• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.1
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• pp.64-77
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• 2009

A proxy re-encryption scheme allows Alice to temporarily delegate the decryption rights to Bob via a proxy. Alice gives the proxy a re-encryption key so that the proxy can convert a ciphertext for Alice into the ciphertext for Bob. Recently, ID-based proxy re-encryption schemes are receiving considerable attention for a variety of applications such as distributed storage, DRM, and email-forwarding system. And a non-interactive identity-based proxy re-encryption scheme was proposed for achieving CCA-security by Green and Ateniese. In the paper, we show that the identity-based proxy re-encryption scheme is unfortunately vulnerable to a collusion attack. The collusion of a proxy and a malicious user enables two parties to derive other honest users' private keys and thereby decrypt ciphertexts intended for only the honest user. To solve this problem, we propose two ID-based proxy re-encryption scheme schemes, which are proved secure under CPA and CCA in the random oracle model. For achieving CCA-security, we present self-authentication tag based on short signature. Important features of proposed scheme is that ciphertext structure is preserved after the ciphertext is re-encrypted. Therefore it does not lead to ciphertext expansion. And there is no limitation on the number of re-encryption.

• Fire Science and Engineering
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• v.25 no.4
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• pp.103-109
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• 2011

In this study, we calculated the smoke movement at the fire area of the refuge floor which has the refuge safety area in case of fire in the high rise building by using a computational fluid dynamics (CFD) code of FLUENT (ver. 13.0). The buoyancy plume was applied using the temperature and flow velocity which represent 10 MW heat release rate in order to describe the fire, and the smoke movement was predicted using a species conservation equation. The pressurization system of smoke control was adopted with smoke control damper in refuge safety area, at the result, it is confirmed that the damper capacity was enough to smoke control in which the flow rate of supply was applied 25 $m^3/s$ in the case of the door at fire area opened only, and 50 $m^3/s$ in the doors at the fire area and lobby both opened case. They were satisfied in NFSC 501-A. Even though the door of fire area closed, there were smoke leakages at the gap between the door and wall. In addition, the refugee could be isolated in the fire area when the door of fire area closed during smoke control in the case of using the high damper flow rate of supply, 50 $m^3/s$. Therefore the proper damper flow rate of supply are needed in order to prevent the damage of refugee and this study proposes the suitable condition of damper capacity according to refuge scenario.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.5
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• pp.339-349
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• 2020

Double-leaf blast-resistant doors consisting of steel box and slab are application-specific structures installed at the entrances of protective facilities. In these structural systems, certain spacing is provided between the door and wall. However, variation in the boundary condition and structural behavior due to this spacing are not properly considered in the explosion analysis and design. In this study, the structural response and failure behavior based on two variables such as the spacing and blast pressure were analyzed using the finite element method. The results revealed that the two variables affected the overall structural behavior such as the maximum and permanent deflections. The degree of contact due to collision between the door and wall and the impact force applied to the door varied according to the spacing. Hence, the shear-failure behavior of the concrete slab was affected by this impact force. Doors with spacing of less than 10 mm were vulnerable to shear failure, and the case of approximately 15-mm spacing was more reasonable for increasing the flexural performance. For further study, tests and numerical research on the structural behavior are needed by considering other variables such as specifications of the structural members and details of the slab shear design.

• Journal of Korean Society of Forest Science
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• v.86 no.1
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• pp.9-16
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• 1997

The contingent valuation method(CVM) has been used to evaluate the economic value of nonmarket goods such as forest recreation. There are two commonly used CVM questionnaire formats: open-ended and closed-ended. This study evaluates the net economic value associated with day use downhill skiing, using CVM. A random, on-site survey of skiers in Muju, Korea generated the value estimates. In this paper a nonparametric test is introduced to find whether the difference between value estimates from open-ended and closed-ended formats are significantly different because the distributions of WTPs are non-normally distributed. The results show that the net economic benefits of a skier in Muju varies from \15,131 to \25,332. The closed-ended values were 1.15 to 1.67 times as large as the open-ended values, depending on the model specifications. In nonparametric test the mean WTPs of the open-ended and close-ended applications are significantly different. Its reason may be that closed-ended can be more reducing the incentive for strategic behavior than open-ended question. However, we cannot conclude that the closed-ended method is superior to the open-ended method.

• Journal of Gifted/Talented Education
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• v.22 no.4
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• pp.893-916
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• 2012

This research investigates gifted students' mothers' rearing stress based on the concept mapping method. For this, 12 gifted students' mothers solicited, gathered and analyzed related statements, and then did multidimensional scaling and hierarchical cluster analysis. The stress value was .273 which was appropriate for the two level concept mapping study. In addition 101 mothers of gifted students rated for the rearing stresses they experience. Results were as follows. First, 79 concrete statements were solicited and as a result of concept mapping were categorized as 'burden and conflict as mothers of the gifted', 'possible negative characteristics due to the giftedness', and 'self-esteem and pressure by the title of the gifted'. Especially following items showed relatively high average: worrying about how to give the child a specific help for his/her career(M=4.65); worrying that she might be intervening too much in their child's behaviors(M=4.60); getting pressured supporting the child to get involved in the gifted education system continually(M=4.46); worrying if her child is not developing his/her talent enough due to the lack of time and money(M=4.44); being concerned that her high expectations might be putting her child under too much pressure (M=4.43). Implications of the study related to gifted education practices were discussed.

• Journal of Korean Philosophical Society
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• v.142
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• pp.295-321
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• 2017

This paper discusses Hegel's concept of Art criticism, focusing on the article "${\ddot{U}}ber$ die Bekehrten" in 16. Vol. of Hegel's Gesammelte Werke. Hegel is a theorist of the system of art, but also an art critic who actively participated in popular art practice. Until now, Hegel has been interpreted mainly as a theorist who usually constitutes the system of art. According to many interpretations, Hegel has been criticized for his theories frame interpretation of the Artwork compulsorily. But in this article we see another aspect of Hegel as an art critic. First, in this article Hegel shows as an art critic how romanticists distort the work with an emphasis on the theory. Hegel argues in his article written in early 1826 that romantic ironic theory does not help at all in understanding the "die Bekehrten" of Laupach. Whereas ironic theory emphasizes the contradiction between character and its action as the essential value of the work, Hegel interprets that the comic is at the center of the work, which lets the unessential sides of the unified character disappear, so that the unity of the character expresses itself. Hegel also interprets that the theory of irony represents the work of art for the scholars, which harms the objectivity of artwork and defends the artwork for the public. Second, Hegel began to apply the achievement of his criticism to his aesthetic lectures. Since 1826 Hegel has focused intensively on discussing two concepts, romantic irony and 'artwork for the public' in his aesthetics lectures. Thus, this article provides a basis for Hegel 's criticism of ironic theory after 1826 and the concept of artwork for the public. In this respect, we can confirm that Hegel has reinforced and extended his theories through his practice of criticism of concrete works of art rather than imposing systematic theories upon art criticism

• Journal of the Korea Convergence Society
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• v.10 no.1
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• pp.95-102
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• 2019

After liberation, several literary groups with the nature of the national culture movement joined in Japan in January 1948 to form the Korean-Japanese Joseon Literary Society. However, the Korean-Japanese Joseon Literary Society was unable to play an active role due to the suppression of the GHQ and gathered again as the Korean War Armistice Agreement was concluded in 1953. The institutional journal of the 'Korean-Japanese Joseon Literary Society' is published by changing the magazine name to "Munhakbo" in Japanese and "Joseon Literature", "Joseon Literature and Arts" in Korean. The national movement group of Korean residents in Japan and literature groups were reorganized in conjunction with the political situation in Japan and the Korean peninsula. The reunion of 'Korean-Japanese Joseon Literary Society' was also based on the appearance of 'Jochongnyeon (pro-Pyeongyang federation of Korean residents in Japan)' and 'conversion of line'. In this paper, we are to fill up the blank of the research on literature of Korean residents in Japan in the 1950s by identifying the reality of conflict between 'Jochongnyeon' and 'Mindan', meaning of 'Korean Writing' Movement as a subject of national movement and the issue of promoting self-esteem as a 'citizen of the Republic' that 'Korean-Japanese Joseon Literary Society' tried to convey to Korean readers in Japan.

• Korean Journal of Ichthyology
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• v.31 no.3
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• pp.150-158
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• 2019

We examined the food habits of larval Acanthogobius flavimanus using 260 specimens collected from February to April 2011 in the Nakdong River estuary, Korea. We found that larval A. flavimanus are carnivorous, feeding mainly on copepods and tintinnids. Their diet also included small quantities of larval polychaetes, macrostomids, larval bivalves, rotifers, barnacles, diatoms and unidentified materials. To assess ontogenetic changes in diet composition, the larvae were separated into three developmental stages: preflexion (<7 mmNL), flexion (7~9 mmNL), and postflexion (>9 mmNL). The preflexion group frequently preyed on tintinnids. But as the larvae of A. flavimanus grew, the consumption of copepods for flexion group, and polychaetes for postflexion group, increased respectively. The larvae of A. flavimanus showed one peak for feeding incidence at dusk, but the mean number of preys per individual was high until midnight.

• Korean Journal of Medical Ethics
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• v.21 no.4
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• pp.344-359
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• 2018

The purpose of this study was to identify how patients with chronic kidney disease understand informed consent and related factors for clinical trials. Data from a paper-based survey was collected from July 1, 2017 to April 30, 2018. The subjects for this study were 85 adult patients with chronic kidney disease who were participating in clinical trials. Surveys were conducted by a tool modified from QuIC as designated by Joffe in 2001. The QuIC consists of two parts: objective and subjective cognition. These tools were modified for this study. The average score for the objective understanding (OU) of informed consent for clinical trials was 69.56; the average score for the subjective understanding (SU) of informed consent for clinical trials was 3.28. It was found that health literacy predicted OU (F=27.709, p<.001) while SU was predicted by additional information (F=-3.095, p<.003), question (F=13.603, p<.001), and informed consent (F=-4.833, p<.001). In conclusion, the results of this study indicate that the understanding of informed consent for clinical trials among patients with chronic kidney disease is relatively low. Accordingly, alternative methods that consider each patient's health literacy levels and related factors need to be considered in order to improve their understanding of informed consents during the clinical trial process.

• (The)Study of the Eastern Classic
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• no.35
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• pp.329-358
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• 2009

A general idea and the structure of Wangshouren's philosophy is intimately associated with "Daxue". Systemicity of Wangshouren's Xinxue stand on the basis of a mind, intention, innate knowledge and things. "Daxuewen" is a series of a process of gongfu. It stand on the basis of a mind, intention, innate knowledge and things, same as Four-Sentence Teaching. Wangshouren's gongfu theory of "Daxue" changes from gewu to chengyi, from chengyi to zhizhi again. It is deepening of Wangshouren's philosophy and is the change of education. It is also that Wangshouren's gongfu theory internalize anything. He spent his younger life in pursuit of Zhuxi's gewu. Through a lecture of LongChang, Wangshouren's gongfu theory of "Daxue" changes from extroversion to introversion. According to Wangshouren' opinion, "Daxuewen" is the tenet of the XinXue, same as Four-Sentence Teaching. This papers mainly emphases two points: one, to analyze the thinking system of Wangshouren's "Daxuewen", make a comparative study of befour "Daxuewen" and after "Daxuewen". another, through this work we can understand thoroughly Wangshouren's viewpoint of "Daxue".