• Aerospace Engineering and Technology
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• v.6 no.2
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• pp.134-140
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• 2007

Since the successful launch of Sputnik 1, a rocket engine was evolved rapidly. The first artificial satellite Sputnik has only 182 lb mass with a size of a basket ball, a modern artificial satellite is over 10 tons. As the size and the mass of an artificial satellite increases, the stronger launch vehicles are required. However, the story is different in the field of the rocket engine development. In the early to mid age of the space race, rocket engine study was focused on the stronger and bigger engine development, but from the 80's the tide has changed. A rocket engine must be strong and also economic. This trend was accelerated from when a rocket launch was used commercially. In this study, a capability of the launch vehicle and engine was investigated to provide a reference for a liquid rocket engine development plan.

• Journal of Environmental Impact Assessment
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• v.9 no.2
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• pp.127-142
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• 2000

This research was performed for analyzing the transport of suspended solids during the harbor construction. In behalf of the research, we have analyzes the characteristics of suspended solids movement in sand reclamation of breakwater according to age of tide and tidal period at the construction spot of Pusan new harbor. In the process of sand reclamation, soil was dumped by a dumping device which direct soil from the barge to the bottom of the sea. According to the results from this research, suspended solid concentration was very high in the range of 5m from the dumping point right after the dumping. However these suspended solids settled very quickly and the solids concentration was very beyond 10m from the dumping point. It is deduced that the movement of solids dumped from barge has the tendencies as following; 1) Most of the dumped solids precipitated quickly after the dumping 2) The rest of the suspended solids are diffused slowly toward the bottom of the water being figured smoothing curve 3) The diffusion movement of suspended solids tend to proceed toward the shore line in a parallel motion with tidal current at the sea-bottom That is to say, most of the suspended solids precipitated very quickly even though highly concentrated solids produced at the bottom of the solids which did not precipitated spread with the tidal current horizontally along the bottom of the sea.

• Journal of Microbiology
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• v.42 no.2
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• pp.117-125
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• 2004

Propionibacterium acnes (P. acnes) plays an important role in the disease pathogenesis of acne vulgaris, a disorder of pilosebaceous follicles, seen primarily in the adolescent age group. In the present study, the presence of antibodies against P. acnes (MTCC1951) were detected in acne patient (n=50) and disease free controls (n=25) using dot-ELISA and Western blot assay. The ability of P. acnes to induce pro-inflammatory cytokines by human peripheral blood mononuclear cells (PBMCs), obtained from acne patients and healthy subjects, were also analysed. The patients (n=26) who were culture positive for skin swab culture, were found to have a more advanced disease and higher antibody titres (1:4000 to >1:16000) compared to the P. acnes negative patients (n=24) and normal controls (n=25). An analysis of patients' sera by western blot assay recognized a number of antigenic components of P. acnes, rang-ing from 29 to 205 kDa. The major reactive component was an approximately 96 kDa polypeptide, which was recognised in 92％ (24 of 26) of the patients sera. Further, the P. acnes culture supernatant, crude cell lysate and heat killed P. acnes whole cells, obtained from 72-h incubation culture, were observed to be able to induce significant amounts of IL-8 and tumor necrosis factor alpha (TNF-${\alpha}$) by the PBMCs in both the healthy subjects and patients, as analysed by cytokine-ELISA. The levels of cytokines were significantly higher in the patients than the healthy subjects. A major 96 kDa polypep-tide reactant was eluted from the gel and was found to cause dose dependent stimulation of the pro-ductions of IL-8 and TNF-${\alpha}$. Thus, the above results suggest that both humoral and pro-inflammatory responses play major roles in the pathogenesis of acne.

• Journal of The Geomorphological Association of Korea
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• v.24 no.4
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• pp.27-41
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• 2017

In this study, geomorphological and geological research has been carried out to estimate the possibility of ancient port location near Hwaseong Dangseong. Geomorphological characteristics around Eunsupo were analyzed through comparison of past and present topographic maps and field survey. Grain size, age dating, and geochemical analysis on surface sediments and borehole sediments were performed. Through the geomorphological characteristics analysis, it was interpreted that Eunsupo area was submerged in seawater especially at high tide in the past, and that ships could approach to the inside of the area through the tidal channel which were developed in the area. It is also assumed that ships were anchored at a low elevation point in the area. The paleo-environmental change in the area was analyzed based on the classification of sedimentary environment using grain size distribution of surface and borehole sediments and geochemical analysis. It was confirmed that the geomorphological interpretation for the possibility of ancient port location coincided well with the paleo-environmental change interpreted through sediment analysis. This study is a basic study for estimating ancient port location, and it is expected that more accurate paleo-environmental changes will be restored through detailed geomorphological survey and additional borehole analysis in the future research.

• Journal of The Geomorphological Association of Korea
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• v.18 no.1
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• pp.101-112
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• 2011

Coastal terrace was developed at 7.2m height near Shinchon village in Geoje Island. It is located on the east side of southern coast in Korean Peninsula, where sea-level changes caused by ebb and flow of the tide, embayment are relatively low. Due to the breccia layer by mass-movement, dark grayish clayey formation, marine origin's rounded gravel are deposited sequentially in a cross-section of coastal terrace, so it provides a good example which understand Holocene sea level changes to determine the effect on the various sedimentary environments. For the purpose of identifying the morphogenetic process, Grain size, Roundness, XRD, AMS dating analysis was attempted. As a result, after last glacial age, Holocene sea level rise to +5.6m(4,740±100yrs BP). At that time, various geomorphological features are considered to be formed.

• Journal of Broadcast Engineering
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• v.12 no.5
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• pp.460-479
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• 2007

When culture took large part in industrial area, every country has tried to utilize own cultural contents for educational or commercial purpose and the various cultures and histories are recognized as a main concept or subject so that a number of scholars who study history increase. In video game field, special characteristics of interface that audiences participate in the game to complete story-telling is considered as efficient material for learning process. As observed above, it is important to analyze the games that every country makes and export to the world in which the video games is understood as a play of human in general. This Paper has firstly analyzed the most favorite historical games developed in Korea, the USA, Japan, Taiwan and Germany from 1980 to 2005 and secondly, compared that wars and historical origin appears in game scenario, a world view and background story and finally after point out the preferable era and genre of the countries then propose the promising way of design for historical video games. In the process of analysis of a view and heroes in historical games, we compared the real persons, the real historical events and novel in which 11.8% only employed the real persons in 8 out of 68 games. Also the real history and background story are appeared in 37 games which is 54.4% of them. We discovered that the main material that is popular for each country is the historical backing rather than real persons where the favorite historical background is chosen at which they are proud of; 3-Throne era with strong ancient Gogurye for Korea, the 1st and 2nd World Wars and the Independence War for the USA, the tide of war around Middle age for Japan, ancient history of Europe for Germany. The favorite age for video games is Ancient times with 37 games for 54.4%, Middle Age with 7 games fer 10.3%, the prehistoric age with 5 games for 7.35%, remote age with 1 for 1.47%, while current historical games favor Ancient or Modern Age.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.477-483
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• 1985

This paper describes seasonal changes of total length, hepatosomatic index (HSI), fatness, egg-diameter composition, and fecundity of the longchin goby Chasmichthys dolichognathus(HILGENDORF). The specimens used were captured in the tide pool of Tongbaekseom, Pusan, Korea from February 1983 to January 1984. The age of longchin goby, tested by size frequency, was believed to be usually one year which grows to 8.0 cm in total length. The annual variations of HSI reached the maximum in the early spring when the gonad was actively growing and decreased during the spawning season from April to July. The coefficients of fatness were represented low values for the spawning periods. Frequency distribution of the egg diameter of mature ovary has three modes: one is the evident mode of the ripe eggs group, and the other two are modes of maturing and immature eggs groups. And an individual is considered as spawns one in the spawning season. Relationships between the fish size in total length (TL cm) and the number of ovarian eggs(F), the fish weight (BW g) and the number of ovarian eggs are indicated by the exponential equation respectively : F=42.585 $TL^{1.608}$, F= 524.589 $BW^{0.475}$.

• Korea Journal of Hospital Management
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• v.11 no.1
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• pp.31-53
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• 2006

The objective of this study is to examine the effectiveness of the strategy of hospital specialization by analyzing the differences in expected and perceived services, perceived service quality, satisfaction, and intentions to revisit and recommend the hospital to others between general and specialty hospitals. Data were collected using self-administered questionnaire from patients admitted to four study hospitals: two speciality and two general hospitals. The questionnaire was developed based on SERVQUAL to measure five dimensions of service quality. Four hundreds questionnaires were distributed to inpatients or their guardians and 282 returned questionnaires were used in the analyses. The significance of the differences in study variables between specialty and general hospitals were tested by t-test and $x^2$-test. The factor analysis result confirmed the construct validity of 28 questions asked to measure service quality and resulted in four dimensions of service quality: reliability, assurance, tangible and empathy/responsiveness. Cronbach's Alpha ranged from .9013 to .9358, that confirmed the internal consistency of answers. The study results indicated that patients who used specialty hospitals had higher levels of expected and perceived service, a higher level of perceived service quality, and higher levels of service satisfaction than patients who used general hospitals. Percents of patients who had the intention to revisit the hospital and to recommend the hospital to others were higher among patients in specialty hospitals. The most frequent reason to choose the hospital was the excellence of doctors in both general(29.9%) and specialty(43.8%) hospitals, that was followed by convenient transportation(15.3%) and someone know works at the hospital(15.3%) in general hospitals and other's recommendation(14.6%), and nice amenities(13.1%) in specialty hospitals. Although there were no significant differences in clinical department, age, and sex of patients between general and specialty hospitals, patients who visited speciality hospitals had higher levels of education and income than their counter part in general hospitals. These results suggested that specialty hospitals performed better than general hospitals. Specialization could be a viable strategy to tide over recent financial difficulties experienced by hospitals, particularly small- and medium-sized hospitals.

• 한국해양학회지
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• v.28 no.3
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• pp.212-228
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• 1993

A chenier, about 860 m long, 30 to 60 m wide and 0.6∼1.6 m high, occurs on the upper muddy tidal flat in the Gomso bay, western coast of Korea, It consists of medium to fine sands and shells with small amounts of subangular gravels. Vertical sections across the chenier show gently landward dipping stratifications which include small-scale cross-bedded sets. the most probable source of the chenier is considered to be the intertidal sandy sediments. Vibracores taken along a line transversing the tidal flat reveal that the intertidal sand deposits are more than 5 m thick near the low-water line and become thinner toward the chenier. The most sand deposits are undertrain by tidal muds which occur behind the chenier as salt marsh deposits. C-14 age dating suggests that the sand deposits and the chenier are younger than about 1,800 years B.P. The chenier has originated from the intertidal sand shoals at the lower to mid sand flat, and has continuously moved landward. A series of aerial photographs (1967∼1989) reveal that intertidal sand shoals (predecessor of the western part of chenier) on the mid flat have continuously moved landward during the past two decades and ultimately attached to the eastern part of the chenier already anchored at the present position in the late 1960s. Repeated measurements (four times between 1991 and 1992) of morphological changes of the chenier indicate that the eastern two thirds of the chenier, mostly above the mean high water, has rarely moved whereas the western remainder below the mean high water, has moved continuously at a rate of 0.5 m/mo during the last two years (1991∼1992). This displacement rate has been considerably accelerated up to 1.0 m/mo in winter, and during a few days of typhoon in the summer of 1992 the displacement amounted to about 8∼11 m/mo for the entire chenier. these facts suggest that macro-tidal currents, coupled with winter-storm waves and infrequent strong typhoons, should play a major role for the formation and migration of chenier after 1,800 B.P., when the sea level already rose to the present position and thereafter remained constant.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.12
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• pp.425-435
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• 2018

The purpose of this study is to investigate the cultural value as well as business value of Juk-Bang-Ryeum(fishing instrument made by bamboo weir) by the investigation of remains in Gyeongnam Sacheon area and reviewing various historical literatures. The research will contribute to make back data necessary for the registration of World Heritage(UNESCO) and Globally Important Agricultural Heritage Systems(FAO). Fisheries, along with agriculture, have been great significance in human history. In particular, the Fisheries has been considered very important industry due to the geopolitical characteristics of our country surrounded by the sea. We can imagine may types of fishing practices and instruments at the agricultural age. Nonetheless, there are a few fishery heritages such as collecting and hunting tools that remains today. Fortunately, there are many Juk-Bang-Ryeum which is actually operate now from the past 500 years ago at the The Sacheon and Namhae areas. We could found some literature records about it in the historical ancient literatures. We could also infer that Juk-Bang-Ryeum was an important fishery resource of the country for a long time. It was built on the basis of scientific principles to capture fishes using the rapid tide of the natural geological straits, and it prove the wisdom of our ancestors. We also could found some unique cultural heritages that was important to the local community. Naturally, it has been managed as an important asset for the residents. In addition to such historical and humanistic values, it also has business and educational value. It can be useful to understand scientific fishery principles as well as fishery experience field. It has business value as an important tourism resource in the region in connection with historical relics and geological environment resources. In conclusion, it is a valuable asset to be handed down as a valuable cultural heritage.