• Journal of the Korean GEO-environmental Society
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• v.20 no.2
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• pp.41-48
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• 2019

Soil compaction is one of the most important activities in the area of civil works, including road construction, airport construction, port construction and backfilling construction of structures. Soil compaction, particularly in road construction, can be categorized into subgrade compaction and roadbed compaction, and is significant work that when done poorly can serve as a factor causing poor construction due to a lack of compaction. Currently, there are many different types of compaction tests, and the plate bearing test and the unit weight of soil test based on the sand cone method are commonly used to measure the degree of compaction, but many other methods are under development as it is difficult to secure economic efficiency. For the purpose of this research, a portable penetration meter called the Free-Fall Penetration Test (FFPT) was developed and manufactured. In this study, a homogeneous sample was obtained from the construction site and soil was classified through a sieve analysis test in order to perform grain size analysis and a specific gravity test for an indoor test. The principle of FFPT is that the penetration needle installed at the tip of an object put into free fall using gravity is used to measure the depth of penetration into the road surface after subgrade or roadbed compaction has been completed; the degree of compaction is obtained through the unit weight of soil test according to the sand cone method and the relationship between the degree of compaction and the depth of the penetration needle is verified. The maximum allowable grain size of soil is 2.36 mm. For $A_1$ compaction, a trend line was developed using the result of the test performed from a drop height of 10 cm, and coefficient of determination of the trend line was $R^2=0.8677$, while for $D_2$ compaction, coefficient of determination of the trend line was $R^2=0.9815$ when testing at a drop height of 20 cm. Free fall test was carried out with the drop height adjusted from 10 cm to 50 cm at increments of 10 cm. This study intends to compare and analyze the correlation between the degree of compaction obtained from the unit weight of soil test based on the sand cone method and the depth of penetration of the penetration needle obtained from the FFPT meter. As such, it is expected that a portable penetration tester will make it easy to test the degree of compaction at many construction sites, and will lead to a reduction in time, equipment, and manpower which are the disadvantages of the current degree of compaction test, ultimately contributing to accurate and simple measurements of the degree of compaction as well as greater economic feasibility.

• Journal of the Korean Society of Radiology
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• v.12 no.7
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• pp.895-908
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• 2018

As modern science is developed and advanced, examination and number of times using radiation are increasing daily. General diagnostic X-ray generator is installed on stationary form, But X-ray generator was developed because patient who is in the intensive care unit, operation room, emergency room can not move to general x-ray room. What we examine patient by x-ray generator is certainly necessary, So patient exposure is inevitable. but reducing radiation exposure is highly important matter about radiation technology, guardian, patient in the same hospital room, nurse etc. For this reason, rule regarding safety control of diagnostic x-ray generator revised for radiation worker, patient and protector proclaim that mobile diagnostic x-ray shield must placed in case of examine different location excluding operation room, emergency room, intensive care unit. But, radiogical technologist is having a lot of difficulties to examine with mobile x-ray generator, diagnostic x-ray shield partition, image plate and lead apron. So, when we use x-ray generator, we manufacture shield tools can be attached to the mobile x-ray generator On behalf of x-ray shield partition and conduct analysis and in comparison to part of body and distribution of dose rate and find way to reduce radiation exposure through distribution of dose rate of patient within the radiogical technologist, medical team. Mobile x-ray generator aimed at SHIMADZU inc. R-20, We manufactured equipment for shielding x-ray scattered x-ray by installing shielding wall from side to side based on support beam on the mobile x-ray generator. Shielding wall when moving can be folded and designed to expand when examine. Experiment measured five times in each by an angle for dose rate of eyes, thyroid, breast, abdomen and gonad on exposure condition of upper and lower extremity, chest, abdomen which is examined many times by mobile x-ray generator. We used dosimeter RSM-100 made by IJRAD and measured a horizontal dose rate by body part. The result of an experiment, shielding decreasing rate of the front and the rear showed 77 ~ 98.7%. Therefore using self-production shielding wall reduce scattered x-ray occurrence rate and confirm can decrease exposure dose consequently. Therefore, through this study, reduction result which is used shielding wall of self-production will be a role of shielding optimization and it could be answer about reduction of medical exposure recommended by ICRP 103.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.1
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• pp.47-58
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• 2019

This paper is brought to analyze an impact of coaching activities over entrepreneur with respect to entrepreneurs' personal characteristics on the performance of Startups focusing on entrepreneur's awareness conversion effect. In particular, the situation of falling focus of serious startup failure on uncoachable obstinate entrepreneur among the several causes of startup failures, this paper define the research mission of reducing this risk by inducing coaching types of cooperations between senior entrepreneur having serial successful startup experiences and beginning entrepreneur. This paper carry out literature reviews chiefly on startup coaching researches rather than mentoring studies because coaching stressing on self-oriented problem defining and solving by entrepreneur actively tend to be more effective than mentoring relying on mentor's guideline passively as solving startup's main upcoming problems. This paper implement four related researches. First, the impact analysis of entrepreneur's personal characteristics on coaching activities, second, influences of entrepreneurs environmental factors on them, Third, impact of coaching activities on entrepreneur's awareness conversion effect, Fourth, how strongly this conversion effect contributing on the performance of startup. As results of empirical research, first, this paper prove that entrepreneur's environmental factors impact positively on coaching activities over entrepreneur although failing on validating on significant impact of entrepreneur's personal characteristics on coaching activities. Second, this paper prove that coaching activities positively influence on entrepreneur's awareness conversion, hence ultimately positively on the performance of startups. As conclusion, this paper validate that coaching activities over entrepreneur through inducing on the conversion of entrepreneur's awareness lead entrepreneur to setting the bar high and accountable planning of business milestone. This paper contribute on delivering policy implication that government initiatin action-oriented training program for entrepreneurs should accept the module of coaching session to produce more effective results.

• The Korean Journal of Archival Studies
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• no.19
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• pp.3-55
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• 2009

Records of architectural cultural properties, in case of accidents, show who are to blame, present what evidences are to establish the cause, and also are used for checking if there were any problem in policies and regulations in preserving and caring architectural cultural properties. These records are of great importance in their roles and are of essential use regardless of time and space. Considering its significance, In that architectural cultural properties requires setting clear goals and directions and as well, criteria, for management, we need methods of systematical control and consideration for its characteristics. This research started with the sense of purpose that managing architectural cultural properties are in need of systematic and concrete control, based on the perception that they need protecting and transmitting. The goal of this thesis is to work on the current archiving status of architectural cultural properties by monitoring patterns and processes in archival administration, to diagnose problems by looking into the records creation and management, and to present the improvement plan which would lead to the architectural cultural properties' more efficient management and better use in the future. The management of architectural cultural properties begins with registering and assigning. Cultural Heritage Administration is in charge of control, supervision, and budget and local governments deal with direct management. Accordingly, records are by the hands of each local governmental body. Currently, each cultural property has its management depending on every different working environment in each governmental body. Architectural cultural properties needs managing in one body through the synthetic and unified, concrete and systematic manual and guide for management. Archiving architectural cultural properties have need of unitive management through a professional system, considering the physical characteristics and history of archiving. Unified management system will enhance efficiency and actual use of architectural cultural property records if one governmental body undertakes uniting records through standardization and professional supervision, and data-based unified search engine would enhance efficiency and actual use. Therefore, I suggest that Archives for Architectural Cultural Properties should be established as a professional Archives and wholly responsible body for the purpose of systematically and unifiedly managing architectural cultural property records with professional personnel and facility and transmitting their historical, cultural, and academic value. In Korea, studies up to the present have mainly focused on managing architectural records and records of drawing while few efforts were made to directly deal with managing architectural cultural properties themselves. The focus of this thesis is to study the current status and establish problems of the management of architectural cultural properties in administrative process, and as a result, to propose to establish Archives for Architectural Cultural Properties as a professional archives.

• Food Science and Industry
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• v.51 no.4
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• pp.278-301
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• 2018

Although more than 80% of living organisms are found in marine ecosystems, only less than 10% of marine resources have been utilized for human food consumptions and other usages. It is well known that marine resources (fish, shellfish and algae) have exceptional nutritional properties; however, their functional characteristic has not been completely discovered. It is believed that metabolites (organic compounds, proteins, peptides, lipids, minerals, etc.) play an important role to show its biological properties. Marine proteins and peptides are considered to be future drugs due to their excellent biological activities with a fewer adverse side effect. Marine peptides show several biological activities, including antimicrobial, antioxidant, anti-inflammatory, anti-cancer, anti-viral, anti-tumor, anti-diabetic, anti-hypertensive, anti-coagulant, immunomodulatory, appetite suppressing and neuroprotective effects. Therefore, the pharmaceutical, nutraceutical, and cosmeceutical companies have been paid attention to the marine peptides to commercialize into products. This current review mainly focused on the above mentioned biological activities of marine peptides and protein hydrolysates as a functional food and pharmaceutical applications. To commercialize these materials in industrial level required large quantity in high-purity level, and it is complicated to produce huge quantity from the marine resources due to insufficient raw materials, unavailability of raw materials through a year, hinder the growth with geographical variations, and availability of compounds in extreme small quantities. The best solution for these issues is to introduce new modern technologies such as artificial intelligence robots, drones, submersibles and automated raw material harvesting vessels in farming industries instead of man power, which will lead to 4th industrial revolution.

• 대한공업교육학회지
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• v.44 no.1
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• pp.23-51
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• 2019

The purpose of this study was to analysis school dropout of specialized vocational high school students using phenomenological research method. The interview for the research was carried out with 10 adolescents who dropped out specialized vocational high school from December 8 to 23, 2018. According to the result of the research, 31 themes were extracted from interviews with 10 research participants. And 10 theme clusters were categorized from these. And these clusters were divided into 3 domains : 'before school dropout', 'causes & process of school dropout, feeling about school dropout', 'after school dropout' Based on the finding of the study, major conclusions of this study were as follow: First, adolescents who dropped out specialized vocational high school suffered from hard school life, disappointing lead from teachers, stereotypical lesson. And they committed misdeeds, and had psychological difficulties. Some of them kept up the good relationship with their friends, teachers, parents, some of them did not. Some of them kept up the good relationship with their friends, teachers and parents, while some of them did not. Second, they chose dropout due to various different causes. The procedures of school dropout proceeded with comparative ease. The effect of dropout prevention program is very limited. The feeling they felt at the time of school dropout varied individually. Some adolescents who dropped out specialized vocational high school were satisfied while others were stressed out, regretting their decision. Third, they lived diligently working part-time jobs or preparing General Equivalency Diploma (GED) test after dropout. They experienced positive changes in their daily lives after dropout. But sometimes they experienced various difficulties and negative changes. Most of them had their goals, and they were preparing for them. Their expectation was low that their life will succeed if they returned to school. They wanted people to understand their decision about dropout. And multiple institutions are supporting adolescents who dropped out specialized vocational high school. They need practical support : Various information, activity for career experience, counseling etc.

• Economic and Environmental Geology
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• v.51 no.6
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• pp.473-483
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• 2018

Green-blue coloured supergene minerals are covering host rocks along the gallery wall in the Gukjeon mine, a lead - zinc skarn deposit located in Miryang, Gyeongsangnam-do. These minerals have been described as azurite or malachite, but recent study recognized that the green minerals are devilline and blue minerals are Cu-Zn hydrated sulfates, but exact identification and detailed mineral characteristics are also not well known. In this study, we divide green-blue minerals into five groups (GJG) according to their external features and conducted XRD and SEM analyzes in order to identify mineral name and clarify the mineralogical characteristics. GJG-1, a bright bluish green group, consists of brochantite and quartz and GJG-2, a pale green colour with easily crumbly, of schulenbergite and a small amount of gypsum. Although pale blue GJG-3 and glassy lustrous bluish green GJG-4 have the same mineral assemblages with serpierite and gypsum in spite of different colour and luster, gypsum content may control the physical properties. GJG-5 with a gel phase mixture of pale blue and dark blue mineral is comprised of hydrowoodwardite, glaucocerinite, bechererite, serpierite and gypsum. The six green-blue minerals from the Gukjeon mine could be classified by Cu:Zn ratio, (Si + Al) content, Si:Al ratio, and Ca content. The physico-chemical environment of mineral formation is considered to be controlled by the geochemical factors in the surrounding fluid, and it looks forward that the accurate formation environment will be revealed through additional research. This paper gives greater mineralogical significance in the first report of several hydrated sulfate such as serpierite, glaucocerinite and bechererite in Korea. It has also rarely been reported the occurrence of several Cu-Zn hydrated sulfate in the same deposit in the world.

• Korean Journal of Heritage: History & Science
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• v.42 no.4
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• pp.74-95
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• 2009

Folk villages have higher historic and cultural values than other villages and contain considerably many traditional elements today. In Korea, there are seven folk villages that are under the protection of the Cultural Properties Protection Act. Unlike other kinds of tangible cultural assets individually appointed according to the act, those folk villages are protected by the act in entirety including the houses and auxiliary structures inhabited and used by the villagers. Since the act covers the entire villages, the residents are not allowed to repair or renovate their structures and accordingly suffer from huge limitations in everyday life with housing life under the biggest restrictions. Being appointed as a folk village is positive from the perspective of preserving the village. However, it is negative to the villagers because of the limitations to their housing lives. While common people lead a convenient life by the introduction of high technologies in modern society, they do not get to benefit from such technologies for the cause of preserving the traditional culture. Upon the appointment, they are subject to all sorts of building regulations and under huge direct and indirect influences of those regulations across many different aspects of life including housing life. Thus the residents of folk villages do have many complaints about the act. It is only natural that there occur conflicts between the state, which tries to preserve the traditional culture according to the act, and the residents, who pursue convenience in life. At the same time, it is natural too that the residents have the desire to pursue convenience in daily life. Thus they renovate their houses illegally. The government agencies are aware of that, however, it is not right for them to enforce the act and restrict their daily lives. Their tacit approval of such illegal renovations is the product of compromises between the residents' right to their private property and the state's policies of cultural asset protection. The residents try to renovate their houses within the limit that will not call for legal restrictions from the government agencies. The government allows for renovations as long as they are within the minimum limit. It is the result of efforts for the state and the residents to stitch up and compromise their own complaints.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.112-131
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• 2011

This article reports the results of scientific analysis using SEM-EDX, XRD, TG/DTA, performed on 5 green glaze samples of the brick and roofing tile excavated from the Sacheonwang temple site in Gyeongju in order to verify the chemical compositions and melting temperature. The glaze samples on 2 clay statues have similar chemical composition (PbO 74~81%, $SiO_2$ 14~18%) and melting temperature range ($970{\sim}1070^{\circ}C$), whereas the 2 tiles of goblin's face and 1 rhomb brick have different characteristics. Sample SC 003 (made of PbO 63~67%, $SiO_2$ 25~28%), one of the tiles of goblin's face, shows low melting temperature range (below $970^{\circ}C$), and sample SC 004 (composed of PbO 64~70%, $SiO_2$ 19~25% and melting point $970{\sim}1070^{\circ}C$), the other tile of goblin's face, shows different chemical characteristics compared with 2 clay statues. The green glaze on rhomb brick shows different composition compared with all the others from Sacheonwang temple site in that it does not show any impurity elements other than the main components (PbO 87~88%, $SiO_2$ 12~13%) with very low melting temperature range ($750{\sim}770^{\circ}C$). Surprizingly, the chemical and optical characteristics of this green-glaze on rhomb brick are very similar to that on the bricks from Yeongmyo temple site, Gyeongju. The above results indicate that raw material and manufacturing method are not same for 5 green-glaze samples from Sacheonwang temple site and therefore suggests that further study on the provenance of raw material such as lead isotope analysis is necessary. Our work will provide basic data for future reproduction study of green glazed brick of Sacheonwang temple site, Gyeongju and will also serve as a reference data for the study of raw material and manufacturing method of green glaze from other sites of cultural assets.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.132-149
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• 2011

In ancient period, a variety of inorganic or organic pigments had been used as colorants in various kinds of religious and secular paintings such as tomb paintings and wall and scroll paintings in buddhist temples, and danchung(cosmic patterns) for the surface of wooden buildings. This study discusses the results obtained from an analysis of the pigments on the wall paintings of Yeongsanjeon(Hall of Vulture Peak) in Tongdo temple by a qualitative analysis using a field-XRF. The results can be briefly summarized as follows. Firstly, assuming from the major components examined from F-XRF analysis, raw materials of pigment of each color are: red to be Cinnabar(HgS) or Hematite($Fe_2O_3$); white to be White Lead[$2PbCO_3{\cdot}Pb(OH)_2$] in most cases and Calcite($CaCO_3$) or Chalk($CaCO_3$), Kaolin($Al2O_3{\cdot}SiO_2{\cdot}4H_2O$) in some cases; yellow to be Yellow Ocher[$FeO(OH){\cdot}nH_2O$]; black to be carbon(C); green on the painted surface to be Celadonite[$K(Mg,Fe^{2+})(Fe^{3+},Al)(Si_4O_{10})(OH)_2$] in most cases; dark green on the halo of figures to be Malachite[$CuCO_3{\cdot}Cu(OH)_2$], Copper Green[$2CuO{\cdot}CO_2{\cdot}H_2O$] or Atacamite[$Cu_2Cl(OH)_3$]. Secondly, incarnadine and pink were made by mixing with more than two pigments such as red and white for making various tone of colors. The qualitative analysis of pigments on the wall paintings of Yeongsanjeon, in conclusion, displays that the all pigments for ancient periods are inorganis pigments. However, it has the limitation to identify a definite kinds of mineral for each pigment because it was not possible to collect samples from cultural heritage for conducting a crystalline analysis of XRD.