• Clean Technology
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• v.24 no.4
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• pp.307-314
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• 2018

In this study, NMO (Natural Manganese Ore), $MnO_2$, and $Mn_2O_3$ catalysts were used in the selective catalytic reduction process to remove nitrogen oxides (NOx) using $NH_3$ as a reducing agent at low temperatures in the presence of oxygen. In the case of the NMO (Natural Manganese Ore), it was confirmed that the conversion of nitrogen oxides in the stability test did not change even after 100 hours at 423 K. The Kinetics experiments were carried out within the range where heat and mass transfer were not factors. From a steady-state Kinetics study, it was found that the low-temperature SCR reaction was zero order with the respect to $NH_3$ and 0.41 ~ 0.57 order with the respect to NO and 0.13 ~ 0.26 order with the respect to $O_2$. As temperature increases, the reaction order decreases as a result of $NH_3$ and oxygen concentration. It was confirmed that the reaction between the $NH_3$ dissociated and adsorbedon the catalyst surface and the gaseous nitrogen monoxide (E-R model) and the reaction with the adsorbed nitrogen monoxide (L-H model) occur.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.94-100
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• 2021

To improve the productivity of cargo containment construction for a membrane LNG carrier, it is important to shorten the installation period and process of the scaffolding system, which is a construction workbench of a cargo containment for a membrane LNG carrier. As an effective method, opinions are being gathered to enlarge the lifting unit from the existing two stages to eight stages. On the other hand, the stresses around the pin and hole will increase significantly because of the increase in lifting load according to the large size of the module. The purpose of this study was to establish a new large module-lifting plan by introducing TRIZ to solve these problems. This study adopted a method to utilize 40 inventive principles, which is one of the various problem-solving tools of TRIZ. First, technical contradictions were derived, the engineering parameters were selected. Second, efficient inventive principles were selected to overcome the technical contradictions using a contradiction matrix. Finally, the general and specific solutions were derived through the selected inventive principle, and structural analysis confirmed that the stress generated in the structure was low. The utility of TRIZ was confirmed by the successful lifting of large modules using the established lifting method.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.7
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• pp.1259-1266
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• 2022

Recently, due to the specialization of structural design standards and evaluation methods, the classification rules are being integrated. A good example is the common international rules (CSR). However, detailed regulations are presented only for the cargo hold area where the longitudinal load is greatly applied, and no specific evaluation guidelines exist for the bow and stern structures. Structural design of the mentioned area is carried out depending on the design experience of the shipbuilder, and because no clear standard exists even in the classification, determining the root cause is difficult even if a structural damage problem occurs. In this study, an engineering-based solution was presented to identify the root cause of representative cases of buckling damage that occurs mainly in the stern. Buckling may occur at the panel wall owing to hull girder bending moment acting on the stern structure, and the plate thickness must be increased or vertical stiffeners must be added to increase the buckling rigidity. For structural strength verification based on finite element analysis modeling, reasonable solutions for load conditions, boundary conditions, modeling methods, and evaluation criteria were presented. This result is expected to be helpful in examining the structural strength of the stern part of similar carriers in the future.

• Journal of the Korean Electrochemical Society
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• v.6 no.3
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• pp.169-173
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• 2003

Electrochemical capacitor made with metal oxide electrode uses rapid and reversible protonation/deprotonation of metal oxide material under the aqueous acidic solution, generally. Electrochemical stability window of aqueous electrolyte-type capacitor is narrow compared to that of organic electrolyte-type capacitor. Electrochemical characteristics of electrochemical capacitor made with metal oxide electrode and lithium or ammonium cation based organic electrolyte were evaluated. Electrochemical capacitor based on $RuO_2$ electrode material and 1M $LiPF_6$ in mixed solvents of EC, DEC, and EMC has anodic and cathodic specific capacitance of 145 and $142F/g-RuO_2{\cdot}nH_2O$, respectively, by using cyclic voltammetry with scan rate of 2mV/sec $g-RuO_2$ in potential range of $2.0\~4.2V(Li|Li^+))$.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2020.11a
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• pp.163-164
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• 2020

Along with the increase in global volume of goods, logistics companies are trying to reduce costs by increasing the size of ships carrying cargo, increasing the efficiency of quantitative equipment at ports, and unmanned electric vehicles on land. Korean naval ports are also facing the same situation as the global trend. In the past, small and medium-sized ships such as FF, PCC, and beheaded eagles are being retired for their longevity, and their positions are being replaced by large ships such as KDX, FFG, and LST-II. In particular, large ships such as Dokdo and the next light aircraft carriers are also being prepared. Unlike general merchant ships, naval ships require periodic inspections and preventive maintenance, so repair piers such as maintenance depots are in operation. The naval maintenance depot mainly uses trailers, trucks, and truck-type cranes to carry out loading and unloading of heavy ships, and the application or development of automation and unmanned equipment performed by the private sector is inadequate, and self-improvement cases are also very weak. This study aims to improve the efficiency of the military logistics system through research on the logistics system such as transport, storage and unloading of heavy goods and maintenance products of naval ships.

• The Korean Journal of Mycology
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• v.21 no.1
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• pp.28-37
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• 1993

An endo-type cellulase, carboxymethyl cellulase(CMCase) IV, was purified from culture filtrate of cellulolytic fungus Penicillium verruculosum. The CMCase IV was acidic glycoprotein having carbohydrate of 13% as glucose and pI value of 4.0. The CMCase IV was 52 KDa of molecular weight in SDS-polyacrylamide gel electrophoresis and have optimum temperature and pH of $50^{\circ}C$ and 5.0 for enzyme activity. The CMCase IV liberated glucose and cellobiose as major products of the enzyme against carboxymethyl cellulose(CMC) and seemed to has transglycosylation activity simultaneously. Cellulase activity staining(zymogram) showed that the cellulase components of P. verruculosum were not aggregated in the medium. P. vrttuculosum mRNA was translated in vitro and translation product by the mRNA coding for CMCase IV was identified by immunoprecipitation.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.119-123
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• 2012

This study presents the effect of oxygen on the $NH_3$ selective catalytic reduction (SCR) by Mn/$TiO_2$ catalyst. The lattice oxygen of catalysts is participate in the low temperature SCR, and the gaseous oxygen directly takes part in the rexoidtion of reduced catalyst. These redox properties of oxygen an play important role in SCR activity and the available capability of lattice oxygen depends on the manganese oxidation state of the catalyst surface. $MnO_2$ species has a higher redox property than that of $Mn_2O_3$ species on deposited $TiO_2$ surface and these manganese oxide states strongly depend on the $TiO_2$ surface area.

• Journal of Korea Port Economic Association
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• v.35 no.3
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• pp.125-150
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• 2019

The Hunchun area is the only development and opening line in Jilin Province and the Changchun-Jilin-Tumen Developmental Plan area, and as a hub area for regional logistics, promoting the logistics competitiveness of the Hunchun area is an important factor in promoting economic development in the Northeast region. The purpose of this study is to derive the factors for activating logistics competitiveness in Hunchun area by applying SWOT analysis and to present them to policy-makers by drawing priority of factors for promoting logistics competitiveness in Hunchun area through AHP survey of Chinese and Korean logistics experts. According to the analysis, the weighting was high in order of opportunity factors and strength factors, and the priority was high in order of factors such as promotion and expansion of One Belt, One Road policies, active support through national policies, construction of international logistics center cities, construction of logistics centers, and supply of bulk cargo. Finally, from a comprehensive perspective, this study presented policy implications such as SO Strategy (Strength-Occupancy Strategy) and ST Strategy (Strength-War Strategy) focusing on the strengths of the Hunchun Region for the strategy of strengthening the logistics competitiveness of the Hunchun area.

• Journal of Navigation and Port Research
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• v.37 no.6
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• pp.581-586
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• 2013

The sea traffic volume in Southwest sea including Wando area have increased every year. However the improvement of the facilities for convenience and safety in port and sea was not enough to meet the increasing demand of traffic and passengers' need. This study dealt with the situations and status of passenger ship traffic system in Wando area. In addition to, questionnaire survey of passenger ship user in Wando area was carried out in order to research the improvement of marine traffic system. On the basis of the result, navigation risks in the area was analysed. The institutional system such as passenger ship fare, enhanced traffic system that can improve marine traffic environment in the area were suggested and examined. The urgent issue was the scattered fishing ground near fairway which makes narrow passage and can cause risky passeger ship's navigation. In the side of passeger ship's operation, the wage of cargo handling was relatively expensive that needed to be improved.

• Korean Journal of Food Science and Technology
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• v.40 no.4
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• pp.382-388
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• 2008

This study examined the nutrient components and physicochemical properties of three new potato cultivars: Gui Valley, Bora Valley, and Gogu Valley, which were acquired from PotatoValley Ltd., and compared them to the Superior cultivar that is widely distributed in food markets. Amino acid, fatty acid, and mineral compositions, as well as total starch, reducing sugar, dietary fiber, vitamin C, and phenolic acid contents were measured. The gelatinization and pasting properties of the potatoes were evaluated using differential scanning calorimetry (DSC) and a rapid visco analyzer (RVA). The three new potato cultivars showed differences for various characteristics compared to the existing Superior cultivar. The Gui valley cultivar has a high potential for processing into items such as French fries or chips, due to its high starch content and low reducing sugar content. Bora valley showed an incredibly high phenolic acid contents, and Gogu valley contained high levels of dietary fiber, minerals, vitamin C, and essential amino acids. Overall, these cultivars are expected to be highly valuable items for develpment and applications of functional food.