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Application Study of $CO_2$ Snow Cleaning for Cleaning of Foreign Matter and Corrosion Products on Iron Artifacts ($CO_2$ Snow Cleaning 적용 철제유물 표면 이물질 제거 연구)

  • Lee, Eun-Ji;Cho, Nam-Chul;Lee, Jong-Myong;Yu, Jae-Eun
    • Journal of Conservation Science
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    • v.27 no.3
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    • pp.333-344
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    • 2011
  • Cleaning of foreign matter and corrosion products on surface among conservation treatment of iron artifacts is an important part for looking up a original form. The sand blaster is the most popular equipment when it removes the foreign matter and corrosion products on iron artifacts surface. Current foreign matter and corrosion products equipment, which mostly uses, is sand blaster. Glass dust which sprayed from sand blaster is harmful and causing environmental pollution. In order to solve these problems, we investigated the $CO_2$ snow cleaning that use a eco-friendly equipment to apply for cleaning foreign matter and corrosion products on surface of iron artifacts. It examined by using sand blaster and $CO_2$ snow cleaning to aged steel coupon and iron artifacts. In case of aged steel coupon, the result showed that the sand blaster and $CO_2$ snow cleaning methods were similar to the degrees of cleaning foreign matter and corrosion products, through surface roughness, color measurement and SEM. $CO_2$ snow cleaning applied to aged steel coupons weren't worn out the surface in comparison with sand blaster by SEM. When applied to the iron artifacts, power nozzle of the $CO_2$ snow cleaning was an excellent cleaning effect that surface wern't worn out in comparison with sand blaster. And, it showed that internal structure change of metal was no found before and after cleaning by X-ray radiography. Consequently, we confirmed that cleaning of the sand blaster and power nozzle of $CO_2$ snow cleaning were similar to the effect. But, it's very careful to use this method because of high outlet pressure of power nozzle for applying to the iron artifacts. As a result of experiments, it could be found that the cleaning methods should be selected depending on internal state of the artifacts.

The Impact of SSM Market Entry on Changes in Market Shares among Retailing Types (기업형 슈퍼마켓(SSM)의 시장진입이 소매업태간 시장점유율 변화에 미친 영향)

  • Choi, Ji-Ho;Yonn, Min-Suk;Moon, Youn-Hee;Choi, Sung-Ho
    • Journal of Distribution Research
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    • v.17 no.3
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    • pp.115-132
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    • 2012
  • This study empirically examines the impact of SSM market entry on changes in market shares among retailing types. The data is monthly time-series data spanning over the period from January 2000 to December 2010, and the effect of SSM market entry on market shares of retailing types is analyzed by utilizing several key factors such as the number of new SSM monthly entrants, total number of SSMs, the proportion of new SSM entrant that is smaller than $165m^2$ to total new SSM entrants. According to the Korean Standard Industrial Classification codes, the retailing type is classified into 5 groups: department stores, retail sale in other non-specialized large stores(big marts), supermarkets, convenience stores, and retail sale in other non-specialized stores with food or beverages predominating (others). The market shares of retailing types are calculated by the ratio of each retailing type monthly sales to total monthly retailing sales in which total retailing sales is the sum of each retailing type sales. The empirical model controls for the size effects with the number of monthly employees for each retailing type and the macroeconomic effects with M2. The empirical model employed in this study is as follows; $$MS_i=f(NewSSM,\;CumSSM,\;employ_i,\;under165,\;M2)$$ where $MS_i$ is the market share of each retailing type (department stores, big marts), supermarkets, convenience stores, and others), NewSSM is the number of new SSM monthly entrants, CumSSM is total number of SSMs, $employ_i$ is the number of monthly employees for each retailing type, and under165 is the proportion of new SSM entrant that is smaller than $165m^2$ to total new SSM entrants. The correlation among these variables are reported in

    .
    shows the descriptive statistics of the sample. Sales is the total monthly revenue of each retailing type, employees is total number of monthly employees for each retailing type, area is total floor space of each retail type($m^2$), number of store is total number of monthly stores for each retailing type, market share is the ratio of each retailing type monthly sales to total monthly retailing sales in which total retailing sales is the sum of each retailing type sales, new monthly SSMs is total number of new monthly SSM entrants, and M2 is a money supply. The empirical results of the effect of new SSM market entry on changes in market shares among retailing types (department stores, retail sale in other non-specialized large stores, supermarkets, convenience stores, and retail sale in other non-specialized stores with food or beverages predominating) are reported in
    . The dependant variables are the market share of department stores, the market share of big marts, the market share of supermarkets, the market share of convenience stores, and the market share of others. The result shows that the impact of new SSM market entry on changes in market share of retail sale in other non-specialized large stores (big marts) is statistically significant. Total number of monthly SSM stores has a significant effect on market share, but the magnitude and sign of effect is different among retailing types. The increase in the number of SSM stores has a negative effect on the market share of retail sale in other non-specialized large stores(big marts) and convenience stores, but has a positive impact on the market share of department stores, supermarkets, and retail sale in other non-specialized stores with food or beverages predominating (others). This study offers the theoretical and practical implication to these findings and also suggests the direction for the further analysis.

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  • Early Gonadogenesis and Sex Differentiation in the Viviparous Teleost, Ditrema temmincki (태생 경골어류, 망상어(Ditrema temmincki)의 초기생식소 형성 및 성분화)

    • LEE Jung Sick;LEE Young Don
      • Korean Journal of Fisheries and Aquatic Sciences
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      • v.29 no.1
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      • pp.35-43
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      • 1996
    • The appearance of the primordial germ cells (PGC's), early gonadogenesis, sex differentiation and sex ratio of the embryo in the viviparous teleost, Ditrema temmincki were investigated by using photomicroscopy. The PGC's were first observed in the fibrous mesenchymal tissue located between the early alimentary tract and the dorsal body wall in the late embryonic development stage. During the period from the hatching to the individual total length (TL) of 4.0 mm the PGC's were evenly distributed in the fibrous mesenchymal tissue between alimentary tract and body wall. But the period of TL 5.0 mm mesenchymal tissue separated from the dorsal body wall, the PGC's moved to the posterior mesenchymal tissue and formed the primitive gonad. During the early gonadogenesis, differentiation of the testis and ovary were distinguished from the arrangement of the germ cells and somatic cells. Gonad of embryo in TL 10.0 mm can be separated into the ovary and testis by external morphology. The testis had a separated form which was consisted with two lobes, and the ovary had a fused form in half-posterior part. In the testicular differentiation of the embryo, histological pattern of the seminiferous tubule appeared when TL of the embryo was to be 25.0 mm, for the seminal vesicle was formed In the individual TL of 30.0mm. The testis of the embryo with TL of 45.0 mm was similar to that of the adult fish in the external and internal structures. In the ovarian differentiation, formation of the ovigerous folds and the ovarian cavity were clearly observed when the TL reached to 30.0 mm. The ovary from the individual with TL of 60.0 mm was differentiated into a similar ovary as seen in the adult fish in the external and internal structure. Right before parturition the total length of the individual was approximately 63.0 mm of which the individual embryo has an ovary containing the oocytes in the chromatin nucleolus stage, or a testis containing the spermatogonia, respectively. And the embryonic sex ratio of female to male was 1.65 : 1. Ditrema temmincki is dioecism and the pattern of sex differentiation is belonged to a differentiation type.

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    The Study on Geology and Volcanism in Jeju Island (III): Early Lava Effusion Records in Jeju Island on the Basis of $^{40}Ar/^{39}Ar$ Absolute Ages of Lava Samples (제주도의 지질과 화산활동에 관한 연구 (III): $^{40}Ar/^{39}Ar$ 절대연대자료에 근거한 제주도 형성 초기 용암 분출 기록)

    • Koh, Gi-Won;Park, Jun-Beom
      • Economic and Environmental Geology
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      • v.43 no.2
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      • pp.163-176
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      • 2010
    • We report twenty data for early lavas erupted during the initial period of formation of Jeju Island on the basis of review on 539 data of whole-rock greochemistry and $^{40}Ar/^{39}Ar$ age dating out of mainly core samples from 69 boreholes drilled in the lower land since 2001 and 66 outcrop sites. Out of 69 boreholes, the early lava flow units are identified from samples collected from Beophocheon (EL 235 m, 210 m deep), Donnaeko (EL 240 m, 230 deep), Donghong-S (EL 187 m, 340 m deep), 05Donghong (EL. 187.6 m, 340 m deep), Dosoon (EL 305 m, 287 m deep), Sangye (EL 230 m, 260 m deep), Mureung-1 (EL 10.2 m, 160 m deep), and Gapa (EL 17.5 m, 92 m deep), which are located in the southern and southwestern portion of Jeju Island. While, the well-known outcrops from Sanbangsan, Wolrabong, Wonmansa, and Kagsubawi are also reconfirmed. $^{40}Ar/^{39}Ar$ age dating results of these lavas range from 1 Ma to 0.7 Ma, indicating that the data can be useful to constrain on age and geochemical characteristics of early lava effusion period in the formation of Jeju Island. Especially, samples with trachybasalt in composition collected from 143 m to 137 m, and from 135 m to 123 m below ground surface at 05Donghong hole have the oldest ages, $992\pm21$ Ka and $988\pm38$ Ka, respectively. This study suggests that in Jeju Island the first lava with trachybasalt in composition may have effused around 1 Ma ago, and the effusion style and chemical compositions of lavas must have changed to the formation of lava domes with trachyte-trachyandesite-basaltic trachyandesite and the eruption of lavas with alkali basalt and trachybasalt intermittently during the period from 0.9 Ma to 0.7 Ma ago. It also indicates that the initial lava flows below the ground are intercalated with or underlain by the Seoguipo Formation except for several exposed domal structure areas such as Sanbangsan and Kagsubawi, implying that the early lava effusion may have intermittently and sporadically occurred with nearby hydrovolcanism and sedimentation.

    The new explore of the animated content using OculusVR - Focusing on the VR platform and killer content - (오큘러스 VR (Oculus VR)를 이용한 애니메이션 콘텐츠의 새로운 모색 - VR 플랫폼과 킬러콘텐츠를 중심으로 -)

    • Lee, Jong-Han
      • Cartoon and Animation Studies
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      • s.45
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      • pp.197-214
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      • 2016
    • Augmented Reality, virtual reality in recently attracted attention throughout the world. and Mix them mixed reality etc., it has had a significant impact on the overall pop culture beyond the scope of science and technology. The world's leading IT company : Google, Apple, Samsung, Microsoft, Sony, LG is focusing on development of AR, VR technology for the public. The many large and small companies developed VR hardware, VR software, VR content. It does not look that makes a human a human operation in the cognitive experience of certain places or situations or invisible through Specific platforms or program is Encompass a common technique that a realization of the virtual space. In particular, out of the three-dimensional image reveals the limitations of the conventional two-dimensional structure - 180, 360 degree images provided by the subjective and objective symptoms such as vision and sense of time and got participants to select it. VR technology that can significantly induce the commitment and participation is Industry as well as to the general public which leads to the attention of colostrum. It was introduced more than 10 related VR works Year 2015 Sundance Film Festival New Frontier program. The appearance VR content : medical, architecture, shopping, movies, animations. Also, 360 individuals can be produced by the camera / video sharing VR is becoming an interactive tunnel between two possible users. Nevertheless, This confusion of values, moral degeneration and the realization of a virtual space that has been pointed out that the inherent. 4K or HUD, location tracking, motion sensors, processing power, and superior 3D graphics, touch, smell, 4D technology, 3D audio technology - It developed more than ever and possible approaches to reality. Thereafter, This is because the moral degeneration, identity, generational conflict, and escapism concerns. Animation is also seeking costs in this category Reality. Despite the similarities rather it has that image, and may be the reason that the animation is pushed back to the VR content creation. However, it is focused on the game and VR technology and the platform that is entertaining, but also seek new points within the animation staying in the flat Given that eventually consist of visual images is clear that VR sought. Finally, What is the reality created in the virtual space using VR technology could be applied to the animation? So it can be seen that the common interest is research on what methods and means applied.

    Evaluation of Construction Operation and Design Properties of CLSM for Corrugated Pipe in Underground (파형강관을 이용한 지하매설물용 뒤채움재 설계 및 시공성 평가)

    • Lee Kwan-Ho;Park Jae-Heon
      • International Journal of Highway Engineering
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      • v.8 no.2 s.28
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      • pp.63-74
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      • 2006
    • During the construction of circular underground pipe, the non-proper compaction along the pipe and the decrease of compaction efficiency have been the main problems to induce the failure of underground pipe or facility. The use of CLSM (controlled low strength materials) should be one of the possible applications to overcome those problems. In this research, the full-scaled field test and the numeric analysis using PENTAGON-3D FEM program were carried out for three different cases on the change of backfill materials, including the common sand, the soil from construction site, and the CLSM. From the full-scaled test in field, the use of in-situ CLSM as backfill materials reduced the vertical and lateral deformation of the pipe, as well as the deformation of the ground surface. The main reason for reducing the deformation would be the characteristics of the CLSM, especially self-leveling and self-hardening properties. The measured earth pressure at the surround of the corrugated pipe using the CLSM backfills was the smaller than the other cases, and the absolute value was almost zero. Judging from the full-scaled field test and FEM analysis, the use of CLSM as backfill materials should be one of the best choices reducing the failure of the underground pipes.

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    Long-Term Observation of Temperature in the Coastal Waters Adjacent to the Wolsung Nuclear Power Plant (월성 원자력 발전소 주변 해역의 장기간 수온관측)

    • Chung, Jong-Yul;Kang, Hyoun-Woo;Shin, Young-Jae;Kim, Kye-Young;Jun, Ho-Kyung
      • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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      • v.3 no.4
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      • pp.183-192
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      • 1998
    • The long-term observation of temperature in the coastal waters adjacent to the Wolsung Nuclear Power Plant has been carried out from November 10, 1996 to August 22, 1997, for approximately 280 days using a real-time temperature measurement buoy system. The sea-surface temperature was measured at every 10 minute using 10 buoys. The vertical structure of temperature was investigated near the outlet of the plant with two thermistor chains equipped with 10 sensors at 1 m interval The monthly averaged temperature was the lowest with spatial average of $12.8^{\circ}C$ in February and was the highest in August with spatial average of $19.6^{\circ}C$. The extremely low temperature was frequently observed between June and August, which seems to be the consequence of the intrusion of cold water near the southeastern coast of Korea. Distributions of the daily and hourly averaged temperature show that the highest temperature always occurred near the outlet of the plant and the warm-water patch moved along the north-south direction with the semidiurnal period. The semidiurnal fluctuation of temperature was also observed near the surface of the vertical profiles. The spectral analysis of temperature between February and April 1997 shows that the semidiurnal components prevailed near the outlet. It is likely that the semidiurnal components were due to the prevailing semidiurnal tide in this region. In August 1997, the diurnal components were dominant at the surface water of all stations except Station 12, which suggests that the warm water from the outlet of the plant has less effects in summer on the surrounding waters than the strong solar radiation.

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    Application of the Pulsatile Cardiopulmonary Bypass in Animal Model (이중 박동성 인공심폐기의 동물 실험)

    • Shin, Hwa-Kyun;Won, Yong-Soon;Lee, Jea-Yook;Her, Keun;Yeum, Yook;Kim, Seung-Chul;Min, Byoung-Goo
      • Journal of Chest Surgery
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      • v.37 no.1
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      • pp.1-10
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      • 2004
    • Background: Currently, the cardiopulmonary machine with non-pulsatile pumps, which are low in internal circuit pressure and cause little damage to blood cells, is widely used. However, a great number of experimental studies shows that pulsatile perfusions are more useful than non-pulsatile counterparts in many areas, such as homodynamic, metabolism, organ functions, and micro-circulation. Yet, many concerns relating to pulsatile cardiopulmonary machines, such as high internal circuit pressure and blood cell damage, have long hindered the development of pulsatile cardiopulmonary machines. Against this backdrop, this study focuses on the safety and effectiveness of the pulsatile cardiopulmonary machines developed by a domestic research lab. Material and Method: The dual-pulsatile cardiopulmonary bypass experiment with total extracorporeal circulation was conducted on six calves, Extracorporeal circulation was provided between superior/inferior vena cava and aorta. The membrane oxygenator, which was placed between the left and right pumps, was used for blood oxygenation. Circulation took four hours. Arterial blood gas analysis and blood tests were also conducted. Plasma hemoglobin levels were calculated, while pulse pressure and internal circuit pressure were carefully observed. Measurement was taken five times; once before the operation of the cardiopulmonary bypass, and after its operation it was taken every hour for four hours. Result: Through the arterial blood gas analysis, PCO2 and pH remained within normal levels. PO2 in arterial blood showed enough oxygenation of over 100 mmHg. The level of plasma hemoglobin, which had total cardiopulmonary circulation, steadily increased to 15.87 $\pm$ 5.63 after four hours passed, but remained below 20 mg/㎗. There was no obvious abnormal findings in blood test. Systolic blood pressure which was at 97.5$\pm$5.7 mmHg during the pre-circulation contraction period, was maintained over 100 mmHg as time passed. Moreover, diastolic blood pressure was 72.2 $\pm$ 7.7 mmHg during the expansion period and well kept at the appropriate level with time passing by. Average blood pressure which was 83$\pm$9.2 mmHg before circulation, increased as time passed, while pump flow was maintained over 3.3 L/min. Blood pressure fluctuation during total extracorporeal circulation showed a similar level of arterial blood pressure of pre-circulation heart. Conclusion: In the experiment mentioned above, pulsatile cardiopulmonary machines using the doual-pulsatile structure provided effective pulsatile blood flow with little damage in blood cells, showing excellence in the aspects of hematology and hemodynamic. Therefore, it is expected that the pulsatile cardiopulmonary machine, if it becomes a standard cardiopulmonary machine in all heart operations, will provide stable blood flow to end-organs.

    Chemical Structures of Lignin by Infrared Spectroscopy - Assignment of Infrared Absorption Bands in Lignin Compounds - (IR Spectra에 의(依)한 리그닌의 화학구조(化學構造) - 단(單), 삼량체(三量體) 리그닌화합물(化合物)의 흡수대귀속(吸收帶歸屬) -)

    • Hwang, Byung-Ho
      • Journal of the Korean Wood Science and Technology
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      • v.11 no.3
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      • pp.58-69
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      • 1983
    • This research is performed to compare lignin compounds isolated in Pinus koraiensis Sieb et Zucco, with those compounds which have been already isolated. and to elucidate IR spectra of functional groups and aromatic nucleus for chemical structure of lignin. In vanillin and dehydrodivanillin having carbonyl group ill ${\alpha}$-position. characteristic absorption band of carbonyl group was confirmed in 1665 $cm^{-1}$. Absorption band of vanillic and syringic acid with carboxyl group were indicated in 1675 and 1690 $cm^{-1}$ respectively. Syringic acid showed low wave number because this was affected by methoxyl group. Characteristic absorption bands of guaiacyl, syringly and guaiacyl-syringyl co-polymer nucleus were clearly disclosed in diarylpropane compounds. It were reconfirmed that absorption band of guaiacyl showed longer wave number than of syringly nucleus.

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    Distribution Status and Phylogenetic Relationship of Myotis aurascens in Jeju Island (제주도에서 대륙쇠큰수염박쥐(Myotis aurascens)의 분포 현황 및 계통 유연관계)

    • Kim, Yoo-Kyung;Park, Su-Gon;Kim, Tae-Wook;Park, Jun-Ho;Adhikari, Pradeep;Kim, Ga-Ram;Park, Seon-Mi;Lee, Jun-Won;Han, Sang-Hyun;Oh, Hong-Shik
      • Journal of Life Science
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      • v.25 no.12
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      • pp.1354-1361
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      • 2015
    • This study was aimed to investigate the distribution status and phylogenetic relationship of Myotis aurascens in Jeju Ialnd, which has not clearly confirmed until now. We found three groups of M. aurascens from three different cave enforcements (CEs). The bat population of Jeju Island had smaller levels of HBL and Hfcu, but greater levels of TL, EL, FAL, and Tra than those of the Korean Peninsula population. Jeju bats had wide range in the lengths of FAL and Hfcu comparing to those of European bats. From the bimonthly monitoring to each finding site, we have actually failed to observe those again, estimating that they use those CEs as the daily-roosting place in activating seasons. The sequences of CYTB and COI genes showed identical sequences among Jeju bats tested, indicating that they are maternally related. The results from molecular phylogeny showed that the sequences of these bats located on the same branch with those for M. aurascens in the phylogenetic trees. Besides, the nucleotide sequences of the Jeju bats showed the closest relation with that of Korean Peninsula. Consequently, these findings indicate that the bats of M. aurascens, verified the natural distribution in Jeju Island, have originated from a single maternal origin and differences in morphological and genetic backgrounds form those of Korean Peninsula and the other countries, and had probably immigrated via Korean Peninsula. These findings will contribute as basic information for understanding the migration history and biogeographic relationship of mammals on Jeju Island in East Asia.


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