• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.3
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• pp.133-137
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• 2007

Ecological lightweight aggregates were made in order to recycle the dredged soils from the seaside construction area and the bottom ashes from the power plant. Various physical and chemical analysis were performed on them to identify their possibility for applying lightweight concrete fields. Lightweight aggregates were made of bottom ashes and dredged soils from Yongheung Island which is located 20km west away from Seoul, and all the raw materials were milled before mixing. The physical and chemical properties such as density, absorption rate, stability, alkali latency reaction, heavy metal leaching of the lightweight aggregates were tested and analysed by following the KS standard procedures. From the size analysis, the coarse aggregates showed a suitable fit on standard particle ranges; however, the fine aggregates showed a large deviation from the standard. The absorption rates were increased with decreasing weight of the aggregates. All the aggregates were turned out to be safe by the stability and heavy metal leaching test; however, some of the aggregates were confirmed on the border of harmless and possibly harmful region through the alkali latency reactivity test.

• The Journal of Advanced Prosthodontics
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• v.9 no.6
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• pp.463-469
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• 2017

PURPOSE. To evaluate the fit of a three-unit metal framework of fixed dental prostheses made by subtractive and additive manufacturing. MATERIALS AND METHODS. One master model of metal was fabricated. Twenty silicone impressions were made on the master die, working die of 10 poured with Type 4 stone, and working die of 10 made of scannable stone. Ten three-unit wax frameworks were fabricated by wax-up from Type IV working die. Stereolithography files of 10 three-unit frameworks were obtained using a model scanner and three-dimensional design software on a scannable working die. The three-unit wax framework was fabricated using subtractive manufacturing (SM) by applying the prepared stereolithography file, and the resin framework was fabricated by additive manufacturing (AM); both used metal alloy castings for metal frameworks. Marginal and internal gap were measured using silicone replica technique and digital microscope. Measurement data were analyzed by Kruskal-Wallis H test and Mann-Whitney U-test (${\alpha}=.05$). RESULTS. The lowest and highest gaps between premolar and molar margins were in the SM group and the AM group, respectively. There was a statistically significant difference in the marginal gap among the 3 groups (P<.001). In the marginal area where pontic was present, the largest gap was $149.39{\pm}42.30{\mu}m$ in the AM group, and the lowest gap was $24.40{\pm}11.92{\mu}m$ in the SM group. CONCLUSION. Three-unit metal frameworks made by subtractive manufacturing are clinically applicable. However, additive manufacturing requires more research to be applied clinically.

• Journal of Digital Convergence
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• v.13 no.4
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• pp.235-246
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• 2015

Understanding the various unspecified hacking and repeated cyber DDoS attacks, finally was able to find a solution in the methods of attacks. Freely researching approach that combines the attacker and defender, offensive and defensive techniques can be called a challenge to discover the potential in whimsy. In this paper we test and evaluate "KWON-GA", global white hackers team has made by many years of experiences in infiltration and diagnosis under guise of offence is the best defence. And it is knowledge information ICT Convergence security solution which is developed for the purpose of defence, it provide customization policy that can be fit to customer's system environment with needed techniques and it is processed with unique proprietary technology so that it's not possible to scan. And even if it has leaked internally it's impossible to analyze so hackers can't analyze vulnerability, also it can't be abused as hacking tools.

• Korean Journal of Human Ecology
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• v.7 no.3
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• pp.5-13
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• 2004

This study was performed to investigate the characteristics of denim pants preferred by Korean women in their 20's through the analysis of the sensory test(appearance) and garment space length. Four kinds of ready-made denim pants of national and licensed brand on sale in Korea were used as the experimental garment. The results were as follows: 1. The significant difference among brands were found in the appropriateness of ease in the part of waist belt(front), knee (front), ankle(back) and the total silhouette. 2. In the analysis of garment space length. the significant difference among brands was shown in waist belt part $(FL60^{\circ})$, hip $(FL0^{\circ},\;FL30^{\circ})$, crotch(SRR) and knee(BR60^{\circ}). However, total average was not significant difference. 3. According to analysis of pattern size, the brand N was out of balance in crotch depth and girth. by which it can be said that N got the lowest score in sensory test (appearance). On the other hand, Brand GU was large in circumference with short crotch length. 4. Therefore, the most preferred denim pants pattern of Korean women in their 20's was fit in waist belt. hip. crotch circumference and a little bit tight in crotch depth and length. As the design was limited as straight style. more design and brands must be included for future study.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.8
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• pp.933-945
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• 2011

This research proposes a pattern design method for 24 pleated skirts in order to develop an automatic draft program for pleated skirts that will enhance fit and enable mass production. The research method and results are outlined as follow. 1. Three-dimensional body measurements were conducted on 30 randomly selected women in their 20s. By using 34 body measurement items and 6 types of calculations among the items, the items required in the designing of an original pleated skirt were extracted. They were then interpreted through correlation analysis, variance analysis, a t-test, linear regression analysis and multiple regression analysis. 2. An extra amount was added to the waist measurement and external capsule measurement according to the number of times the pleats coincided and the thickness of the fabric by the degree of polymerization of the horizontal cross section (the test of this research: 0.518mm). The extra amount of waist measurement was 3.6cm while the hip measurement was 4.3cm larger than the hip measurement combined with the external capsule measurement and the extra amount. 3. Based on the ${\pm}$standard deviation/2 as the average of the difference between the external capsule measurement and waist measurement, the subjects were classified into 3 somatotypes. Somatotype 1 presented an average total length of waist darts of 23.6cm while that of somatotype 2 was 26.2cm and that of somatotype 3 was 30.2cm. It has been confirmed that there is a significant difference among somatotypes in the total length of waist darts from the front center to the front side and the total length of waist darts from the side to the back center in terms of the average amount of waist darts for every 12 parts on the WL.

• Journal of Preventive Medicine and Public Health
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• v.20 no.1 s.21
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• pp.67-83
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• 1987

This study relates to the problems of organizational performance in the Christian hospitals. In this study, quality of working life (QOWL), which harmonizes individual as well as organizational goals, was used as an indicator of organizational performance from the open systems view. In order to identify the behavioral factors influencing QOWL in hospitals, self-administered questionnaires were distributed to 1,926 employees who were randomly selected from fifteen Christian hospitals from August 1 to August 30, 1986. The following results were obtained: 1) All correlation coefficients between QOWL and behavioral variables were statistically significant even though their magnitude varied according to hospital size. 2) Using factor analysis, 32 variables were parsimoniously grouped into four factors: individual conflicts, group behavior, organizational characteristics and situation, and job characteristics. The proportion of variance explained by these factors ranged from 33.5% to 38.6% according to hospital size. 3) The overall effects of the four factors in the multiple logistic models ranged from 0.85 to 3.12 according to hospital size. Among three hospital models, the model for small hospitals showed the best statistical fit. 4) The most influential factor was organizational characteristics and situation with an odds ratio ranging from 1.99 to 3.02. Again, the odds ratio was the highest for small hospitals. 5) For large hospitals, the two main factor effects were statistically significant: organizational characteristics and situation, and job characteristics. For medium hospitals, all main factor effects except job characteristics were statistically significant. For small hospitals, all main factor effects except group behavior were statistically significant. However, a factor interaction effect was shown only for large hospitals where it was statistically significant. 6) To examine whether the four factors influence financial performance, the four factor scores from the two financial performance groups were compared using Mann-Whitney test. The test results showed that the organizational characteristics and situation factor score was significantly different only for small hospitals.

• Journal of the Korean Geotechnical Society
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• v.20 no.4
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• pp.29-38
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• 2004

A finite element nonlinear stress-deformation model with multi-interface element is applied to the stability analysis of waste landfill slope. Strength parameters of waste and geosynthetic materials are obtained from the triaxial test of waste and the direct shear test of geosynthetics, respectively. The landfill models used for the numerical models are fit to regulations of the Korean waste management law. The results of the strength tests showed linear behavior for the waste and nonlinear behavior for the eosynthectic materials. The stability analysis with multi-interface element for the geosynthetic materials in the liner system showed large shear stress and slippage at the boundary of the foundation and the slope of the waste fill. This analysis verified the necessity of multi-interface analysis for waste landfills with composite liners.

• The Journal of Advanced Prosthodontics
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• v.3 no.3
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• pp.119-125
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• 2011

PURPOSE. The aim of this study was to evaluate the influence of resin cement thickness on the microtensile bond strength between zirconium-oxide ceramic and resin cement. MATERIALS AND METHODS. Thirty-two freshly extracted molars were transversely sectioned at the deep dentin level and bonded to air-abraded zirconium oxide ceramic disks. The specimens were divided into 8 groups based on the experimental conditions (cement type: Rely X UniCem or Panavia F 2.0, cement thickness: 40 or 160 ${\mu}m$, storage: thermocycled or not). They were cut into microbeams and stored in $37^{\circ}C$ distilled water for 24 h. Microbeams of non-thermocycled specimens were submitted to a microtensile test, whereas those of thermocycled groups were thermally cycled for 18,000 times immediately before the microtensile test. Three-way ANOVA and Sheffe's post hoc tests were used for statistical analysis (${\alpha}$=95%). RESULTS. All failures occurred at the resin-zirconia interface. Thermocycled groups showed lower microtensile bond strength than non-thermocycled groups (P<.001). Differences in cement thickness did not influence the resin-zirconia microtensile bond strength given the same resin cement or storage conditions (P>.05). The number of adhesive failures increased after thermocycling in all experimental conditions. No cohesive failure was observed in any experimental group. CONCLUSION. When resin cements of adhesive monomers are applied over air-abraded zirconia restorations, the degree of fit does not influence the resin-zirconia microtensile bond strength.

• Journal of the Korean Home Economics Association
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• v.43 no.8 s.210
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• pp.69-81
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• 2005

The purpose of this study is to design high school boy's uniforms, which fit well and express the traditional aesthetics of Korean clothing. Korean traditional clothing is getting ground for the use as active wear as well as formal wear such as wedding or special holiday clothing. This is partly due to the introduction of western clothing in Korea because of the practical nature of this type of clothing. This study was carried out as follows: 1. First, 197 high school boys from 5 different high schools were surveyed. All of these schools use Korean style school uniforms. The survey asked the students about their satisfaction with the current designs, problems and design preferences for Korean style high school uniforms. In general, the boys are not satisfied with the aesthetic and fashionable aspects of their uniforms. 2. The second survey dealt with design preferences from a variety of design options of Korean-style school uniforms. The design options were presented to the students as in the form of 10 different types jackets and 6 different types of pants. Using the results of the second survey as a guideline, the designs of Korean style school uniforms were developed. 3. In order to make the test garments, a block bodice pattern for the Korean style school uniforms was developed. Using the developed bodice block pattern, 6 designs were made of wool. The 6 test designs consisted of 3 different types of jackets and 3 different types of pants. 4. Incorporating the most preferred design features, school boy Korean style school uniform designs were developed. The characteristics of the design include neck line opening and its finishing, AH and sleeve shape, embroidered traditional patterns and fastenings. In this study we were able to develop comfortable clothing, which expressed the traditional aesthetics of Korean clothing.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.4
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• pp.527-536
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• 2015

Purpose: In this paper, we have dealt with problems and improvement of korean optician system. Methods: Using the relevant material of korean optician system and international optometrist system, provides the theoretical basis of the need for regulatory changes optician. Results: The people with refractive errors are increasing, 67% of refractive error test is made from optical shop and korean optician are sufficient trained, many opticians are in charge of the refractive error test at the ophthalmic hospital. We have confirmed that current law does not reflect adequately the nature of optician's work. Conclusions: Since current capacity of the Korean opticians and education system ready to provide health services for people, therefore an korean optician must redefine the law to fit the reality.