• Journal of the Korean Ceramic Society
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• v.39 no.12
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• pp.1138-1142
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• 2002

Slag cement and supersulfated slag cement were fabricated by mixing blast furnace slag and ordinary portland cement and adapted to solidify/stabilize heavy metal contained hazardous waste sludge. In case of slag cement, it showed continuous increase of their compressive strengths, which is attributed to the formation of the C-S-H, ettringite and monosulfate with STS sludge. However, BF and COREX sludge has a different shape and composition. therefore, adequate compressive strength could not be achieved with this slag cement. In case of the mixture of the each sludge like the STS-BF or the STS-COREX, the compressive strength over the standard level for disposing the wastes could be obtained with slag cement. The supersulfated slag cement that contain accelerators was very effective in solidifying the COREX sludge, which was difficult to solidify using different cement and obtained high compressive strength only for 3 days.

• Journal of the Korean Ceramic Society
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• v.39 no.12
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• pp.1133-1137
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• 2002

The cement for solidification of the toxic waste was fabricated using a mixture of the waste concrete powder and blast furnace slag in the ratio of 1:1 and its hydrate morphology and compressive strength of the sample were evaluated in order to apply to the solidification of the COREX sludge. The X-ray diffraction analysis of the sample which prepared by the addition of 10% Portland cement and hemihydrate showed the presence of $Ca(OH)_2$, ettringite, gel-phase and C-S-H hydrate. Compressive strength of the sample exhibited enough high to use as a solidification cement. The strength of the sample was over 140 kgf/$m^2$ in 7 days in case of solidification of the COREX sludge and the sample possess sufficient morphology for the solidification and stabilization of the waste sludge.

• 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.

• Resources Recycling
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• v.10 no.3
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• pp.37-42
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• 2001

Current iron and steelmaking operation was re-evaluated on the basis of slag engineering technology to optimize slag operations. In blast furnace process, increase in the basicity of slags (C/S) could obtain progressed fluidity and hot metal quality. COREX process would be stabilized in view of slag fluidity and hot metal quality by reducing input content of $SiO_2$and $A1_2$$O_3$In STS-AOD process, addition of small amount of lime could improve refining capacity of the slag; also calcium aluminate flux could be taken into account as a potential substitute for fluorspar, without degradation of operation efficiency and steel quality.

• Journal of Radiation Protection and Research
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• v.14 no.1
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• pp.34-45
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• 1989

The habitability of a reactor control room in a French 1300 MWe P'4 type PWR has been evaluated through the exposure dose assessment for the reactor operator following a Loss of Coolant Accident. The main hypotheses adopted in this evaluation are based on the French Standard Safety Analysis Report. A simple computer program, named COREX(Control Room EXposure), was developed to calculate : the time-integrated radioactivities released from the reactor building, the volume factors for radionuclides concerned and the resulting time-integrated external whole body and internal thyroid doses to the reactor operators staying in the control room up to 30 days following the LOCA. The results obtained in this study, on the whole, well agreed with those proposed by the EDF(Electricite de France) except for the case of the whole body exposure, which was attributed to the differences in the volume factors for the radionuclides concerned.

• Journal of Environmental Science International
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• v.18 no.2
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• pp.187-195
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• 2009

This study was investigated to control the corrosion and scale at the cooling water system in steel works. Laboratory and field tests were performed for the indirect cooling water system of plate mill. Throughout the experiment, various factors such as leakage of pipes, heating rate and capacity, and the reaction between existing and substitute inhibitors were carefully monitored. The results showed that the harmful effect of high temperature could be minimized, and satisfactory corrosion/scale controls were effectively achieved using inhibitor, even at the increased temperature of $80^{\circ}C$. The batch and field tests in the gas scrubbing cooling water system of blast furnace and cooling water system of corex plant indicated that the new inhibitor was more effective for the prevention of corrosion and scale than the existing one.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.811-813
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• 2008

To see the effect of magnesium on adhesion to natural zeolites, a series of batch tests were performed in this research. Mixed bacteria were sampled from the digestion tank at a local sewage treatment plant in Seoul. Magnesium-zeolites were synthesized by mixing natural zeolites with 0.096 M, 0.24 M, and 0.48 M of MgCl2 solution. For comparison, manganese and trivalent ferric zeolites were also prepared. Two grams of 0.2 mm $\sim$ 0.3 mm sized zeolites(non-treated, Mg, Mn and Fe(III) treated zeolites) and 20 mL of water were mixed in a Corex 25 mL tube. Five milliliters of culture solution including bacteria was added to the tube. The tubes were equilibrated in a shaking incubator at mesophilic temperature $(30{\pm}2^{\circ}C)$. The bacterial concentrations were measured with a Microluminometer (New Horizons 3550i) and total organic carbon (TOC) spectrophotometer (Multi NC-3100).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.317-320
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• 2016

In embedded system, if firmware code is opened by other company, must devise hardware copy prevention. That guard valuable product. Not used security IC, Suggested platform is source code open method that prevent core code and hardware copy. And that open firmware code for other company programmer. Suggest system security platform based on Corex-M3. that consist of IAP(In-application programing) and APP(Applicataion). IAP contain core code and security confirm code. APP is implement by other company developer using core function prototype.

• Journal of the Korean Ceramic Society
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• v.39 no.7
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• pp.680-686
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• 2002

The solidification/stabilization mechanism of each cementious material was investigated. It was found that when $C_3$S was hydrated , the Pb element could be transferred to the insoluble Ca[Pb(OH)$_3$.$H_2O$]$_2$and the Cr element to the CaCr $O_4$$H_2O$. The addition of heavy metal tends to delay the hydration until initial 7 days. The Pb element as also delayed the hydration and the Cr element was substituted for the ettringite. On the occasion of the hydration of $C_4$ $A_3$ $S^{S}$, the Pb and Cr ions were solidified/stabilized by the substitution into the ettringite and/or monosulfate. Leaching of the Pb, Cr and Zn elements in the solidified material was extremely little, indicating that heavy metals were effectively solidified/stabilized in the hydrated cementious materials. Solidification/stabilization of heavy metal ions in the industrial wastes such as the STS, BF and COREX sludge was investigated. In case of the mixing ratio of cement and slag was 3 : 7, leaching of hazardous heavy metal ions was very little, indications that the solidification and stabilization was very successful.l.

• Journal of Nutrition and Health
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• v.39 no.8
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• pp.721-727
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• 2006

This study was conducted to investigate the effects of Aralia elata, Acanthopanacis cortex and Ulmus davidiana water extracts on blood hemoglobin, $HbA_{1c}$, levels and biomarkers in the streptozotocin (STZ)-induced diabetic rats. Male Wistar rats divided into normal and diabetic groups. The diabetic groups subdivided into the control group (DM) and Araliaceae water extracts supplemented groups: Aralia elata (AE), Acanthopanacis cortex (AC) and Ulmus davidiana (UD). The extracts were supplemented in diet base on 11.42 g of raw Araliaceae/kg diet for 7 weeks. The diabetes was induced by injecting 572 (55 mg/kg B.W., i.p.) once 2 weeks before sacrifying. Relative weights of liver were significantly lowered in the DM group compared to the normal group, whereas those of kidney and heart were significantly increased in the DM group. Supplementation of the Araliaceae water extracts improved reduced liver weights in STZ-induced diabetic rats. Blood glucose level was significantly higher in the DM group than in the normal group, whereas insulin contents were significantly lowered in the DM groups. However, these parameters were normalized in the An, AC and UD supplemented groups, respectively. Blood hemoglobin and $HbA_{1c}$ levels were significantly higher in the DM group than in the normal group. When all of Araliaceae water extracts were supplemented to the diabetic rats lowered hemoglobin and $HbA_{1c}$ levels. Red blood cell, white blood cell and Lymphocyte were significantly higher in the DM group than in the normal group. The supplementation of Araliaceae family water extracts significantly lowered these parameters compared to the DM group. MCV, MCH contents were declined in the DM group, while the supplementation of Aralia elata, Acanthopanacis cortex and Ulmus davidiana water extracts elevated of these contents in STZ-induced diabetic rats. Accordingly, these results indicate that Aralia elata, Aeanthopanacis corex and Ulmus davidiana water extracts would seem to improve the blood biomarkers in STZ-induced diabetic rats.