• The Journal of Korean Academy of Prosthodontics
• /
• v.56 no.3
• /
• pp.206-211
• /
• 2018

Purpose: Recently, a method of forming a slot in the prosthesis lingual has been introduced to solve the occlusal and aesthetic disadvantages of screw-retained prosthesis in the manufacture of implant-fixed prosthesis and to ensure retrievability in cement retained prostheses. The purpose of this study is to investigate the effect of the internal gap on the removal of the prosthesis in the preparation of cement-retained implant prostheses with lingual slots. Materials and methods: Titanium abutment and internal gap of the zirconia prosthesis to be attached to the upper part were set to 30, 35, and $50{\mu}m$, respectively. Three for each type total 15 were produced for each type. The zirconia prosthesis formed a retrievable cement-type slot with a space of 1 mm at the location where the titanium abutment meets the shelf area. Autocatalytic resin cement was used for bonding of abutment and zirconia prosthesis, and the maximum removal stress value was measured in units of Ncm by using the customized equipment of the cemented specimen. The Kruskal-Wallis test was used to compare the three groups by statistical analysis (${\alpha}=.05$), modified by post hoc test the Mann-Whitney U-test and the Bonferroni correction method were used to compare the two methods (${\alpha}=.017$). Results: There was no statistically significant difference in removal stress between the $30{\mu}m$ group and the $35{\mu}m$ group in the internal gap (P = .032), and there was a significant difference between the $30{\mu}m$ group and the $50{\mu}m$ group, between the $35{\mu}m$ group and the $50{\mu}m$ group (P < .017). Conclusion: Thus, the internal gap of computer-aided design affected the retention between the zirconia prosthesis and the titanium abutment.

• Child Health Nursing Research
• /
• v.19 no.2
• /
• pp.85-93
• /
• 2013

Purpose: The study purposes were to describe the process of developing the Korean versions of the Six Dimension Scale of Nursing Performance (Six-D) and Student Nurse Stress Index (SNSI) and psychometric evaluation of the two measurements. Methods: This was a methodology study using a descriptive cross-sectional design with 51 nursing students in 4th year of university. Internal consistency reliability was assessed using Cronbach alphas. Construct validity was determined by exploring correlations among Six-D, SNSI, objective structured clinical examination (OSCE), self-efficacy and grade point average (GPA). Results: Internal consistency reliability of Six-D and SNSI was acceptable with Cronbach's ${\alpha}$ of .95 and .82. Correlation analysis to determine construct validity revealed that Six-D presented positive correlations with OSCE (r=.109~.272) and self-efficacy (r=.005~.161) and negative correlation with GPA (r=-.246~-.394), although all were not statistically significant. SNSI presented all negative correlations with OSCE (r= -.007~-.238), self-efficacy (r=-.246~-.394), and GPA (r=-.092~-.426) and were mostly statistically significant except OSCE. Conclusion: Six-D needs more evidence to confirm validity to predict observed clinical competency and theoretical relationships with self-efficacy and GPA. However, SNSI presented trends of expected relationships with relevant variables. Therefore, further research is recommended in testing validity of Six-D with other student populations.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.46 no.6
• /
• pp.453-458
• /
• 2001

The Rural Development Administration (RDA) of Korea now operates a system called Rice Variety Selection Tests (RVST), which are now being implemented in eight Agricultural Research and Extension Services located in eight province RVST's objective is to provide accurate yield estimates and to select well-adapted varieties to each province. Systematic evaluation of entries included in RVST is a highly important task to select the best-adapted varieties to specific location and to observe the performance of entries across a wide range of test sites within a region. The rice yield data in RVST for ordinary transplanting in Kangwon province during 1997-2000 were analyzed. The experiments were carried out in three replications of a random complete block design with eleven entries across five locations. Additive Main effects and Multiplicative Interaction (AMMI) model was employed to examine the interaction between genotype and environment (G$\times$E) in the biplot form. It was found that genotype variability was as high as 66％, followed by G$\times$E interaction variability, 21％, and variability by environment, 13％. G$\times$E interaction was partitioned into two significant (P＜0.05) principal components. Pattern analysis was used for interpretation on G$\times$E interaction and adaptibility. Major determinants among the meteorological factors on G$\times$E matrix were canopy minimum temperature, minimum relative humidity, sunshine hours, precipitation and mean cloud amount. Odaebyeo, Obongbyeo and Jinbubyeo were relatively stable varieties in all the regions. Furthermore, the most adapted varieties in each region, in terms of productivity, were evaluated.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.5B
• /
• pp.595-601
• /
• 2008

The purpose of this study is to investigate the trends and patterns of various kind of water uses in a household by metering in Korea. Water use components are classified by toilet, washbowl, bathing, laundry, kitchen, miscellaneous. Flow meters are installed in 140 household selected by sampling in all around Korea. The data are gathered by web-based data collection system from the year 2002 to 2006, considering pre-investigated data such as occupation, revenue, family members, housing types, age, floor area, water saving devices, education, miscellaneous. Reliable data are selected by upper fence method for each observed water use component and statistical characteristics are estimated for each residential type to determine liter per capita per day. Estimated domestic per capita day show an indoor water use with the range from 150 lpcd to 169 lpcd for each housing type as the order of high rise apartment, multi-house, and single house. As the order of consuming amount among water use components, it is investigated that toilet (38.5 lpcd) is the first, and the second is laundry water (30.8 lpcd), the third is kitchen (28.4 lpcd), the fourth is bathtub (24.7 lpcd), the next is washbowl (15.4 lpcd). The results are compared with water uses in U.K. and U.S. As life style has been changed into western style, pattern of water use in Korea is tend to be similar with the U.S. water use pattern. Compared with the surveying results by Bradley, on 1985. Thirty liter of total use increased with the advancement of economic level, and a little change of water use pattern can be found. Especially, toilet water take almost half part of total water use and laundry water shows lowest as 11% in surveying at the year of 1985. But, this study shows that 39 liter, 28% of toilet water, has been decreased by the spread of saving devices and campaign. It is supposed that the spread large sized laundry machine make by-hand laundry has been decreased and water use increased. Unit water amount of each end-use in household can be applied to design factor for water and wastewater facilities, and it play a role as information in establishing water demand forecasting and conservation policy.

• Journal of Internet Computing and Services
• /
• v.25 no.4
• /
• pp.65-72
• /
• 2024

To faithfully represent the intention of the work in the exhibition space, lighting that provides high color reproduction like natural light is required. Thus, many lighting technologies have been introduced to improve CRI, but most of them only evaluated the general color rendering index (CRI Ra), which considers eight pastel colors. Natural light provides excellent color rendering performance for all colors, including red and blue, expressed by color rendering index of R9 and R12, but most artificial lighting has the problem that color rendering performance such as R9 and R12 is significantly lower than that of natural light. Recently, lighting technology that provides CRI at the level of natural light is required to realistically express the colors of works including primary colors but related research is very insufficient. Therefore this paper proposes exhibition hall lighting that fulfills CRI with a focus on CRI Ra, R9, and R12 based on the characteristics of natural light. First reinforcement wavelength bands for improving R9 and R12 are selected through analysis of the actual measurement SPD of natural and artificial lighting. Afterward virtual SPDs with a peak wavelength within the reinforcement wavelength band are created and then SPD combination conditions that satisfy CRI Ra≥95, R9, and R12≥90 are derived through combination simulation with a commercial LED light source. Through this, after specifying two types of light sources with 405,630nm peak wavelength that had the greatest impact on the improvement of R9 and R12, the exhibition hall lighting applied with two W/C White LEDs is designed and a control Index DB of the lighting is constructed. Afterward experiments with the proposed method showed that it was possible to achieve high CRI at the level of natural light with average CRI Ra 96.5, R9 96.2, and R12 94.0 under the conditions of illuminance (300-1,000 Lux) and color temperature (3,000-5,000K).

• Journal of the Korean Institute of Gas
• /
• v.22 no.5
• /
• pp.53-61
• /
• 2018

Low-salinity water based polymerflooding (LSPF) is one of promising enhanced oil recovery (EOR) method that has the synergetic effect of combining polymer injection method and low-salinity water injection method. In order to maximize EOR efficiency, it is essential to design low-salinity water appropriately considering the properties of polymer. In this aspect, the main purpose of this study is to investigate the effect of pH and $SO_4{^{2-}}$ ion which one of PDI (Potential Determining Ion) on oil production when applying LSPF to carbonate oil reservoir. First, the stability and adsorption of polymer molecule were analyzed in different pH of injection water and $SO_4{^{2-}}$ concentration in injection water. As a result, regardless of pH and $SO_4{^{2-}}$ concentration, when $SO_4{^{2-}}$ ion was contained in injection water, the stability of polymer solution was obtained. However, from the result of polymer retention analysis, in neutral state of injection water, since $SO_4{^{2-}}$ interfered the adsorption of polymer, the adsorption thickness of polymer was thinner as $SO_4{^{2-}}$ concentration was higher. On the other hand, when injection water was acidic as pH 4, the amount of polymer adsorption increased with the injection of polymer solution, so the mobility of polymer solution was greatly lowered. From the results of wettability alteration due to low-salinity water effect, in the case of neutral injection water injected, as $SO_4{^{2-}}$ concentration was increased, more oil which attached on rock surface was detached, altering wettability from oil-wet to water-wet. On the other hand, in acidic condition, due to complex effect of rock dissolution and polymer adsorption, wettability of the entire core system was less altered relatively to neutral condition. Therefore, it was evaluated that better EOR efficiency was obtained when injecting low-salinity water based polymer solution containing high concentration of $SO_4{^{2-}}$ with neutral condition, enhancing the oil production up to 12.3% compared to low-salinity water injection method.

• Korean Journal of Poultry Science
• /
• v.36 no.1
• /
• pp.39-45
• /
• 2009

This study was carried out to investigate the effect of dietary supplementation of Acanthopanax (A) senticosus and Eucommiaceae on the expression of lipogenic, myogenic and oxidative stress genes in broiler chickens. Birds were subjected (assigned) to one of the following 5 dietary treatments: control (CON), A. senticosus 0.5% (T1), 1.0% (T2), Eucommiaceae 0.5% (T3) and 1% (T4). Each treatment was replicated 8 times with 4 birds per replication, housed in 4 birds per cage. Birds were arranged according to randomized block design. Feeding trial was conducted from day 4 to 35th day of age. Liver and muscle tissues were collected for analysis. Broilers subjected to 1% A. senticosus had higher feed conversion ratio than the other treated birds whereas no significant differences were found in body weight, weight gain and feed intake. The gene expression levels of fatty acid synthase were not different among the treatments while the transcription factor $PPAR{\gamma}$ was highly expressed in Eucommiaceae but not in control and A. senticosus. The gene expression levels of myogenin were high in both A. senticosus and Eucommiaceae compared to control group. MyoD also showed high expression in treated groups furthermore, Eucommiaceae stimulated the expression of MyoD more than that of A. senticosus. The antioxidant gene expressions (SOD, CAT, SOD, GPX) generally were not much different among the treatments, however, SOD and GPX were stimulated in broilers consumed 1% Eucommiaceae diet. The result of this experiment showed that dietary supplementation of A. senticosus and Eucommiaceae in broiler may improve the antioxidant defence system through SOD and GPX without affect of growth performance in broilers.

• Korean Security Journal
• /
• no.36
• /
• pp.255-292
• /
• 2013

Burglary (also called breaking and entering and sometimes housebreaking) is a crime, the essence of which is illegal entry into a building for the purposes of committing an offence. It is one of the most common types of crime and also a serious issue for every society. A house that is left insecure is an accessible and attractive target for burglars and therefore burglary resistance test & certification system for doors and windows has been developed in many countries. This paper explores several advanced foreign burglary resistance test/certifcation cases (the British SBD, the Dutch KOMO SKH/SKG, the Japanese CP mark, the Australian Standard Certification) for security products and domestic test/certification systems for fire safety products as a comparative study so that any improvement points can be gained for South Korea in the field of security product performance. The comparative analysis results show that South Korea is far behind the security product certification system and needs a lot of improvement in the system by benchmarking foreign cases. The domestic test/certification systems for fire safety products also give some insights for burglary-related security products' performance certification system in Korea. Overall, the need for relevant rules and regulations, the establishment of standards regarding testing and certification, including certified security +hardware product in building security certification system, performance testing as well as production testing (i.e. quality management system evaluation), the basic competency of testers, incentive system for certified/high quality security products were suggested in order to make an optimal model for the security production performance testing and certification system in Korea.

• Journal of agricultural medicine and community health
• /
• v.35 no.3
• /
• pp.287-300
• /
• 2010

Objectives: We identified factors associated with any participation and with "good participation" (as assessed by frequency of attendance) in health promotion programs at a public health center in Korea. Methods: The subjects included 199 women who attended a baseline examination of health promotion programs during the first half of 2009. We collected data by structured interviews and physical examinations. Participation status was quantified by the frequency of attendance to the program. We classified the subjects as non-participants (0) and participants (1+ times), and as poor participants (0-29 times) and good participants (30+ times). Results: Of the 199 subjects, there were 57 (28.6%) non-participants, while 56 (28.1%) were classified as good participants. The factors that significantly affected participation status, as identified by univariate analysis, were personal factors (age, educational level, marital status, religion, living with someone, monthly income), environmental factors (method of access, accessibility of other facilities), body mass index, hypertension, perceived barriers to health, emotional salience, affectionate domain of social support, and depression. Multiple logistic regression analyses indicated that method of access was the most significant factor affecting participation in the health promotion program, and that the factors most highly associated with good participation were emotional salience, hypertension and body mass index. Conclusions: Our findings suggest that specific factors determine and enhance participation in health promotion programs offered by public health centers. These factors should be considered during the design and evaluation of health promotion programs that are offered by public health centers.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.33 no.12
• /
• pp.1897-1909
• /
• 2009

This large-scale research project contributes to the theory development in the importance of clothing to the self and in the way that older persons might age successfully by fulfilling the need for self-actualization by incorporating a primary resource environment, such as clothing into their self-system. This paper presents one research objective from a lager project that explores the correlations among the Proximity of Clothing to Self (PCS), age identity (subjective or perceived age), and self-actualization (the highest level of human needs). A mail survey design was applied to this study. In November 2004, two questionnaires, Clothing: A Resource for Successful Aging? (to measure PCS, age identity, and demographic variables) and Personal Orientation Inventory (to measure self-actualization), were sent to 1,700 older persons in the U.S. and 195 completed usable questionnaires were returned (12% response rate). This research discovered that the age identity of older persons did not relate with PCS except for those 85 years and over. There were negative correlations among subscales of PCS and self-actualization. This result can be interpreted as that an older person who has not met the highest level of needs yet, can use clothing as a facilitator or need satisfier to meet a higher level of Self-Actualization (SA). Correlation analyses also revealed that older persons in the age category of 75 to 84 years were different from those in the category of 65 to 74 years and 85 years and over. This result implies that older persons in this age category are undergoing more psychological transitions than those in other categories. Further research is necessary to explore the relationship of several SA subscales with various clothing variables such as clothing interest, clothing involvement, or clothing satisfaction.