• The Transactions of the Korea Information Processing Society
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• v.6 no.3
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• pp.664-671
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• 1999

Itakura and Nakamura proposed the first multisignature scheme based on RSA signature scheme. But if many users sign on one paper, then their scheme has a reblocking problem. In 1991, Ohta and Okamoto proposed a multisignature scheme by using Fiat-Shamir signature scheme. But in this scheme, the group of signers must generate common random number in the first round, and in the second round, they sign the message with common random number. Also L.Harn proposed a multsignature scheme which is based on the ElGamal's. In korea, S.D.Kim et al. at ICEIC'95 conference, proposed an efficient sequential multisignature scheme by using the modified Park-Won scheme. This scheme is not require an additional round to generate common random number, and has fixed signature length. In this paper, we analyze problem of Kim's multisignature scheme, and propose a new multisignature scheme based on ${\gamma}$\ulcorner residuosity problem.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.49-52
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• 2008

The numerical analysis for gas temperature of turbine blade surface has been performed to investigate development of temperature with various blade edge shape. Two different types of the turbine which one is "Sharp" edge and the other is "Round" edge was modeled. Computations have been carried out several turbine rotational speeds in the range from 0 to 10,000 rpm for the each types of turbine edge shape. As a result, the more rotational speed of turbine increased, the more turbine blade's temperature decreased. It is also found that the surface temperature of turbine blades for sharp type edge were lower than the round type edge.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.305-316
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• 2007

Free field ground motion during earthquake is significantly affected by the local soil conditions and it is essential for the seismic design to perform the site specific ground response analysis. So, Round Robin Test (RRT) on ground response analysis was performed for three sites in Korea. A total of 12 teams presented the results of ground response analysis with used input soil properties based on own judgement. In this paper, the results of one dimensional equivalent linear analysis presented by 11 teams were compared to evaluate the effect of input soil properties on ground response analysis. Additionally, 4 influence factors on ground response analysis, that is shear wave velocity of soil layer, nonlinear dynamic deformational characteristics, bedrock depth and bedrock velocity were studied for assumed simple soil conditions.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.259-265
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• 2007

The technical committee of Soil Dynamics and Geotechnical Earthquake Engineering of Korean Geotechnical Socity has conducted Round Robin Test(RRT) on seismic ground response analyses in 2007. Total 14 participating teams were given exact same soil information of three sites and three input ground motions including two recorded ground motions and one synthetic ground motion. Each team selected its own analysis method and approaches to perform ground response analyses. There were equivalent linear, nonlinear total stress, and nonlinear effective stress approaches, which could be selected. The results from RRT were systematically analyzed and dispersion and variation due to analysis methods, input ground motions, shear velocity profiles, shear modulus reduction curves, damping curves, and other input data are reported by the companion papers.

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.488-496
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• 1998

Somatotropes, mammotropes and somatomammotropes of the Korean native goat hypophysis were studied by double immunoelectron microscopy using antisera to growth hormone(GH) and prolactin(PRL), and protein A-gold particles of different sizes. Mammotropes were round or oval in shape, and contained round and electron dense secretory granules. The size of secretory granules was variable from 460nm to 680nm in diameter. Somatotropes were elliptical or triangular in shape and the oval nucei were located eccentrically at the periphery of the cell. Secretory granules of the cell were oval in shape and clearly distinguished from round granules of mammotropes. The size of granules was 320~680nm in diameter, smaller than that of mammotropes. Somatomammotropes contained round or oval secretory granules. The granules had intermediate size between somatotropes and mammotropes. Some of granules contained both GH and PRL, while the others contained only one of them.

• Journal of Biosystems Engineering
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• v.34 no.4
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• pp.228-233
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• 2009

In order to cut the round bale easily, a roughage cut-feeder for the round bale was developed in this study. This study consists of two parts. One is development of a cutting mechanism and a performance test reported in the previous paper. This is the second part of the study. For the study, recent trend of traditional cutting system was analyzed. Also, cost of the prototype cut-feeder was analyzed and determine the break-even point of farm size was determined by comparing with traditional method using a traditional cutter. A prototype cut-feeder was investigated with the fact that working performance, fiber length and shape of roughage and feeding quality was good. Operating cost of the prototype cut-feeder decreased rapidly with an increase of farm size. Break-even point in terms of farm size was 36 heads for beef and 28 heads for dairy. Also, costs estimated were 118,000 won/head year and 148,000 won/head year, respectively.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.14 no.3
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• pp.107-115
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• 2004

SHACAL-2 is a 256 bit block cipher with various key sizes based on the hash function SHA-2. Recently, it was recommended as one of the NESSIE selections. UP to now, no security flaws have been found in SHACAL-2. In this paper, we discuss the security of SHACAL-2 against an impossible differential attack. We propose two types of 14 round impossible characteristics and using them we attack 30 round SHACAL-2 with 512 bit 18y. This attack requires 744 chosen plaintexs and has time complexity of 2$^{495.1}$ 30 round SHACAL-2 encryptions.

• Journal of the Korean Society of Costume
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• v.63 no.7
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• pp.164-175
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• 2013

This study examined the Yemou(a hat for a dead woman) from the ladies' clothes excavated from the Lady Lee's tomb in order to trace the significance of the clothing composition and its social origin in the Chosun dynasty. The compositional characteristic of Yemou covers the body of the hat which is not connected with the cover, Wonsal which has a round shape that covers the face of the dead body, and two Gae(a ribbon on the backside of a hat). Seongho Lee-ik(one of representative Confucian scholars in the Chosun dynasty) stated in his book entitled "Seongho Notes", that the structural elements of Yemou originated in Yum(wrapping cloth for the head of a dead body). According to Seongho, Yemou's body part came from the scarf used to cover the head. Wonsal(the cloth of round shape for covering the face) and Gae were derived from Yum made of two ends of long cloth for covering and binding the head of a dead body. Yongjae Kim-kunhang(one of Confucian scholars in the late-Chosun dynasty) demonstrated in his "Yongjae Collection" the social background of the emergence of Yemou. Yemou was the hat produced from the process of nationalizing the Chinese courtesy of clothing. In other words, Bokgun(a man's hat) in the Chosun dynasty replaced the Chinese Yum. Unlike the Chinese custom, man and woman in the Chosun dynasty wore different clothes respectively. According to the clothing custom of the Chosun dynasty a woman wore a female hat, Yemou instead of men's Bokgun.

• Applied Microscopy
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• v.14 no.2
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• pp.52-65
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• 1984

The ultrastructure of the pars distalis of the adenohypophysis was studied in the female Korean native goat ($10{\sim}16kg$, B.W.) by electron microscopy. Six granular cells and one agranular cell were recognized according to the characteristic patterns of secretory granules and cell organelles. Type I cells were. large, round or oval and contained the largest granules of 290 to 490 nm in diameter, Their endoplasmic reticula were well developed and packed with parallel lamellae close to nuclear membrane. Type II cells were elongate or polygonal. They contained granules of 220 to 390 nm in diameter and well developed Golgi complex. Type III cells were round, oval or angular and contained granules of 150 to 300 nm in diameter. Their endoplasmic reticula were coarsely scattered among the granules and provided an intracellular compartment for segregation in groups. Type IV cells were oval or round and contained granules of 120 to 280 nm in diameter. Their endoplasmic reticula were arranged at one pole of cytoplasm. Type V cells were round or polygonal and contained small granules of 110 to 140 nm in diameter Their endoplasmic reticula were packed with regularly parallel lamellae. Type VI cells were stellate and irregular in shape and had cytoplasmic processes projecting between the neighboring cells. Their granules were less than 130 nm in diameter, the smallest among the cells of the pars distalis. Agranular cells had no granules or a few, if any. They were stellate or irregular in shape.

• Korean Journal of Clinical Pharmacy
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• v.26 no.3
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• pp.254-263
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• 2016

Objective: Written information could be helpful for senior population to adhere to complex medication therapies, but must be well prepared and empirically assessed to achieve such end. We purposed to develop a drug information leaflet for senior citizens by applying 'performance-based user-testing.' Methods: We employed a user-testing, a mixed method to figure difficulties out with patients' leaflets from the user perspective. The cycle made of test and revision can be repeated as necessary. We recruited senior citizens with age of 65 or above who were taking antihypertensive medications at the point of participating and excluded the elderly who suffered illiteracy. We firstly rectified a drug information leaflet of antihypertensive medications for the general public distributed by the Korean authority based on focus group interviews (9 participants). The revised leaflets were tested four times with 8~12 participants in each round (40 seniors in total). We targeted to develop a leaflet which more than 80% of participants understood 10 key information. Main outcomes measures were to be able to find information and be able to understand information. This study was approved by the Yeungnam University Research Ethics Committee. Results: Focus group interviews identified difficulties with small font of words, professional language, long information, and a poor structure. The leaflet was revised and in the first round questionnaire found problems with 4/10 information points; interviews disclosed all but one (normal blood pressure range) were ill-understood. The second round questionnaire and interview found fewer problems but the comprehensiveness of participants was still poor in several points. For the third and fourth rounds we revised the leaflets in the individual-targeted manner. Finally, the fourth round showed all key information found and understood by at least 80% of participants except one question about drug name. Conclusion: The drug leaflets need to be developed in a personalized mode for the seniors. There was a limit for Korean seniors to understand nonproprietary name of their drugs because they used to producers' trade names which the Korean health system predominantly works with.