• Journal of the korean Society of Automotive Engineers
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• v.4 no.2
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• pp.58-68
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• 1982

It is well known to diesel engineers that the heat release pattern is one of the most important factors affecting engine performance. Thorough research in heat release pattern has materially helped the progress in high-speed diesel engine development . This paper is based on the research conducted at KAIST and Daewoo Heavy Industry last year. The purpose of this paper is to determine the heat release pattern in combustion chamber of MAN M type, the famous low-noise engine. Thermodynamic cycle simulation was performed using Whitehous-Way's heat release pattern with modified coefficients and Annand's heat transfer model. Instantaneous temperature and pressure of gas in cylinder could be determined by the numerical solution of simultaneous equation of mass conservation, equation of energy conservation, and state equation of ideal gas. Calculated results were compared with measured values in some details emphasizing upon the factors affecting rate of heat release. The agreement was fairly good and revealed why M type should have lower burning velocity at the early part of combustion in spite of high injection rate. Additional results by parametric studies were given in relation to fuel injection conditions for further application to engine development.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.6
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• pp.80-91
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• 2005

This research aims to classify wetland types and evaluate functions of a dam lake. The case study area is Boryung lake in Boryung City. In this study was carried out based upon field surveys, drawing maps and publication, and modified-RAM which can evaluate the general functions and conservation values of wetlands. Eight functions of 2-12 variables each are analyzed for assessing the wetland functions. The analysis shows that several types of wetlands were identified, such as Palustrine/ Perennial/ Hydrophytes, Palustrine/ Perennial/ Openwater, Palustrine/ Seasonal/ Herbal, Palustrine/ Seasonal/ Shrub and Scrub, Palustrine/ Seasonal/ Hydrophye, and Riparian/ Seasonal/ Shrub in the Boryung lake. The average level of functions of the wetlands is very "HIGH", and it is recommended that prompt conservation measures should be taken.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.11
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• pp.1079-1088
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• 2001

A dynamic simulation model was developed to analyse the transient characteristics of a multi-inverter heat pump. The programs included a basic air conditioning system such as a evaporator, condenser, compressor, linear electronic expansion valve (LEV) and by-pass circuit. The theoretical model was derived from mass conservation and energy conservation equations to predict the performance of the multi-inverter heat pump at various operating conditions. Calculated results were compared with the values obtained from the experiments at different operation frequencies of compressor, area of the LEV and configuration of indoor units operation. The results of the simulation model showed a good agreement with the experimental ones, so that the model could be used as an efficient tool for thermodynamic design and control factor design of air-conditioners.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3618-3623
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• 2011

This paper presents a stable isotope chemistry of bone collagen and carbonate. Bone carbonate has the potential to provide additional isotopic information. However, it remains controversial as to whether archaeological bone carbonate retains its original biogenic signature. I used a novel application of bone density fractionation and checked the integrity of ${\delta}^{13}C_{apa}$ values using radiocarbon dating. Diagenesis in archaeological bone carbonate still remains to be resolved in extracting biogenic information. The combined use of bone density fractionation and differential dissolution method shows a large shift in the ${\delta}^{13}C_{apa}$ values. Although ${\delta}^{13}C_{apa}$ values are improved in lighter density fractions, a large percentage of contamination in bone carbonate was reported via $^{14}C$ dating compared to that noted with bone collagen.

• Journal of The Geomorphological Association of Korea
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• v.25 no.4
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• pp.117-129
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• 2018

Dongmag beach area contains diverse geological and geomorphological outcrops which can be used for geotourism purposes. They are as follows; headland with granodiorite with plenty of enclaves and sandy beach, which is fed from Manisan with well-developed sheeting joints composed of granite and granodiorite. Weathered material from the hillside feedsthe one and only sandy beach in Ganghwado Island. Weathered outcrop at the hillside behind beach exposes typical spherical weathering also. Bunori Dondae Fort which was built on top of sea cliff with granodiorite has plenty of history and cultural values commands an extraordinary view of tidal flats and coastal landforms. This geosite with high geodiversity can be used for interpreters who provide balanced views of nature conservation.

• Journal of Conservation Science
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• v.26 no.1
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• pp.69-76
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• 2010

As the tangible evidence, documentary art records are permanent records to reflect the historical, symbolical, cultural and artistic value. Also, documentary art records are related with mission fulfillment of public institution and it is documentary with administrative, cultural and artistic values as the works of documentary production and application of the administrative image. "The public records management law" was the first time that administration documents were incorporated and in the act No. 3 of administrative records management, the preservation and management system of documentary art records became legislated. The management of documentary art records are difficult to categorize only by the reflect of characteristics or materials. Because documentary art records are collected in many ways and made with materials. It needs to be collected with many informations on basic materials and with the appropriate conservation and management category. Documentary art records do not have lots of demands but the level of consciousness is improving and the possibility of opening to public is increasing for improvement with the right to know. In near future, the documentary art records will be used for the interpretation of historical and cultural preservation and modern cultural heritage could have the value as it is expected. Primarily to prevent deterioration on documentary art records the standard survey card should be made to categorize the damage rate and to check the status on each documentary art records. In addition, establishing a systematic management plan for various documentary art records are needed with the training of professionals for the conservation of documentary art records.

• Journal of Conservation Science
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• v.25 no.4
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• pp.431-438
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• 2009

We have investigated the suitable measuring method and condition on the hardness testing for the earthenwares excavated from Poongnap mud castle in Hanseong Baekje period. The earthenwares which used on hardness testing have been classified according to Mohs hardness and external form and color. The Ultrasonic and Equotip testing method have used to the hardness testing on the surface of the earthenwares and the Rockwell and Micro-vickers testing methods have used to the hardness testing on the cross section of the earthenwares. As the results, the two methods applied to the surface of the earthenwares were very hard on the precise measurement and the measuring values were incompatible with the tendency classified according to Mohs hardness and external form and color. On the testing for the cross section of earthenware, the Rockwell-superficial hardness testing method was more suitable for the soft texture earthenware and highest reproducibility of the measuring value obtained at the test load and indentor are 15kgf and 1/16 “iron ball, respectively. The Micro-Vickers hardness testing method was suitable for the hard texture earthenware and highest reproducibility and accuracy of the measuring value obtained at the test load is 100gf. This results show strong possibility of progress on the classifying and comparing study for hardness of the earthenware and therefore active studies are expected on the field.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.195-202
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• 2012

Three-season field study was conducted to investigate the distribution of monoterpene(10) and air anion in ambient air at five forests. ${\alpha}$-Pinene, camphene, sabinene, ${\beta}$-pinene, myrcene, terpinolene, limonene, 1,8-cineol, linalool, and camphor were quantified in the samples collected. The highest 4-hour mean concentration of total monoterpene were ${\beta}$-pinene+myrcene as 958 pptv at Juknokwon dominated by bamboo and ${\alpha}$-pinene (524 pptv), limonene (445 pptv) at Wood Land and Suncheon Bay, respectively. The seasonal means were observed to peak during spring with their maximum at Wood Land and Seonam Temple and during summer at Juknokwon and Suncheon Bay. The 24 hour concentration mean of atmosphere standards were found with much lower values than those by law. The highest concentrations of air anion were measured $400{\sim}3,000ea{\cdot}mL^{-1}$ through the sites. There is no significant correlation between the concentration of monoterpene and air anion.

• Journal of Conservation Science
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• v.29 no.2
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• pp.127-138
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• 2013

Plastic, widely used as a material for contemporary art, get damaged as directly exposed to temperature, humidity, ultra violet, etc. And it is very quickly damaged in early time, once damaged, it can't recover into original state. But like this characteristics, there is a few advanced research in Korea. So this study deal with a rising value of plastic artifacts in other country, United Kingdom and France, current conservation state, identification and cleaning method. Also 5 types of cleaners(distilled water, ethanol, acetone, eraser) and adhesives(cyanoacrylate, epoxy, acrylic, chloroprene rubber) were evaluated by produced plastics(PVC, PE, PP, PS, PU). As a result of experiment, ethanol and acetone that were previous evaluated in other research performed in other country are the best cleaner. Result of degradation after adhesive, cyanoacrylate and epoxy resin showed better performance and stability. As a basic research, this study is expected that can be used in future researches.

• Journal of Conservation Science
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• v.26 no.2
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• pp.121-132
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• 2010

The Bukjiri Maaeyeoraejwasang (National Treasure No. 201) consists of two-mica granite in medium size, which was the simbol of power in the region of the Silla period. Magnetic susceptibility of the host rock was measured as 0.41(${\times}10^{-3}$ SI unit), which has the similar range with surrounding outcrop. The Buddha developed parallel discontinuous plane of NE to SW strike and damaged seriously by exfoliation, granular disintegration and brown discoloration as 41.5%, 16.7% and 40.0%, respectively. As a result of the ultrasonic velocity, which was relatively weak values as 1,629m/s (Buddha area) and 1,549m/s (surrounding outcrop), improved about 900m/s compared to last treatment. From the results of the evaluation for slope stability, identified the possibility of toppling failure in the Buddha, and planar and wedge failure in host rock. Therefore, we suggest for the safely conservation of the Buddha, continuance monitoring for understand behavior of discontinuity system of the surface, and necessitate foundation reinforcement method for the rock which has the danger of collapse.