• Journal of Biosystems Engineering
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• v.43 no.3
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• pp.161-172
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• 2018

Purpose: During tillage operations, the selection of a working machine (tool) depends on the soil conditions as well as the type of tillage operation to be performed. The goal of this research was to ascertain the effects of varying working machine parameters of a compact disc harrow on tillage operations under various soil moisture content (SMC) conditions. Methods: The working machine parameters were the disc spacing and machine speed. The tillage parameters under investigation were the soil inversion ratio (SIR), tillage cutting depth (TCD), and soil clod breakage ratio (SCB). To determine the SIR, the areas of the white regions before and after tillage were obtained. The ratio of the difference of the areas of the white regions before and after tillage to the area of the white regions before tillage was considered as the SIR. The SCB was obtained as the ratio of the weight of soil clods after sieving with a mesh size of <0.02 m to the total weight of the soil clods before sieving. The soil TCD was measured using a tape measure at random points after the tillage operation. The resulting data were statistically analyzed in a one-way analysis of variance. Results: The highest soil inversion was achieved when the machine speed was 0.2 m/s with the disc spaced at 0.2 m in the 16.5% SMC. At a 0.4-m/s machine speed and 0.3-m disc spacing the highest soil breakage was achieved in the 26.5% SMC. The highest TCD was achieved at a 0.2-m/s machine speed and 0.2-m disc spacing in the 16.5% SMC. Conclusions: It was concluded that varying the working machine parameters, such as the disc spacing and machine speed, could significantly affect the soil inversion and soil clod breakage; however, it had no significant impact on the TCD.

• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.293-297
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• 2012

A new asiatic lily cultivar 'Point' was derived from a cross between $Lilium$ $concolor$ var. $partheneion$ and 97-5 with orange colored petals made in 2000. The selection and the survey for the flower characteristics were conducted from 2005 to 2008 by using vinyl tunnels and greenhouse at Highland Agriculture Research Center, NICS, RDA. Based on flower color, 'Point' cultivar belongs to orange red group (O-R N30C). There was lots of spots in petal. The flowers had brown stigma and dark brown pollen. The stem color was dark purple. The flowering date was July 8. The plant height was 88.2 cm and flower numbers were 5.4 ea. The length and width of petal were 6.3 cm and 3.2 cm, respectively. The flower size was smaller than that of 'Prato' cultivar. The number of leaves was 12.2 ea. The length and width of leaves were 9.2 cm and 1.1 cm, respectively. The weight and circumference of bulb were about 24.6 g and 11.6 cm, respectively. 'Point' cultivar had resistance to bulb rot disease. The flowering duration was 16.1 days. The preference was good to 4.1 on 5 grades. 'Point' cultivar was registered as a new variety with No. 3446 in Korea Seed and Variety Service on April 2011.

• Journal of the Korean Institute of Gas
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• v.18 no.4
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• pp.76-85
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• 2014

To establish the necessary safety technology in high-pressure toxic gas facilities, especially for the corrosion, which is the main causes of toxic gas accident, this study adopts and investigates the API-581 procedures developed by the American Petroleum Institute (API). And the applicability of the 8-step analytical procedures of consequence analysis in API-581 is discussed, and a method for consequence analysis in high-pressure toxic gas facilities is suggested. Based on the discussion and results, the analytical procedure is simplified as the 6 steps in total for the effective application to high-pressure toxic gas facilities: Step 1 (determination of representative material), Step 5 (determination of release type), Step 6 (determination of phase of fluid), and Step 8 (estimation of damage range) are not applied: Step 3 (estimation of total amount of release) is applied only for the inventory group concept; Step 4 (estimation of release rate) only for the gas release rate; and all of Step 2 (selection of release hole size) and Step 7 (evaluation of post-release response) are applied. In the proposed method, the generally applicable method of CCPS is adopted as alternative method for Steps 5 and 8.

• Korean Institute of Interior Design Journal
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• v.23 no.4
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• pp.157-168
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• 2014

In buildings on the street, indiscriminate redevelopment are being made by overlooking the relationship with surrounding landscape to create their own unique meaning, due to industrialization progressed rapidly with human needs of longing for something constantly. Selection and methods of two plans, conservation and utilization should be required, considering heritage values on industrial buildings which are being lost and aged in this redevelopment higher. The attempt for the use of modern industrial heritage becomes a hot topic, and several experimental challenges are being made. However, there are rather many cases of causing industrial buildings' depreciation and one-size-fits-all reproduction performance as it applies other examples as standards by recognizing the reproduction of modern industrial heritage as one trend, not focusing on the trend of the times or paradigm, what the times want. To minimize these problems, we focus on how to utilize industrial buildings beyond the importance of industrial buildings' reproduction, considering the quality of local residents' life as well as the expected effect obtainable due to security of local identity and reproduction of buildings, focusing on the concept of community design that offers and forms a way of community life as the design of shares based on unspecified individuals' common life. Community design's core can be called to have diversity rather than undifferentiated unity by pursuing whole unification, since local residents become those who plan design and all people participate in it. In addition, community design achieves integration with other fields as an enlarged design area without limiting in an environmental area, by making indigenously natural characteristics combined with cultural factors in one context so that people may understand the flow of the place. The importance of effects acquired from modern industrial heritage's reproduction has well-known, and the attempt for utilizing aged heritage as a new value and a function has constantly been made. Now, it's time to focus on how long it lasts through this method, rather than modern industrial heritage's reproduction itself. There can be a significance in this study in proposing methodological solutions on modern industrial heritage's reproduction, not to cause depreciation of industrial buildings by recognizing contemporary trends and uniform regeneration performance, multifaceted research is needed for creative, effective development on modern industrial heritage which will occur constantly.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.421-427
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• 2009

We successfully fabricated 4.7-inch organic thin film transistors array with $640{\times}480$ pixels on flexible substrate. All the processes were done by photolithography, spin coating and ink-jet printing. The OTFT-Electrophoretic (EP) pixel structure, based on a top gate OTFT, was fabricated. The mobility, ON/OFF ratio, subthreshold swing and threshold voltage of OTFT on flexible substrate are: 0.01 ^2/V-s, 1.3 V/dec, 10E5 and -3.5 V. After laminated the EP media on OTFT array, a panel of 4.7-inch $640{\times}480$ OTFT-EPD was fabricated. All of process temperature in OTFT-EPD is lower than $150^{\circ}C$. The pixel size in our panel is $150{\mu}m{\times}150{\mu}m$, and the aperture ratio is 50 %. The OTFT channel length and width is 20 um and 200um, respectively. We also used OTFT to drive EP media successfully. The operation voltages that are used on the gate bias are -30 V during the row data selection and the gate bias are 0 V during the row data hold time. The data voltages that are used on the source bias are -20 V, 0 V, and 20 V during display media operation.

• Horticultural Science & Technology
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• v.19 no.2
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• pp.140-144
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• 2001

Field investigations were initiated to determine possible new 'ssam' vegetable that could be grown during the summer season in highland. Korean 'ssam' means cooked rice in vegetables. The 'ssam' vegetable is called that those leaves has been used for wrapping at meal. Seventeen leafy vegetables were studied, including chard (Beta vulgaris L. var. flavescens DC.), leaf broccoli (Brassica oleracea L. var. italica), Chinese leek (Allium tuberosum Rottl.), Japanese hornwort (Cryptotaenia japonica Hassk), red leaf mustard (Brassica juncea L.), green leaf mustard (Brassica juncea L.), leaf parsley (Petroselinum crispum Nijim), pakchoi (Brassica campestris L. ssp. chinensis Jusl.) tatsoi (Brassica campestris var. narisoma), kale (Brassica oleracea var. acephala), collard (Brassica oleracea var. acephala), Korean mint (Agastache rugosa O. Kuntze), romaine lettuce (Lactuca sativa L. var. longifolia Lam.), red leaf chicory (Cichorium intybus L. var. folisum), red chicory (Cichorium intybus L. var. folisum), green leaf chicory (Cichorium intybus L. var. folisum), and sprouting broccoli (Brassica oleracea L. var. italica). Date of the first harvest in 1999 was July 10th in chard, leaf broccoli, red mustard, mustard, leaf parsley, pakchoi, tatsoi, kale, collard, Korean mint, red leaf chicory, red chicory, green leaf chicory, and sprouting broccoli. Date of the first harvest for Chinese leek, Japanese hornwort, and romaine lettuce was from the middle of June to the late of August. Based on ratings on marketable yield, we found good leaf shape, taste and yield in chard, red leaf mustard, green leaf mustard, pakchoi, tatsoi, romaine lettuce, red leaf chicory, red chicory, and green leaf chicory. Even though the most of all these vegetables were obtained high scores by test panels in shape, taste and quality, but some of them revealed inadequate leaf size as a 'ssam' vegetable. That problem will be solved by control of harvesting time. On the basis of this observation, chard, red leaf mustard, green leaf mustard, pakchoi, tatsoi, romaine lettuce, red leaf chicory, red chicory, and green leaf chicory were rated as promising 'ssam' vegetable by analysis of profits, adaptation, and quality.

• Journal of Korea Port Economic Association
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• v.37 no.2
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• pp.91-105
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• 2021

The current increasing size of container vessels affects the container port's situation. The containerization has changed the inter-modal handling process, which brought more flexibility and comfortableness in the shipping industry sector. Thus, it is very crucial to analyze the efficiency of container ports in the regional sphere. Such kind of efficiency analysis provide a powerful management tool for port operators and shipping managers in the Mediterranean market, and it also helps to form an information for planning new regional and national port operations. This paper aims to analyze the ports' technical efficiency of Mediterranean major container ports. It is conducted to establish the model of port performance and efficiency through the empirical test of the various factors. Regarding to the panel data collected from the 48 DMUs (decision making units), this study attempts to provide the empirical basis of the port efficiency relative to another factors in the total port performance. Due to the complexity of the various activities carried out at container ports, the study focuses only on the technical efficiency at the level of the Mediterranean container port. Unlike the practice of cross-sectional data analysis, originally established by Charnes et al. (1985), the panel data in DEA window analysis applications are used. The main focus of this study is the relative technical efficiency of 12 container ports from 7 countries in the Mediterranean market. The selection of ports under study is based on their high handling capability and rankings in World Top 100 (Containerization International, 2018).

• Journal of Navigation and Port Research
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• v.42 no.6
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• pp.539-545
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• 2018

In recent years, research on shipping market forecasting with the employment of non-linear AI models has attracted significant interest. In previous studies, input variables were selected with reference to past papers or by relying on the intuitions of the researchers. This paper attempts to address this issue by applying the stepwise regression model and the random forest model to the Cape-size bulk carrier market. The Cape market was selected due to the simplicity of its supply and demand structure. The preliminary selection of the determinants resulted in 16 variables. In the next stage, 8 features from the stepwise regression model and 10 features from the random forest model were screened as important determinants. The chosen variables were used to test both models. Based on the analysis of the models, it was observed that the random forest model outperforms the stepwise regression model. This research is significant because it provides a scientific basis which can be used to find the determinants in shipping market forecasting, and utilize a machine-learning model in the process. The results of this research can be used to enhance the decisions of chartering desks by offering a guideline for market analysis.

• Korean Journal of Heritage: History & Science
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• v.50 no.4
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• pp.222-251
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• 2017

This paper analyzes the characteristics of the ancient tombs discovered in the Gyeongju site and discusses the direction of the excavation. There are six special features of the wooden chamber tomb covered with stone in Gyeongju. First, confirmation of the above-ground type and the underground type burial mound. Second, confirmation of the construction such as the partition of mound and the pile of stone structure. Third, confirmation of the frontal part structure of the protect stone such as pebble-stone layer, boundary stone. Fourth, confirmation of the relationship before and after the mound. Fifth, the circumference and boundary of the confirmed(before 1990s) burial mounds were discovered, resolving the uncertainty. Sixth confirmation of the crowd unit tombs. By summing up these six features, it is possible to clearly divide the individual units and the crowd units of the Silla tombs. Confirmation of individual units and crowd units can clarify the size and scope of the tombs located by the concatenation and overlap. It is possible to get a glimpse of the formation process through the interrelationships between the two sides. The tombs are located in the upper-and-lower layer structure of the tombs and show selective site selection. When this formative process is rearranged, it is understood that the Gyeongju Silla Cemetery is formed through the course of four stages. It is anticipated that it will be possible to make selective projects in the excavation survey based on the confirmation of the individual unit and the crowd unit of the Silla ancient tombs and the formation process.

• Journal of the Korean Society for information Management
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• v.37 no.4
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• pp.1-26
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• 2020

In today's increasingly data-intensive academic environment, data is becoming the foundation of academic communication as a research outcome rather than a research by-product. However, there is a limit to guaranteeing actual data reuse only by expanding the data supply or securing accessibility. In order to overcome this, it is necessary to understand the data reuse behavior and data needs in-depth. Therefore, this study attempted to identify the major data reuse behavior and data needs among researchers. To this end, the authors of KCI papers among the data reuse documents of the Korea Social Science Data Archive (KOSSDA) for the past 3 years were targeted. An in-depth interview was conducted with 12 researchers who accepted the interview. As a result, factors considered when reusing data were personal, economic, technical, and social aspects, and it was found that the data itself was used or contextual information of the data was used depending on the purpose of data reuse. The path to acquiring data is a web-based source of information, and a path through informal communication can also be found. In terms of the data needs, it was found that they prefer English, the United States, and institutional producers. Also they have a clear preference for quantitative data from an interviewer-filled interpersonal interview survey method, rich metadata along with raw data, and data that contains identification information. However, due to the lack of confidence in the value, it is negative for the use of data with controlled access and use, and it is difficult to confirm a clear preference because there is no similar data available for selection in terms of size and freshness.