• Economic and Environmental Geology
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• v.43 no.2
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• pp.73-84
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• 2010

Gold and silver deposits within the Eunjeok and Sangeun mines are located in Yeongam district, Cheollanamdo-province. They are composed of vein ore bodies infilling the fractures of Cretaceous rhyolitic tuff. The Eunjeok mine have three gold and silver bearing hydrothermal veins which is infilling the fracture of rhyolitic tuff. Major ore minerals within the Eunjeok and Sangeun mines are arsenopyrite, pyrite, chalcopyrite, sphalerite and galena and minor ores are electrum, native silver and argentite. Sericitization is dominant in alteration zone and chloritization and dickitization is minor. Quartz veins in the Eunjeok and Sangeun mine have the similar paragenesis and vein textures such like breccia, crustiform, comb and vuggy morphology indicating the formation of typical epithermal environment. In order to carry out the preliminary feasibility study of mine according to the commodity and elucidate the occurrence features of mineral resources from Eunjeok and Sangeun mine, common commodity (Pb, Zn, Cu, Fe, Mo, W, Au and U), and industrial commodity (In, Re, Ga, Ge, Se, Te, Y, Eu and Sm) for 17 ore specimen were analyzed. It is tentatively thought that there is no exploitable mine for iron, lead, zinc, copper, tungsten and uranium based on the preliminary result. If the reserves are secured through the detailed prospecting in case of molybdenum and silver, it is tentatively thought that there will be exploitable deposits depending on international metal price. If we assume the vein width from 0.25 m to 2 m including alteration zone with the gold grade of 80g/t, it is inferred that the resources amount of the Eunjeok-Sangeun mines range from 6.5 to 65ton. However, as the vein structure of the Eunjeok and Sangeun mines is developed together with alteration zone, it should be estimated to include potential alteration zone in order to yield the average grade. It is needed to carry out more exploration in the near future because the reserves can be flexibly estimated according to the change of average grade considering the alteration zone.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.78
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• pp.93-117
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• 2018

In all countries of the world, the development of trade is an important factor for the survival of the national economy. Increased export will lead to national economic growth. Export is directly linked to employment, and the industrial structure will be developed in the direction to produce products of comparative advantages. Therefore, every country around the world is trying to promote export regardless of the size of its economy. Accordingly, this paper focused on the promotion of export of domestic companies. It proposed to cultivate trade experts to promote export of domestic companies. The following five methods were proposed to materialize the proposal. First, it is important to foster trade experts to expand and foster the one-person creative companies. In particular, it is important to develop a professional education curriculum. It is necessary to design and conduct a systematic curriculum throughout the process including follow-up after education such as teaching detailed procedures for establishing a trade business, identification of relevant regulations and related organizations, understanding of special features of each exporting country, and details of exporting procedures through specialist training for the individual industries, helping themto keep their network steady so that they can easily get help from consultants. Second, it is necessary to educate traders working in the field to make them trade experts and utilize themin on-the-job training and consulting. To do this, it is necessary to introduce systematic consultant selection process, and to introduce a systemto educate and manage them. It is because, we must select the most appropriate candidates, educate themto be lecturers and consultants, and dispatch themto the field, in order to make the best achievement in export. Nurturing trading professionals utilizing the current trading workers to activate export of domestic companies can be more efficient through cooperation of trading education agencies and related agencies in various industries. Third, it is also proposed to cultivate female trade experts by educating female trade workers whose career has been disrupted. It is to provide career disrupted women with opportunities to work after training them as trade professionals and to give manpower pool to domestic companies that are preparing for export. Fourth, it is also proposed to educate foreign students living in Korea to be trading experts and to utilize them as trading infra. They can be trading professionals who will contribute to the promotion of export. In the short term, they will be provided with opportunities for employment and start-upin the field of trade, and in the mid- to long-term, they may develop a business network between Korea and their own countries. To this end, we need to improve the visa system, expand free trade education opportunities, and support them so that they can establish small but strong enterprises. Fifth, it is proposed to proactively expand trade education to specialized high school students. Considering that most of domestic companies pursuing activation of export are small but strong companies or small and mediumsized companies, they may prefer high school graduates rather than university graduates because of financial limitations. Besides, the specialized high school students may occupy better position in the job market if they are equipped with expertise in trading. This study can be meaningful, in that it is the first research that focuses on cultivating trading experts to contribute to the export activation of domestic companies. However, it also has a limitation that it has failed to reflect the more specific field voices. It is hoped that detailed plans will be derived from the opinions of the employees of domestic companies making efforts to become an export company in the related researches in the future.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.8
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• pp.759-769
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• 2013

Electronic equipment has been applied to virtually every area associated with commercial, industrial, and military applications. Specifically, electronics have been incorporated into avionics components installed in aircraft. This equipment is exposed to dynamic loads such as vibration, shock, and acceleration. Especially, avionics components installed in a helicopter are subjected to simultaneous sine and random base excitations. These are denoted as sine on random vibrations according to MIL-STD-810F, Method 514.5. In the past, isolators have been applied to avionics components to reduce vibration and shock. However, an isolator applied to an avionics component installed in a helicopter can amplify the vibration magnitude, and damage the chassis, circuit card assembly, and the isolator itself via resonance at low-frequency sinusoidal vibrations. The objective of this study is to investigate the dynamic characteristics of an avionics component installed in a helicopter and the structural dynamic modification of its tray plate without an isolator using both a finite element analysis and experiments. The structure is optimized by dynamic loads that are selected by comparing the vibration, shock, and acceleration loads using vibration and shock response spectra. A finite element model(FEM) was constructed using a simplified geometry and valid element types that reflect the dynamic characteristics. The FEM was verified by an experimental modal analysis. Design parameters were extracted and selected to modify the structural dynamics using topology optimization, and design of experiments(DOE). A prototype of a modified model was constructed and its feasibility was evaluated using an FEM and a performance test.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.1
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• pp.27-41
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• 2008

Distribution characteristics of phytoplankton community were investigated by HPLC and flow cytometry in Jeju Strait and the Northern East China Sea (NECS) in May 2004, in order to understand the relationship between physical environmental factors and distribution pattern of phytoplankton communities. Based on temperature and salinity data, three distinct water masses were identified; warm and saline Tsushima Warm Current (TWC), which is flowing from northwest of Jeju Island, warm and low saline water at the center of Jeju Strait, which is originated from China Coastal Water (CCW) and relatively cold and high saline water originated from Yellow Sea at the bottom of the Jeju Strait. At Jeju Strait, less saline water (<33 psu) of 15 km width occupied surface layer up to 20 m which located at 20 km offshore and strong thermal front between warm and saline water and cold and less saline water was found in the middle of the Jeju Strait. Vertical transect of temperature and salinity at the NECS also showed that low saline (<33 psu) water occupied the upper 20 m layer and cold and saline water was present at the eastern part. Chl a was measured as $0.06{\sim}3.07\;{\mu}g/L$. Spring bloom of phytoplankton was recognized by the high concentrations of Chl a at the low saline water masses influenced by the CCW and subsurface chlorophyll maximum layer appeared between $20{\sim}30\;m$ depth, which was at thermocline depth or below. Abundances of Synechococcus and picoeukaryote were $0.2{\sim}9.5{\times}10^4\;cells/mL$ and $0.43{\sim}4.3{\times}10^4\;cells/mL$, respectively. Dinoflagellate, diatom and prymnesiophyte were major groups and minor groups were chlorophyte+prasinophyte, chrysophyte, cryptophyte and cyanophyte. Especially high abundance of dinoflagellate was identified by high concentration (>1\;{\mu}g/L$) of peridinin at the bottom of the thermocline, which showed an outbreak of red tide by high density of dinoflagellates. Abundances of picoeukaryote in Jeju Strait were about $5{\sim}10$ times higher than abundance measured in Kuroshio water and showed a good correlation with Chl b (Pras+Viola), which implies the most of population of picoeukaryote was composed of prasinophytes. Prochlorococcus was not detected at all, which suggests that Kuroshio Current did not directly influenced on the study area. Based on the strong negative correlations between biomass of phytoplankton (Chl a) and temperature+salinity, the primary production and biomass of phytoplankton in the study area were controlled by the nutrients supply from CCW.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.477-483
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• 2008

$La_{0.7}Sr_{0.3}Co_{0.2}Fe_{0.8}O_{3-{\delta}$ oxide was synthesized by a citrate method and a typical dense membrane of perovskite oxide has been prepared using as-prepared powder by pressing and sintering at $1300^{\circ}C$. Precursor of $La_{0.7}Sr_{0.3}Co_{0.2}Fe_{0.8}O_{3-{\delta}$ prepared by citrate method was investigated by TGA and XRD. Metal-citrate complex in precursor was decomposed into perovskite oxide in the temperature range of $260{\sim}410^{\circ}C$ but XRD results showed $SrCO_3$ existed as impurity at less than $900^{\circ}C$. Electrical conductivity of membrane increased with increasing temperature but then decreased over $700^{\circ}C$ in air atmosphere ($Po_2=0.2atm$) and $600^{\circ}C$ in He atmosphere ($Po_2=0.01atm$) respectively due to oxygen loss from the crystal lattice. The oxygen permeation flux increased with increasing temperature and maximum oxygen permeation flux of $La_{0.7}Sr_{0.3}Co_{0.2}Fe_{0.8}O_{3-{\delta}$ membrane with 1.6 mm thickness was about $0.31cm^3/cm^2{\cdot}min$ at $950^{\circ}C$. The activation energy for oxygen permeation was 88.4 kJ/mol in the temperature range of $750{\sim}950^{\circ}C$. Perovskite structure of membrane was not changed after permeation test of 40 h and the membrane was stable without secondary phase change with 0.3 mol Sr addition.

• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.554-564
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• 1996

Oxygen reduction in an alkaline fuel cell was studied by using perovskite of $La_{0.6}Sr_{0.4}Co_{1-x}Fe_xO_3$(x=0.00, 0.01, 0.10, 0.20, 0.35, and 0.50) as an oxygen electrode catalyst. The changes in the catalytic properties as a function of Fe content were investigated by XRD, TG, and TPR. XRD patterns gave different lattice parameters of the catalysts. TG study revealed that Fe was so stabilized in the perovskite structure as to be hardly reduced even up to $900^{\circ}C$, and the amount of oxygen which was eliminated at high temperature increased with the fraction of Fe because Fe induced the increase of Co-O binding energy. From TPR study, ${\alpha}$-(low temperature peak) and ${\beta}$-(high temperature peak)states were observed. The bond strength of the ${\beta}$-species which was associated strongly with Co of the perovskite increased proportionally with the fraction of Fe. The ${\alpha}$-species, reversible oxygen, was the active species in the oxygen reduction. The ${\alpha}$-peak temperature which reflected the binding energy between Co and ${\alpha}$-state oxygen moved to lower temperature with the increase of lattice parameter of the catalytst due to the increase of Fe content. The decrease in the binding energy increased the activity in the oxygen reduction, but the decrease of ${\alpha}$-species with the increase of Fe content decreased the activity. The increase in the surface area with Fe content had little effect on the activity.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1078-1086
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• 1996

The peroxo-polytungstic acid was formed by the direct reaction of tungsten powder with the hydrogen peroxide solution. Peroxo-polytungstic powder were prepared by rotary evaporator using the fabricated on to ITO coated glass as substrate by dip-coating method using $2g/10mL(W-IPA/H_2O)$ sol solution. A substrate was dipped into the sol solution and after a meniscus had settled, the substrate was withdrawn at a constant rate of the 3mm/sec. Thicker layer could be built up by repeated dipping/post-treatment 15 times cycles. The layers dried at the temperature of $65{\sim}70^{\circ}C$ during the withdrawn process, and then tungsten oxides thin film was formed by final heating treatment at the temperature of $230{\sim}240^{\circ}C$ for 30min. A linear rotation between the thickness of thin film and the number of dipping/post-treatment cycles for tungsten oxides thin films made by dip-coating was found. The thickness of thin film had $60{\AA}$ after one dipping. From the patterns of XRD, the structure of tungsten oxides thin film identified as amorphous one and from the photographs of SEM, the defects and the moderate cracks were observed on the tungsten oxides thin film, but the homogeneous surface of thin films were mostly appeared. The electrochemical characteristic of the $ITO/WO_3$ thin film electrode were confirmed by the cyclic voltammetry and the cathodic Tafel polaization method. The coloring bleaching processes were clearly repeated up to several hundreds cycles by multiple cyclic voltammetry, but the dissolved phenomenon of thin film revealed in $H_2SO_4$ solution was observed due to the decrease of the current densities. The diffusion coefficient was calculated from irreversible Randles-Sevick equation from the data obtained by the cyclic voltammetry with various scan rates.

• Journal of Korean Society of Forest Science
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• v.80 no.1
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• pp.42-53
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• 1991

1. The forest vegetation of the Mt. Baek-Hwa situated in the northwestern Kyungsangpookdo of Korea, on $36^{\circ}16^{\prime}00^{{\prime}{\prime}}{\sim}36^{\circ}19^{\prime}20^{{\prime}{\prime}}N$ and 127 53'20"~127 56'30"E was studied by the method of Zurich-Montpellier School. In the present time, the original vegetation have almost been dominated by substitutional communities such as secondary forests of Pinus, Quercus, Zelkova, Acer or Fraxinus and Pinus rzgida plantations. Some secondary forests developing along the ravine and in northwestern part of slope are, however, maintained in natural condition, and contain some species of the original climax vegetation. They are classified as follows : I. Quercus mongolica-Fraxinus siebol diana community(Mountain forests), I-A. Acer pseudo-sieboldianum -Carex okamotoi group, I-B. Pinus densiflora group, I-B-a. Typical subgroup, I-B-b. Rhododendron schlippenbachii subgroup, II. Fraxinus rhynclzophylla-Acer mono community(Valley Forests), II-A. Acer pseudo-sieboldianum group, II-B. Zelkova serrata group, II-B-a. Typical subgroup, II-B-b. Lindera erythrocarpa subgroup, II-C. Querczrs serrata-Platycarya strobilacea group, II-C-a. Typical subgroup, II-C-b. Lindera erythrocarpa subgroup. 2. Judging from the coincidence method, the structure and distribution of the forest communities was more related to topography than altitude. 3. Considering the actual vegetation, relict species, occurrence of natural seedlings and saplings, climate, successional trends of trees and topographic or edaphic climax conditions, it seems that potential natural vegetation of the area mainly composed of Quercus mongolica, Carpinus laxiflora, Zelkova serrata, Fraxinus rhynchophylla. 4. The flora of the vascular plants collected from this area consists of 108 families, 371 genera, 613 species, 2 subspecies, 88 varieties, 6 forms and 709 taxa in total.

• Journal of Arbitration Studies
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• v.14 no.1
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• pp.273-314
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• 2004

There is a belief in the construction industry that the traditional court system may not be an ideal forum to effectively and efficiently resolve construction disputes due to the protracted proceedings and the three tier appeal system resulting in a long delay in the final and conclusive settlement of the dispute, relatively high costs involved, the lack of requisite knowledge and experience in the relevant industry, etc. Hence, they assert that certain alternative dispute resolution ('ADR') methods, such as mediation, conciliation, arbitration or a new system for dispute settlement in the form of any combination thereof should be developed and employed for construction disputes so as to resolve them more promptly and efficiently to the satisfaction of all the disputants concerned. This paper discusses certain merits of such assertions and the need for additional considerations for effective resolution of the construction disputes in light of the complexity of the case, importance of expert witnesses, parties' relationship and non-level playing field of the construction industry and so on. At the same time, however, given the inherent nature of disputes rendering the parties involved in an adversarial position, it would rather be difficult, if not practically impossible, to satisfy all the parties concerned in the dispute. Accordingly, in this study, it is also purported to address the demerits of such assertions by studying the situation from a more balanced perspective, in particular, in relation to the operation of such ADRs. In fact, most of such ADRs as stipulated by special acts, such as the Construction Industry Basic Act of Korea, in the form of mediation or conciliation, have failed to get support from the industry, and as a result, such ADRs are seldom used in practice. Tn contrast, the court system has been greatly improved by implementing a new concentrated review system and establishing several tribunals designed to specialize in the review and resolution of specific types of disputes, including the construction disputes. These improvements of the court system have been warmly received by the industry. Arbitration is another forum for settlement of construction disputes, which has grown and is expected to grow as the most effective ADR with the support from the construction industry. In this regard, the Korean Commercial Arbitration Board ('KCAB') has established a set of internal rules end procedures in operation to efficiently handle construction disputes. Considering the foregoing, this paper addresses the most important elements of the arbitration, i.e., arbitration agreement and arbitral award, primarily focusing on the domestic arbitrations before the KCAB. However, since this parer is prepared for presentation at the construction disputes seminar for the public audience, it is not intended for academic purposes, nor does it delve into any specific acadcmic issues. Likewise, although this paper addresses certain controversial issues by way of introduction, it mainly purports to facilitate the understanding of the general public, including the prospective arbitrators on the KCAB roster without the relevant legal education and background, concerning the importance of the integrity of the arbitration agreement and the arbitral award. In sum, what is purported in this study is simply to note that there are still many outstanding issues with mediation, conciliation and arbitration, as a matter of system, institutional operation or otherwise, for further study and consideration so as to enhance them as effective means for settlement of construction disputes, in replacement of or in conjunction with the court proceeding. For this purpose, it is essential for all the relevant parties, including lawyers, engineers, owners, contractors and social activists aiming to protect consumers' and subcontractors' interests, to conduct joint efforts to study the complicated nature of construction works and to develop effective means for examination and handling of the disputes of a technical nature, including the accumulation of the relevant industrial data. Based on the foregoing, the parties may be in a better position to select the appropriate dispute resolution mechanism, a court proceeding or in its stead, an effective ADR, considering the relevant factors of the subject construction works or the contract structure, such as the bargaining position of the parties, their financial status, confidentiality requirements, technical or commercial complexity of the case at hand, urgency for settlements, etc.

• Management & Information Systems Review
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• v.22
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• pp.137-165
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• 2007

It seems high time to increase productivity by adopting e-business to overcome challenges posed by both external factors including the appreciation of Korean won, oil hikes and fierce global competition and domestic issues represented by disparities between large corporations and small and medium enterprises (SMEs), Seoul metropolitan and local cities, and export and domestic demand all of which weaken future growth engines in the Korean economy. The demands of the globalization era are for innovative changes in businessprocess and industrial structure aiming for creating new values. To this end, e-business is expected to play a core role in the sophistication of the Korean economy through new values and innovation. In order to examine business performance in e-business-adopting industries, this study analyzed the home shopping industry by closely looking into the financial ratios including the ratio of net profit to sales, the ratio of operation income to sales, the ratio of gross cost to sales cost, the ratio of gross cost to selling, general and administrative (SG&A) expense, and return of investment (ROI). This study, for best outcome, referred to corporate financial statements as a main resource to calculate financial ratios by utilizing Data Analysis, Retrieval and Transfer System (DART) of the Financial Supervisory Service, one of the Korea's financial supervisory authorities. First of all, the result of the trend analysis on the ratio of net profit to sales is as following. CJ Home Shopping has registered a remarkable increase in its ratio of net profit rate to sales since 2002 while its competitors find it hard to catch up with CJ's stunning performances. This is partly due to the efficient management compared to CJ's value of capital. Such significance, if the current trend continues, will make the front-runner assume the largest market share. On the other hand, GS Home Shopping, despite its best organized system and largest value of capital among others, lacks efficiency in management. Second of all, the result of the trend analysis on the ratio of operation income to sales is as following. Both CJ Home Shopping and GS Home Shopping have, until 2004, recorded similar growth trend. However, while CJ Home Shopping's operating income continued to increase in 2005, GS Home Shopping observed its operating income declining which resulted in the increasing income gap with CJ Home Shopping. While CJ Home Shopping with the largest market share in home shopping industryis engaged in aggressive marketing, GS Home Shopping due to its stability-driven management strategies falls behind CJ again in the ratio of operation income to sales in spite of its favorable management environment including its large capital. Companies in the Group B were established in the same year of 2001. NS Home Shopping was the first in the Group B to shift its loss to profit. Woori Home Shopping has continued to post operating loss for three consecutive years and finally was sold to Lotte Group in 2007, but since then, has registered a continuing increase in net income on sales. Third of all, the result of the trend analysis on the ratio of gross cost to sales cost is as following. Since home shopping falls into sales business, its cost of sales is much lower than that of other types of business such as manufacturing industry. Since 2002 in gross costs including cost of sales, SG&A expense, and non-operating expense, cost of sales turned out to have remarkably decreased. Group B has also posted a notable decline in the same sector since 2002. Fourth of all, the result of the trend analysis on the ratio of gross cost to SG&A expense is as following. Due to its unique characteristics, the home shopping industry usually posts ahigh ratio of SG&A expense. However, more than 80% of SG&A expense means the result of lax management and at the same time, a sharp lower net income on sales than other industries. Last but not least, the result of the trend analysis on ROI is as following. As for CJ Home Shopping, the curve of ROI looks similar to that of its investment on fixed assets. As it turned out, the company's ratio of fixed assets to operating income skyrocketed in 2004 and 2005. As far as GS Home Shopping is concerned, its fixed assets are not as much as that of CJ Home Shopping. Consequently, competition in the home shopping industry, at the moment, is among CJ, GS, Hyundai, NS and Woori Home Shoppings, and all of them need to more thoroughly manage their costs. In order for the late-comers of Group B and other home shopping companies to advance further, the current lax management should be reformed particularly on their SG&A expense sector. Provided that the total sales volume in the Internet shopping sector is projected to grow over 20 trillion won by the year 2010, it is concluded that all the participants in the home shopping industry should put strategies on efficient management on costs and expenses as their top priority rather than increase revenues, if they hope to grow even further after 2007.