• The Journal of the Korea Contents Association
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• v.16 no.4
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• pp.179-194
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• 2016

The purpose of this study is to find out how the reconstructed textbook for vocational high school students influences on students' scholastic achievement and affective domain when it is used in the class of vocational high school. To tackle the study problems, the researcher chose two classes of the first grade in G commercial high school and gave lessons to each of the two classes; one class, as an experimental group, was taught with the reconstructed textbook and the other, as a comparative group, was taught with the original textbook. The following results are derived from the study. First, it turned out in the post academic achievement test result, there is no significant difference between the experimental group and the comparison group, by significant level; .05. However, the prior academic achievement test result shows that the average of the comparison group is 0.44 points higher than the average of the experimental group, while the post test result shows that the average of the experimental group is 1.96 points higher than the average of the comparison group. Second, it turned out by the post affective domain test result, there is no significant difference between the experimental group and the comparison group, by significant level; .05, and any significant difference did not occur in all five areas. However, the whole point of the affective domain and the points of each area of experimental group are higher than those of the comparison group, and the degree of improvement in experimental group is also greater than that of the comparison group. In conclusion, the effectiveness of utilizing a reconstructed textbook in vocational high school math class can be expected in the long term.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.490.2-490.2
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• 2014

Since the general solar cells accept sun light at the front side, excluding the electrode area, electrons move from the emitter to the front electrode and start to collect at the grid edge. Thus the edge of gridline can be important for electrical properties of screen-printed silicon solar cells. In this study, the improvement of electrical properties in screen-printed crystalline silicon solar cells by contact treatment of grid edge was investigated. The samples with $60{\Omega}/{\square}$ and $70{\Omega}/{\square}$ emitter were prepared. After front side of samples was deposited by SiNx commercial Ag paste and Al paste were printed at front side and rear side respectively. Each sample was co-fired between $670^{\circ}C$ and $780^{\circ}C$ in the rapid thermal processing (RTP). After the firing process, the cells were dipped in 2.5% hydrofluoric acid (HF) at room temperature for various times under 60 seconds and then rinsed in deionized water. (This is called "contact treatment") After dipping in HF for a certain period, the samples from each firing condition were compared by measurement. Cell performances were measured by Suns-Voc, solar simulator, the transfer length method and a field emission scanning electron microscope. According to HF treatment, once the thin glass layer at the grid edge was etched, the current transport was changed from tunneling via Ag colloids in the glass layer to direct transport via Ag colloids between the Ag bulk and the emitter. Thus, the transfer length as well as the specific contact resistance decreased. For more details a model of the current path was proposed to explain the effect of HF treatment at the edge of the Ag grid. It is expected that HF treatment may help to improve the contact of high sheet-resistance emitter as well as the contact of a high specific contact resistance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.418-429
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• 2012

In this study we surveyed the packaging preferences of consumers for Korean rice cakes as current commercial products in Korea. The questionnaire was developed from a preliminary investigation of typical rice cake packaging patterns and sent to 2332 residents in Korea by random sampling mail. The questionnaire contained questions on the preferences of interior design in packaging, opening methods, individually separated types, printing position, packaging methods, and packaging materials such as paper and plastic. There were responses from 304 residents. The collected data was analyzed by an SPSS package program. Most of the packaging used for Korean rice cakes was plastic (58.9%) which was used for packaging materials and stretch wrap (42.9%) as packing methods. The results showed the preference was the perforated line type used by hand for opening a packaging and interior packaging design with 2~3 partitions. Most respondents expressed an interest in using individual packaging and having printing directly on the packaging. Also, the respondents preferred the packaging design that let them see the contents of a package. Based on the results of the questionnaire, this paper suggested that most consumers would prefer to choose a packaging system with a partition design in a plastic container, individually separated products, and a transparent container for Korean rice cakes. The results of packaging preferences could provide important information for suitable packaging development for Korean rice cakes. Further research should be conducted to improve the shelf life of Korean rice cakes with functional packaging systems such as modified atmosphere packaging or anti-microbial packaging.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.192-199
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• 2016

This article examines the location strategies of coffee franchises in Gyeonggi province. Due to its large population, broad area, and diverse industrial structure, Gyeonggi province is an ideal dataset for empirical testing of the location strategies. We collect the addresses of five major coffee franchises stores, convert them into geographic coordinates using Google Maps Geocoding API, and compute Haversine distances both between stores of the same franchise and between stores of different franchises. This novel approach leads to three discoveries. First, coffee-consuming age population is positively related to the number of stores and more strongly for commercial areas with a large floating population. Second, one third of Starbucks stores have another Starbucks store within a radius of 300m, which empirically confirms the 'Focused Destroy Strategy' of Starbucks that has multiple stores in central business districts. Third, for 80% of Starbucks stores, we can find Ediya stores within 500m, which supports Ediya's 'Next-to-Starbucks Strategy'. Our research methods can be efficiently applied to the analyses of other retail businesses such as convenience stores, fast food restaurants, and mobile phone shops.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.596-603
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• 2020

'Electro-Mechanical Brake (EMB) is a novel braking system for automobiles and railway vehicles, and research in this area is actively underway. The current braking system for railway vehicles generates a braking force using a pneumatic cylinder, but the EMB system generates the force through a combination of an electric motor and gears. In this study, the design of an EMB system that meets the domestic standards was conducted through the finite element modeling and fatigue analysis of an eccentric rotating shaft-based EMB system capable of generating a high clamping force. At this time, to improve the accuracy of fatigue analysis, three types of fatigue test specimens, which were subjected to the same heat treatment as the materials used in the prototype, were produced, and the fatigue tests were performed for each material. The fatigue properties (S-N curves) were obtained from the fatigue test results for each material and reflected in the analysis model. The results of fatigue analysis confirmed that the design of the EMB prototype could satisfy the maximum commercial braking/relaxation of 530,000 times, which was the endurance life condition for domestic railway vehicles. In addition, based on this design, a prototype will be manufactured, and endurance testing will be completed to demonstrate the durability characteristics of the developed prototype.

• Journal of the Institute of Convergence Signal Processing
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• v.19 no.3
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• pp.139-146
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• 2018

Underwater acoustic communication can be applied to various area such as scientific, commercial and military survey using Autonomous Underwater Vehicles and Unmanned Underwater Vehicles. Underwater communication is studying very actively by advanced country like United States. But differ from wireless communication in the air, underwater acoustic communication has some difficult problems, ISI(Inter Symbol Interference) due to multipath and limit of transmission bandwidth due to slow propagation of sound wave. In this paper, SC-FDE and OFDM transmission system for the cancellation of ISI in conjunction with underwater acoustic channel modeling are applied to the underwater simulation of communication. The performance of these methods in the simulation guide to possibility of adopting in underwater acoustic communication algorithm. For this purpose, we compare SER performance of SC-FDE with that of OFDM for modelled underwater channel. Underwater channel is generated by Bellhop model. Simulation results show above 5dB SNR gain at 10-3 SER. And it demonstrate SC-FDE is efficient method for underwater acoustic communication.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.393-399
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• 2003

The purpose of this study was to investigate the preferred methods for making summer kimchi as a basic research of making commercial kimchi. Questionnaire were collected from 590 housewives nationwide in Korea, and the data were analyzed by SPSS program. The results were as follows: (1) The average salting time of Chinese cabbage was 3~5 hrs when the combined method of dry and brine salting was used, regardless of the region. (2) Seven jeotkals (salt-fermented fishes) including anchovy, anchovy juice, shrimp, northern sand lance juice, hair-tail viscera, flatfish and yellow corvenia were mainly used in kimchi. Among them, anchovy and anchovy juice jeotkals were preferred to all others in Southern area (Busan, Gwangju, Gyeongnam, Gyeongbuk, Jeonnam), while shrimp jeotkal in Seoul, Gwangju, Jeonbuk, Chungnam and Jeju, and northern sand lance juice jeotkal in Daegu, Daejeon and Gyeonggi, respectively. In most regions, however, blending type of 2 jeotkals was used in kimchi. (3) Eleven ingredients such as red pepper, garlic, ginger, green onion, radish, leek, onion, carrot, sugar, sesame and MSG were used as basic components for making kimchi. In particular, MSG was used as a basic ingredient regardless of region and age. However, a standard taste for making kimchi was depended on housewife in this study.

• Journal of the Korean Geographical Society
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• v.31 no.3
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• pp.558-576
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• 1996

Since 1978. China has progressed her reforms of her economy. In this process, refroms in rual area have been operated with top priority. The system of collective economy had been changed into that of private economy. Rural farming and land-use system had been changed also. The household responsibility system took the place of a People's Commune. That was the system that could inspire farm-household with a will to work, and hence, increase the productivity of agriculture. However, with the developement of market mechanism in the later 1980s, that system got inadequate to new situation. For instance, incentives of a will to work slowly decreased, agricultural productivity did not increase, and labor forces were tremendously transferred to non-agricultural sector. This situation created the demand for a new system of rural land policy and use. This paper intends to describe changes of new system of land use in rual China. Those changes are as follows. 1. The system of land-circulation has been spread widely. 2. 'Liangtianzhi' (the system of two kind land-use) divided the land into two kinds, 'kouliangtian' (the land of food) and 'zerentian' (the land of obligation). The one is allocated in proportion to the per capita, and to support farm-household' and function, the other is allocated in proportion to the labor force, in order to increase the commercial function of land. 4. 'Guimojingying' (management of scale): For overcomint the disadvantage of dispersal of land, the relative concentration of land was required. 4. 'Gufenzhi' (a joint-stock system) is practised for the purpose of establishing clear-cut lines of land ownership. 5. 'Sihuangpaimai' (auction the use right of four kinds of wasteland) is for full-using of the wasteland. It can be apprehended that these systems and policies were the process of adaption to market mechanism. In these, rural China could escape form the disorder due to rapid changes, and overcome the existing contradiction.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.6
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• pp.98-116
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• 2006

For the next two decades the civil aviation industry is expected to grow. Both Airbus and Boeing predict a delivery of almost 20,000 new Large Civil Aircraft (LCA). LCA is defined as a large civil jet aircraft with 100 seats or more. Airbus offers the Superjumbo, A380 (>555 seats), while Boeing presents the Dreamliner, B787 (200 – 300 seats). Their philosophies are very different. In the wake of B787, Airbus intends to offer a new aircraft, A350, as the competitor against B787, with the same engines developed for B787. The U.S. government pushed by Boeing, on the day of October 6, 2004, filed a suit against Airbus for wrongful subsidy to the World Trade Organization (WTO). A brief overview is given on the LCA development status in the world commercial aircraft market. Since there have been little changes in engine and avionics manufacturers in the LCA industry, the airframe area only is the object of this study. An analysis is carried out to find out the differences in development and marketing strategies of two major LCA manufacturers, Airbus and Boeing. The authors predict that Boeing will recapture its No. 1 position soon, while the leading edge in technology may be slipped away from Boeing.

• Research in Plant Disease
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• v.19 no.1
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• pp.55-59
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• 2013

The purpose of this experiment was to investigate the development of new spot disease on the leaf and stem of rosemary (Rosmarinus officinalis) in commercial greenhouses at Jeonju and Namwon in Korea. Incidence of target spot on rosemary was higher at the end of the rainy season with high humidity. Those symptoms were black ring spots (3-5 mm in diameter) and withering on green leaves and stems. Conidiophores and conidia were formed on the infected tissue in moist chamber and conidia were shown as the cylindrical and oval types in chain, ranged from 55 to $275{\mu}m$ in length, and 7 to $14{\mu}m$ in width. Conidia with eight to ten pseudosepta were formed on the conidiapore. The optimum growth temperature of isolates was $30^{\circ}C$ on the PDA medium under the dark condition. In the pathogenesis test, the target spot and withering symptoms were appeared on the leaves and stems 3 days after inoculation showing similar symptoms compared to those of in nature. The same fungus was re-isolated from infected lesion, indicating that Corynespora cassiicola caused leaf target spot and twig blight on rosemary. The rDNA ITS nucleotide sequences of the pure cultured isolate from the diseased area on rosemary showed 100% similarity to the sequences of C. cassiicola available in the GenBank database (JQ595296, JQ595297, FJ852715 and AY238606). Therefore, we report that the target spot of leaves and stems in rosemary was caused by C. cassiicola.