• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.3
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• pp.221-231
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• 2005

In this study, occupational exposures to man-made mineral fibers (MMMFs) including glass wool, rock wool, and continuous glass filament fibers were determined and evaluated on the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV). A total of 171 personal samples collected from 4 glass wool fiber, 2 rock wool fibers, 4 continuous filament glass fiber products manufacturing and a glass fiber and rock wool insulations using industries, and determined respirable fibers concentrations using the National Institute for Occupational Safety and Health (NIOSH) Method 7400, "B counting rule. The fiber concentrations of samples from workers installing thermal insulations in a MMMF using industry showed the highest value: geometric mean (GM) = 0.73 f/cc and maximum = 2.9 f/cc, 70% of them were above the TLV, 1 f/cc. Workers' exposure level (GM= 0.032 f/cc) in the rock wool manufacturing industries was significantly higher than those of glass wool (GM=0.012 f/cc) and continuous filament glass fibers (GM=0.010 f/cc) manufacturing industries (p<0.01). No samples were more than the TLV in the MMMF manufacturing industries. There was a significant difference among companies in airborne fiber levels.

• Journal of the Korea Concrete Institute
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• v.14 no.3
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• pp.440-448
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• 2002

Waste glass has been increased with the development of industry. The utilization of waste glass for concrete can cause the concrete to be cracked and to be weakened due to an expansion by alkali-silica reaction(ASR). In this study, ASR expansion and properties of strength were analyzed in terms of waste glass color(amber, emerald-green), industrial by-products(ground granulated blast-furnace slag, fly ash), and the content of industrial by-products for reducing ASR expansion caused by the waste glass. The possibility of using glass ground as pozzolanic properties was also analyzed. From the result of this study, the pessimum size of waste glass was 2.5∼1.2 mm regardless of waste glass color. And the smaller than 2.5∼1.2 mm waste glass is, the more decreasing expansion of ASR is. Also, the combination of waste glass with industrial by-products have an effect on reducing the expansion and strength loss caused by ASR between the alkali in the cement paste and the silica in the waste glass, and the glass ground of less than 0.075 mm is applicable as a pozzolanic material.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.167-172
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• 2002

Recent years, optical components'are widely used in optical communication industry for high speed and mass storage data processing. Micro grooving of planar lightwave circuit and glass, those are widely used in optical component, are realized by polycrystalline diamond tool with ultrasonic vibration. To know the characteristics of brittle materials cutting, ultrasonic vibration cutting tool and machining system are built for the experiment. Grooving on planar lightwave circuit and glass experiments are performed and their shape are measured by photograph with microscope. It reveals that better groove shape with low chipping of planar lightwave circuit and glass are obtained by micro grooving machining with ultrasonic vibration. These experiments are considered as a possibility to the micro grooving of optical communication components.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.222-223
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• 2017

In the automotive industry, such as scrap metal and plastic scrap process is being recycled. Although the glass beads are used as road paving or other additives and processing crushing, recycling is known that there are limits. The utilization of waste glass was evaluated as a concrete admixture by using powder characteristics and chemical composition of the glass. As a result of using waste-glass powder as an admixture, it is difficult to expect the pozzolanic effect, but it is found that it can increase the fluidity of concrete and ensure the durability performance in the appropriate amount range.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.6
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• pp.440-444
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• 2016

Owing to the introduction of various IT devices with emphasis on portability and design, the TFT (thin film transistor liquid crystal display) panel applied to IT devices has the same shape as the product, and the portability requirement of IT devices has resulted in a need for panels with higher rigidity. In this study, the effect of grinding conditions such as the feed rate and edge speed of edge grinding on the surface roughness and chipping of the machined surface is investigated using a metal bond wheel. During edge grinding of alkari-free glass, weak mechanical property of glass results in big chipping owing to generation of tensile stress at the end of grining operation. The results of this study show that the grinding characteristics of alkali-free glass are obtained and meet industry requirements.

• Review of Culture and Economy
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• v.21 no.2
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• pp.3-28
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• 2018

This study focuses on analyzing the glass ceiling effect in arts and culture professionals through the quintile decomposition applied to the RIF unconditional quantile regression and Oaxaca-Blinder decomposition technique. From the industrial viewpoint, we divide arts and culture professionals into cultural contents professionals(large category J industry) and arts professionals(large category R industry). For our analysis, we employ the pooling data of 'Wage Structure Survey' from 2009 to 2016. Our results are summarized as follows. First, as OLS wage decomposition showed that the gender wage gap among the arts professionals was lower than cultural contents professionals, but the discrimination portion of total gender wage gap was larger. Second, from quintile regression decompositions, the glass ceiling effects of two types of professionals showed different results. Cultural contents sector was observed with the "steady glass ceiling effect" as the portion of the discrimination was continuously increased, while the arts sector was observed with the "limited glass ceiling effect" as the discrimination had drastically increased in the 80s and 90s.

• Safety and Health at Work
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• v.11 no.4
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• pp.450-457
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• 2020

Background: The production of glass beads in Ghana is greatly impacted by the ingenuity of Ghanaian women. Preliminary investigations revealed the lack of interest on the part of women due to poor working conditions as a result of the influence of culture-specific silence. Therefore, the study investigated the poor working conditions faced by these industrious women with the ultimate goal of suggesting ways they can be empowered. Methods: A phenomenological study was conducted in two indigenous glass bead communities in Ghana. Data were solicited via direct observations, personal interviews and focus group discussions. Twenty-six purposively sampled respondents were recruited for the study. Data from the study were analyzed using Interpretative Phenomenological Analysis. Results: The results confirmed that the elderly women glass bead makers are much influenced by the Ghanaian culture of silence. This prevents the women from speaking about the challenges they are facing in their work. Also, the women are silenced because of the fear of losing their jobs as well as the reluctance of their male managers to remedy the challenges they encounter in the course of work. This has resulted in poor remuneration, lack of insurance packages for workers, certification, and absence of personal protective tools for the women. Conclusion: The study tasks the government of Ghana, the Legal Advocacy for Women in Africa (LAWA), the Fair Wages and Salaries Commission in Ghana, the Ghana Trade Union as well as the Local Government Workers' Union to empower the women to sustain the glass bead industry in Ghana.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.11 no.1
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• pp.25-32
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• 2005

This study was conducted in 2005 to investigate the current status of total packaging industries in Korea. The trends in development of the packaging industry were observed and interpreted as several factors such as the number of packaging industries, the number of employee in packaging industries, size, employee salary, and locations of packaging industry. The number of companies showed the increase of 6.3% per year until 2002 compared to 2175 companies at packaging industry in 1991. Based on the data of the number of companies to produce packaging materials, the packaging companies for plastic, metal, and wood were rapidly increased up to over 9%, whereas the glass and paper companies were only increased in 2%. The number of paper, plastic, wood, and packaging machine companies located at Seoul in 2002 was showed the great reduction, except to glass company compared to the number of the packaging industries in 1993 according to location of the company. Value added per employee in total packaging material industries were showed about 53-thousand dollars in 2002. These values were showed about 64.5% for total manufacture industries and increased to 8.1% from 1991 to 2002.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.2 s.179
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• pp.146-153
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• 2006

Acceleration sensors have widely been used in the various fields of industry. In recent years, micromachining accelerometers have been developed and commercialized by the micromachining technique or MEMS technique. Typical structure of such sensors consist of a cantilever beam and a vibrating mass fabricated on Si wafers using etching. This study investigates the feasibility of powder blasting technique for microfabrication of sensor structures made of the pyrex glass alternating the existing Si based acceleration sensor. First, as preliminary experiment, effect of blasting pressure, mass flow rate of abrasive and no. of nozzle scanning on erosion depth of pyrex and soda lime glass is studied. Then the optimal blasting conditions are chosen for pyrex sensor. Structure dimensions of designed glass sensor are 2.9mm and 0.7mm for the cantilever beam length and width and 1.7mm for the side of square mass. Mask material is from aluminium sheet of 0.5mm in thickness. Machining results showed that tolerance errors of basic dimensions of glass sensor ranged from 3um in minimum to 20um in maximum. This results imply the powder blasting can be applied for micromachining of glass acceleration sensors alternating the exiting Si based sensors.

• Culinary science and hospitality research
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• v.10 no.1
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• pp.64-81
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• 2004

Recently, the demand for utensils related to wine business has been growing from the wine consumers in Korea in order to enjoy flavor of wine more profoundly. This study propose a theory about the five senses that had been issued frequently in wine world attracting an attention of ever-changing food culture. In addition, it is to help sommeliers and devotes to learn the knowledge about the wine. To fully appreciate the different grape varieties and the subtle characteristics of wines, it is essential to have a glass with shape if fine-tuned for the purpose. The shape is responsible for the quality and intensity of the bouquet and the flow of the wine. This study has been performed with Riedel glass that has been appreciated as one of the finest wineglass in the world to investigate the effect of glass to the wine tasting. This study should be followed by further study with other tasting glass such as INAO and Le Taster glass to be generalized. The study is also needed about not only wineglass but wine accessories such as cork-screw, decanting and wine cooler.