such as the adjustment of theoretical notions and a good grasp of subjects. After choosing subjects that came to hand without academic consideration. they simply enumerated generalized items of the results of the field work investigation such as the location the landscape and the process of formation of the settlements. In the 1970s and 1980s, however, rural settlement studies progressed remarkably in Korea. More than 80% of 318 dissertations, theses, or papers collected for this review were written in the late 1980s, and the subjects and methodology became diversified. As may be expected, recent studies are found very systematic and problem-solving in the various fields - contexual understanding spatial structure, the development of clan villages according to the socialization process, the effects of rural-out migration on the change of villages etc. Such a trend can be understood as a reaction to the circumstances under which, as the Western society already experienced, rural villages become washed out by the waves of industralization and urbanization and hardly continue to exist. In this paper, geographical studies of rural settlement which have been carried out in Korea last fifty years will be reviewed under the four headings on the studies related to a) farming villages; b) fishing villages; c) mountain villages: and d) special function villages. Studies of farming villages and related ones are very diverse. The results of the studies carried out last fifty years can be classified into sixteen subjects. Just as, in the West, studies of rural settlement have been mainly concerned with farming villages since rural geography came into being, so, in Korea, they have been centred on farming villages. It is a natural result considering the history of human life. Even in Korea, however the rural settlement is no more an isolated life space which keeps unique traditions of old life style, but it begins to form a dynamic life space connected to big cities by heavy traffic. Because the modern farming villages of Korea have an undetachable connection with the cities, special methodology to solve new problems has been posed in the studies of rural settlement. Many scholars have produced a lot of studies of farming villages, and three of them are prominent: Oh. Hong-Seok, Choi, Ki-Yeop, and Lee, Moon-Jong. Oh, Hong-Seok is a versatile and hard-working scholar who has published more papers than anyone else in the various fields of rural geography such as farming villages, fishing villages, mountain villages, and reclamation villages. And he has expanded his concerns to environment issues in recent years. Choi, Ki-Yeop has maintained that the prototype of Korean rural villages is clan villages continuing to write a series of good papers in which he pursues their regionalizion in the process of socialization. Lee, Moon-Jong divides the spatial organization of side settlement, sahachon (settlement near the temple), religion settlement, orchard settlement, settlement near the foreign military camp, displaced people's settlement. Chung Gam Lok settlement, etc. Though The Korean Geographical Society has half a century's history, academic activties in the field of rural settlement have been performed no more than thirty years. We cannot help saying that it is admirable that in such a rather short time we have five academical schools of the rural geography in Korea. geography in Korea.

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A Study on the Relationship between the Disc of Least Confusion and Corrected Vision of Astigmatism (난시안의 최소착락원과 교정시력과의 관계 연구)

  • Kim, Jung-Hee;Kim, In-Suk
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.2
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    • pp.51-57
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    • 2008
  • Purpose: This study has been conducted to know how the size and position of the circle of least confusion has an influence on the vision for minimization of asthenopia when astigmatism is corrected and appropriated prescription to provided clear vision life. Methods: The method of the study has been worked on 68 students (136 eyes) of man and woman enrolled in university of Gyeong-gi-do aged 20 to 40, who have myopic astigmatism in order to know how the corrected vision changes according to the size and position of the circle of least confusion of astigmatism, the vision has been tested by giving the vision whose astigmatic power of 0.25D and 0.50D was just reduced, low correcting the astigmatic power into 0.50D, and at the same time inserting additionally spherical power -0.25D, all under a condition that the corrected vision after completely corrected astigmatism, and the axis of astigmatism was not changed. Results: The average vision was 1.047 when the astigmatic power was fully corrected, and in low correction of 0.25D, it was 0.914, and in low correction of 0.50, it was 0.772. It has been learned that the bigger the circle of least confusion was the bigger the range of vision reduction and the corrected vision in astigmatism has correlation with the size of the circle of least confusion. It has been examined that the average vision according to position of the circle of least confusion in astigmatism was 1.047 when the astigmatic power was completely corrected and focused on the retina with state of point, and in case that the astigmatic power was 0.50D of state of low correction, that is, the circle of least confusion was focused before retina, it was 0.828, and it was also 0.826 when the astigmatic power is low corrected with 0.50D and the circle of least confusion was focused on the retina. Explained briefly, It has been examined that in case that the state of low correction of the astigmatic power was same, the vision reduction was less in the image of the circle of least confusion focused upon the retina than in the image of its being focused before the retina. Conclusions: In case that the refractive power of cylindrical lens is reduced in test of wearability in astigmatism, there needs surely an adjustment of spherical lens that can place the circle of least confusion on the retina.

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