• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.93-99
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• 2019

The purpose of this study was to investigate the bond strength between PEKK(Polyetherketoneketone) and Sinfony(3M ESPE, Seefeld, Germany) the dental composite resin by proposing the three representative surface treatment methods and evaluate to see if they affect the bond strength between two materials. A total of 30 PEKK($Pekkton^{(R)}$ Ivory, $Cendres+M{\acute{e}}taux$, Bienne, Switzerland) specimens were prepared, embedded in acrylic resin, polished(P 1200 grid) to surface, and each group was divided into 10 specimens. After then, by the surface treatment method, it classified into three groups(n=10) such as Air abrasion group(PN), applying Single Bond Universal(3M ESPE) after Air abrasion(PB), applying OPAQUE(3M ESPE) after Air abrasion(PO). Then, veneering was performed by using Sinfony(3M ESPE, Seefeld, Germany). All completed specimens were allowed to rest in a $37^{\circ}C$ water bath for 24 hours. Shear bond strength of each group was measured and fracture patterns were classified. Statistic analysis was performed with One-way ANOVA followed by post hoc Scheffe tast (p<.05). Statistical analysis was performed using the SPSSWIN 21.0 program. As a result of one-way ANOVA, the average value of PB group was $27.67{\pm}4,18MPa$ and it was shown as the highest bond strength, PN and PO were $20.43{\pm}1.70$ and $19.8{\pm}4.77MPa$ each, and these were relatively low(F=18.4, P<.001), and as the post-test the Scheffe test was conducted and verified (p<.05). After examining the scheffe test, it was showed significant differences as PB>PO, PB>PN(p<.001). Through this study, in order to enhance the bonding force between PEKK and the composite resin, perform the Air abrasion and surface treatment by using Single Bond Universal(3M ESPE) is recommended, and as coMPared with other studies. And it is assumed that the increase of the application time of the Air abrasion affects the increase of the shear bond strength. Thus, further research is required.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1108-1119
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• 2018

As the interest on the air pollution is gradually rising at home and abroad, automotive and fuel researchers have been studied on the exhaust and greenhouse gas emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward two main issues : exhaust emissions (regulated and non-regulated emissions, PM particle matter) and greenhouse gases of vehicle. Exhaust emissions and greenhouse gases of automotive had many problem such as the cause of ambient pollution, health effects. In order to reduce these emissions, many countries are regulating new exhaust gas test modes. Worldwide harmonized light-duty vehicle test procedure (WLTP) for emission certification has been developed in WP.29 forum in UNECE since 2007. This test procedure was applied to domestic light duty diesel vehicles at the same time as Europe. The air pollutant emissions from light-duty vehicles are regulated by the weight per distance, which the driving cycles can affect the results. Exhaust emissions of vehicle varies substantially based on climate conditions, and driving habits. Extreme outside temperatures tend to increasing the emissions, because more fuel must be used to heat or cool the cabin. Also, high driving speeds increases the emissions because of the energy required to overcome increased drag. Compared with gradual vehicle acceleration, rapid vehicle acceleration increases the emissions. Additional devices (air-conditioner and heater) and road inclines also increases the emissions. In this study, three light-duty vehicles were tested with WLTP, NEDC, and FTP-75, which are used to regulate the emissions of light-duty vehicles, and how much emissions can be affected by different driving cycles. The emissions gas have not shown statistically meaningful difference. The maximum emission gas have been found in low speed phase of WLTP which is mainly caused by cooled engine conditions. The amount of emission gas in cooled engine condition is much different as test vehicles. It means different technical solution requires in this aspect to cope with WLTP driving cycle.

• Korean Journal of Heritage: History & Science
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• v.49 no.1
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• pp.146-165
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• 2016

With the introduction of the system of recognizing masters of craft and performance skills in 1970, the principle of "preserving the original form," which was already in general use, was adopted as a legal principle in the Cultural Heritage Protection Act. While the concept "original form" can be related to tangible elements of heritage through the Act, the intangibility of craft and performance skills does not allow their pinpointing at a particular temporal period or the identification of a particular master from the past as the basis of an original form. Therefore, those craft or performance skills that are available at the point of recognition of relevant masters must serve as the basis of the original form for the intangible heritage concerned. This means that the principle of preserving the original form of intangible heritage has been implemented not based on a fundamental form of materiality, but rather on the craft or performance skills that may be held by a master at the time of his/her recognition as a "temporary original form." This principle has been observed through intangible heritage transmission and education policies for recognized masters and their trainees, contributing to establish an elitist transmission environment in which public were denied to join the education on intangible heritage. Even with policies guided by the principle of preserving the original form, designated craft and performance skills have been transformed contingent upon given social and environmental conditions, thus hindering the preservation of the original form. Despite the intrinsic limitations of the principle of preserving the original form when applied to intangible heritage, this principle has served as a practical guideline for protecting traditional Korean culture from external influences such as modernization and Westernization, and also as an ultimate goal for the safeguarding of intangible heritage, engendering actual policy effects. The Act on the Safeguarding and Promotion of Intangible Cultural Heritage that comes into effect in March 2016 takes the constantly evolving nature of intangible heritage into consideration and resultantly adopts a concept of "essential form" (jeonhyeong) in place of "original form" (wonhyeong). This new concept allows for any transformations that may take place in the environment surrounding the intangible heritage concerned, and is intended to mitigate the rigidity of the concept of "original form." However, it should be noted that "essential form," which is manifested as the unique significance, knowledge, and skills delivered by the intangible heritage concerned, should be maintained according to the guidelines and principles related to heritage conservation. Therefore, the new concept can be understood not as a rupture, but more as a continuum of the concept of "original form."

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.19-30
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• 2019

Objective of this study was to develop an organic fertilizer utilizing domestic livestock horn meal and to investigate the application effect of rice and eggplant. The possibility of utilization of livestock horn meal as an organic resource to replace imported expeller cake fertilizer was examined. In order to select domestic organic resources with high nitrogen content, 8 kinds of organic matter such as chicken manure, fish meal, soybean meal, sesame meal, perilla meal, blood meal, livestock horn meal, and beer sludge were analyzed and organic resources with high nitrogen content were selected. In addition, the conditions for the production of organic fertilizers that can be used in organic agriculture were established by mixing of the rice husk biochar and the rice bran as the supplements with the raw materials for mixing ratios. The content of total nitrogen (T-N) in the livestock horn meal was 12.0 %, which was the next low in 13.5 % blood meal. The content of total nitrogen was 5.9 ~ 7.9 % in fish meal and oil cakes. Total nitrogen content of non-antibiotic chicken manure for organic farming was 3 % and nitrogen content in beer sludge was 3.5 %. Organic fertilizer was produced by using biochar, rice bran as a main ingredient of non-antibiotic chicken manure, livestock horn meal and beer sludge. Compared to nitrogen content (4.0 to 4.2 %) of imported expeller cake fertilizer (ECF), the nitrogen content of organic fertilizer utilizing domestic livestock horn meal is as high as 7.5 %. The developed organic fertilizer is met as Zn 400 mg/kg, Cu 120 mg/kg the quality of organic agricultural materials such as or less. To investigate the effect of fertilizer application on the crops, prototypes of developed organic fertilizer were used for the experiment under selected conditions. As a result of application the developed organic livestock horn meal fertilizer (LHMF) for cultivation of the rice and eggplant, the application quantity of the developed organic LHMF 100 % was decreased by 40 % compared to that of the mixed expeller cake fertilizer (MECF). The application of LHMF, which refers to the application rate corresponding to the nitrogen fertilization recommended by the soil test, was reduced by 40% compared to the application rate of MECF, but the same results were obtained in crop growth and yield. The selection of a new high concentration nitrogen source utilizing domestic organic resources and the development of organic fertilizer is the starting point of the research for substitution of imported ECF using domestic local resources at the present time that the spread of eco-friendly agriculture is becoming increasingly important. If it is expanded in the future, it is expected to contribute to the stable production of eco-friendly agricultural products.

• Korean Journal of Psychosomatic Medicine
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• v.26 no.2
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• pp.188-193
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• 2018

Objectives : Clozapine is a widely prescribed antipsychotic drug for schizophrenia and is known to increase the risk of cardiovascular disease due to its metabolic side effects. However, little is known about the effect of clozapine on the platelet activation, another important factor in the development of cardiovascular disease. In this study, we tried to investigate the effect of clozapine on platelet activity in patients with schizophrenia by comparing the mean platelet component (MPC) values before and after the clozapine administration. Methods : A retrospective review of medical records of patients with schizophrenia, who newly started clozapine treatment from September 1st, 2003 to April 30th, 2007 at the Department of Psychiatry, Konyang University Hospital in Republic of Korea was performed. The final statistical analysis included 14 participants. Bayer ADVIA $120^{(R)}$ system was used to measure MPC. Results : Among the 14 participants, five subjects were males (28.60%), and ten subjects were females (71.40%). The mean age of participants was $37.50{\pm}11.64years$. Average of duration of illness was $91.00{\pm}93.96months$, with the mean dosage of clozapine taken by participants at the time of the last blood test was $337.50{\pm}109.52mg$. The mean MPC measurement before and after receiving clozapine was $26.12{\pm}2.22g/dL$ and $25.14{\pm}2.08g/dL$ respectively. Wilcoxon signed rank test showed that there was a statistically significant decrease in MPC levels after clozapine administration (V=16, p=0.024). Conclusions : Decreased MPC levels after clozapine administration implies that clozapine may increase platelet activation which could have an adverse effect on the occurrence of thromboembolic disease. Our findings also suggest that careful monitoring of the risk factors of cardiovascular diseases, such as platelets activity, is necessary when administering clozapine.

• The Korean Journal of Archival Studies
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• no.24
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• pp.215-274
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• 2010

Iron-making industries of the country, regardless of age has been the focus. This makes the iron production technology and production techniques that result in increased economic activity and because of the central charge. Therefore, the social development of ancient iron-making technology is based on phase-sensitive. Modern steel making up the monopoly of the country's target under the strict control of production, distribution was. It is essential to produce iron weapons was a threat is because you can keep the throne in the hands of the forces that can cause side effects when I went was to block. This study created a rail Cholbi(iron monument) and the regional distribution pattern of the production, construction background, looked on. Cholbi(iron monument) for the production and recording "the Annals of the Joseon Dynasty" often appear in history books and many academic interests, but was off target. Compared to a stone monument that was not generally as well as the Japanese colonial period and over the course of modernization destroyed, damaged a lot of cases the cause may be found in front. Cholbi(iron monument), except for the gravestones of the Joseon Dynasty monument erected in honor of virtue, as an example of content that dominated a packman business, founding of the school and confirmed that a few were built as a special purpose. Cholbi(iron monument) compared to the production technology or the cost of the monument's difficulty in financing follows. Therefore Cholbi(iron monument) the establishment of the Joseon Dynasty through the background of the economic situation and the local government can look. And iron technology began complaining about the object of history, economic conditions, with the change of season has been a change in people's consciousness tells you. Important data of ancient history as an epigraph that has been as important, the Middle Ages to modern times ranging from newly born to the time Cholbi(iron monument) in the development of the country's documentary subject to change should have been brought. Based on these discussions changes the identity of the hero monument and production inspector, review of production through the Joseon Dynasty period Cholbi (iron monument) contemplated the significance is reflected in production.

• International Area Studies Review
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• v.21 no.4
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• pp.41-63
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• 2017

FDI can either be absorbed in the production cycle with domestic investment and create an inducement effect or it can remain as an exogenous factor and increase the volatility of GDP. The purpose of this paper is to research these different impacts that FDI could have. For that, the endogenous growth theory was employed. The statistic method used are the panel model for sectoral analysis, and GARCH model and VAR for time series analysis. Myanmar was selected as this paper's research subject because it is one of countries which had a colossal amount of FDI inflow recently. The panel analysis did not confirm the causality between sectoral FDI and sectoral GDP. The reason for this could be in the lack of data, since sectoral data exists yearly only during 2006-2016. Therefore this study conducted the times series analysis. According to the results, during 2006 until 2010, it showed signs of GARCH but the effect of FDI on GDP was nonexistent, which means FDI was not integrated into the domestic production cycle but stayed in residual terms. During 2011 to 2016, FDI seemed to affect the growth of Myanmar's GDP. The estimation confirmed the existence of GARCH and the Granzer causality test confirmed that FDI influenced the GARCH, which signified FDI increased the volatility of GDP. The VAR analysis showed responses of GDP to FDI was small(about 0.0007). This research assumes that FDI can be divided in two parts: one part which can be assimilated in the domestic production cycle and the other where it stays outside of the production cycle. The former creates production inducement effect and the latter only increases the volatility of GDP. According to this study, the latter outweighs the former impact in Myanmar.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.371-377
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• 2018

The fruits of Panax ginseng were extracted with 80% aqueous MeOH and the concentrates were partitioned into EtOAc, n-BuOH, and $H_2O$ fractions. The repeated $SiO_2$ and octadecyl $SiO_2$ column chromatographies for the EtOAc fraction led to isolation of five ginsenosides. The chemical structures of these compounds were determined as ginsenoside F1 (1), ginsenoside F2 (2), ginsenoside F3 (3), ginsenoside Ia (4), notoginsenoside Fe (5) based on spectroscopic analyses including nuclear magnetic resonance, MS, and infrared. Compounds 2-5 were isolated for the first time from the fruits of P. ginseng in this study. All isolated compounds were evaluated for cytotoxic activities against human cancer cell lines such as HCT-116, SK-OV-3, human cervix adenocarcinoma (HeLa), HepG2, and SK-MEL-5. Among them compounds 2, 4, and 5 showed significant cytotoxicity on cancer cells. Compound 2 exhibited cytotoxicity on SK-MEL-5, HepG2, and HeLa cells with $IC_{50}$ values of 82.8, 86.8, and $78.3{\mu}M$, respectively. Compound 4 showed cytotoxicity on HCT-116, SK-MEL-5, SK-OV-3, HepG2, and HeLa cells with $IC_{50}$ values of 24.5, 25.4, 26.3, 22.0, and $24.9{\mu}M$, respectively. Compound 5 did on SK-MEL-5 cell with $IC_{50}$ value of $81.7{\mu}M$. The cytotoxicity of ginsenoside 2, 4, and 5 isolated from the fruits of Panax ginseng showed strong inhibition effect against on cancer cells, all of which have a glucopyranosyl moiety on C-3.

• Korean Journal of Heritage: History & Science
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• v.46 no.1
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• pp.208-227
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• 2013

Twenty-seven bronze bowls excavated from the Goryo burial complex at Deobu-gol were examined for their microstructure and chemical composition to characterize the bronze technology practiced by commoners at the time. Results showed that the objects examined can be classified into four groups: 1) objects forged out of Cu-near 22%Sn alloys and then quenched; 2) objects cast from Cu-below 10% Sn alloys containing lead; 3) objects cast from Cu-10%~20% Sn alloys containing lead and then quenched; 4) objects forged out of Cu-10~20% Sn alloys containing lead and then quenched. This study revealed that the fabrication technique as determined by alloy compositions plays an important role in bronze technology. The use of lead was clearly associated with the selection of quenching temperatures, the character of inclusions and the color characteristics of bronze surfaces. It was found that the objects containing lead were quenched at temperatures of $520^{\circ}{\sim}586^{\circ}C$ while those without lead were quenched at the range of $586^{\circ}{\sim}799^{\circ}C$. The presence of selenium in impurity inclusions was detected only in alloys containing lead, suggesting that the raw materials, Cu and Sn, used in making the lead-free alloys for the first group were carefully selected from those smelted using ores without lead contamination. Furthermore, the addition of lead was found to have significant effects on the color characteristics of the surface of bronze alloys when they are subjected to corrosion during interment. In leaded alloys, corrosion turns the surface light green or dark green while in unleaded alloys, corrosion turns the surface dark brown or black. It was found that in fabrication, the wall thickness of the bronze bowls varies depending on the application of quenching; most of the quenched objects have walls 1mm thick or below while those without quenching have walls 1mm thick or above. Fabrication techniques in bronze making usually reflect social environments of a community. It is likely that in the late Goryo period, experiencing lack of skilled bronze workers, the increased demand for bronze was met in two ways; by the use of chief lead instead of expensive tin and by the use of casting suitable for mass production. The above results show that the Goryo bronze workers tried to overcome such a resource-limited environment through technological innovations as apparent in the use of varying fabrication techniques for different alloys. Recently, numerous bronze objects are excavated and available for investigation. This study shows that with the use of proper analytical techniques they can serve as a valuable source of information required for the characterization of the associated technology as well as the social environment leading to the establishment of such technology.

• Korean journal of applied entomology
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• v.58 no.2
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• pp.111-120
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• 2019

Riptortus pedestris (Fabricius) (Hemiptera: Alydidae) is an economically important insect pest of soybean and fruit trees. We investigated the temperature effects on the adult fecundity and longevity, and determined the parameters of oviposition models and life table at different constant temperatures 15.8, 19.7, 24.0, 27.8, 32.6, 34.0, and $35.5^{\circ}C$. R. pedestris females reproduced successfully from 19.7 to $35.5^{\circ}C$ except $15.8^{\circ}C$. The longevity of R. pedestris was longest at $15.8^{\circ}C$ and it decreased with increasing temperature (76.6 days at $19.7^{\circ}C$ and 20.6 days at $35.5^{\circ}C$). The number of total eggs and viable eggs was highest at $24.0^{\circ}C$ (193.5 and 151.2). Egg hatchability was highest at $27.8^{\circ}C$ (84.0%). We compared the results of oviposition models and life table parameters using both total eggs and viable eggs. The parameter value (c: the maximum reproductive capacity) (190 eggs) of temperature dependent total fecundity model using total eggs was higher than that of the model using viable eggs. When we analyzed the life table parameter the values of net reproductive rate and mean generation time using viable eggs were lower than those using total eggs. The oviposition models and life table analysis using viable eggs will be helpful to understand the real population transition of R. pedestris in agricultural system.