• Journal of Korean Society of Forest Science
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• v.6 no.1
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• pp.27-31
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• 1967

The bamboo is a plant whose culm grows straight up. This growing characteristics has been widely utilized in industry and craft. But the developments of handcraft making and horticultural techniques in recent years become to demand the bent bamboo culms. This study has been conducted at the experimental grove located at Hyunnae Ri, Okkye Myun, Myungju Gun, Kangwon Do since 1960. Although it has been known that the secret for which bamboo shoots complet growth within 40 odd days lies in their rhizomes, this writer felt the bamboo culm sheath might be another factor in addition. Hence some were stripped of sheath in this bending study as the following: 1. Time of sheath stripping. 2. Direction of sheath stripped for arbitrary bending. 3. Accuracy of bending following the size (growth) of bamboo shoots. The following results were obtained: 1. Bamboo shoots begin to appear in April. But the bamboo shot up in June showed the best bending result with 68% of bending efficiency. 2. Bending of the culm was facilitated by stripping off the sheath located on the side of the direction toward which bending was desired. By doing this, the culm could be bent as much as 90 degrees. But the culm totally stripped of sheath could be bent in any direction. 3. In order to determine the accuracy of bending of bamboo shoots growing, sheath were stripped off the shoots of which height ranged from 10 centimeter to 150 centimeters. The shoots with height of 110 centimeters showed the best result with 90%.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.64-73
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• 2001

Generally potassium in the soil can be remained as water soluble, exchangeable, and available types, respectively. Theses types of potassiums are also known to keep their kinetic relationships to each other. The Purpose on this research was to investigate types and relationships of potassium in the soil, and the characteristics of potassium supply in different forest soils. The results could be summarized as follows; 1. The amounts of available potassium in A and B horizon soils by continuous leaching with 0.01N-HCl were as follows : for A Horizon soils, pohang(Gray brown forest soils), Changsung (Brown forest soils), and Youngwol(Dark red forest soils) were ranged from 0.2me/l00g to 0.8me/100g, Taean(Red and Yellow forest soils) was 0.1-0.6me/100g, Kapyung(Brown forest soils) was 0.2-0.4me/100g. For the B layer, Youngwol was 0.1-0.5me/100g, Pohang, Taean, Kapyung were 0.1-0.4me/100g, Changsung was 0.1-0.3me/100g, respectivly. 2. Of ten times-pulse leaching with 0.01N-HCl for A layer soil, more 80% of total available potassium leaching were recovered by the second pulse as leachate for Pohang, Changsung, Youngwol, while similar amounts of potassium in the leachate were obtained with the third pulse leaching for Kapyung, Taean, respectively, On the other hand, the 80 % release of available potassium from the B layer soil was obtained by the second pulse leaching for all areas investigated. 3. For the relationships between soluble potassium and exchangeable potassium, the exchangeable potassium was increased while the soluble potassium was not changed significantly in B layer. And both soluble potassium and exchangeable potassium in A layer were similar. For the relationship between exchangeable potassium and available potassium in both A and B layers, the amounts of available potassium increased by 1.2 to 1.5 times as the exchangeable potassium increased. 4. For distribution of all types of potassium throughout locations investigated, the types of potassium were in the decreasing orders of available, exchangeable, and soluble. 5. The simplified method for an analysis of all types of potassium by sequential leaching with 0.01N-HCl should be developed not only with respect to time-saving and efficiency but also verification of the relationship between available potassium and tree growth.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.213-219
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• 2009

This study was carried out to establish breeding system for interspecific hybridization of Lilium using spontaneous meiotic polyploidization of $F_1$ OA hybrid and its progenies. Pollen viability and germination of $F_1$ OA interspecific hybrid showed variation by collection time, indicating that pollen grain in June, which was natural blooming season, had better viability and germination ability than in October. 2n-gametes from spontaneous meiotic polyploidization of OA hybrid were crossed with either diploid Asiatic or Oriental hybrid, and subsequent progenies crossed with Asiatic hybrid as female and OA hybrid as male showed the highest efficiency, where 2x-2x A$\times$OA produced 0.64 plants per cross combination, while 2x-2x, O$\times$OA and 2x-2x, OA$\times$A crosses produced 0.42 and 0.4 plant per ovary, and especially no progeny was obtained in 2x-2x, OA$\times$O cross combination. For the subsequent progeny production, a cross between diploid Asiatic hybrid as female and diploid OA hybrid as male was the best ploidy combination. Ploidy level of subsequent progeny derived from backcross with 2n-gametes of OA hybrid revealed that triploids from 2x-2x OA$\times$A, tetraploids from both 4x-2x, AA$\times$OA and OO$\times$OA, diploid from 2x-2x, O$\times$OA, and diploids or triploids from 2x-2x, A$\times$OA crosses were produced respectively.

• Journal of Legislation Research
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• no.44
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• pp.757-799
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• 2013

Ever since Korea and Vietnam reestablished diplomatic relations, the two countries'bond has become stronger than ever, augmenting the range of exchange between them in almost every possible field including politics, economy, society, and culture at such a high speed. Among many, an increase in number of Vietnamese immigrant women in international marriage is worthy of close attention. Since 2010, Vietnamese has topped the proportion of total foreign women married to Korean men, having surpassed Chinese. Nonetheless, the quick international marriage between Korean men and Vietnamese women, which usually happens without sufficient time to get to know about different cultures and languages, has not only raised problems for people concerned, but numerous social issues as well. Recognizing these problems, a number of government departments have provided various support on policies and legal issues toprotect multicultural families as a means of social integration and settlement support. Nevertheless, the support policies until now have been generalizing all of the immigrant women in international marriage as people subject to protection. Thus, considering every immigrant women as people in need, and trying to help them with various social issues have caused the government a high cost and low efficiency. This thesis emphasizes the point that through the cases of Vietnamese immigrant women in international marriage, there should be a specific support plan for specific people in need, reflecting various traits of different cultures and societies, in order to ease their settlement in Korea. Moreover, it suggests detailed plans for improvements on legal and institutional problems. Although the Vietnamese government forbids commercial agents for international marriage, many of agencies are still active and to help the immigrant women, who desire to return and resettle in Vietnam in case of divorce, this thesis suggests legal and institutional remedies for Korean and Vietnamese government. The composition of the thesis follows below: Part II on social and cultural traits of international marriage between Korean men and Vietnamese women. Part III on institutional problems and plans for improvements regarding settlement of immigrant women in international marriage. Part IV on legal and institutional problems and plans for improvements regarding divorced immigrant women and their return to Vietnam. Part V on conclusion. Divorce is not a flaw anymore nowadays, but in case of Vietnamese immigrant women ininternational marriage, an inadequate legal system hampers their resettlement process. Cases of not being ableto remove their own names from the family register due to poor financial and legal abilities are often identified and it is both the Vietnamese and Korean governments'duty to acquit their ethical responsibilities by seeking ways to institutionally and financially support them.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.970-976
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• 2011

Strip tiller equipment was developed to reduce soil erosion in the slope land for highland agricultural area. The equipment consisted of 4 rows strip tillage device and fertilizer applicator. The field was tilled in 10 cm width and in 10 cm depth by the equipment, of which tilled surface was 16.7% of full-width tillage. The working time and fuel consumption of the equipment were $3.8hours\;ha^{-1}$ and $24.4L\;ha^{-1}$ respectively, which were 59% and 74% less than those of the conventional tillage. Fertilizer efficiency of the equipment in cultivation of Chinese cabbage was 1.7, 1.6 and 1.5 times higher in nitrate, phosphorous and potassium respectively, than conventional tillage. When the equipment was used after covering of rye residue, the quantity of runoff was 49~67% lower than the conventional tillage. And the quantity of soil loss were 1.3 and $0.2Mg\;ha^{-1}$ at right after and 30 days after planting of Chinese cabbage respectively, while 11.5 and $4.1Mg\;ha^{-1}$ in conventional tillage. In conclusion, the strip tillage equipment developed in this study can be applicable to slope land, so that soil loss of 90% can be reduced.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.60-77
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• 2021

From 2007 to 2011, four Goryeo Dynasty vessels, namely the Taean treasure ship, Taean Mado Shipwreck No.1, No.2, No.3 were discovered in Taean area, Chungcheongnam-do province. From the shipwrecks, 175 pieces of mokkan (wooden tablet) were excavated. These mokkans are the only case of Goryeo Dynasty and represent the unique usage of mokkan as cargo tags, after the paper replaced the wooden tablets as writing materials. The Taean mokkans provide details, such as the year, recipient, port of origin, types of the cargo, quantity and unit, the name of the responsible person for shipment. Thus, they enable us to speculate about the characteristics of the cargo. Furthermore, through studying the writing style, form, material and manufacturing method, researchers can extract which form and characteristics were favored at that time. The Taean mokkans have no preset style for writing. Therefore, they can be written selectively and freely. And since the mokkan were attached to cargos, mokkans with furrows on upper side were favored, and efficiency and simplification of the manufacturing process were priorities in making mokkans. The Taean mokkans can be compared to those from the Shinan ship and the Quanzhou ship because those are of the same era and use. On the writing styles and information, Chinese mokkans are focused on the cargo owners, while The Taean mokkan includes more detailed information, such as the recipients. In forms, Chinese mokkans have maximum thickness of 1.0 centimeter and have pointed edges in lower parts, while mokkans from Taean do not have fixed thickness or edges. Furthermore, Chinese mokkans and Korean mokkans have different styles from manufacturing methods and material selections. These differences between Chinese and Goryeo mokkan are related to the differences between littoral-transport Goryeo ships and ocean-transport Chinese ships, such as shipping distances, types of cargo, shipping systems, packing methods, and transport operators. At the moment, because there are only small amount of data and materials of Chinese mokkan, comparative studies regarding Goryeo and Chinese mokkan can only be fragmentary. However, this article can be a base from which to expand the scope of Goryeo mokkan studies.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.5
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• pp.1-14
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• 2021

Innovation and Scale-up of Start-up companies are becoming important national tasks. In the past, it was spread the start-up policy paradigm such as 'Start-up America', 'Start-up Chile', 'Start-up Britain' to overcome the recession globally. However as the economic recovery has become more visible recently in advanced economies, it is shifting from a start-up support policy to a scale-up oriented policy paradigm such as 'Scale-up America', Scale-up UK', 'Scale-up Denmark'. It is necessary to enter the scale-up phase beyond the start-up phase to increase the number of high-quality jobs and to continue economic growth. Therefore, it is necessary to grow the start-up into a strong medium-sized company and to lay the foundation for survival. Therefore, the purpose of this study is to consider the antecedent factors that influence the scale-up aspiration for the start-up firm to grow into a scale-up company, and empirically identifies the differences between the stages of economic development and entrepreneurs in the country. In order to accomplish the purpose, this study predicted scale-up by aspiration which is a predictor of scale-up behavior because it is difficult to achieve visible growth in a short period of time due to the characteristics of start-up companies. In order to empirically explore these relationships, the data were collected from nascent entrepreneurs who have less than 3.5 years of the Adult Population Survey(APS) among the subjects surveyed by the Global Entrepreneurship Monitor(GEM) and the national economic development stage are divided into Innovation-driven, Efficiency-driven, Factor-driven type economies. For the test hypotheses, this study adopted the multi-level model analysis for comparison between national economic development stages and using the R 3.5.0 program. The results of this study are as follows. There is difference between the national economic development and the entrepreneur in the relationship between innovation orientation of entrepreneurs and scale-up aspirations. As the economy of the country develops, the innovation activity of the entrepreneur becomes more active. Since start-ups are heavily influenced by entrepreneurs, there is a difference in the degree of aspiration depending on how innovative an entrepreneur is in the same environment. In terms of the relationship between innovation orientation and scale-up aspiration, the fear of failure was found to differ between national economic development and entrepreneurs. The fear of failure differ from country to country, and this is one of the important factors affecting entrepreneurial activities. It is expected that the factors influencing the growth of the start-up companies which are identified through the results of these studies, will be used to create a suitable scale-up ecosystem according to the national economic development stage.

• Korean Journal of Remote Sensing
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• v.37 no.6_3
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• pp.1985-1999
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• 2021

The purpose of this study is to apply urban heat island reduction techniques(green roof, cool roof, and cool pavements using heat insulation paint or blocks) recommended by the Environmental Protection Agency (EPA) to our study area and determine their actual effects through a comparative analysis between land cover objects. To this end, the area of Mugye-ri, Jangyu-myeon, Gimhae, Gyeongsangnam-do was selected as a study area, and measurements were taken using a drone DJI Matrice 300 RTK, which was equipped with a thermal infrared sensor FLIR Vue Pro R and a visible spectrum sensor H20T 1/2.3" CMOS, 12 MP. A total of nine heat maps, land cover objects (711) as a control group, and heat island reduction technique-applied land covering objects (180) were extracted every 1 hour and 30 minutes from 7:15 am to 7:15 pm on July 27. After calculating the effect values for each of the 180 objects extracted, the effects of each technique were integrated. Through the analysis based on daytime hours, the effect of reducing heat islands was found to be 4.71℃ for cool roof; 3.40℃ for green roof; and 0.43℃ and -0.85℃ for cool pavements using heat insulation paint and blocks, respectively. Comparing the effect by time period, it was found that the heat island reduction effect of the techniques was highest at 13:00, which is near the culmination hour, on the imaging date. Between 13:00 and 14:30, the efficiency of temperature reduction changed, with -8.19℃ for cool roof, -5.56℃ for green roof, and -1.78℃ and -1.57℃ for cool pavements using heat insulation paint and blocks, respectively. This study was a case study that verified the effects of urban heat island reduction techniques through the use of high-resolution images taken with drones. In the future, it is considered that it will be possible to present case studies that directly utilize micro-satellites with high-precision spatial resolution.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.268-276
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• 2018

BACKGROUND: In the month of January 2018, fine dust alerts and warnings were issued 36 times for $PM_{10}$ and 81 times for PM2.5. Air quality is becoming a serious issue nation-wide. Although interest in air-purifying plants is growing due to the controversy over the risk of chemical substances of regular air-purifying solutions, industrial spread of the plants has been limited due to their efficiency in air-conditioning perspective. METHODS AND RESULTS: This study aims to propose a vegetation-based bio-filter system that can assure total indoor air volume for the efficient application of air-purifying plants. In order to evaluate the quantitative performance of the system, time-series analysis was conducted on air-conditioning performance, indoor air quality, and comfort index improvement effects in a lecture room-style laboratory with 16 persons present in the room. The system provided 4.24 ACH ventilation rate and reduced indoor temperature by $1.6^{\circ}C$ and black bulb temperature by $1.0^{\circ}C$. Relative humidity increased by 24.4% and deteriorated comfort index. However, this seemed to be offset by turbulent flow created from the operation of air blowers. While $PM_{10}$ was reduced by 39.5% to $22.11{\mu}g/m^3$, $CO_2$ increased up to 1,329ppm. It is interpreted that released $CO_2$ could not be processed because light compensation point was not reached. As for the indoor comfort index, PMV was reduced by 83.6 % and PPD was reduced by 47.0% on average, indicating that indoor space in a comfort range could be created by operating vegetation-based bio-filters. CONCLUSION: The study confirmed that the vegetation-based bio-filter system is effective in lowering indoor temperature and $PM_{10}$ and has positive effects on creating comfortable indoor space in terms of PMV and PPD.

• Journal of the Korean GEO-environmental Society
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• v.20 no.2
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• pp.41-48
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• 2019

Soil compaction is one of the most important activities in the area of civil works, including road construction, airport construction, port construction and backfilling construction of structures. Soil compaction, particularly in road construction, can be categorized into subgrade compaction and roadbed compaction, and is significant work that when done poorly can serve as a factor causing poor construction due to a lack of compaction. Currently, there are many different types of compaction tests, and the plate bearing test and the unit weight of soil test based on the sand cone method are commonly used to measure the degree of compaction, but many other methods are under development as it is difficult to secure economic efficiency. For the purpose of this research, a portable penetration meter called the Free-Fall Penetration Test (FFPT) was developed and manufactured. In this study, a homogeneous sample was obtained from the construction site and soil was classified through a sieve analysis test in order to perform grain size analysis and a specific gravity test for an indoor test. The principle of FFPT is that the penetration needle installed at the tip of an object put into free fall using gravity is used to measure the depth of penetration into the road surface after subgrade or roadbed compaction has been completed; the degree of compaction is obtained through the unit weight of soil test according to the sand cone method and the relationship between the degree of compaction and the depth of the penetration needle is verified. The maximum allowable grain size of soil is 2.36 mm. For $A_1$ compaction, a trend line was developed using the result of the test performed from a drop height of 10 cm, and coefficient of determination of the trend line was $R^2=0.8677$, while for $D_2$ compaction, coefficient of determination of the trend line was $R^2=0.9815$ when testing at a drop height of 20 cm. Free fall test was carried out with the drop height adjusted from 10 cm to 50 cm at increments of 10 cm. This study intends to compare and analyze the correlation between the degree of compaction obtained from the unit weight of soil test based on the sand cone method and the depth of penetration of the penetration needle obtained from the FFPT meter. As such, it is expected that a portable penetration tester will make it easy to test the degree of compaction at many construction sites, and will lead to a reduction in time, equipment, and manpower which are the disadvantages of the current degree of compaction test, ultimately contributing to accurate and simple measurements of the degree of compaction as well as greater economic feasibility.