• Journal of the Korean Electrochemical Society
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• v.6 no.4
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• pp.242-249
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• 2003

Zn electrode was widely used as an anode material in alkaline battery systems in highly concentrated KOH electrolyte, however it was well known that its cycle life is significantly shortened by growth of dendrite due to the high dissolution of $Zn(OH)_2$ and rapid electrochemical reaction. In this study when by the additives such as $Ca(OH)_2$, Citrate, tartrate and Gluconate were added to $40\%$ KOH electrolyte at solution temperature of $25^{\circ}C$ and the amount of $5wt\%\;Pb_3O_4$ was mixed to Zn electrode and then the effect of $Pb_3O_4$ and additives on the electrochemical behavior of Zn electrode was investigated by Potentiodynamic Polarization Curves, Cyclic Voltammetry, Accelerated Life Cycle lest, and SEM image analyses. The addition of $Pb_3O_4$ reduced the corrosion rate of Zn electrode. The corrosion potential of Zn electrode with $Pb_3O_4$ was higher or lower than that of pure Zn electrode however was not influenced practically to the open circuit voltage. And the addition of 4 type additives had an important role in improving both cycle life in accelerated cycle life test and corrosion resistance. Furthermore the additive of Tartrate indicated comparatively a good effect to corrosion resistance as well as charging-discharging property Improvement among those four type additives.

• Journal of the Korean Electrochemical Society
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• v.6 no.4
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• pp.250-254
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• 2003

In this study, the IR drop theory was adopted to explain the initiation of crevice corrosion in the framework of IR drop in crevice electrolyte. Furthermore, the electrochemical polarization was measured to study the mechanism of crevice corrosion for type STS430 stainless steel. lest method adopts under condition that the size of specimen is $10\times20\times5mm,\;in\;1N\;H_2SO_4+0.1N\;NaCl$ solution, and the artificial crevice gap sizes are three kinds, the Micro capillary tube size is inner diameter 0.04 mm, outer diameter 0.08 mm. Crevice corrosion is measured under the applied voltage of passivation potential -200mV/SCE, resulted from anodic potentio-dynamic polarization to the external surface along the crevice. The potential difference was measured by depth profile by Micro capillary tube which inserted in the crevice. The obtained results of this study showed that 1) As artificial crevice gap size became narrow, the current density was increased, whereas no crevice corrosion was found in the crevice gap size $3\times0.5\times16mm\;in\;1N\;H_2SO_4+0.1N\;NaCl\;solution\;at\;20^{\circ}C$ 2) potential of the crevice was about from -220 to -358mV which is lower than that of external surface potential of -200mV The results so far confirmes that the potential drop(so-called IR drop) in the crevice is one of the major mechanisms the process of crevice corrosion for 430 stainless steel.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.879-886
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• 2014

This study was conducted to test in vitro the antagonistic effect of composted liquid manure (CLM) against soil-borne turfgrass pathogenic fungi, Rhizoctonia solani AG-2-2 (IIIB) (brown patch), R. solani AG-2-2 (IV) (large patch), and Sclerotinia homoeocarpa (dollar spot) for environmentally friendly turfgrass management. CLMs were collected from 9 livestock excretion treatment facilities around the country including Gunwi (GW), Hapcheon (HC), Hoengseong (HS), Icheon (IC), Iksan (IS), Muan (MA), Nonsan (NS), and Yeoju (YJ). CLMs of IC, GW, and IS showed s ignificant (p < 0.05) mycelium growth inhibition that was 17.8%, 20.4%, and 48.0% against R. solani AG-2-2 (IIIB), R. solani AG-2-2 (IV), and S. homoeocarpa, respectively. A t otal of 110 bacterial isolates were obtained from the CLMs that showed antagonistic effects. Among them, 5, 4, and 10 microbe isolates showed promising antifungal activity against mycelium growth of R. solani AG-2-2 (IIIB), R. solani AG-2-2 (IV), and S. homoeocarpa, respectively. The bacterial isolates ICIIIB60, GWIV70, and ISSH20 effectively inhibited the mycelial growth of three soil-borne turfgrass pathogens. Selected bacterial isolates were identified as Alcaligenes sp., Bacillus licheniformis Ab2, and B. subtilis C7-3 through 16s rDNA gene sequence analysis. Among 5 fungicides, the most compatible fungicide with ICIIIB60, GWIV70, and ISSH20 was tebuconazol, toclofos-methyl and toclofos-methyl, respectively. These findings suggested that CLMs could be effectively used not only as organic liquid fertilizer sources but also as biological control agents for soil-borne turfgrass diseases such as brown patch, large patch, and dollar spot.

• Korean Security Journal
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• no.18
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• pp.1-20
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• 2009

Nowadays most nations around the world including Korea have experienced absolute shortages of available urban space. To solve various problems of the city, each nation constantly tends to extend the underground space. However there is a serious problem in making use of the underground space. Especially new terrorism coming into existence after 9.11 terror turns into the so-called ‘soft target’ which has something to do with public transportation facilities available to most people. Good examples are like these: poisonous gas attacks in Tokyo subway in 1995, Daegu subway station fire in 2003, serial bomb blast of London subway in 2005. In spite of being a concern on incidents related to the underground space it is inevitable to utilize the underground space and the tendency is growing. But Korea lags badly behind in foreign countries in this field and so seeking measures is urgently needed. Therefore the aim of this study is to note visible damages stemmed from the domestic and foreign underground space and propose more effective and adequate measures. Safety measures of terrorism are associated to minimize damage out of terrorism and they are as follows. In the first place, preparing protective equipment for saving a life from fire attacks and poisonous gas is needed urgently. In the second place, counterpart management on the spot and systematic security training should be established in order to minimize injury. In the third place, fire escapes must be provided for a rapid evacuation of potential unspecified individuals. In the fourth place, building up a network of related institutions is required for a systematic omnidirectional counterpart. Finally the Korean government ought to take fast and appropriate actions for the injured and bereaved family of the terror incident.

• Transactions of the Korean hydrogen and new energy society
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• v.9 no.4
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• pp.169-176
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• 1998

An experimental study on effect of vapor-cooled heat stations in a 5.5 liter cryogenic vessel has been performed. The cryogenic vessel is made of stainless steel of thickness of 1mm and insulated by the combined insulation of vacuum, MLI(multi-layer insulation) and vapor-cooled radiation shield. Vapor-cooled heat stations are also constructed based on the 1-dimensional thermal analysis to reduce the heat inleak through a filling tube. Thermal analysis indicates that the vapor-cooled heat stations can substantially enhance the performance of vessel for cryogenic fluids with high $C_p/h_{fg}$ where $C_p$ the specific heat and $h_{fg}$ the heat of vaporization, such as $LH_2$ and LHe. The experimental results for $LN_2$ shows that the total heat inleak into inner vessel consists of 14% radiation and 86% conduction through the filling tube. Therefore, it is expected that the conduction heat in leak of the vessel for high $C_p/h_{fg}$ cryogenic fluids can be significantly reduced. powders. The amount of copper coating was 20wt%. In order to examine corrosion behavior of the electrodes, the corrosion current and the current density, in 6M KOH aqueous solution after removal of oxygen in the solution, were measured by potentiodynamic and cyclic voltamo methods. The results showed that Co in the alloy increased corrosion resistance of the electrode whereas Ni decreased the stability of the electrode during the charge-discharge cycles. The electrode used Si sealant as a binder showed a lower corrosion current density than the electrode used PTFE and the electrode used Cu-coated alloy powders showed the best corrosion resistance.

• Transactions of the Korean hydrogen and new energy society
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• v.9 no.4
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• pp.161-167
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• 1998

It has been investigated the effects of alloying elements and binders on the corrosion behavior of metal hydride electrodes for anode of Ni/MH secondary battery. The $AB_5$-type alloys, $(LM)Ni_{4.49}Co_{0.1}Mn_{0.205}Al_{0.205}$ and $(LM)Ni_{3.6}Co_{0.7}Mn_{0.3}Al_{0.4}$, were used for the experiments. The electrodes were prepared by mixing and cold-pressing of alloy powders with Si sealent or PTFE powders, or cold-pressing the electroless copper coated alloy powders. The amount of copper coating was 20wt%. In order to examine corrosion behavior of the electrodes, the corrosion current and the current density, in 6M KOH aqueous solution after removal of oxygen in the solution, were measured by potentiodynamic and cyclic voltamo methods. The results showed that Co in the alloy increased corrosion resistance of the electrode whereas Ni decreased the stability of the electrode during the charge-discharge cycles. The electrode used Si sealant as a binder showed a lower corrosion current density than the electrode used PTFE and the electrode used Cu-coated alloy powders showed the best corrosion resistance.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.3
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• pp.58-65
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• 2015

Compared to pavement of Chinese palace gardens, those of private gardens in south part of the Yangtze River(長江) in China shows variety of patterns. In order to figure out what causes the difference in paving pattern, this article focuses on the traditional Chinese ideologies during the all time. An analysis on 'Classical Gardens of Suzhou', which has been designated as UNESCO World Heritage, was used to determine how ideologies have influence on paving pattern of Classical Gardens. As a result, various Chinese ideologies such as Nature worship, Totemism, Confucianism, Taoism, Buddhism, and Folk Culture were found in paving patterns of the private gardens. Pattern of sun in the Retreat & Reflection Garden(Toisawon) is an example of Nature worship among primitive beliefs of ancient China. Phoenix pattern of the Couple's Retreat Garden(Ouyuan, Liuyuan) reflects Totemistic beliefs. Confucianism is the underlying philosophy of Eight Square pattern, Six Square pattern, and Cross Square pattern. These patterns were mainly used to pave large area and easily found in many gardens. Patterns reflect Taoism are "Wufu holding life" pattern(the Five blessing holding life, 五福捧壽), Flat peach pattern, and Alluding Eight Immortals pattern. Paving patterns related to Buddhism are patterns of 'Eight treasures' and Endless knot pattern appears most frequently since it expresses concept of reincarnation well. Paving patterns shows folk culture and beliefs of the time in China are bat, butterfly, dragonfly, frog, carp, and coin(ingot).

• Journal of the Korean Electrochemical Society
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• v.3 no.3
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• pp.162-168
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• 2000

The influence of phenolsulfunate concentrations on electroplating characteristics and electrochemical behaviors was investigated with a viewpoint of electrolyte aging using the circulation cell and potentiostate And comparison of tinplate coating appearance such as glossiness and Image clarify has been also studied with varying of phenolsulfonic acid (PSA) solutions. As the aging of electrolyte proceeded, the limiting current density was moved to a lower current density region by the limitation of mass transfer, and higher phenolsulfunate concentrations resulted in the narrower optimum current density range and deterioration of coating surface of tinplates. The difference of the limiting current density was not remarkable with increasing electrolyte temperature. Thus the electrolyte aging was attributed to the limitation of thermally-activated process such as mass transfer of reducible ions. It has also been considered that the accumulation of phenolsulfonate suppressed normal electrotinning reaction by reducing the mobility of stannous ions, taking into account of the smaller effect of electrolyte aging. Experiments showed similar polarization behavior between the electrolyte of high phenolsufonate solution and the aged one, which comes to conclude that the accumulation of phenolsulfonate is one of the major causes of electrolyte aging.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.177-187
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• 2005

For the comparison of feeding behavior of Nilaparvata lugens among different rice varieties, electrical penetration graph (EPG) technique was used. Ten rice varieties were selected from national-widely recommended rice varieties cultivating in Chungnam province. The correlation between feeding duration and honeydew amount excreted was investigated, and the types of EPG pattern were analyzed among rice varieties. The EPG patterns divided into 6 types according to electrical specific feature, respectively. Type 1 pattern was a searching feeding sites, resting or wandering on a rice plant. Type 2 pattern was appeared when the insect untaken from phloem sieve element. Type 3 pattern was observed when the insect piercing into the rice plant. Type 4 pattern was observed when the insect salivating in rice plant. Type 5 pattern was observed when the insect ingesting from the xylem. Type 6 pattern was observed when the stylet moving in cell. Feeding duration time on Gum-nam was significantly shorter than Dong-jin, Dae-ahn, Dong-ahn, Dae-san. Also, on Gun-nam, it was shown that the brown planthopper did not penetrate the cuticle for a long time. The total number of excreted honeydew droplets by the brown planthopper was the greatest in Dong-jin variety and the least in Gum-nam variety. In proportion to phloem feeding time, the number of honeydew droplets had been increased. According to the results of EPG patterns and honeydew droplets analysis, N. lugens seems to prefer Dong-jin, Dong-ahn, Dae-san, and Dae-ahn to Gum-nam, Da-san, and Nam-chun rice plant variety.

• Journal of Service Research and Studies
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• v.10 no.3
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• pp.119-138
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• 2020

Unlike the era of manufacturing-oriented industrial economy in the past, the era of service economy has characteristics intangible goods center, knowledge universalization, and expansion of needs, and many things that are of the economy are changing. In the past, the change in the environment was not fast, so even after analyzing the changed environment and deriving the talent needed for the company, it was possible to maintain a talent for the organization for a long time, so it is not proactive to build and apply talent. It became difficult to manage effectively. Therefore, in this paper, we conducted a normative study for deriving a desirable talent model rather than a descriptive human resource model. Human resources image suitable for the modern service economy era, the modern economic society and modern spirit were analyzed and reflected. The model in which the two opposing members of the organization, managers and employees, interact intensely and balance dialectically. A desirable talent in a modern organization must play the role of a manager, and the management and talent models in a modern organization can be said to be connected to each other like the front and back sides of a coin. The philosophy of human resources was presented in five dimensions: human, historical, social, economic, and management. The human resource model from eight factors: mastery, rationality, wisdom, customer orientation, innovation, flexibility, autonomy, collaboration. This study suggested that general talent model may vary depending on the company's type, empirical follow-up studies are needed the talents in each company in the future.