• Industry Promotion Research
• /
• v.4 no.2
• /
• pp.1-8
• /
• 2019

This research is a technology for cutting the insulation of the busbar (busbar) installed in the distribution panel or switchboard, the results of the study, first, the cutting unit and frame of the cutting unit including a housing attached to the upper and lower cutters, respectively Busbar coating laser cutting machine is installed on the top, characterized by consisting of a stopper for adjusting the coating cutting distance of the busbar. Second, the frame is installed with the guide bar in the longitudinal direction at the top so as to be located at the rear side end of the table, the post is installed vertically at the front and rear at the upper middle part, respectively, and cut to the table at the outer side of the front post. It is characterized by the formation of holes. Third, the supporter is fixedly installed on the upper part of the guide bar arranged in the frame, and is characterized by consisting of a cylinder and a support plate. The meaning of this study is to prevent the safety accidents of workers, to improve the efficiency of cutting work, and to prevent the occurrence of scratches on the surface of the busbar.

• Korean journal of communication and information
• /
• v.80
• /
• pp.115-142
• /
• 2016

This study aims to reveal the content of and logic behind a recent negative public sentiment toward female idols with the example of a debate over songstress IU's fourth album that was released late last year. While previous studies on fandom have focused on the identification process towards entertainers and making community, a recent phenomenon of "anti-fandom" or "malicious comments" implies that more research is needed on negative emotions such as hostility or schadenfreude (feelings of pleasure from others' misfortunes). Schadenfreude is a social sentiment that originated in modern liberalism, which features contradictions between public equality and private ownership, and that has been intensified in neoliberalism, which features a maximization of this contradiction centering on a meritocracy. Celebrities in Korea often become the targets of schadenfreude, which is associated with the suspicion that they gain popularity not from their abilities but from "just being popular." It should also be noted that this kind of schadenfreude operates differently between male and female entertainers. Specifically, the acquisition of money and fame by modern women whose presence used to be located in the private possessions of males is considered to be due to their unjustified use of sexuality. This is also the background of the recent online misogyny culture in Korea. In this context, IU, who had been successful at building a differentiated image of "sister-like idol artist," became a valid target. Although accusing IU of utilizing pedophilia reflects a stalemate that a current politics of sexual violence faces, it rather damages the name of an individual than attracts public attention to the structural causes of childsexualabuse. This is why I see the way that pedophilia was used in the debate over IU as a schadenfreude. Consequently, the term pedophilia here contributes to an expansion of the entertainment economy that is sustained by rises and falls of the celebrities' stock prices.

• Journal of dental hygiene science
• /
• v.17 no.4
• /
• pp.358-367
• /
• 2017

The purpose of this study was to evaluate the influence of water infiltration and flexural strength changes in dental porcelain with glazing treatment. The block specimens were prepared as experimental materials, using feldspar type commercial dental porcelain; then, these were fired at $940^{\circ}C$ for 1 minute. The fired specimens were polished with a dimension of $40{\times}5.5{\times}5mm$. The specimens were distributed to two experimental groups: with and without glazing treatment specimens (n=5), and they were immersed in a solution of pH 7 for 3, 7, and 20 days at $40^{\circ}C$ after fabrication. To evaluate the flexural strength changes with water infiltration treatment in specimens with and without glazing, the 3-point flexural test was performed, using a universal testing machine until failure occurred. Starting powder and fired specimens consisted of amorphous and leucite crystalline phase. The Vickers hardness of fired specimens was more than 1.6 times higher than that of the enamel of natural teeth. According to porosimeter results, the specimens without glazing treatment exhibited a porosity of about 14.7%, whereas the glazed specimens exhibited the lowest porosity at about 1.1%. The average flexural strength of glazed specimens was higher than the flexural strength of specimens without glazing treatment (p<0.05). The flexural strength of all specimens with and without glazing treatment deteriorated with accelerated aging in the solution. In addition, significant differences between these two treatment groups were observed in all of the specimens treated at various water infiltration periods (p<0.05). The exposure of internal pores and micro-cracks in the surface due to polishing of the fired specimens influenced mechanical behaviors. Especially, the flexural strength in specimens without glazing treatment has shown significant degradation with the infiltration of water. Therefore, this study suggests that glazing processes can improve mechanical properties of dental porcelain.

• Journal of Korean Society of Forest Science
• /
• v.102 no.1
• /
• pp.7-14
• /
• 2013

This study investigated the optimum condition of abrasion peeling machine and pellicle peeling ability of chestnut (Castanea spp.) varieties for the efficient production of peeled chestnuts. The optimum conditions were 50 minutes peeling time and 27 rpm of drum rotation speed and chestnut pellicle peeling ratio was 89.3%. Among 8 Korean chestnut varieties which were peeled under the optimum condition (27 rpm/50 min), 'Tsukuba (89.3%)', 'Tanzawa (72.2%)' and 'Ishizuchi (70.9%)' showed the highest ratio of pellicle peeling ratio. 'Tsukuba' had the most excellent peeled (grade I) chestnuts (77.3%), followed by 'Ishizuchi (46.7%)', and 'Tanzawa (45.0%)'. Regarding the chestnuts quality for commercialization, 'Tsukuba' had the most excellent peeled chestnuts (90.5%), followed by 'Tanzawa (74.8%)', and 'Ishizuchi (74.3%)'. 'Mipung (37.2%)' had the most broken and injured chestnuts and 'Tsukuba (5.9%)' had the least broken and injured chestnuts. Therefore this study concluded that 'Tsukuba' was the superior variety for producing high value-added processed chestnuts.

• Korean Journal of Food Science and Technology
• /
• v.44 no.6
• /
• pp.722-727
• /
• 2012

In order to improve the physical properties of brown rice by hydration and cooking, the amount of water absorption, hardness, reducing sugar, and minerals were measured for rice (NR), brown rice (NBR), and scratched brown rice (SBR). The amounts of water absorption were present in the order of NBR<0.07 SBR<0.20 SBR=NR after 210 min. The moisture contents of gelatinization rice were significantly different by degree of milling and scratch. The hardness of gelatinization rice were present in the order of NR<0.20 SBR<0.07 SBR

• The korean journal of orthodontics
• /
• v.25 no.2 s.49
• /
• pp.223-233
• /
• 1995

The purpose of this study was to evaluate the effects of surface conditioning with $10\%$ polyacrylic acid, etching with $38\%$ phosphoric acid, and polishing with a slurry of pumice on shear bond strengths of light-cured glass ionomer cement, chemically cured glass ionomer cement, and a composite resin to enamel, and to observe the failure patterns of bracket bondings. Shear bond strengths of glass ionomer cements were compared with that of a composite resin. Metal brackets were bonded on the extracted human bicuspids after enamel surface treatments, and samples were immersed in the $37^{\circ}C$ distilled water bath, and shear bond strengths of glass ionomer cements and a composite resin were measured on the Instron machine after 24hrs passed, and the deboned samples were measured in respect of adhesive remnant index. Scanning electron micrographs were taken of enamel surfaces after various treatments. The data were evaluated and tested by ANOVA and Duncan's multiple range test, and those results were as follows. 1. Shear bond strength of light-cured glass ionomer cement showed statistically higher than that of chemically cured glass ionomer cement. 2. Shear bond strengths of light-cured and chemically cured glass ionomer cements to enamel treated with $10\%$ polyacrylic acid and $38\%$ phosphoric acid showed statistically higher than those with a slurry of pumice. 3. According to scanning electron micrographs, enamel surface conditioned with $10\%$ polyacrylic acid is slightly etched and cleaned, that etched with $38\%$ phosphoric acid is severely etched, and that polished with a slurry of pumice is irregulary scretched and not completely cleaned. 4. After debonding, light-cured glass ionomer cement to enamel treated with $10\%$ polyacrylic acid showed less residual materials on the enamel solace than composite resin to enamel etched with $38\%$ phosphoric acid. 5. There was no significant difference in the shear bond strength of light-cured glass ionomer cement to enamel treated with $10\%$ polyacrylic acid and that of composite resin to enamel etched with $38\%$ Phosphoric acid.

• Journal of Korean Ophthalmic Optics Society
• /
• v.7 no.1
• /
• pp.39-43
• /
• 2002

This study was investigated the anti-angiogenic activities of Cnidium officinale Makino and Tabanus bovinus by using Chorioallantoic membrane (CAM) and rat cornea. First experiment, the fertilized chicken eggs were kept in a humidified egg incubator at $37^{\circ}C$. After 4 days incubation, about 3 ml of albumin was aspirated from eggs with an hypodermic needles through a small hole drilled at the narrow end of the eggs, and the shell membrane on the floor of the air sac was peeled away. Embryos with chorioallantois of 3~5 mm in diameter were employed for the assay of antiangiogenic activity. Retinoic acid was used as a positive control for this experiment. After 48 h of treatment. branching pattern of blood vessels below coverslip containing retinoic acid ($10{\mu}g/egg$) was dramatically decreased. A simiar angiogenic inhibition was observed in the CAM treated with $50{\mu}g/egg$ of Cnidium omcinale Makino and Tabanus bovinus extracts. Second experiment, rat corneal neovascularization was induced by suturing (one stitch) the cornea with 10-0 nylon, and terramycin was applied on the cornea for I week to prevent corneal inflammation. In the cornea of rats untreated with herbal extracts, numerous vessels were usually seen invading the cornea by day 2 or 3 after suture, and reaching the lesion area within 5~6 days. Corneal neovascularization was gradually increased and peaked at 3 weeks. In contrast to this, herbal extracts conspicuously inhibited the angiogenesis, Oral administration of herbal extracts (20 mg/kg body weight/day) for 4 weeks significantly inhibited the rat corneal angiogenesis induced by suture, and the length of blood vessels in herbal medicine-treated rat cornea was conspicuously lower than that in control animals. A similar phenomenon was also observed in the rat cornea treated with thalidomide (200 mg/kg body weight/day). These findings indicate the anti-angiogenic properties of Cnidium officinale Makino and Tabanus bovinus, suggesting that these properties may be one of the pharmacological mechanisms underlying the anti-tumor and anti-metastatic activities of herbal extracts tested in this study.

• Korean journal of applied entomology
• /
• v.24 no.4 s.65
• /
• pp.195-201
• /
• 1986

This study was conducted to investigate the life history of Compsidia populnea which is major species of the stem-borers on Populus alba{\times}glandulosa$. Peak emergence of the adult of Compsidia populnea L. was around 10th${\sim}$l2nd of May in Chuncheon vicinities, having one generation a year in Korea. There was a preovipositional period of 10.7 days and a ovipositional period of 14.3.days. Mean adult longevity was 11 days for male and 13.8 days for female. Individual eggs were long oval with somewhat narrowed tip at one side and soft, 2.6mm in length, 0.8mm in diameter, and were laid singly under the U-shaped scars which were made by female before oviposition. Total number of scars per female averaged 56.6 ($8{\sim}135$) and eggs were found in 67.9 percent of the total scars. Egg period was $8{\sim}11$ days at $25^{\circ}C$ constant temperature and $7{\sim}14$ days in the field condition. Early young larvae stayed for $2{\sim}3$ weeks under the scars and then boring into the xylem, forming galls at this time. Size of the gall was 1.8cm($1.3{\sim}2.5$) in length, 1.6cm($1.0{\sim}2.2$) in diameter and the length of mine was everage 3.1cm. Fully grown larvae were developed around the early October and overwintered in the mines of galls. Pupation was done around the early of April. Pupal developmental period averaged 11 days($9{\sim}13$ days) at $25^{\circ}C$ constant temperature condition.

• Journal of Korean Ophthalmic Optics Society
• /
• v.16 no.3
• /
• pp.229-235
• /
• 2011

Purpose: The present study was performed to evaluate the safety of ophthalmic lenses in domestic market since eyeglasses wearers could be exposed to the negligent accident by damaged ophthalmic lenses. Method: Totally, 160 ophthalmic lenses (NK55, ${n_{d}}$ = 1.56) with the refractive powers of -3D, -6D, +3D, +6D manufactured by 4 companies in domestic market were evaluated using drop ball test. In accordance with FDA standard, steel ball (~16 g) was freely dropped on these ophthalmic lenses from 127 cm high and the surfaces of lenses were observed. Results: From the study, center thicknesses of NK55 ophthalmic lenses manufactured by 4 different companies showed somewhat different numbers even though the lenses had the same refractive index and powers. All convex lenses of +3D, +6D were evaluated as the safe lenses since there was no damage such as crack and broken found on the lens surfaces after drop ball testing. However, some noticeable broken was shown on the surfaces of concave lenses with relatively thinner center thickness. Especially, 59(73.8%) of total 80 concave lenses with the refractive power of -3D and -6D classified as unacceptable lenses to FDA standard. Conclusions: From the results, the negligent accident by damaged ophthalmic lenses should be considered as well as the correction of visual acuity, design and price when customers purchase eyeglasses. Thus, the enforcement regulation like drop ball testing of uncut ophthalmic lens could be suggested to guarantee the safety of ophthalmic lenses in domestic market.