• Applied Biological Chemistry
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• v.27
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• pp.68-79
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• 1984

An increased population and rapidly expanding industrial development have led to enormous amounts of various domestic and industrial wastes. The proper disposal of ever-increasing wastes is a growing global problem. Land treatment is one of the rational approaches that are environmentally safe and economically practical. It has long been practised in many sites. Recycling of industrial wastes on agricultural land can provide better possible means for maintaining environmental quality and utilizing waste-resources. Even though industrial wastes are beneficial as soil amendment and fertilizer, they have some limitation on land application because of wide variability as well as physicochemical problem in their composition. A direct application of solid and liquid wastes on land is being practised in Korea and some experimental results are presented. The direct application of fermentation waste on rice resulted in a 6 percent yield increase. Another organic residue from glutamic acid fermentation is widely used not only as a direct application as a liquid fertilizer but also for a raw material of organic compound fertilizer. These wastes are much promising as sources of plant nutrients, since they have large amounts of nutrients, especially nitrogen with few toxic metals. On the other hand, fertilizers developed from inorganic industrial wastes include calcium silicate, calcium sulfate and ammonium sulfate. The calcium silicate fertilizer simply produced from slag, by-product of iron and steel manufacturing plant is one of the most successful example of the conversion of wastes to fertilizer and slag production capacity totals to over three million MT/year. About 200,000 MT of calcium silicate fertilizer is currently applied in the paddy rice every year. Calcium sulfate, a waste from the wet phosphoric acid process is to some extent used as a filler of compound fertilizers but quite large quantites are directly applied for the reclamation of tidal flat.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.10
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• pp.1033-1041
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• 2012

Performance evaluation of a direct carbon fuel cell (DCFC) was conducted according to coals and a graphite particle. Several fuel properties such as thermal reactivity, textural structure, gas adsorption characteristic, and functional groups on the surface of fuels were investigated and their effects on electrochemistry were discussed. The strong carbon structure inside of fuels led the rapid potential decreasing in high current density region, because it caused small surface area and low pore volume. The functional groups on the surface were related to the low current density region. The maximum current density and power density of fuels were affected by the total carbon content in fuels. The effect of operating conditions such as stirring rate and operating temperature was investigated in this study.

• The Korean Journal of Applied Statistics
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• v.24 no.3
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• pp.455-464
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• 2011

Overseas direct investment is constantly on the rise, while domestic investment has been slowing and has led to concerns that the expansion of overseas investment may be weakening domestic investment. Considering the change of environment as economic growth, this paper analyzes the relationship between domestic and overseas investment using a regression tree. The result shows that overseas investment substituted domestic investment in the past (before 1985); however, they compensated for each other during the rapid growth period based on exports (1986-1997). The relationship turns out to be insignificant after the Asian currency crisis(after 1998). In addition, this paper also examines the factors determining domestic facilities investment and overseas direct investment at each stage of the changes in their influence due to globalization. Taking into account the results, we need to re-evaluate the current pattern of corporate investment apart from the past restricted point of view to help domestic enterprises efficiently utilize the international production network and resources.

• Transactions of Materials Processing
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• v.29 no.2
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• pp.103-112
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• 2020

This study explores the effects of different pre-machining conditions on the deposition characteristics and mechanical properties of austenitic stainless steel samples repaired using direct energy deposition (DED). In the DED repair process, defects such as pores and cracks can occur at the interface between the substrate and deposited material. In this study, we varied the shape of the pre-machined zone for repair in order to prevent cracks from occurring at the slope surface. After repairs by the DED process, macro-scale cracks were observed in samples that had been pre-machined with elliptic and trapezoidal grooves. In addition, it was not possible to completely prevent micro-crack generation on the sloped interfaces, even in the capsule-type grooved sample. From observation of the fracture surfaces, it was found that the cracks around the inclined interface were due to a lack of fusion between the substrate and the powder material, which led to low tensile properties. The specimen with the capsule-type groove provided the highest tensile strength and elongation (respective of 46% and 571% compared to the trapezoidal grooved specimen). However, the tensile properties were degraded compared to the non-repaired specimen (as-hot rolled material). The fracture characteristics of the repaired specimens were determined by the cracks at the sloped interfaces. These cracks grew and coalesced with each other to form macro-cracks, they then coalesced with other cracks and propagated to the substrate, causing final fracture.

• Journal of Digital Contents Society
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• v.19 no.3
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• pp.479-487
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• 2018

Recently, with the advent of the 4th Industrial Revolution, the diversified industrial base and stable employment market have led to increased concern on the metropolis centered manufacturing. However, To enhance the added value and competitiveness of the manufacturing industry in Seoul, it is necessary to develop specialized smart-based technology and production, and to establish a collaborative system among various businesses in the areas of planning, production, and logistics. Accordingly, I planned a service that is necessary for activation of the urban manufacturing industry in Dongdaemun area of Seoul to enable designers to construct an infrastructure for direct production. The proposed content is a hands-on application that provides information to producers who want to make their own unique products with which they can buy materials from Dongdaemun, Cheonggyecheon, and Uljiro areas.

• Journal of the Economic Geographical Society of Korea
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• v.5 no.2
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• pp.175-185
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• 2002

This study aims to reveal what locational changes of foreign direct investment are prominent in Korea after the economic restructuring programs beginning in 1997. These locational changes would have some potential impacts on the local or national economy. One can expect that concentration in the Seoul Metropolitan Area (SMA) would have intensified after the restructuring because the competitiveness focus would have led foreign investors to high potential areas. An analysis of the data on foreign-invested companies in the manufacturing sector shows that this expectation has come into reality. Within SMA, Seoul shows even bigger changes in the locational share than surrounding areas. Also prominent are increases of the locational share of the SMA in the electrical and electronic companies and in those companies with less than fifty percent investment share. But this pattern is not found distinctly by home country of investment.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.8
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• pp.869-874
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• 2014

It is possible to fabricate a three-dimensional (3D) shape using the solid freeform fabrication (SFF) technology. However, there are several problems in applying conventional SFF technologies to the direct manufacturing of a product. Hence, multimaterial SFF is gaining attention. Moreover, a 3D circuit device that is different from a conventional two-dimensional PCB can also be fabricated using multimaterial SFF. In this study, a hybrid system using fused deposition modeling and direct writing was designed for 3D circuit device fabrication.

• Journal of Arbitration Studies
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• v.29 no.1
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• pp.53-70
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• 2019

This study analyzed some cases of the China International Economic and Trade Arbitration Commision (CIETAC) related to the application of the Contracts for the International Sale of Goods (CISG). As a contracting party of the CISG, China has accumulated a considerable amount of experience in applying CISG through commercial arbitrations. This study sought to understand how CISG is operated in commercial arbitration in China. By analyzing actual cases in China, Korean commercial arbitration can avoid mistakes and further improve. This study of Chinese cases will give some useful information for Korean companies. As defined by the CISG, the applicability can be divided into direct application and indirect application. When China joined the CISG, it made a reservation out of Article 1(1)(b). Korea and China are contracting parties to CISG and CISG is, therefore, directly applied. It is beneficial for Korea to understand how CIETAC is indirectly applied in China then. Some of the results of this study are as follows: First, CIETAC made a correct judgment most of the time on the direct application of CISG. However, there were mistakes in the judgment of the nationality of the parties in a few cases. The parties must clearly define applicable laws when entering into a contract. Secondly, the 2012 "CIETAC Arbitration Rules" was revised so that the "party autonomy" was introduced into Chinese commercial arbitration concerning indirect application. Therefore, the principle of autonomy of the parties was not fully recognized in the past judgments. Instead, the domestic law of China was applied in accordance with the reservation of Article 1(1)(b). Thirdly, China did not explain the application of CISG in Hong Kong, which led to ambiguity in concerned countries. Therefore, it is necessary to confirm the status of CISG in Hong Kong. In addition, Korean companies should clearly define the applicable laws when dealing with Hong Kong companies.

• Korea Trade Review
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• v.46 no.3
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• pp.119-133
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• 2021

After 'Zhou Chuchu (走出去, Go global)' in the early 2000s, and with the 'One-to-One Road' initiative in 2012, China's Overseas Foreign Direct Investment (OFDI) has increased significantly, resulting in high academic interest. The purpose of this study is to analyze the impact of national risks of home country on China's OFDI by using data from 49 countries along the 'One-to-One Road' between 2007 and 2018, and to compare the factors of national risks that attract investment from the world. As a result of the study, market economy companies' perceptions of national risks are mostly negative, so risk acts as a deterrent to investment. On the other hand, national risks of home countries have had positive effects on China's OFDI, which would mean that Chinese investors, mostly state-owned enterprises have a high tendency to invest in regions or countries with high national risks. Other economic factors, such as the size of the investment partner country's market, GNI per capita, and trade openness, had a positive (+) effect, and natural resources had a negative (-) effect on China's OFDI. As dummy variables, FTA, which is an economic and diplomatic factor, SCO, which is a political and diplomatic factor, and bordering which is a geographical factor, were also found to have a positive (+) effect. This study implies the investment pattern of China's OFDI is due to the characteristics of China's unique geopolitical and economic system, and it is judged to be influenced by political and strategic factors, especially the aspects led by state-owned enterprises.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.1
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• pp.11-14
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• 2012

The AlGaN layer has direct wide bandgaps ranging from 3.4 to 6.2 eV. Nowadays, it is becoming more important to fabricate optical devices in an UV region for the many applications. The high quality AlGaN layer is necessary to establish the UV optical devices. However, the growth of AlGaN layer on GaN layer is difficult due to the lattice mismatch and difference thermal expansion coefficient between GaN layer and AlGaN layer. In this paper, we attempted to grow the LED structure on GaN template by mixed-source HVPE method with multi-sliding boat system. We tried to find the optical and lattice transition of active layer by control the Al content in mixed-source. For the growth of epi layer, the HCl and $NH_3$ gas were flowed over the mixed-source and the carrier gas was $N_2$. The temperature of source zone and growth zone was stabled at 900 and $1090^{\circ}C$, respectively. After the growth, we performed the x-ray diffraction (XRD) and electro luminescence (EL) measurement.