• Journal of the Korean Ceramic Society
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• v.13 no.2
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• pp.31-38
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• 1976

Korean tremoitic talc, wollastonite and clay have been used to develop a wall tile body to appropriate to the fast firing process. Some of ceramic properties of the raw materials were investigated by X-ray diffraction, thermal analysis and chemical analysis. The body compositions were formulated from the range of 35~75% tremolitic talc, 0~30% wollastonite and 25~35% plastic clay. Thermal gravity analysis and thermal expansion were tested for each of unfired bodies to study the correlation between thermal dehydration and linear shrinkage during the firing procedure. Linear shrinkage and water absorption of the fired bodies at the various temperature were taken as a measures for determining the proper firing range of the bodies. Increasing the content of wollastonite and firing temperature, the thermal expansion of the fired body showed the gradual decrease, and the thermal expansion curves showed a tendency to straighten. These observations may be resulted from the fact that the amounts of diopside and anorthite formed were gradually increased and those of quartz relatively decreased. The optimum compositions of the wall tile bodies for fast firing are 30% clay, 10~20% wollastonite and 50~60% tremolitic talc.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.76
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• pp.1-20
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• 2017

The industrial technology (including trade secrets), which is commonly understood as systematic and applied technical knowledge, can be transferred to third parties by contracting for the transfer of technology or by granting of a licence. The activity of industrial espionage, due to the gradual increase of the economic interests of intellectual property, is displaying intensively in order to gain advanced technology information. With our outstanding high technology, but compared to the level of the advanced countries, the technical protection systems, the legal protection measures and the systematic management thereof may still be insufficient. Our industrial technology outflow abroad, due to the vulnerability to the security control system in our country, has been increasing since the 2000. Computer software and SNS, such as smart devices, appear as a rapid change in the technical information environment. In order to minimize the dead zone of a new industrial security, the country's organic activity is being conducted. In 2006, Industrial Technology Outflow Prevention and Protection Law was enacted, which emphasized the responsibilities of the country. In this paper for the economic entity's efforts to prevent technology leakage oversea, I have looked to how the industrial technology can be protected in terms of national security and economic benefits of our enterprises. To solve the above-mentioned problems hereof, Korean government should willingly establish a reliable legal system for supporting to enterprise's operations, and Korean companies should autonomously introduce a synthetic technology protection system and incorporate the confidentiality clauses in an international transfer of technology agreement with third parties.

• Journal of Powder Materials
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• v.15 no.3
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• pp.210-213
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• 2008

Elongated CdSe nanoparticles with a diameter of 3-7nm have been successfully synthesized using two surfactants of trioctylphospine (TOP) and hexadecylamine (HDA) at $160^{\circ}C$. The formation of elongated CdSe nanoparticles is possibly due to the cooperative effects from both the different binding capability of two surfactants (TOP and HDA) and intrinsically anisotropic crystal structure of the CdSe. The electron diffraction pattern of CdSe nanoparticles revealed the formation of wurzite phase. The CdSe samples showed red-shifted wavelength from 560 to 580nm with increasing the refluxing time due to the gradual growth of CdSe nanoparticles. The relatively broad absorption band can be attributed to the surface state of CdSe nanoparticles. The possible formation mechanism of elongated CdSe nanoparticles was proposed and the characteristics of CdSe have been discussed as well.

• Journal of Dairy Science and Biotechnology
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• v.28 no.1
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• pp.1-7
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• 2010

In 2009, the world dairy industry had the most impressive experience throughout all the experiences it had. The milk price in major regions fell to their lowest level for decades. Including Korea, the world economy is obviously slowing. The nations' export plunged due to the global economic recession, in result reduced industrial output and domestic demand. In Korea, the intake of liquid milk slightly decreased from 45 kg per capita in 2005 to 44.3 kg per capita in 2008. However, production and consumption of milk increased fast in China and India. According to 2008 statistics, total milk volume of the world trade reached 42 million tonnes and the major exporters of dairy products were EU, New Zealand, USA and Autralia. The tropical countries has traditionally consumed buffalo milk. The production of buffalo milk is increasing faster than cow milk. IDF expected that EU milk production would recover the medium term displaying a gradual growth over the milk quotas phasing-out period, while constantly remaining below the quota level.

• Structural Engineering and Mechanics
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• v.74 no.4
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• pp.533-545
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• 2020

An optimal design method for a spoke double-layer cable-net structure (SDLC) is proposed in this study. Simplified calculation models of the SDLC are put forward to reveal the static responses under vertical loads and wind loads. Next, based on an energy principle, the relationship among the initial prestress level, cross-sectional areas of the components, rise height, sag height, overall displacement, and relative deformation is proposed. Moreover, a calculation model of the Foshan Center SDLC is built and optimized. Given the limited loading cases, material properties of the components, and variation ranges of the rise height and sag height, the self-weight and initial prestress level of the entire structure can be obtained. Because the self-weight of the cables decreases with increasing of the rise height and sag height, while the self-weight of the inner strut increases, the total weight of the entire structure successively exhibits a sharp reduction, a gradual decrease, a slow increase, and a sharp increase during the optimization process. For the simplified model, the optimal design corresponds to the combination of rise height and sag height that results in an appropriate prestress level of the entire structure with the minimum total weight.

• Environmental Analysis Health and Toxicology
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• v.14 no.3
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• pp.81-85
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• 1999

Diazinon, an organophosphate pesticide, is relatively highly toxic to fish and causes vertebral malformation and behavioral change of fish at relatively low concentrations. To elucidate biochemical mechanism of the behavioral change of Oryzias latipes (killifish) caused by diazinon, the effect of the insecticide on acetylcholine esterase activities and the levels of some neurotransmitters were evaluated. Acetylcholine esterase activities in both head and body were significantly lowered at the concentration of 10 ppb of diazinon and acetylcholine contents in head tended to be upregulated with increasing concentration of diazinon. Exposure of killifish to 5000 ppb diazinon resulted in gradual decrease in acetylcholine content in body part with exposure time. Norepinephrine and serotonin concentrations in killifish head and body were highest at 1000 ppb of diazinon while neurotransmitter were relatively low in fish unexposed or exposed to lower dose of the pesticide, suggesting that increased norepinephrine and serotonin can partially account for diazinon-induced behavioral abnormality.

• The Korean Journal of Pain
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• v.11 no.2
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• pp.283-287
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• 1998

Background: Recently, pain clinic is attracting attention and interest of both physicians and laymen. It is the purpose of this article to analyze our 10 years' experience to seek and improve better protocol of treating pain. Methods & Materials: We analyzed retrospectively 11,235 patients who visited the clinic during 10 years from 1986 to 1996. Total number of hospital visits was 51,908. Male to female ratio was 35：65(3910：7325). Treatment modalities employed were SGB(stellate ganglion block), TPI(trigger point injection), etc. Results: Yearly distribution showed a gradual upward curve until 1992 and remains in a horizontal pattern thereafter. Of age distribution, 6th decades occupied the largest proportion(27.29%). As of disease entities, Low back pain & lower extremities pain comprised of the majority(34.01%) and the epidural block was most frequently given as a treatment. Conclusion: Pain clinic is improving rapidly as an important part of medical science in Korea and outpatients of clinic are on an increasing trend. So, anesthesiologists should be make every efforts to research for treatment of good quality.

• The Journal of Industrial Distribution & Business
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• v.8 no.6
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• pp.17-24
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• 2017

Purpose - The purpose of this study is to examine the current trends of women in management fields from an Australian perspective. With the increase of women in the workforce, this will prove to be a valuable study. Research design, data, and methodology - This paper observed past research on women in management in Australia and defined some factors on their characteristics. Comparisons between the unique characteristics of women in management in Australia compared to those in Asia or other Western countries were evaluated. Results - Our results have showed that there are an increasing number of women in the workforce in management areas in Australia, and they are steadily rising. The gradual shift of perception in society on women entering the workplace and working will continue to have a lasting effect on the number of women in careers of management. Conclusions - The perception of women being at-home moms and men working has begun to shift in the current era. With this change evident in many countries around the world, other countries will also be able to include more women into the workplace. Raising awareness of the issues women face in the management world will be beneficial for aiding future women leaders.

• Journal of the Korean Wood Science and Technology
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• v.22 no.1
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• pp.85-90
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• 1994

The flow properties of binder latices for paper coating were investigated, together with dynamic viscoelastic properties of latex films and electron micrographs of latices, under various conditions. The amphoteric latex, binder pigment latex and anionic latex were used in this work. The amphoteric latex has both anionic and cationic functional group on its surface. The binder-pigment with a core-shell structure has dual functions : plastic pigment and binder. The low shear viscosity of binder latices and clay slurry were measured with Brookfield vis cometer. At low-shear rates. the viscosity decreased with increasing particle size of latex. On the amphoteric latex surface, the carboxyl groups are assumed to be fully dissociated over the region of pH 9~12, but the density of negative groups seems to be increased because of the gradual decrease in the degree of dissociation of amino groups. Since the apparent particle size of latex increases with surface charge, the electroviscous effect can be observed. On the anionic latex surface, the charge density is assumed to be nearly constant above pH 8. However, below pH 8 the coagulation of particles could be observed probably because of the decrease in the charge density.

• Journal of the Korean Chemical Society
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• v.62 no.1
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• pp.7-13
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• 2018

The potential of zinc fluorides with different molar ratios of Zn/F was applied as a solid catalyst in the simultaneous reaction of transesterification and esterification of crude palm oil (CPO) for biodiesel production. These materials were prepared by the fluorolytic sol-gel technique with different fluorine contents. The resulting samples were investigated using elemental analysis, XRD, FT-IR, TG/DTG, $N_2$ physisorption measurements and SEM. The results exhibited that the presence of fluorine strongly affected the catalytic activity in the biodiesel production. The catalysts with smaller fluorine contents (${\leq}1$) showed the best performance in all of the observed samples, yields from 92.94 to 89.95, 87.38 and 85.21% with increasing fluorine contents, respectively. The yield toward the formation of biodiesel depended on the phase and particle sizes of catalysts, but it was not influenced by surface area, pore size, and volume of the samples. The recovered catalyst showed a gradual decrease in activity over three cycles of same reactions.