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Determination of PEG Concentration and Solvent Selection for Freeze-Drying of Highly-Degraded Waterlogged Woods (고함수율 수침고목재의 동결 건조를 위한 PEG 전처리 농도 및 용매 설정)

  • Kim, Soo-Choul;Park, Won-Kyu;Yi, Yong-Hee
    • Journal of Conservation Science
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    • v.9 no.1
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    • pp.40-47
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    • 2000
  • Dimension stability was examined after PEG pretreatment and post freeze-drying treatment in order to determine the PEG(#3350) concentration and solvent for pre-treatment of freeze-drying of highly-degraded waterlogged ash woods(Fraxinus spp.; ca. 5,700 BP) excavated from peat lands at Pyungtack, Kyounggi-do. At the low concentration (<30-40%) of PEG soaking in both water and t-butanol, the weight increases abruptly, but at high concentration (>50%) gradually, consequently, taking longer treatment time. PEG loading was higher in t-butanol solution than in water. However, the best dimesional stability was obtained from freeze-drying after lower PEG solution (40% in water) soaking. Low dimensional stability, found in the samples treated with higher PEG solutions (60%-70% in t-butanol), might come from incomplete freezing and excess PEG absorbing moisture. The samples air-dried after 70% PEG treatment had collapse defects. In conclusion, the use of low concentration (about 40% in water) PEG solution was the most suitable pretreatment for freeze drying of highly-degraded waterlogged ash woods.

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A 2-D Location Determination Model of Buried Persons in Collapsed Shape using Optimal Wireless Communication Technology (최적 무선통신 기술을 활용한 붕괴지형 매몰자의 2차원 매몰위치 결정 모델)

  • Moon, Hyoun-Seok;Lee, Woo-Sik;Lee, Gun-Woo;Han, Dong-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.12
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    • pp.8879-8888
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    • 2015
  • When the disaster like earthquake in urban area occur, due to the collapse accidents for subway, tunnel space with buildings or underground area, enormous property and human damage are happened. Specially, since it is difficult to identify survived status of humans within collapsed debris and accurately buried locations of the humans, inputs of considerable time and manpower for rescuing them are required. Besides, secondary damage can be occurred by additional collapses. The aim of this study is to propose a stochastic location positioning method that enables to provide aid information by determining locations of mobile devices for buried persons in 2-D plane using wireless communication technologies. This study selected a detection method for buried persons based on Wi-Fi signal, and identified characteristics of signal strengths by distance unit. Using these methods, a stochastic location detection model in 2-D plane was built. It is expected that this technology will be utilized as a core technology that can protects safety and human life of the public by providing data for rescuing quickly buried persons in cases of national disasters for future.

A Study on the Properties of fusion Design -Especially on the Change of Cultural Environment- (퓨전디자인의 속성에 관한 연구 - 문화환경의 변화를 중심으로 -)

  • 박규현;김윤경
    • Archives of design research
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    • v.13 no.3
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    • pp.211-220
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    • 2000
  • Cultural contact, which means a current that an influential culture diffuses to another, represents the penetration of the one to the other in a negative respect and'mixture'or 'fusion'of them in an affirmative respect. Fusion of cultures was not easy to take place in the past when nationalism and ultranationalism suppressed it ideologically, inconvenient transportation and communications were obstacles to it, and most of countries were under the influences of folk religions. Today, however, mutually heterogeneous cultures can be shared by a lot of things such as collapse of a view of nation resulted from globalization, breakdown of regional characteristics, abolition of trade barriers, freedom of communications and realtime information network. Those have rendered fusion possible. Fusion in this modern consuming society is extending much faster and more extensively than at any time in the past. In addition, more and more cultural elements seem to collide and compromise with one another in the name of fusion, not relaxing the bridle of fusion, from the present situations that preference in consumption becomes subdivided and a variety of individuality is strongly attempted to seek for, This study is on the subject of the properties of'Fusion', one of new styles in a mass culture, especially focused on sociologic cultural phenomena. Furthermore, it is expected to look for a fusion in interior design which expresses sociologic cultural phenomena most in a field of design, to examine it theoretically, and to prospect a future trend of fusion design based on investigation of the latest prevailing trend.

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Study on Suggestion a Standard Installation for Damage Reduction alarm System using Cut-Slope Data (국내 도로절개면 현황 및 붕괴 분석을 통한 경보시스템 설치 기준에 관한 기초적 연구)

  • Bae, Gyu-Jin;Koo, Ho-Bon;Baek, Yong
    • The Journal of Engineering Geology
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    • v.12 no.1
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    • pp.53-61
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    • 2002
  • Cut-slope due to the road construction is one of the most significant problems in the domestic case, that is, 70% of the land is covered by mountain. Moreover, typhoons or heavy rains concentrated in summer season causes the failure of cut-slope. Rock-fall and soil slope failure take 40.8% and 29.5% out of the entire domestic cut-slope failure, respectively. Rock-fall is quickly occurred by the free fall or rolling of rock fragments generally in the upper slope. Soil slope failure produces a clastics-flow and increases casualty especially when caused by heave rainfall because the velocity of the movement is verb high. Considering the car speed and rock-fall velocity, it will take a life in a moment. This study analyzes a set of field data of most recently collapsed domestic road cut-slopes to characterize these cut-slopes and the nature of rock-falls and clastics flows at each site. Based on the results, design criteria for a road alarm system are proposed, considering the relationship between the time required for clastics-flow and the velocity and braking distance of a cat at the incidence. The road alarm system proposed herein would operate instantly after a rock-fall and it will minimize damages, by warning drivels approaching to the collapse or collapsing location in advance.

Evaluation of Erosion Resistance Capability with Adhesive Soil Seeding Media (접착성 식생기반재의 침식저항능력 평가)

  • Seong, Si-Yung;Shin, Eun-Cheol
    • Journal of the Korean Geosynthetics Society
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    • v.14 no.2
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    • pp.71-79
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    • 2015
  • This paper describes vegetation based soil-media hydroseeding measures that have been previously applied as slope revegetation methods show problems such as insufficient binding force, drying, and insufficient organic matter. In particular, in the case of slope faces in regions where scattering is severe, a vicious circle exists in which remarkably low vegetation cover rates and increases in withering rates over time lead to further decreases in vegetation cover rates, which lead to further increases in erosion and scattering. Therefore, in the present study, environment friendly soil stabilizers were applied for resistance against erosion or scattering and engineering evaluations such as long-term immersion tests and flow resistance tests were conducted to determine appropriate mixing ratios. According to the results of long-term immersion tests utilizing environment friendly soil stabilizers and existing greening soil based materials, 100% collapse occurred at 30 hours and 40 days in the case of soil stabilizer mixing ratios of 0% and 2%, respectively. While the original form of the samples remained intact until the experiment was completed in the case of mixing ratios exceeding 4% indicating that 2% or higher soil stabilizer mixing ratios could affect the maintenance of forms even under extreme conditions. In addition, artificial rainfall tests were conducted on 40, 45, and 55 degree slope faces to evaluate the structural stability of vegetation based materials. Flow resistance tests were conducted on soil stabilizer mixing ratios of 0, 4, 8% to evaluate erosion resistance capability. Based on the results of the tests, environment friendly soil stabilizers applied for prevention of scattering or resistance against erosion by rainwater are considered to provide large effects to reduce losses and loss rates showed a tendency of decreasing rapidly when soil stabilizers were mixed.

Nutritive and Antioxidative Properties of Eggplant by Cooking Conditions (조리조건에 따른 가지(Solanum melongena L.)의 영양 및 항산화 특성 연구)

  • Ko, Hyun-Jung;Sun, Tian Yu;Han, Jung-Ah
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.12
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    • pp.1747-1754
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    • 2016
  • The nutritive and antioxidative properties of eggplant by cooking conditions based on hardness range were evaluated. Three cooking methods (boiling, microwaving, and steaming) with three different times were used, and cooked eggplant was freeze-dried for analysis. For color of peel, fading was most observed during boiling and least during steaming. Although raw eggplant showed high free radical scavenging activity based on 1,1-diphenyl-2-picrylhydrazyl and total polyphenol contents, both were further increased upon steaming but significantly decreased upon boiling. The amount of chlorogenic acid in eggplant increased upon steaming and decreased upon boiling or microwaving. Notable cell wall collapse was observed in the microwaved sample compared to the other two cooking methods. Calcium elution from tissues or the cell wall was observed in all samples, and the amount significantly increased with cooking time, especially by steaming.

Effect of Presteaming on the Drying Rate and Drying Defects of Quercus acutissima (증기전처리(蒸氣前處理)가 상수리나무판재(版材)의 건조속도(乾燥速度)와 건조결함(乾燥缺陷)에 미치는 영향(影響))

  • Lee, Hyoung-Woo;Jung, Hee-Suk
    • Journal of the Korean Wood Science and Technology
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    • v.13 no.2
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    • pp.3-13
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    • 1985
  • This study was carried out to investigate the effects of presteaming on the drying rate and drying defects of 3 cm - thick Quercus acutissima. Specimens for presteaming were steamed green at $100^{\circ}C$ for 4 hours and then kiln-dried to 10 percent moisture, content with controls, using the kiln-drying schedule ($T_4-C_2$) recommended by Rasmussen. The results obtained were as follows: 1. Presteaming reduced drying time approximately 18 percent from 70 to 10 percent moisture content. 2. The effect of presteaming on surface checking was not significant. 3. Presteamed specimens showed the reduction in end checking compared with controls. 4. Percents of boards with collapse, cupping, and honeycomb of presteamed specimens were slightly lower than those of controls. 5. Dry lumber grade of presteamed specimens was better than that of controls. Percent of first grade boards of presteamed specimens was 20 percent higher than that of controls and percents of second and third grade boards of presteamed specimens were 15 and 5 percent lower than those of controls, respectively.

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Performance Evaluation of LTE-VPN based Disaster Investigation System for Sharing Disaster Field Information (재난사고 정보공유를 위한 LTE-VPN기반 현장조사시스템 성능평가)

  • Kim, Seong Sam;Shin, Dong Yoon;Nho, Hyun Ju
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.11
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    • pp.602-609
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    • 2020
  • In the event of a large-scale disaster such as an earthquake, typhoon, landslide, and building collapse, the disaster situation awareness and timely disaster information sharing play a key role in the disaster response and decision-making stages for disaster management, such as disaster site control and evacuation of residents. In this paper, an exited field investigation system of NDMI (National Disaster Management Research Institute) was enhanced with an LTE-VPN- based wireless communication system to provide an effective on-site response in an urgent disaster situation and share observation data or analysis information acquired at the disaster fields in real-time. The required performance of wireless communication for the disaster field investigation system was then analyzed and evaluated. The experimental result for field data transmission performance of an advanced wireless communication investigation system showed that the UDP transmission performance of at least 4.1Mbps is required to ensure a seamless video conference system between disaster sites. In addition, a wireless communication bandwidth of approximately 10 Mbps should be guaranteed to smoothly share the communication and field data between the survey equipment currently mounted on the survey vehicle.

Video-Assisted Thoracic Surgery Under Epidural Anesthesia -in High-Risk Group (경막외마취하에 비디오 흉강경수술 - 고위험군에서)

  • Lee, Song-Am;Kim, Kwang-Taik;Kim, Il-Hyeon;Park, Sung-Min;Baek, Man-Jong;Sun, Kyung;Kim, Hyoung-Mook;Lee, In-Sung
    • Journal of Chest Surgery
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    • v.32 no.8
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    • pp.732-738
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    • 1999
  • Background: Video-assisted thoracoscopic surgery has become a standard therapy for several diseases such as pneumothorax, hyperhidrosis, mediastinal mass, and so on. These methods usually required single-lung ventilation with double-lumen endobronchial tube to collapse the lung under general anesthesia. However, risks of general anesthesia itself and single-lung ventilation must be considered in high-risk patients. Material and method: Between December 1997 and July 1998, eight high-risk patients (6: empyema, 1: intractable pleural effusion, 1: idiopathic pulmonary fibrosis) with underlying pulmonary disease and poor general condition were treated by video-assisted thoracoscopic surgerys under epidural anesthesia and spontaneous breathing. Result: Video-assisted thoracoscopic surgerys were successfully per formed in 7 patients. Conversion to general anesthesia was required in 1 patient because of decrease in spontaneous breathing. But, conversion to open decortication was not required. In two patients with chronic empyema, one patient required thoracoplasty as a second procedure and one patient required re-video-assisted thoracoscopic procedure due to a recurrence. The mean operative time was 31.8$\pm$15.2 minutes. No significant postoperative respiratory com plication was encountered. Conclusion: Video-assisted thoracoscopic surgerys can be per formed safely under epidural anesthesia for the treatment of empyema and diagnosis of pulmonary abnormalities in high-risk patients.

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Formation of Efflorescence and Dissolving Experiments for Removing Control on the Stone Pagoda of the Mireuksaji Temple Site, Iksan, Korea (익산 미륵사지 석탑의 백화현상과 제어를 위한 용출실험)

  • Lee, Dong-Sik;Lee, Chan-Hee;Kim, Sa-Dug
    • Journal of Conservation Science
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    • v.19
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    • pp.5-18
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    • 2006
  • The Mireuksaji stone pagoda of the Iksan was built in Muwang King of Baekjae Kingdom and has maintained its present status through several rebuilding process. Recently, the structural unbalance of the pagoda has worsened, so for scientific maintenance recovery of its original pagoda form, the pagoda is under dismantling process. The original form of this pagoda is being presumed to be a plane square pagoda of nine stories, though only a portion of six stories remains until today. The destroyed part from collapse was liked in insecure pagoda form by Japanese in year of 1915. On the surface of the stone which has gone through the present time, efflorescence appeared as precipitation substance over crusted and due to this phenomenon, the structure and color of thee original stone haven't been preserved. Therefore, quantitative analysis on its kind, emitted status and contamination type of secondary inorganic contamination substance of the over crusted surface were analyzed. Also through reaction experiments, contamination type was defined and tests have been applied to find the requirements that will wash out the contaminants. The result of this study will provide the base of quantitative analysis on the kind of inorganic contamination of the surface of stone assets, and it shall also contribute to the application of scientific maintenance recovery of surface cleaner for efflorescence.

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