• Journal of the Economic Geographical Society of Korea
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• v.15 no.1
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• pp.131-145
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• 2012

During the 1980s and 1990s, most of the old industrial cities of advanced countries have experienced serious de-industrialisation. This has caused many problems, such as economic decline, increasing unemployment, environmental degradation and social unrests. Since the mid-1980s, some of these cities have started to tackle the problems by urban regeneration programs with cultural and artistic activities, new industries, and implementing housing projects. The cities of Newcastle and Gateshead in Northeastern England were the examples of the ones which have created major development projects, such as building condominiums, renovating old factory building, and promoting cultural and art activities. This paper introduces policies and programs of the cities' urban regeneration, analyses their governance structure, and articulates factors contributing to the success of the policies and programs.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.2
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• pp.51-59
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• 2017

Due to the rapid change of global business environment, the growth of China's steel industry and the inflow of cheap products, domestic steel industry is faced on downward trend. The change of business paradigms from a quantitative growth to a qualitative product is needed in this steel industry. In this environment, it is very important for domestic steel distribution companies to secure their competitiveness by selecting good supply companies through a efficient procurement strategy and effective method. This study tried to find out the success factors of steel distribution industry based on survey research from experts. Weighted values of each factors were found by using AHP (analytic hierarchy process) analysis. The weighted values were applied to DEA(data envelopment analysis) model and eventually the best steel supply company were selected. This paper used 29 domestic steel distribution firms for case example and 5 steps of decision process to select good vendors were suggested. This study used quality, price, delivery and finance as a selection criteria. Using this four criterions, nine variable were suggested. Which were product diversity, base price, discount, payment position, average delivery date, urgency order responsibility and financial condition. These variables were used as a output variable of DEA. Sales and facilities were used as an input variable. Pairwise comparison was conducted using these variables. The weighted value calculated by AHP pairwise comparison were used for DEA analysis. Through the analysis of DEA efficiency process, good DMU (decision making unit) were recommended as a steel supply company. The domestic case example was used to show the effectiveness of this study.

• Membrane Journal
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• v.8 no.3
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• pp.148-156
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• 1998

Diffusion dialysis is a membrane process driven by concentration difference using ion-exchange membranes and has been employed for many years for the acid recovery from acidic waste generated in steel, metal-refining and dectro-plating industries. Theoretically acid flux increases in propomon to the acid concentration difference. At acid concentrations higher than 3 N HCl, however, the acid flux had not increased linearly with the concentration difference. In this paper the effects of acid concentrations on diffusion dialysis for hydrochloric acid recovery and the acid transport mechanism in an anion exchange membrane were studied by membrane sorption tests and diffusion clialysis cell tests. The experimental results showed that the molecular diffusion was a major transport mechanism in a low acid concentration range and the proton leakage through an anion exchange membrane played an important role at higher acid concentrations. Also osmotic water transport and membrane dehydration retarded the transport of protons and caused the permeate flux to decrease.

• Journal of the Korean Magnetics Society
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• v.4 no.4
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• pp.326-334
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• 1994

This paper describes the fabrication of the hydrophilic magnetic fluid with high viscosity and its application to oil seal apparatus used with the Nd-permanent magnet. The results are as follows. 1) The ultrafine magnetite particles under the size of $100\;{\AA}$ are first coated by the oleic acid ion and again adsorbed by the hydrophilic D. B. S. ion, and there by hydrophilic magnetic fluid with high viscosity could be made by dispersing them into the ethylene glycol. 2) In development of the oil seal apparatus using magnetic fluid and Nd-permanent magnet, the viscosity and magnetic susceptibility show high when the $Fe_{3}O_{4}$ content is over 50%(g/cc) in the fluid, so that such properties could improve highly the capability of oil seal. 3) The maximum of the resisting pressure of the oil seal using the ethylene glycol base magnetic fluid and the Nd-permanent magnet, is about $50\;g/\textrm{cm}^2$, under the condition of this experiment. Therefore the oil seal may not be suitable for the ship engine and the driving part of the automobile, and thus it needs a lot further complementary reserch. However, it is quite favourable for such an oil seal apparatus as speed reducer under the condition of atmospheric pressure.

• Journal of the Korean Wood Science and Technology
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• v.13 no.4
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• pp.67-72
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• 1985

To improve the bending strength of sawdustboard, verious resin contents of 10, 13, 16, and 19% were applied to the thin shell (face layer) composed with wire net or not. The shell effect of sawdust and wire net composition formed with core sawdustboard were evaluated. Forcusing on the effects of wire net composition and noncomposition including a comparison with chipboard and veneer complyboard, bending properties (Modulus of rupture (MOR), Modulus of elasticity (MOE), Stress at proportional limit ($S_{pl}$). Work to maximum load ($W_{ml}$))were analyzed and discussed. 1. In modulus of rutpute, veneer comply was the highest (621.5 kg/$cm^2$), and next decreasing order was wire net composition (159.1 kg/$cm^2$), chipboard (81.75 kg/$cm^2$), and wire net noncomposition (76.21 kg/$cm^2$) as in modulus of elasticity, work to maximum load, except for stress at proportional limit. 2. The highly significant effects were shown in both wire net composition and noncomposition, at the same time wire net composition exceeded two times of noncomposition throughout resin contents in bending properties. Chipboard was similar to the mean or 16% resin content in noncomposirion. 3. Every board in wire net composition above 10% resin content was beyond 100 kg/$cm^2$ in MOR, minimum allowable strength for structural use according to KS F 3104. In conclusion, the feasibility for improving the bending strength of weak sawdustboard by wire net composed shell was offered.

• Information Systems Review
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• v.6 no.2
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• pp.227-242
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• 2004

With the advent of the digital economy, the business eco-system has been changing from the competition system across individual companies to that of supply chains. Under the rapidly changing business environment, it becomes true that the competitive power of the steel maker depends on the shipbuilding company, an important customer of the steel maker. Accordingly, e-partnering between a steel maker and shipbuilding companies becomes important. Schemes of developing e-partnering are presented as follows: implementation of the inter-communication system, day/sequence order and supply, improvement of infrastructure such as transport, quay etc.

• Journal of Korea Technology Innovation Society
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• v.13 no.4
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• pp.700-716
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• 2010

This paper examines the development of smelting reduction process in POSCO from 1990 to 2007 with the perspective of post catch-up technological innovation. POSCO paid attention to smelting reduction process as a sort of next-generation iron and steel technology, and implemented COREX (coal ore reduction) by the cooperation with V$\"{o}$oest. In addition to this, POSCO started to develop FINEX (fine iron ore reduction) which can use abundant powder ore, and FINEX was developed through model plant, pilot plant, demo plant, and commercial facility. POSCO came up to innovation leader beyond fast follower by securing almost technologies concerning FINEX. The case of smelting reduction process shows various characteristics including appropriate technological choice, successive scale-up, spiral development system, complementary technological cooperation, long-tenn investment, the existence of top management's leadership, and Korean government's support in early stage. This case can be interpreted as a path-revealing innovation in the middle of technological paradigm change.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.145-145
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• 2016

해양환경용 구조물은 극심한 부식 환경에 노출되어 있고 부식손상으로 인한 직간접적 경제적 손실이 발생하고 있는 상황이다. 이에 대한 방식대책으로써 음극방식법이 선박, 교량, 각종 화학장비에 널리 이용되고 있으며, 이러한 산업분야에 가장 흔히 적용되고 있는 음극방식 중 하나가 피방식체에 일정 전류 또는 음극 전위를 인가하는 외부전원법이다. 이는 전도성 부식환경인 해수환경 하에서 철강 및 해양환경용 구조 재료의 내식성을 월등히 향상시킬 수 있기 때문에 설계에 있어서 고급 내식재료 대신 경제적인 상용 재료를 적용할 수 있어 비용 절감효과를 가질 수 있다. 한편 적정 방식전위에서는 부식손상으로부터 강재를 보호하지만, 과방식 전위에서는 취성이 발생함으로써 내구성 감소의 역효과가 나타날 수도 있기 때문에 최적 방식전위의 규명은 반드시 필요하다. 따라서, 본 연구에서는 S355ML강에 대하여 천연해수 용액에서 다양한 정전위를 조건으로 전기화학실험을 실시하여 최적 방식전위를 규명하고자 하였다. 시험편은 에머리 페이퍼로 2000번까지 연마하였고, 아세톤과 증류수로 세척하여 실험하였다. 전기화학(정전위) 실험은 천연해수 속에서 $1.28cm^2$의 면적만을 노출시켜 진행하였으며, OCP로부터 -2.0V까지의 음극분극 곡선을 분석하여 정전위 조건들을 선정하였다. 그리고 외부 직류전원장치를 이용하여 1,200초 동안 다양한 정전위를 인가하였으며, 기준전극은 Ag/AgCl 전극을 이용하였다. 실험 후에는 주사전자현미경과 3D 현미경을 통해 시험편 표면을 관찰하였으며, 그 결과 일부 음극분극 구간에서 강재 표면에 전착물에 의한 뷸균일한 피막이 형성되었다. 또한, 일정 전위구간에서 용해 및 과전압에 대하여 표면손상 정도를 관찰하여, 해수환경 하에서 S355ML강의 최적 방식전위를 규명하였다.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.5
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• pp.153-160
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• 2020

Energy Consumption Predictions for Industries has a prominent role to play in the energy management and control system as dynamic and seasonal changes are occurring in energy demand and supply. This paper introduces and explores the steel industry's predictive models of energy consumption. The data used includes lagging and leading reactive power lagging and leading current variable, emission of carbon dioxide (tCO2) and load type. Four statistical models are trained and tested in the test set: (a) Linear Regression (LR), (b) Radial Kernel Support Vector Machine (SVM RBF), (c) Gradient Boosting Machine (GBM), and (d) Random Forest (RF). Root Mean Squared Error (RMSE), Mean Absolute Error (MAE) and Mean Absolute Percentage Error (MAPE) are used for calculating regression model predictive performance. When using all the predictors, the best model RF can provide RMSE value 7.33 in the test set.

• Journal of the Korean institute of surface engineering
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• v.47 no.2
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• pp.75-80
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• 2014

Nanocrystalline diamond(NCD) films on steel(SKH51) has been investigated using SiC interlayer film. SiC was deposited on SKH51 or Si wafer by RF magnetron sputter. NCD was deposited on SiC at $600^{\circ}C$ for 0.5~4 h employing microwave plasma CVD. Film morphology was observed by FESEM and FIB. Film adherence was examined by Rockwell C adhesion test. The growth rate of NCD on SiC/Si substrate was much higher than that on SiC/SKH51. During particle coalescence, NCD growth rate was slow since overall rate was determined by the diffusion of carbon on SiC surface. After completion of particle coalescence, NCD growth became faster with the reaction of carbon on NCD film controlling the whole process. In the case of SiC/SKH51 substrate, a complete NCD film was not formed even after 4 h of deposition. The adhesion test of NCD/SiC/SKH51 samples revealed a delamination of film whereas that of SiC/SKH51 showed a good adhesion. Many voids of less than 0.1 ${\mu}m$ were detected on NCD/SiC interface. These voids were believed as the reason for the poor adhesion between NCD and SiC films. The origin of voids was due to the insufficient coalescence of diamond particles on SiC surface in the early stage of deposition.