• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.623-631
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• 2007

Effect of Soft-start curing on the contraction stress of composite resin restoration polymerized with LED and plasma curing unit The purpose of this study was to evaluate the influence of soft-start light curing on contraction stress and hardness of composite resin. Composite resin (Filtek $Z-250^{TM}$, 3M ESPE, USA) was cured using the one-step continuous curing method with three difference light sources ; conventional halogen light ($XL3000^{TM}$, 3M ESPE, USA) cure for 40 seconds at $400 mw/cm^2$, LED light (Elipar Freelight $2^{TM}$, 3M-ESPE, USA) cure for 20 seconds at $800\;mW/cm^2$ a and plasma arc light ($Flipo^{TM}$, LOKKI, France) cure for 12 seconds at $1300 mW/cm^2$. For the soft-start curing method ; LED light (Elipar Freelight $2^{TM}$, 3M-ESPE, USA) cure exponential increase with 5 seconds followed by 17 seconds at $800\;mW/cm^2$ and plasma arc light ($Flipo^{TM}$, LOKKI, France) cure 2 seconds light exposure at $650\;mW/cm^2$ followed by 11 seconds at $1300\;mW/cm^2$. The strain guage method was used for determination of polymerization contraction. Measurements were recorded at each 2 second for the total of 800 seconds including the periods of light application. Obtained data were analyzed statically using Repeated measures ANOVA, One way ANOVA, and Tukey test. The results of present study can be summarized as follows: 1. Composite resin restoration showed transient expansion just after irradiation of curing light. Contraction stress was increased rapidly at the early phase of polymerization and reduced slowly as time elapsed (P<0.05). 2. Contraction stress was not revealed significant difference between Halogen curing light groups and LED and Plasma Light curing with soft-start group (P>0.05). 3. LED and Plasma Light curing with soft-start showed lower contraction stress than the one-step continuous light curing (P<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1312-1317
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• 2008

Physicochemical changes were investigated for the shelf-life extension of cultured wild-ginseng roots during storage with various pre-treatments with blanching, CAMICA-SD and DF-100 and treatments with citric acid and vitamin C. The pH of cultured wild-ginseng roots showed the range of $6.06{\sim}6.42$ at $10^{\circ}C$, but showed higher ranges of $6.08{\sim}6.91$ and $6.08{\sim}8.68$ at 20 and $30^{\circ}C$, respectively. Browning index (a/b) was increased with increasing storage temperature, and the index at 10 and $30^{\circ}C$ were 0.405 and 0.469 after 2 weeks, respectively. Browning index and viable cell number of CAMICA-SD pre-treatment showed little changes compared to pre-teatment with blanching or DF-100. When the cultured wild-ginseng roots were treated with 1.0% citric acid and 0.2% DF-100 after pre-treatments with CAMICA-SD, viable cell number was slightly increased to $4.9{\times}10^2CFU/g$ for 3 weeks storage at $10^{\circ}C$. The mixture of citric acid and DF-100 was also used to prevent the growth of microbiology and to reduce browning reaction, especially enzymatic browning reaction. The mixture might effectively extend shelf life of the cultured wild-ginseng roots.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.980-987
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• 2012

Nonpoint source pollution causes leaks and overtopping, depending on the state of the sewer network as well as aggravates the pollution load of the aqueous water system as it is introduced into the sewer by wash-off. According, the need for efficient sewer monitoring system which can manage the sewage flowrate, water quality, inflow/infiltration and overflow has increased for sewer maintenance and the prevention of environmental pollution. However, the sewer monitoring is not easy since the sewer network is built in underground with the complex nature of its structure and connections. Sewer decontamination mechanism as well as pipe network monitoring and fault diagnosis of water network system on system analysis proposed in this study. First, the pollution removal pattern and behavior of contaminants in the sewer pipe network is analyzed by using sewer process simulation program, stormwater & wastewater management model for expert (XP-SWMM). Second, the sewer network fault diagnosis was performed using the multivariate statistical monitoring to monitor water quality in the sewer and detect the sewer leakage and burst. Sewer decontamination mechanism analysis with static and dynamic state system results showed that loads of total nitrogen (TN) and total phosphorous (TP) during rainfall are greatly increased than non-rainfall, which will aggravate the pollution load of the water system. Accordingly, the sewer outflow in pipe network is analyzed due to the increased flow and inflow of pollutant concentration caused by rainfall. The proposed sewer network monitoring and fault diagnosis technique can be used effectively for the nonpoint source pollution management of the urban watershed as well as continuous monitoring system.

• Korean journal of communication and information
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• v.39
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• pp.250-283
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• 2007

The Shinmoongo (Shinmoon-drum) system is known as the last means of petition, appeal, and, denunciation during the Chosun dynasty. The purpose of this study is first to examine the system's origin and changes of its function and operation. The study further looks at several issues around the striking gong system, an alternative appealing method, and its background and transition. Introduced by King Taejong, the Shinmoongo was a kind of the press (or communication) system which was intended to deliver various cases of personal appeal, social petition, national denunciation, etc. Since the 2nd year of King Sejong, the system had been changed into the legal system which mainly to settle personal mortifying problem. Originally, the system was institutionalized for the common people who were hard to appeal their mortifying affairs to the supervisory administration. This reporting system to a superior was utilized as an institutional device to remedy abuses from 'complaint to the King near his sedan chair' and 'direct complaint out of order' during the early disordered years of Chosun dynasty. The system was often abused for the devices of private interest by illustrious officials. Meanwhile, it carried out a role of checking power abuses of provincial governors and magistrates. There were many obstacles for the common people and lowly people to turn to the means. The drum was located at the palace of capitol, less accessible for most people at the time. The petition had to be processed through several steps in written forms. The punishment on a false drummer was heavy. It inhibited any appeal concerning the superior under the rigorous caste system. The Shinmoongo system is regarded as a legitimate press system. Also, it is taken as informal or semi-official press system such as 'document to send around', 'document for agitation', 'joint petition', 'striking gong to complain', 'complaint to the King near his sedan chair', 'scream to complain', etc. Connecting together, the tools resulted in the increase of regal power and decrease of divine authority.

• Journal of Korean Home Economics Education Association
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• v.16 no.3
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• pp.1-25
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• 2004

This study analyzes the external forms of the household textbooks and also the contents of them used at girls' middleㆍhigh schools during the period of Japanese ruling over Korea. To this end, 8 household textbooks published from 1928 to 1937 were analyzed. The results of the study are summarized as follows. 1. The household subject had become the one of the most important subjects to girl students as the practical uses were emphasized in educational area during the period. As a result. the classes of the household were the second in hours, following the class of Japanese (the national language) to girl students. 2. The contents of the household textbooks were intended to contain 'the modern' and 'the newest'. The students were also suggested to apply the contents of the textbooks to real home life. Many pictures, photos and illustrations were included in household textbooks to help students to understand the contents of the subject. 3. The purposes of the household class were the reformation of the living conditions and home economics. 4. The external characteristics of the household textbooks during the period were as follows. - Written in Japanese vertically and the size of the textbook was A5 (150/210) with pulp paper of good quality - The type style of the body of the textbooks was Ming-style type- The sequent order of the textbooks was the outer cover, the title page, pictorial, introduction, table of contents, the body, appendix and the back cover. 5. The household textbooks consisted of the first volume and the second volume. The first volume contained clothing and textiles, food and nutrition and housing. Taking care of the aged. nursing. child care, household economy and home management were included in the second volume. 6. The household textbooks were designed to make women the housewives.

• KDI Journal of Economic Policy
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• v.13 no.2
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• pp.41-67
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• 1991

Local autonomy of Korea's lower-level local council has been reinstated following elections last March for the first time in thirty years. Last June, we had elections for the upper-level local council. Mayors, governors, and administrative chiefs of cities, provinces and other local government bodies are slated for elections in the first half of next year. The impacts of local autonomy are taking effect in not only the political sphere, but also the administrative and economic spheres. In fact, it seems that some modification of all economic policy making and administration is inevitable. Since the initiation of local autonomy, in order to make the economy work more efficiently, it has become quite important to examine the impact of local autonomy on the national economy. The areas of local autonomy include independent legislative power, administrative power, organizational power, and most important of all, the independent public financial power of the local governments. The purpose of this paper is to examine the effects of local autonomy on the national economy and ways of enhancing the role of local public finance to facilitate settlement and development of the local autonomy system. Local autonomy will contribute to the continuous growth of our economy, allow balanced development, and generate greater efficiency. However, local autonomy can also incur economic costs causing at times short-term price instability, inefficient resource allocation, through tax competition and tax exporting, and insolvency of local government due to abusive fiscal operation. To reduce these side effects, different alternatives must be considered. Local autonomy systems generally provide more efficient resource allocation than centralization. But in the model used in Chapter 3 of this paper, the relative efficiencies of both local autonomy and centralization are determined by comparing the elasticity of substitution between national public goods and local public goods. If the elasticity of substitution is bigger than one, centralization provides a more efficient resource allocation. The development of local autonomy could be attained through democratization of the local public finance system including the following three propositions. I) The independence of public financial power of local governments should be established over central government. Furthermore, a democratically operated scheme of intergovernmental fiscal coordination is especially necessary. 2) In the operation of local finance, direct democracy is needed to induce the voluntary participation of local residents. The residents can take part in planning both the local budget and the development of the community. To attain this goal, all the results of local finance operations should be made public. 3) Among economic ill-effects of the local autonomy system, the most serious one is the possibility of insolvency of local governments. Therefore, measures to limit abusive spending by the local governments should be introduced, such as the fiscal restraints system adopted in the United States.

• Journal of Life Science
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• v.18 no.11
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• pp.1561-1569
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• 2008

This study was conducted to investigate the effects of steam flaking of corn grains on in situ dry matter degradability in the rumen and contents of mycotoxins (aflatoxin, ochratoxin) during storage. Yellow dent corns imported from USA and India were flaked, and stored for 8 weeks under the standard temperature and pressure (STP; $25^{\circ}C$/ 1 atm.). Experimental treatments were composed of four corn grains (untreated-USA corn, USCW; steam flaked-USA corn, USCF; untreated-India corn, IDCW; steam flaked-India corn, IDCF) with 4 replications according to 9 storage periods (0, 1, 2, 3, 4, 5, 6, 7, 8 week). Two ruminally cannulated Holstein bulls were used for in situ trial. Pathogen contamination trial was performed by comparing the mycotoxin contents in corns during storage periods. Dry matter disappearance rate in the rumen was about 3.0 to 44.1% higher (P<0.05) for USCW than IDCW, but was not difference between USCF and IDCF. With steam flaking of corn, dry matter degradability in the rumen was significantly (P<0.05) increased in corn from India, but was not affected in corn from USA. Aflatoxin content was very low level in corns from USA and steam flaked corns, but was higher than the tolerance limit of domestic aflatoxin content regulation when IDCW was stored over 6 week under STP. Ochratoxin content was low level in all treatments. From above results, it is reasonable that the corn imported from India might be flaked for enhance the ruminal DM degradability and safe from aflatoxin pathogen.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.264-271
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• 1999

This study was conducted to know the storage stability of Yackwa, a traditional Korean fried cookie, prepared by two different cooking methods; deep fat frying at 160$^{\circ}C$ for 8 min (DFF), and preheating Yackwa dough and then deep fat frying at 180$^{\circ}C$ for 2 min (MW/DFF). Soybean oil (SBO), hydrogenated soybean oil (HSBO) or hydrogenated palm oil (HPO) were used for frying Yackwa. Compared to Yackwa prepared by DFF, all MW/DFF Yackwa samples had low fat content and high moisture content. MW/DFF saved frying time 6 min compared with DFF. Non-hydrogenated soybean oil for frying fats was replaced with hydrogenated types of soybean oil and palm oil to improve the storage stability of Yackwa. To investigate the oxidation stability of Yackwa during the accelerated storage for 15 days at 60$^{\circ}C$, acid value, anisidine value, peroxide value and oxidation value of Yackwas were measured. Acid values of Yackwa made by MW/DFF were higher than those made by DFF through the whole storage periods, regardless of frying fats. Peroxide and anisidine values of Yackwa coated with syrup were much lower than those without syrup. MW/DFF cooking method, using hydrogenated soybean oil or hydrogenated palm oil for frying, showed lowering effects on peroxide value as well as anisidine value, resulting in improved oxidation stability of Yackwa during the storage. In sensory evaluation, the acceptability of MW/DFF Yackwa was higher than those of the commerical products. Yackwa prepared by MW/DFF cooking method using hydrogenated palm oil, showed the highest acceptability in color, taste and texture among the samples.

• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.35-46
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• 2015

Recently, much attention has been paid to the development of a value-added food category containing probiotics so as to improve human health and prevent diseases. Among various foods, the health benefits of milk and dairy products are known to humanity, and could be attributed to the bioactive components present in milk. In fermented milk products, the health benefits could be due to suitable modulation activities produced by the action of probiotic bacteria. Besides the modification of various milk components, probiotics might also act directly as preventive and therapeutic agents against some severe diseases. Probiotics promote health via their positive effects on the immune response, stimulation of natural immunity, and modulation of the production of antimicrobial peptides, cytokines, and so on. Whey proteins, a byproduct of cheese production could also have anticarcinogenic, immunostimulatory, antimicrobial, and health-promoting activities such as improving insulin sensitivity and reducing fat deposition. Therefore, milk and dairy products containing probiotics could provide various opportunities in the field of functional foods. Additionally, these functional foods may be important in the human diet and may help improve human health and prevent diseases.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.207-220
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• 2012

There are around 7,500 manure tanks to treat the manures from pigs in Korea. In the tank, there are too much sediments deposited on the base and wall, which causes low efficiency of stock capacity and manure fermentation. In order to minimize sediments and to ferment manure effectively, we developed a 2-fluid jet mixer for mixing sediments in liquid livestock manure tank. For developing the prototype, we tested a factorial experimental system with various nozzles, and simulated CFD models with two kinds of nozzle arrangement. From the results of factorial experiment and CFD simulation, we concluded the dia. ratio of primary : secondary nozzle should be 1:2 and the nozzles should be arranged at the same distances toward to the circumferential direction. With this results, we manufactured a 2-fluid jet mixer which is consists of four 2-phase nozzles, centrifugal slurry pump and root's type air blower. And, we carried out the performance test of the prototype in the round shaped liquid manure tank in the farm. The performance test results showed that the uniformity of TS (Total Solid) and VS (Volatile Solid) was raised from 21.3 g/L, 13.3 g/L In steady state to TS and VS to 23.0 g/L, 14.1 g/L in the mixing operation. Therefore, we could conclude that the prototype of 2-fluid mixer could make the solid material which could be sediments in the tank not to be deposited in the tank and to be contacted to air bubbles which could enhance the efficiency of the fermentation of livestock manure.