• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.443-454
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• 2013

Various metal ions (transition and base metals) incorporated MCM-41 catalysts can be synthesized using colloidal and soluble silica with non-sodium involved process. Transition metal ion-typically $V^{5+}$, $Co^{2+}$, and $Ni^{2+}$-incorporated MCM-41 catalysts were synthesized by isomorphous substitution of Si ions in the framework. Each incorporated metal ion created a single species in the silica framework, single-site solid catalyst, showing a substantial stability in reduction and catalytic activity. Radius of pore curvature effect was investigated with Co-MCM-41 by temperature programmed reduction (TPR). The size of metallic Co clusters, sub-nanometer, could be controlled by a proper reduction treatment of Co-MCM-41 having different pore size and the initial pH adjustment of the Co-MCM-41 synthesis solution. These small metallic clusters showed a high stability under a harsh reaction condition without serious migration, resulting from a direct anchoring of small metallic clusters to the partially or unreduced metal ions on the surface. After a complete reduction, partial occlusion of the metallic cluster surface by amorphous silica stabilized the particles against aggregations. As a probe reaction of particle size sensitivity, carbon single wall nanotubes (SWNT) were synthesized using Co-MCM-41. A metallic cluster stability test was performed by CO methanation using Co- and Ni-MCM-41. Methanol and methane partial oxidations were carried out with V-MCM-41, and the radius of pore curvature effect on the catalytic activity was investigated.

• Resources Recycling
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• v.16 no.5
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• pp.19-24
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• 2007

Reefs are the marine structure that can give resting, inhabiting, feeding and nursing spaces for a variety of fishes. Usually artificial reefs are made of cement and steels respectively in Japan as well as in Korea. However since resources deficiency has been getting serious, other materials are taken into consideration for the basic bodies of artificial reefs. About 300 thousand tons of waste agricultural plastic films are generated every yew in Korea, but no effective recycling techniques have been developed. In this sense, artificial reefs made of waste agricultural plastic films are the most representative symbol of the recycled products in the Resource Recycling Era. In particular, since these reefs could be made of the semi-cleaned waste agricultural plastic films that still contain high portion of soil, it is very environmentally friendly not only in manufacturing process but also in using under water. Furthermore they have some evident advantages as follows; 1) high fish swarming effect 2) good initial attachment of the marine growths 3) extremely low corrosion to brine 4) easy adjustment of the gravity 5) economical manufacture, transportation and jettison 6) excellent safety to ecosystem caused by lower elution of toxic substances 7) good recyclable property after application and so on.

• The Journal of Fisheries Business Administration
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• v.40 no.2
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• pp.105-126
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• 2009

This study applies the cointegration theory to analyse the causality of the prices between imported fisheries and domestic fisheries in distribution channel. We've focused on the prices of import, wholesale and retail about the frozen Alaska pollack, hairtail and croaker which take up high portion and are popular among most of the consumers. In process of analysis, the unit root test was adopted to find the stability of time series data prior to the cointegration test. If the time series data was found as stable one in unit root test, we should analyse the VAR model. If unstable, the cointegratioin test was adopeted to find the long-run equilibrium relationship between the data. When the long-run equilibrium relationship was found among the price of the import, wholesale and retail price, the VECM model was adoped. If not, the differenced VAR model was adopted. The main findings of this study could be summarized as follows ; First, according to the result of the analysis on VAR model, time series data of frozen Alaska pollack was found as stable and has causality relationship and close effect was existing among the import, wholesale and retail price. Second, the data of frozen hairtail was found as an unstable one in unit root test and the result of cointegration test showed the long-run equilibrium relationship at lag 1. From the results of VECM model, we could find that the coefficient of error correction is effective, and the sign is negative(-). It means that the existence of adjustment tendency to long-run equilibrium after a short-run deviation. But the short-run causality of the prices were not found except the price of wholesale. Third, according to the results of differenced VAR model, data from frozen croaker did not have the stability and long-run equilibrium. Moreover, it was found that the import price has a weak causality on the retail price. Because of having difficulties in collecting data, the result of this paper could not explain the relationship among the prices of import, wholesale and retail perfectly. However, it more or less contributed to a long-lasted debate on the direction of causality of price-setting in academic research and provided a useful guide for the policy makers in charge of the price-setting of fisheries products as well.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.1
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• pp.17-28
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• 2010

This paper presents a new automatic TFT-LCD image quality optimization system using DSP for the first time. Since conventional manual method depends on experiences of LCD module developers, it is highly labor-intensive and requires several correction steps providing large gamma correction error. The proposed system optimizes automatically gamma adjustment and power setting registers in mobile TFT-LCD driver IC to reduce gamma correction error, adjusting time, and flicker. It contains module-under-test (MUT, TFT-LCD module), PC installed with program, multimedia display tester for measuring luminance and flicker, and control board for interface between PC and TFT-LCD module. We have developed a new algorithm using 6-point programmable matching technique with reference gamma curve and applying automatic power setting sequence. Developed algorithm and program are generally applicable for most of the TFT-LCD modules. It is realized to calibrate gamma values of 1.8, 2.0, 2.2 and 3.0, and reduce flicker level. The control board is designed with DSP and FPGA, and it supports various interfaces such as RGB and CPU. Developed automatic image quality optimization system showed significantly reduced gamma adjusting time, reduced flicker, and much less average gamma error than conventional manual method. We believe that the proposed system is very useful to provide high-quality TFT-LCD and to improve developing process using optimized gamma-curve setting and automatic power setting.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.953-960
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• 2019

The Miller cycle is a diesel engine that has been developed in recent years that it can reduce NOx and improve fuel consumption by reducing the compression ratio through intake valve closing (IVC) time control. The Miller cycle can be divided into the early Miller method of closing the intake valve before the bottom dead center (BDC) and the late Miller method of closing the intake valve after the BDC. At low speeds, the late Miller method is advantageous as it can increase the volumetric efficiency; while at medium and high speeds, the early Miller method is advantageous because of the high internal temperature reduction effect due to the expansion of the intake air during the piston lowering from IVC to BDC. Therefore, in consideration of the ef ects of the early and late Miller methods, it is necessary to adopt the most suitable Miller method for the operating conditions. In this study, a two-stage turbo charge system was applied to four-stroke engines and the process of enhancing the Miller effect through a reduction of the intake and exhaust valve overlap as well as the valve change adjustment mechanism were considered. As a result, the ef ects of fuel consumption and Tmax reduction were confirmed by adopting the Miller cycle with a two-stage supercharge, a reduction of valve overlap, and an increase of suction valve lift.

• Journal of the Korean Institute of Rural Architecture
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• v.1 no.1
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• pp.3-14
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• 1999

It is a important problem that the adjustment of a rural settlementas a unit of rural community, and many number of researcher tackled its. The aim of this paper is to verificate the process of rural con-struction, that is applied the regional resources, and to introduce the situation of attending inhabitants, and their employments as a results of this planning. We chose Odaira hamlets in Oomama town, it is located in Gunma prefecture as an object of this study. Odaira is a small village in the mauntain, and it is composed only 135 families. Odaira is an underpopulated hamlet. It is engaged no lively farming and forestry. Most of inhabitants are commuting to the cities around here. Inhabitants of Odaira who are conscious of the conditions of declining hamlet organized a group to improve it. This group have investigated all around the hamlet as a system of workshop. And they found the resources for sight-seeing, crops as the regional products, and other resources for rural planning under three keywords ; resources for the sight-seeing, the rigional products, and theimprovement of environments. In many resources, most important thing was the existens of a stalactite cave come down as a legend from old time. Local government of Oomama town and the inhabitants tried to explorate of stalactite cave and succesed to excavate it. They have constructed two facilities for management, parkaround the stalactite cave and these have been a new place of work for inhabitants. Arrangement of the rural constructions developed to other items schemed acording to the master plan, like as a camping ground, bungalows, a wet botanical garden, and a park beside a river. These also produced the new places of work for 54 people as a result of this rural planning. The most of them were the aged peoples and the women of farmer. The highest age was 83 years old, he is working at the camping ground. In the employment system at Odaira, people who desire to work and desire to employ both registrate to a commission of management of Odaira, and this commission arrange them in case of needs.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5
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• pp.42-52
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• 2010

This research analyzed the overall issues pertaining to the questions that appear in the professional landscape architect screening system to assess 1he recognition of test-takers when it comes to the test questions in terms of the question objectivity, appropriateness, difficulty level and so forth The purpose of this is to present a set of recommendations so that the screening system can he improved and the professional landscape architect screening system consolidate its position. This in turn can help the professional landscape architect qualification process consolidate its position and improve the status of the landscape area in the industrial field. The research of this study was conducted for the all-round development of Landscape Architecture. The research method was divided into two stages, and a group of experts was leveraged to study subjects that are tested and subjects allocated. A survey was conducted of candidates and certification holders to assess the questions that appear in the test in terms of their level, objectivity, difficulty level, tendency of questions and so forth. Firstly, the study demonstrated that the subjects tested in the professional landscape architect test are different from the testing subjects that are suggested in the enforcement ordinance of the National Technical Professional Law. In addition, o1her problems include the overvaluation of a subject for testing, a lack of objectivity in testing, and difficulty level adjustment of questions. One main reason for many of these kinds of problems is that the questions appeared without thorough review and there is a lack of management concerning the members of the commtittee that develops the question. Accordingly, to make up for these problems, a viable screening system such as the reorganization of subjects that are tested, assigning suitable subjects, securing of question objectivity, and difficulty level of developed questions are necessary.

• The KIPS Transactions:PartD
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• v.17D no.1
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• pp.1-8
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• 2010

Association rule mining techniques enable us to acquire knowledge concerning sales patterns among individual items from voluminous transactional data. Certainly, one of the major purposes of association rule mining is utilizing the acquired knowledge to provide marketing strategies such as catalogue design, cross-selling and shop allocation. However, this requires too much time and high cost to only extract the actionable and profitable knowledge from tremendous numbers of discovered patterns. In currently available literature, a number of interest measures have been devised to accelerate and systematize the process of pattern evaluation. Unfortunately, most of such measures, including support and confidence, are prone to yielding impractical results because they are calculated only from the sales frequencies of items. For instance, traditional measures cannot differentiate between the purchases in a small basket and those in a large shopping cart. Therefore, some adjustment should be made to the size of market baskets because there is a strong possibility that mutually irrelevant items could appear together in a large shopping cart. Contrary to the previous approaches, we attempted to consider market basket's size in calculating interest measures. Because the devised measure assigns different weights to individual purchases according to their basket sizes, we expect that the measure can minimize distortion of results caused by accidental patterns. Additionally, we performed intensive computer simulations under various environments, and we performed real case analyses to analyze the correctness and consistency of the devised measure.

• The KIPS Transactions:PartD
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• v.18D no.4
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• pp.225-236
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• 2011

Various applications of LBS (Location Based Services) are being developed to provide the customized service depending on user's location with progress of wireless communication technology and miniaturization of personalized device. To effectively process an amount of vehicles' location data, LBS requires the techniques such as vehicle observation, data communication, data insertion and search, and user query processing. In this paper, we propose the historical location index, GIP-FB (Group Insertion tree with Flexible Buffer Node) and the flexible buffer node technique to adjust the cost of data insertion and search. the designed GIP+ based index employs the buffer node and the projection storage to cut the cost of insertion and search. Besides, it adjusts the cost of insertion and search by changing the number of line segments of the buffer node with user defined time interval. In the experiment, the buffer node size influences the performance of GIP-FB by changing the number of non-leaf node of the index. the proposed flexible buffer node is used to adjust the performance of the historical location index depending on the applications of LBS.

• Health Policy and Management
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• v.17 no.3
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• pp.1-25
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• 2007

Relative value scales introduced in 2001 remarkably improved health insurance fee schedule, but current relative value scales have many problems. In the beginning the government intended to introduce 'resource based relative value scales(RBRVSs)' like USA, but political adjustment of RBRVS studied in 19.17 weakened the relationship between relative value scale and resource consumption. So unbalance of health insurance fees are existing till now. Also relative value was not divided to physician work and practice expense, and malpractice fee was not divided separately. To correct the unbalance of current relative value scales, the refinement project of health insurance relative value scales started in 2003. The project team divided relative value scales into three components, which are physician work, practice expense, malpractice fee. Physician work was studied by professional organizations like Korean medical association. To develop the practice expense relative value, project team organized clinical practice expert panels(CPEPs) composed of physicians, nurses, and medical technicians. CPEPs constructed direct expense data like labor costs, material costs, equipment costs about each medical procedures. The practice expense relative values of medical procedures were developed by the allocation of the institution level direct & indirect costs according to CPEPs direct costs. Institution level direct & indirect costs were collected in 21 hospitals, 98 medical clinics, 53 dental clinics, 78 oriental clinics, and 46 pharmacies. The malpractice fee relative values were developed through the survey of malpractice related costs of hospitals, clinics, pharmacies. Putting together three components of relative values in one scale, the final relative values were made. The final relative values were calculated under budget neutrality by medical departments, that is, total relative value score of a department was same before and after the revision. but malpractice fee relative value scores were added to total scores of relative values. So total score of a department was increased by the malpractice fee relative value score of that department This project failed in making 'resource based' relative value scales in the true sense of the word, because the total relative value scores of medical departments were fixed. However the project team constructed the objective basis of relative value scale like physician's work, direct practice expense, malpractice fee. So step by step making process of the basis, the fixation of total scores by the departments will be resolved and the resource based relative value scale will be introduced in true sense.