• Restorative Dentistry and Endodontics
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• v.32 no.4
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• pp.356-364
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• 2007

The purpose of this study was to assess the background color-interceptive ability ana opacity of opaque shade composites (Universal composite, Filtek Z350, Charisma, Clearfil ST, Palpaque Estelite, Esthet-X, and Metafil Flo). Twenty four background specimens (diameter 5.5 mm, thickness 3.0 mm) with Root dentin Mustard (Bisco, Schaumburg, IL, USA) were made. The CIE $L^*a^*b^*$ value of background specimens was measured by a spectrophotometer (Spectrolino, GretagMacbeth, Regensdorf, Switzerland). Three specimens in every group were filled on the background specimens. The surface color of samples was measured by a spectrophotometer in 3.0 mm and every thickness to 0.5 mm while grinding. The color difference in the background color along with 3.0 mm specimen gauged the masking effect in each thickness while grinding and polishing. The opacity was calculated in 1 mm thick specimens. The opacity was in the decreasing order of Clearfil ST, Metafil Flo, Filtek Z350, Palpaque Estelite, Universal composite, Charisma, and Esthet-X (p < 0.05). As the thickness get reduced, $L^*$ value showed decreasing, $a^*$ increasing tendency. The surface color difference between pair of the 3.0 mm thick specimen and after grinding in same opaque resin was above 3.3 except Clearfil ST and Metafil Flo. The color difference (${\Delta}E^*$) between pair of background specimen and opaque resin built-up specimen showed more than 10.0 regardless kinds and thickness. The variance in opacity characteristics and color of the opaque composites is dependent upon manufacturer. When using the opaque resin, the optical properties of each material must be considered as well as cavity.

• Journal of radiological science and technology
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• v.40 no.4
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• pp.549-556
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• 2017

This study compared the spatial scattered dose distribution according to whether the recently developed radiation shielding is used or not in order to understand the spatial scattered dose distribution of C-arm. The horizontal side distribution increased by $30^{\circ}$ in the interval of the radius 50 cm on the height of 95 cm based on the head of the patient, and it was measured by increasing $30^{\circ}$ with the interval of 50 cm in the vertical side of each horizontal side. In the same method, the radiation shielding was installed and measured. The result of measurement shows that the horizontal side of 50 cm distance was $0^{\circ}$, $90^{\circ}$ and $180^{\circ}$, was $1.77{\pm}0.12$, $1.90{\pm}0.13$, $2.12{\pm}0.14$, and $2.69{\pm}0.15mSv/h$ in the $270^{\circ}$ direction, and was $1.59{\pm}0.12$, $0.99{\pm}0.09$, $1.47{\pm}0.11$, and $1.37{\pm}0.11mSv/h$ after the use of the radiation shielding. In addition, the vertical distribution in horizontal direction $90^{\circ}$ with 50 cm distance was $30^{\circ}$, $60^{\circ}$, $120^{\circ}$, was $3.85{\pm}0.18$, $9.15{\pm}0.28$, $10.82{\pm}0.31$, and $5.40{\pm}0.22mSv/h$ in $150^{\circ}$, and was $2.03{\pm}0.13$, $4.32{\pm}0.19$, $2.76{\pm}0.16$, and $1.92{\pm}0.13mSv/h\;mR/h$ after the use of the radiation shielding. Both direction showed decrease according to the use of the radiation shielding. Therefore, radiation related workers who work in operating rooms should recognize the spatial scattered dose distribution exactly and need to try to prevent the risk of radiation exposure with proper protective measures.

• Korean Journal of Remote Sensing
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• v.30 no.5
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• pp.677-686
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• 2014

Sea ice covers wide area in Terra Nova Bay in East Antarctica where the Jangbogo Antarctic Research Station was built in 2014, which affects greatly on the sailing of an icebreaker research vessel. In this study, we analyzed the optimum sea route and sailable period of the icebreaker to visit the Jangbogo Antarctic Research Station by using sea ice concentration data observed by passive microwave sensors such as Special Sensor Microwave/Imager (SSM/I) and Special Sensor Microwave Imager/Sounder (SSMIS) for the last decade, and by using sea route of the Araon, an icebreaker of Republic of Korea, from 2010 to 2012. It is found that Araon sailed in the route of sea ice concentration up to 78%. Sailing speed of the Araon decreased due to increasing sea ice concentration. However, Araon maintained the speed close to the average speed for the entire sailing period (~11 kn) in the route of sea ice concentration up to 70%. Therefore, we confirm that the Araon can sail typically in the route which shows sea ice concentration below 70%. We derived annually available sailing period in recent 10 years for the sea route of the Araon in 2010, 2011 and 2012, which is defined as the period showing sea ice concentration below 70% through the route. Maximum sailable period was analyzed to be 61 and 62 days for the route of the Araon in 2010 and 2011, respectively. However, the typical sailing in the routes was unavailable in some years because sea ice concentration was higher than 70% through the routes. Meanwhile, the sailable period for the routes of the Araon in 2012 was observed in every year, which was a minimum of 15 days and is a maximum of 89 days. Therefore, we could suggest that optimum route of icebreaker to visit the Jangbogo Antarctic Research Station is the route of the Araon in 2012. High resolution images from SAR or optical sensors are necessary to investigate sea ice condition near shoreline of Jangbogo research station due to several kilometers of low resolution of sea ice concentration.

• Korean Security Journal
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• no.27
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• pp.129-159
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• 2011

Physical security has always been an extremely important facet within the security arena. A comprehensive security plan consists of three components of physical security, personal security and information security. These elements are interrelated and may exist in varying degrees defending on the type of enterprise or facility being protected. The physical security component of a comprehensive security program is usually composed of policies and procedures, personal, barriers, equipment and records. Human beings kept restless struggle to preserve their and tribal lives. However, humans in prehistoric ages did not learn how to build strong house and how to fortify their residence, so they relied on their protection to the nature and use caves as protection and refuge in cold days. Through the history of man, human has been establishing various protection methods to protect himself and his tribe's life and assets. Physical security methods are set in the base of these security methods. Those caves that primitive men resided was rounded with rock wall except entrance, so safety was guaranteed especially by protection for tribes in all directions. The Great Wall of China that is considered as the longest building in the history was built over one hundred years from about B.C. 400 to prevent the invasion of northern tribes, but this wall enhanced its protection function to small invasions only, and Mongolian army captured the most part of China across this wall by about 1200 A.D. European lords in the Middle Ages built a moat by digging around of castle or reinforced around of the castle by making bascule bridge, and provided these protections to the resident and received agricultural products cultivated. Edwin Holmes of USA in 20 centuries started to provide innovative electric alarm service to the development of the security industry in USA. This is the first of today's electrical security system, and with developments, the security system that combined various electrical security system to the relevant facilities takes charging most parts of today's security market. Like above, humankind established various protection methods to keep life in the beginning and its development continues. Today, modern people installed CCTV to the most facilities all over the country to cope with various social pathological phenomenon and to protect life and assets, so daily life of people are protected and observed. Most of these physical security systems are installed to guarantee our safety but we pay all expenses for these also. Therefore, establishing effective physical security system is very important and urgent problem. On this study, it is suggested methods of establishing effective physical security system by using system integration on the principle of security design about effective security system's effective establishing method of physical security system that is increasing rapidly by needs of modern society.

• Korean Security Journal
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• no.61
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• pp.285-305
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• 2019

In the bill of [Act on Certified Detective and Certified Detective Business] (hereinafter referred to as the Certified Detective Act) proposed and represented by the member of National Assembly, Lee Wan-Yong in 2017, the legislative point of view showed that various incidents and accidents, including new crimes, are frequently increasing as society develops and becomes more complex, however, it is not possible to solve all the incidents and accidents with the investigation force of the state alone due to manpower and budget, and therefore, a certified detective or private investigator are required. According to the decision of the Constitutional Court in June 2018, Article 40 (4) of the Act on the Use and Protection of Credit Information is concerned with 'finding the location and contact information of a specific person or investigating privacy other than commerce relations such as financial transactions' are prohibited. It is for the purpose of preventing illegal acts in the process of investigation such as the location, contact information, and the privacy of a specific person and protecting the privacy and tranquility of personal privacy from misuse and abuse of the personal information etc. Such 'privacy investigation business' currently operates in the form of self-employment business, which becomes a social issue as some companies illegally collect and provide such privacy information by using illegal cameras or vehicle location trackers and also comes to be the objects of clampdown of the investigative agency. Considering this reality, because it is difficult to find a resolution to materialize the legislative purpose of the Act on the use and protection of credit information other than prohibiting 'investigation business including privacy etc' and it is possible to run a similar type of business as a detective business in the scope that the laws of credit research business, security service business, the position of the Constitutional Court is that 'the ban on the investigations of privacy etc' does not infringe the claimant's freedom to choose a job. In addition to this decision, the precedent positions of the Constitutional Court have been that, in principle, the legislative regulation of a particular occupation was a matter of legislative policy determined by the legislator's political, economic and social considerations, unless otherwise there were any special circumstances, and. the Constitutional Court also widely recognized the legislative formation rights of legislators in the qualifications system related to the freedom of a job. In this regard, this study examines the problems and improvement plans of the certified detective system, focusing on the certified detective bill recently under discussion, and tries to establish a legal basis for the certified detective and certified detective business, in order to cultivate and institutionalize the certified detective business, and to suggest methodologies to seek for the development of the businesses and protect the rights of the people.

• Journal of Soil and Groundwater Environment
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• v.10 no.4
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• pp.1-12
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• 2005

Policies regarding to soil quality of the United States, the United Kingdom, the Netherlands, Germany, and Demark were analyzed to suggest Korean policy for improving soil quality concept and it's implementation. All countries met four criteria: I) Soil quality levels of contaminants are indebt to concept of contaminant risk to recipients (human and ecosystem); ii) Any soil quality value can't be a magic number to determine whether a site is contaminated or not. To determine risk of sites, risk assessment of the sites should be followed; iii) Concentrations of contaminants of sites are not always significantly certain to risk of human and ecosystem of the sites; and iv) Soil quality levels are adopted based on land uses and plans. Considering our rooms to improve policies and analysis of the other country reports on their legislations about soil quality levels, our policy implementation could be approached from these directions: i) Our concept for soil quality levels needs to develop in scientific and rational. ii) Soil quality levels and risk assessment should be implemented as determining tools of site contamination in parallel, and iii) Soil quality levels depending on land uses and plans should be developed in debt with rational and scientific concept of risk. Increasing efficacy of Korea policy regarding the soil quality levels would be in dept to applying concepts of SCL (Soil Contamination Level) and SRL (Soil Regulatory Level) developed, implementing soil quality levels and risk assessment of contaminated sites in conjunction, and classifying three distinctions of land uses based on sensitiveness of recipients (human and ecosystem) to contaminants in soil in this research.

• 보존과학연구
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• s.32
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• pp.5-24
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• 2011

Neunghwaji(Embossed patterned paper) is a unique paper used for a traditional book cover in Korea. The research was carried out to investigate Neunghwaji's features. Physical property was studied through a test of tensile strength and folding endurance. Also, comparative analysis of virus resistance and waterproof ability was undertaken on Neunghwaji. 1. Folding endurance test showed that strength of non-embossed CB and HB decreased during deteriorating duration. Embossed CN and HN showed the strength increasing at early stage and decreasing from the 27th day of the deteriorating duration. Tensile strength was decreasing in both cases as deterioration progressed. 2. Growth of Arthrinium sp. fungus on embossed paper was 10% less than plain paper while Cladosporium sp. showed 20~30% less growth. Amur cork dyeing(H) showed 10~30% lower fungi growth than Gardenia seed dyeing(C). The result indicated that embossed paper has better virus resistance than Hanji, and Amur cork dyeing has better virus resistance than Gardenia seed dyeing. 3. Average contact angle of CN, CB, HN, and HB was $85{\sim}92^{\circ}$ and NON-N and NON-B was $59{\sim}63^{\circ}$. In detail, CN's contact angle was $1{\sim}7^{\circ}$ higher than CB's; HN was $1{\sim}6^{\circ}$ higher than HB. Therefore, it was found that embossed paper has higher contact angle than Hanji thus the former has better waterproof ability. The research suggested production technique of Neunghwaji and studied its features related to the technique. Neunghwaji was confirmed to have superior quality to Hanji though further study regarding above test result is needed to complement the research.

• Korean Journal of Heritage: History & Science
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• v.53 no.2
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• pp.110-139
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• 2020

Reclamation is the act of creating new lands by constructing dikes in offshore tidal flats to utilize them for various purposes, including the establishment of farmland to secure food for an increasing population. Based on the fact that reclamation has resulted in drastic changes in the environmental, economic, social, and cultural aspects of land expansion and development, population movement, and the formation of cities since ancient times, I reviewed the value of reclamation sites and addressed the issue of how to preserve and utilize them. "Reclamation culture" refers collectively to the recognition and concept system, behavior styles, and cultural products created by changes in the environment, and the tangible, intangible, and natural heritage generated directly and indirectly by reclamation is defined as "reclamation cultural heritage". It shows that the historical background of reclamation accords with prevailing trends, and that the reclamation sites possess cultural heritage value due to their historical, academic, and scarce characteristics. Numerous reclamation cultural heritage sites at the Gwangwhal and Gyehwa dikes are on the verge of being destroyed, with their original function having ended after the construction of Saemangeum Sea Wall. I propose measures to preserve these under the principle that utilization is based on the basic premise of conservation. First of all, modern and contemporary reclamation sites must necessarily be designated and managed as registered cultural properties, local cultural heritage, future heritage, and agricultural heritage. In particular, as it has been confirmed that reclamation sites created after the Goryeo and Joseon dynasties and the 1950s have not been designated as cultural heritage sites. It is necessary to review the characteristics and values of such reclamation sites through a full survey of national reclamation data. Effective and sustainable utilization of reclamation cultural heritage, which has not been acknowledged in the past due to its close relationship with our lives, is necessary to search for hidden stories found within that heritage, to organize governance for the efficient use of reclamation resources, and to build a museum to collect and display the history and culture of the reclaimed areas. Finally, through links with countries with experience in reclamation, we will be able to cope jointly with international issues such as those pertaining to society, culture, and environment, and would be able to implement various projects to further the advancement of human beings.

• Korean Journal of Poultry Science
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• v.32 no.1
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• pp.35-41
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• 2005

The objectives of the present study were to investigate the effects of varying levels of dietary oil containing conjugated linoleic acid (CLA) on the egg production and fatty acid composition of egg yolk. Seventy-two 59-wk-old ISA Brown laying hens were randomly allotted to four dietary treatments, each consisting of three replicates with six birds per replicate. There were four treatments that consist of diets containing 0, 1, 2, or $3\%$ commercial CLA-containing oil. Egg production was not significantly different among the dietary treatments at 0, 2, 4, and 6 week. The proportion of saturated fatty acids such as C16:0 and C18:0 in egg yolk were increased, but that of monounsaturated fatty acid C18:1 was decreased by feeding CLA-containing oil supplementation. However, the proportion of polyunsaturated fatty acids such as C18:2 and C18:3 in egg yolk were not different among dietary treatments at 2 and 4 wk of the experiment. At 6 week, the proportion of C18:2 in egg yolk was decreased by feeding CLA-containing oil compared with the control. Polyunsaturated fatty acid:saturated fatty acid (P:S) ratio and n-6:n-3 polyunsaturated fatty acid ratio were similar across the treatments between 2 and 4 week. The P:S ratio was decreased by dietary CLA-containing oil supplementation at 6 week. The proportion of CLA in egg yolk was linearly increased with increasing levels of CLA-containing oil supplementation. In conclusion, dietary supplementation of CLA-containing oil to laying hens increased beneficially increased CLA content in their egg yolk.

• Korean Journal of Poultry Science
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• v.29 no.2
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• pp.141-148
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• 2002

Two experiments were conducted to investigate the effects of supplemental feather digests on the growth of broiler chicks and taurine content in the broiler meat. In experiment 1, a total of 40 broiler chickens(Ros $s_{R}$) were assigned to four dietary treatments: control(T1), regular feather meal(FM) diet(R-FM,T2), NaOH treated FM diet(NaOH-FM,T3), HNO) treated FM diet($HNO_{3}$ -FM, T4). In experiment 2, a total of 70 broiler chickens were assigned to seven dietary treatments: T1 to t4(same as those of Exp. 1), modified $HNO_{3}$ treated FM diet(M- $HNO_{3}$-FM, T5), hair meal diet(HM, T6) and 0.22% cystine supplemented diet(CYS, T7). Feather meals and hair meal were supplemented at the level of 5% in the diet. In experiment 1 and 2, weight gain of chicks frd with R-FM or NaOH-FM tended to be higher than control or $HNO_{3}$ -FM. In experiment 2, weight gain of chicks frd with CYS was the highest followed by R-FM, M-HN $O_3$-FM, NaOH-FM, control, HM and $HNO_{3}$ -FM. In experiment 1, taurine content in breast muscle of chicks fed NaOH-FM was sogmofocamtly higher(P<0.05) than control. In experiment 2, taurine content in breast muscle of chicks fed NaOH-FM and CYS tended to be higher than other groups. Taurine content in leg muscle was significantly different among treatments as NaOH-FM and R-FM being highest followed by M- $HNO_{3}$-FM, CYS, control, $HNO_{3}$ -FM and HM. Taurine content in the liver(Exp. 1 and 2) and heart(Exp. 2) were not significantly affected by the supplemental feather digests. These results indicated that 5% NaOH-FM in the diet was effective in increasing taurine content in breast and leg muscle of broiler chicks.s.