• Restorative Dentistry and Endodontics
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• v.34 no.2
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• pp.87-94
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• 2009

The purpose of this study was to assess the current materials, methods and difficulties according to the year of licence and educational background of Korean dentists in Class II direct composite resin restorations. Total 17 questions were included in the questionnaire. Questions were broadly divided into two parts: first. operator's information. and second. the materials and methods used in Class II posterior composite restoration. The questionnaire was sent to dentists enrolled in Korean Dental Association via e-mail. Total 12,193 e-mails were distributed to dentists. 2,612 e-mails were opened, and 840 mails (32.2%) were received from respondents. The data was statically analyzed by chi-square test using SPSS(v. 12.0.1, SPSS Inc. Chicago, IL, USA). Male dentists among respondents was 79%. 60.3% of the respondents acquired their licences recently (1998-2007), and 77% practiced in private offices. 83.4% have acquired their knowledge through school lectures, conferences and seminars. For the Class II restorations, gold inlays were preferred by 65.7% of respondents, while direct composite resin restorations were used by 12.1 % amalgam users were only 4.4% of respondents. For the restorative technique, 74.4% of respondents didn't use rubber dam as needed. For the matrix. mylar strip (53.4%), metal matrix (33.8%) and Palodent system (6.5%) were used. 99.6% of respondents restored the Class II cavity by incremental layering. Obtaining of the tight interproximal contact was considered as the most difficult procedure (57.2%) followed by field isolation (21 %). Among various bonding systems, 22.6% of respondents preferred SE Bond and 20.2% used Single Bond. Z-250 was used most frequently among a variety of composite resins.

• Applied Biological Chemistry
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• v.41 no.7
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• pp.533-538
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• 1998

In order to gain fundamental information on the utilization of lipids as energy source in mud-skipper, muscle lipids and their fatty acid composition were investigated with respect to life cycle-maturation (Aug), before-hibernation (Nov), and after-hibernation (Apr). Crude and neutral lipid were found to decrease from 1.2, 68.3% (Aug) via 0.7, 53.8% (Nov) to 0.4, 42.6% (Apr), respectively, whilst phospholipids and glycolipids increased from 29.5 and 2.2% (Aug) to 52.1 and 5.3% (Apr), respectively. In neutral lipids, TG contents gradually decreased from 53.8% (Aug) via 33.6% (Nov) to 23.1% (Apr), while FFA and sterol contents increased from 13.5 and 14.2% (Aug) to 22.3 and 24.5% (Apr), respectively. In phospholipids, PC content decreased from 61.2% (Aug) to 50.6% (Apr), while changes in PS and PE contents, as a whole, showed the opposite trends. In neutral lipids, the levels of some fatty acids such as 16:0, 16:1, 18:0, 18:1 and 20:5 $({\omega}3)$ were analyzed to be high, with the 20 : 5 being predominant, and the levels of saturated and monoene-acids gradually decreased, while polyene-acids increased in before and after hibernation. In before hibernation, 16:0, 16:1, 18:1 mainly decreased but 18:2, 18:3 $({\omega}3)$ and most of saturated and monoene acids such as 14:0, 14:1, 16:1, 18:0, 18:1 slightly decreased in after hibernation. From these findings, it was suggested that those fatty acids decreased during hibernation were used as a energy source, particularly 16:1 and 18:1 being most preferentially used. In phospholipids, the levels of 16:0, 18:0, 20:5 $({\omega}3)$, 22:5 $({\omega}3)$ and 22:6 $({\omega}3)$ were found to be high. Throughout the life cycle, the levels of monoene-acids in phospholipids stayed constant, whilst those of 18:2, 18:3 $({\omega}3)$ and saturated acids such as 16:0, 18:0 were found to be decreased gradually in before and after hibernation, whereas those for the high degree of polyene-acids such as 20:4 $({\omega}6)$, 20:5 $({\omega}3)$, 22:5 $({\omega}3)$, 22:6 $({\omega}3)$ increased, particularly 20:4 $({\omega}6)$, 20:5 $({\omega}3)$ being most increased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.195-202
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• 2016

The government has run and managed various forms of direct payment systems, such as the paddy and field direct payment, to ease the instability of farm incomes with respect to market opening, and preserve farm income. Direct payments to the agricultural sector is a center in the key policy instrument that plays an important role in income stabilization. Despite the large amount of spending in the farm unit, the status of direct payment, and policy effects the analysis of direct payments, such as stability of income contribution, are insufficient. This paper, using the farm unit DB in 2014 and 2015, performed farm level analysis of direct payment, and derived the implications of the performance evaluation system. As a result, the distribution of direct payment showed considerable bias to the left side compared to the normal distribution curve. Approximately half of the farms (49.3%) in 2014 DB should receive below 100,000 won per year by a direct payment. A larger-scale farm showed a significantly increased income effect and income stabilizing effect because direct payments make higher contributions to farm income in proportional to the area. In the more elderly farmers, a high contribution by direct payment to farm income was found to be an advantage; however, in small-scale farms of less than 0.5ha, direct payment contribution on farm household income was only 3%. In large-scale farms, 10ha or more, the contribution to farm income were found to be 29.4%. The income of large farms was 10 times larger than small farmers, and the direct payment entitlements that were received were 110 times larger. Through this policy, direct payments are required for future improvements and modifications.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.530-537
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• 2016

This study investigates frontal crashes, analyzes the driver's action related to the change of the collision direction and determines the severity of (bodily injury). This study was conducted from August, 2013, to January, 2014, and the data for the car damage and human body damage were collected by emergency medical teams. In terms of data collection, we collected the accident vehicle, crash direction, body damage, etc., based on the Korea In-depth Accident Study (KIDAS) and Injury Severity Score (ISS). We used Minitab 17 and SPSS 22.0 to do the frequency analysis and ANOVA. In the analysis results, the prevalence of frontal collisions was 55.8% and mostly occurred in the 12 o'clock direction. In the analysis of the frontal crash direction according to age, the average ages for the 11, 12 and 1 o'clock directions were $46.46{\pm}13.47$, $44.43{\pm}13.40$ and $52.46{\pm}12.04$, respectively, so the older age drivers had a high probability of the accident occurring in the 1 o'clock direction. In the analysis of men's frontal collision direction according to age, the average ages in the 11, 12 and 1 o'clock directions were $47.10{\pm}13.88$, $45.24{\pm}13.78$ and $55.73{\pm}13.38$, respectively, so older aged men had a high probability of having collisions in the 1 o'clock direction. However, the statistical analysis of the frontal crash direction according to age in women didn't show any meaningful trend. When comparing the ISS according to age of the men and women in the collision direction, the men were less likely to have a 12 o'clock collision when $ISS{\geq}9$ and more likely to have a 1 o'clock collision when ISS<9. As a result, frontal crashes are more likely to occur in the 12 o'clock direction and the ISS decreases because the likelihood of frontal crashes in the 1 o'clock direction increases with increasing age. Therefore, when men recognize that they are heading for a 12 o'clock direction collision, they try to steer to the left to reduce the body damage.

• Korean Security Journal
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• no.29
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• pp.139-162
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• 2011

The purpose of this study is to compare with the general and behavioral characteristics between simple and serial arsonists using the data derived from Scientific Crime Analysis System, Criminal Filing Search System, and Crime Information Management System. The analysis and findings reported here are derived from data extracted from 160 arsonists arrested by police officer. The independent variables included such socio-economic characteristic as arsonists' gender, age, occupation, education level, and previous criminal records of arsonists, and finally the general characteristics of the scene of fire settings. The dependent variable is whether or not serial fire setter. To achieve the purpose, the analysis of frequencies and cross-tab were conducted. According to frequence and cross-tab analysis, there are great differences of the general and behavior characteristics between two groups. In the comparison of simple and serial arsonists, serial arsonists are more likely to have previous criminal records, low socio-economic status, unmarried and no cohabitants than simple arsonists. furthermore, serial arsonists are more likely to use garbage papers for fire setting in the scene of the crime, to have mental or psychological problems, and to get involved in fire setting for the psychological pleasure than simple arsonists do. The present research has some obvious limitations. First, the analysis is based only on arsonists arrested by police officers. These may be considerable differences in arsonists arrested by police officers and fire setters not arrested by them. Additional research is needed to assess the extent to which these findings would apply to fire setters not arrested by police officer in Korea. Secondly, the data in this study are cross-sectional and simple cross-tab analysis are used. Potential limitation of cross-sectional data concerns the inability to specify the changes in measures as arsonists behavioral characteristics. Therefore, further studies need to use longitudinal data and more complicate statistical techniques such as correlation analysis, multiple regression analysis, or LISREL models to specify the casual relationships between dependent and independent variables for fire settings. Even if this study has some limitations, it is meaningful in which it first investigated the comparison of simple and serial arsonists focusing on the general and behavioral characteristics between two groups in Korea.

• 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 Technology Innovation
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• v.17 no.2
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• pp.1-23
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• 2009

The Survey on the Industrial Research and Development(R&D) is the primary source of information on R&D performed by Korea industrial sector. The results of the survey are used to assess trends in R&D expenditures. Government agencies, corporations, and research organizations use the data to investigate productivity determinants, formulate tax policy, and compare individual company performance with industry averages. Recently, Korea Industrial Technology Association(KOITA) has collected the data by complete enumeration. Koita has, currently, considered sample survey because the number of R&D institutions in industry has been dramatically increased. This study develops survey design for the industrial research and development(R&D) statistics by introducing a sample survey. Companies are divided into 8 groups according to the amount of R&D expenditures and firm size or type. We collect the sample from 24 or 8 sampling strata and compare the results with those of complete enumeration survey. The estimates from 24 sampling strata are not significantly different to the results of complete enumeration survey. We propose the survey design as follows: Companies are divided into 11 groups including the companies of which R&D expenditures are unknown. All large companies are included in the survey and medium and small companies are sampled from 70% and 3%. Simple random sampling (SRS) is applied to the small company partition since they show uniform distribution in R&D expenditures. The independent probability proportionate to size (PPS) sampling procedure may be applied to those companies identified as 'not R&D performers'. When respondents do not provide the requested information, estimates for the missing data are made using imputation algorithms. In the future study, new key variables should be developed in survey questionnaires.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.4
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• pp.317-324
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• 2015

GNSS was firstly proposed for application in weather forecasting in the mid-1980s. It has continued to demonstrate the practical uses in GNSS meteorology, and other relevant researches are currently being conducted. Precipitable Water Vapor (PWV), calculated based on the GNSS signal delays due to the troposphere of the Earth, represents the amount of the water vapor in the atmosphere, and it is therefore widely used in the analysis of various weather phenomena such as monitoring of weather conditions and climate change detection. In this study we calculated the PWV through the meteorological information from an Automatic Weather Station (AWS) as well as GNSS data processing of a Continuously Operating Reference Station (CORS) in order to analyze the heavy snowfall of the Ulsan area in early 2014. Song’s model was adopted for the weighted mean temperature model (T_m), which is the most important parameter in the calculation of PWV. The study period is a total of 56 days (February 2013 and 2014). The average PWV of February 2014 was determined to be 11.29 mm, which is 11.34% lower than that of the heavy snowfall period. The average PWV of February 2013 was determined to be 10.34 mm, which is 8.41% lower than that of not the heavy snowfall period. In addition, certain meteorological factors obtained from AWS were compared as well, resulting in a very low correlation of 0.29 with the saturated vapor pressure calculated using the empirical formula of Magnus. The behavioral pattern of PWV has a tendency to change depending on the precipitation type, specifically, snow or rain. It was identified that the PWV showed a sudden increase and a subsequent rapid drop about 6.5 hours before precipitation. It can be concluded that the pattern analysis of GNSS PWV is an effective method to analyze the precursor phenomenon of precipitation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.261-268
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• 2011

This study was carried out to determine the forage production and quality of Italian ryegrass (IRG) and forage barley developed by Korea in Suwon, 2009~'10. The nine treatments were two IRG varieties (Kowinearly with early maturity and Kowinmaster with medium maturity), five barley varieties (Youngyang, Wooho, Yuyeon, Dami and Youho), and two mixtures (Kowinearly + Yuyeon and Kowinmaster + Yuyeon). The heading dates of Kowinearly and Kowinmaster were 14 May and 18 May, respectively. The growth stage of barley investigated at 22 May were late milk in Youngyang and Wooho, early dough in Dami and early to medium dough in Yuyeon and Youho. Plant length of IRG in IRG + barley mixtures was 117~118 cm, which was longer than those of IRG monoculture of 98~101 cm, and no lodging was found in mixtures. The dry matter (DM) percentage at harvest was 20.7~25.4% in all treatments. The botanical composition of IRG in mixtures was 43.1%. The percentage of spike per barley plant was become high according to progressed maturity, as a 35.7%, 44.1%, 54.8% and 57.2% in late milk, dough, yellowish and full ripeness stage, respectively, and the spike percentages of Youngyang and Wooho were tends to high. The crude protein (CP) content of IRG as 9.0~10.0% was higher than that of barley (7.0~8.5%), and the contents of NDF and ADF of barley were lower than those of IRG, and in vitro DM digestibility were 64.4% in Kowinearly, 64.1% in Kowinmaster, 64.5% in mixture, and 60.2% (Youho) to 66.4% (Wooho) in barley. The yields of DM, CP and in vitro digestible DM were high in Kowinmaster+barley mixture as a 11,508 kg, 1,046 kg and 7,422 kg per ha, respectively (p<0.05). However, no significant differences in forage yield were observed among cultivar of IRG, and barley, although Wooho was tends to high in digestibility and forage yield among five barley varieties. In conclusion, the mixture cultivation of IRG Kowinmaster + forage barley was recommended, because of preventing of IRG lodging, higher plant length of IRG, increasing of forage yield, and stable production. Selection of suitable winter forage species and variety for district, climate environment, and utilization type of farm was also important.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.245-251
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• 2013

These experiments are being conducted to obtain data of plant height, panicle length, heading date, number of culm, and fresh and dry weight, crude protein, acid detergent fiber (ADF), neutral detergent fiber (NDF), total digestible nutrients (TDN) by six times seeding of 10 days interval ranging from May 1st to June 21st for two types of barnyard millet from the Suwon area in Korea. In the early-heading type, IT 170609 (Echinochloa crus-galli), the plant height and the number of culm per square meters are decreased by late seeding relatively, and heading date is 7 to 10 days earlier than the late seeding. And the dry weight of forage is rapidly decreased after the June 11th seeding. In the late-heading type, IT 195422 (Echinochloa frumentacea), the plant height and the number of culm per square meters are also decreased by late seeding relatively, and heading date is about 13 days earlier than late seeding. The dry weight of forage was rapidly decreased after the June 11th seeding. In both two types, the nutritive value of ADF, NDF, and TDN are not changed by late seeding, but crude protein is increased by late seeding. The TDN yields of late-heading type, IT 195400, show average amounts in the June 1st seeding, but the TDN yield of early-heading type, IT 170606, indicate safety amounts of dry weight to the March 21st seeding. And these data are available for cropping systems, cultivating barnyard millet in summer and cereals for forage in winter, to get high production of forage in Korea.