• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.469-487
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• 2007

Grain-Size Trend Analysis is the methodology to identify net sediment transport pathways, based on the assumption that the movement of sediment from the source to deposit leaves the identifiable spatial pattern of mean, sorting, and skewness of grain size. It can easily be implemented with low cost, so it has great potentials to contribute to geomorphological research, whereas it can also be used inadequately without recognition of its limitations. This research aims to compare three established methods of grain-size trend analysis to search for the adequate way of application, and also suggest the research tasks needed in improving this methodology 1D pathway method can corporate the field experience into analyzing the pathway, provide the useful information of depositional environments through X-distribution, and identify the long-term trend effectively. However, it has disadvantage of the dependence on subjective interpretation, and a relatively coarse temporal scale. Gao-Collins's 2D transport vector method has the objective procedure, has the capability to visualize the transport pattern in 2D format, and to identify the pattern at a finer temporal scale, whereas characteristic distance and semiquantitative filtering are controversial. Le Roux's alternative 2D transport vector method has two improvement of Gao-Collins's in that it expands the empirical rules, considers the gradient of each parameters as well as the order, and has the ability to identify the pattern at a finer temporal scale, while the basic concepts are arbitrary and complicated. The application of grain sire trend analysis requires the selection of adequate method and the design of proper sampling scheme, based on the field knowledge of researcher, the temporal scale of sediment transport pattern targeted, and information needed. Besides, the relationship between the depth of sample and representative temporal scale should be systematically investigated in improving this methodology.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.306-316
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• 2006

In this study, the effect of the shade level, water flow rate applied to the shades and the temperature of water on the greenhouse cooling was investigated depending on the shade level of 0, 35, 55, 75%, and water flow rate and water temperature by the test on the small wooden frames to find out the low cost cooling method. With increasing of the dry bulb temperature of outside air, the dry bulb temperature in the wooden frames increased. For the frames with the shade and water, inside temperatures of the frames were lower of -0.2$\sim$-1.2$^{\circ}C$ than the temperature of the outside air and higher than the water temperature. For the frames without water, inside temperatures of the frames were higher of 1.7$\sim$4$^{\circ}C$ than the outside and not affected by the shade level very much. The water flow rate and the temperature of the water were not the important factors to decrease the inside temperatures in the frames. The black globe temperature became lower with increasing of shade level. The shade frames with water curtain showed the best cooling effect because of reducing thermal radiation and cooling the plastic film cover. The surface temperatures of the plastic film cover for the water supplied modules became lower with increasing of the shade level. The relative humidity was decreased with the dry bulb temperature in the frame increasing and not affected by the dry bulb temperature of the outside air for the frames with the shade and water.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.3
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• pp.75-86
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• 2017

The development of web technologies and the generalization of smartphones have dramatically increased the number of social media users using the Internet. As a result, companies are perceived social media as a major marketing tool and operate a variety of SNS channels. In particular, start-ups conducting businesses with limited resources, social media is being used as an effective marketing tool to meet many potential customers at a low cost. Among them, facebook is the most used channel in the world and plays an important promotional tool not only in overseas but also in marketing activities of domestic start-ups. The purpose of this study is to analyze the relationship between satisfaction and purchase intention according to four personal characteristics of users who use social media contents and to measure the mediating effect of satisfaction on the relationship between content type and purchase intention. To this end, we classified into three types based on the previous research, and social media content is provided to 200 fans of Minbak Danawa(Minda), one of representative start-ups related to accommodation, The questionnaires were conducted for 3 weeks, and a total of 145 copies were collected. All the collected questionnaires were used for statistical analysis through SPSS 18.0. The empirical results show that all three types of content, such as task-oriented, self-oriented, and interaction-oriented, have a significant effect on the satisfaction level. Among them, it is confirmed that the satisfaction level plays a mediating role on the relationship between task-oriented contents and purchase intention. And the user 's personal characteristics showed a partially moderate effect on the satisfaction according to the content type. Therefore, social media content provided by corporations has an important effect on consumer satisfaction and purchasing, in order for start-up to prevail in the market, it is necessary to have an operational strategy to communicate with customers continuously through systematic contents analysis and planning. The result of this study suggests effective ways to build a social media marketing strategy for start-ups and suggests ways to utilize contents considering the characteristics of internet users.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.308-316
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• 2015

This study was conducted to investigate the situation of ICT apply to plastic greenhouse, and the results be apply to design of new one. A CFD analysis were conducted to monitering the ventilation and energy saving of the single span greenhouse newly designed. The causes of delay to apply ICT to plastic greenhouse are the high cost for installation(24%), insufficiency of after services(19%), often disorder(16%), unskillful management of soft ware(15%), insufficient ICT efficiency(13%) and unsatisfying of income increase(12%). The parts of problem occurred in ICT plastic greenhouse are the structure, actuator, environmental control system and sensor(approximate 14%, respectively), remote control technique(13%), plant management technique(12%), energy saving technique(10%) and utilization of software(8%). In the condition of lateral window closed, the average wind speed changed to slow, but it was faster in the condition of leeward side window opened than in the condition of lee and winward side window opened. The air movement in the condition of lateral window closed occur by air moving fan not by out air. It is not affect the room temperature but effective the uniformity of room temperature. The average temperature of low height greenhouse was uniform than high height one. The average temperature in condition of 3rd curtain opened become same with outside temperature after 2 hours, but take more 5 hours in condition of 3rd curtain closed.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.279-287
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• 2020

Recently, interest in radiation protection is increasing because of the occurrence of accidents related to exposure dose. So, the nuclear safety act provides to install the shields to avoid exceeding the dose limit. In particular, when the worker conducts the non-destructive testing (NDT) without the fixed shielding structure, we should monitor the access to the workplace based on a constant dose rate. However, when we apply for permits for NDT work in these work environments, the consideration factors to the estimation of the distance and exposure dose are not legally specified. Therefore, we developed the excel model that automatically calculates the distance, exposure dose, and cost if we input the factors. We applied the assumption data to this model. As a result of the application, the distance change rate was low when the thickness of the lead blanket and collimator is above 25 mm, 21.5 mm, respectively. However, we didn't consider the scattering and build-up factor. And, we assumed the shape of the lead blanket and collimator. Therefore, if we make up for these limitations and use the actual data, we expect that we can build a database on the distance and exposure dose.

• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.103-110
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• 1994

Since the supply of the Southeast Asian tropical timber decreases and its price steeply increases in the international lumber market, door and window frame manufacturers in this country are eagerly searching for their substitutes. This is the first step to replace Southeast Asian tropical timber by low grade North American softwoods, whose reliable and steady supply is expected, but their appearances are not as good as the tropical timber. In this study, knot distribution on the softwood boards and their warp were examined The yield and production cost were also calculated. The average numbers of knots on a door frame were 7.2 for Douglas-fir and 3.4 for Western hemlock. Only 11% of the knots of Douglas-fir door frames are larger than 5cm in diameter, while are 35% of the knots of Western hemlock. The deformations of door frames, after 2 months air-drying, were measured with a warp table. The deformations of Western hemlock door frames were mostly less than 6mm, while those of Douglas-fir distributed in the range of 0.5 and 9.5mm. The yield of Western hemlock is higher than that of Douglas-fir. It can be concluded that the door frames made of the softwoods are compatible with those made of the tropical timber in most aspects except appearance.

• Journal of the Speleological Society of Korea
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• no.63
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• pp.1-8
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• 2004

The non-magnetic materials with non-conductive showing high structure dispersity were developed on the base of natural quartz and lava-scoria which was collected from Je-ju island in Korea, and treated by methane-chemical technology those were obtained novel properties of magnetization through the analyzing. Depending on the processing conditions and subsequent applications the materials produced by strong methane-chemical reaction (MCR) in alcohol solution showed concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segnetomagnetics, containing a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds were synthesized having thickness up to 10～50 nm and showing magnetic, electrical and other properties. It was confirmed in magnetizing process that powders of quartz and lava-scoria produced by MCR were better oil adsorbent as of oleophilic and floating matter on water surface although their specific gravities are comparably more than 1 in quartz or less than unity, as that of water, in lava-scoira. Therefore, it will be Possible and very useful to remove low density and light gravity oil spillage in difficult recovery from sea and inland water contamination spread on water surface, by marine accident and ship sinking accident occurring frequently in recent years, by way of magnetic adsorbent conveyer system in continuous, if it could be built up the mass Production system of water-floating magnetizable oleophilic adsorbent materials with use of iow cost and good Qualify lava-scoria spread on volcano district in Je-ju island. And, there will also be urgent advent of necessity with strong possibility to develop useful applications of various magnetic functional materials include oleophilic adsorbent for removal of sea oil-contaminants and maritime pollutants, and other kinds of various utilities in industrial applications and practical uses of novel functional materials in the fields of environments and health care applications with in deep expectation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.186-195
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• 2018

A field study was conducted over a 3-year period from 2014 to 2016 in the central plain area, Suwon, Korea, 1) to compare the biomass production between machine-transplanted and water-broadcast seeded silage rice and 2) to elucidate the growth factors that affect the difference in biomass production between the two cultivation practices. The heading date for the water-broadcast seeded silage rice was September 11-18, which was delayed by 11-17 days when compared to that for the machine-transplanted silage rice. On average, water-broadcast seeded silage rice had a shorter plant height, more panicles per area, and a greater biomass production because of the increased straw dry weight. However, the difference in dry weight of each plant organ between the two cultivation practices exhibited yearly variation. When the data were pooled across experimental years, cultivation practices, and varieties, biomass production was highly positively correlated with straw dry weight but not with panicle dry weight. When the ratio of water-broadcast seeding to machine-transplanting was analyzed, total dry weight and straw dry weight were positively associated with each other, whereas no relationship was found between total dry weight and panicle dry weight. Despite that water-broadcast seeded silage rice produced more panicles per area than machine-transplanted silage rice, the two cultivation practices had a similar dry weight per culm. Therefore, we conclude that the silage rice from the water-broadcast seeding, compared to the machine-transplanting, produced more biomass because of the combination of the increased panicle number per area and a similar dry weight per culm. These results suggest that silage rice could be produced through water-broadcast seeding to increase biomass production with low labor and cost input.

• Korean Journal of Poultry Science
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• v.18 no.1
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• pp.43-55
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• 1991

This experiment was conducted to study the sparing effects of animal proteins on weight gain, nutrients utilizability and economic analysis of broiler. Experiment diet contained different ratio of animal and plant protein and were supplemented different levels of methionine and lysine for the respective protein levels. A total of 264 broiler chicks were fed four diets of control, $T_1$, $T_2$ and $T_3$ for 42 days from April 7, 1990 to May 19, 1990. Dietary protein levels of control, $T_1$, $T_2$ and $T_3$ for starter and finisher were 20~18, 18~16, 18~16 and 22~20%, respectively. Methionine and lysine levels of control, $T_1$, $T_2$ and $T_3$ were 0.4~1.1, 0.44~1.21, 0.48~1.32 and 0.48~1.32% for starter diet, respectively, and were 0.32~0.90. 0.35~0.99, 0.38~1.08 and 0.38~1.08% for finisher diet, respectively. The results obtained were summarized as follows. 1. The birds fed control diet gained most for overall period. $T_3$ treatment which was high in protein, methionine and lysine levels gained most for finisher period. 2 The birds fed control diet consumed most feed, and the birds fed T$_3$ diet consumed least feed. for overall period. Feed conversion during 1~4 weeks was better in $T_1$ (1.51) and $T_2$ (1.53) than in control (1.61) and $T_3$ (1.63) . During 4~6weeks, feed conversion was better in $T_3$ (1.37) and control(1.58) than T, (2.05) and T, (2.16) (P＜0.01) 3. Dry matter, crude fiber and NFE utilizability were increased for 1~4 weeks and decreased for 4~6 weeks as methionine and lysine levels increased and crude protein utilizability tended to be increased as protein levels increased. 4. Abdominal fat content was lowest in bird fed control diet and was high in birds fed low protein diet Carcass percentage was highest at control and the abdominal fat content was higher in bird fed lower protein diet than bird fed other protein diets(P＜0.05). 5. Feed cost per kg weight gain was lowest at $T_3$ which contained more soybean oil meal than other feeds and next was control. According to the results of this experiment, it was revealed that optimum protein, methionine and lysine levels for starter and finisher broiler diet were 20~18, 0.4~0.32 and 1.1~0.9%, respectively.

• Korean Journal of Poultry Science
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• v.18 no.1
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• pp.9-31
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• 1991

The purpose of this study was to investigate the effects of dietary methionine and lysine levels on laying hen performance. The level of protein was fixed 15% during whole experiment period, but the levels of methionine and lysine were 0.30% and 0.58% (Low), 0.32% and 0.64% (Medium), 0.35% and 0 70% (High), respectively. Total 288 laying pullets of 22 weeks age were reared from January 28, 1989 to March 23, 1990 for 60weeks. The results obtained were summarized as follows : 1. The e99 Productions were highest in medium treatment in phase I (22~42weeks of age), phase II (42~62 weeks of age) and phase III (62~82weeks of age) and especially, there was significant difference among treatments during phase II (P＜0.05). 2. Egg weight was significantly increased as the levels of methionine and lysine were increased up to methionine and lysine were 0.32% and 0.64%, respectively(P＜0.01). 3. Daily egg mass was highest when the levels of methionine and lysine were 0.32% and 0.64%, respectively and there were significant differences among treatments during phase I and phase II (P＜0.01) 4. Daily feed intake was increased as the levels of methionine and lysine were increased, and there was significant difference among treatments during phase III (P＜0.05). 5. Feed efficiency was best in medium treatment in phase I and phase II (P＜0.01) 6, Viability was highest in medium treatment, but there was no significant difference among treatments. 7. Nutrient utilizability of experimental diets was not significantly different among treatments. 8. Eviscerated yield was highest and abdominal fat accumulation was lowest in medium treatment, but there was no significant difference among treatments. 9. Egg shell quality and chemical composition of egg content were not different among treatments. 10. The feed cost per kg egg mass was lowest in medium treatment and there were significant differences among treatments in phase I, phase II and whole egg laying period(P＜0.05)