• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.390-399
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• 2020

We investigated the effect of seedling age and planting density on early growth performance of Zelkova serrata trees. Containerized Z. serrata seedlings, 1-year-old and 2-year-old, were planted according to two different planting densities (3,000 and 5,000 trees ha-1) at the end of March, 2017. Three plots were established for each treatment (2 seedling ages × 2 planting densities). We calculated the survival rate (%) of out-planted seedlings as well as the stem volume based on the root collar diameter (RCD) and height (H) in September of each year, from 2017 to 2019. Seedling age and planting density did not affect survival rate of the out-planted trees. Planting density did not affect height of the trees, whereas the treatment significantly affected RCD and the H/D ratio for 2-year-old seedlings in 2019. The stem volume per tree was highest in the plot of 2-year-old seedlings at 5,000 trees ha-1 and lowest in the 1-year-old seedlings at 3,000 trees ha-1. In addition, the tree height in both 1-year-old and 2-year-old Z. serrata trees was greater in the 5,000 trees ha-1 plot than in the 3,000 trees ha-1 plot. There was no interactive effect between seedling age and planting density on stem volume; however, as seedling age and planting density increased, stem volume of Z. serrata trees increased. The values for stem volume per hectare are 85%, 68%, and 300% higher in 1-year-old 5,000 trees ha-1, 2-year-old 3,000 trees ha-1, and 2-year-old 5,000 trees ha-1 plots, respectively, compared to the values in 1-year-old 3,000 trees ha-1. This result shows that high planting density (close planting) affects tree growth differently based on seedling age, and suggests that the planting density of 5,000 trees ha-1 is suitable for 2-year-old seedlings to improve early growth field performance.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.2-31
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• 2020

CheomSeongDae (瞻星臺) is a stone structure built in Gyeongju, the former Silla Dynasty capital, during the reign of Queen Seondeok (632~647AD). There exist dozens of hypotheses regarding its original purpose. Depending on to whom you ask, the answer could be a celestial observatory, a religious altar, a Buddhist stupa, a monumental tower symbolizing scientific knowledge, and so on. The most common perception of the structure among lay people is a stargazing tower. Historians, however, have suggested that it was intended as "a gateway to the heavens", specifically the Trāyastriṃśa or the second of the six heavens of Kāmadhātu located on the top of Mountain Sumeru. The name "Cheom-seong-dae" could be interpreted in many different ways. 'Cheom (瞻)' could refer to looking up, staring, or admiring, etc.; 'Seong (星)' could mean a star, heaven, night, etc.; and 'heaven' in that context can be a physical or religious reference. 'Dae (臺)' usually refers to a high platform on which people stand or things are placed. Researchers from the science fields often read 'cheom-seong' as 'looking at stars'; while historians read it as 'admiring the Trāyastriṃśa' or 'adoring Śakra'. Śakra is said to be the ruler of Trāyastriṃśa' who governs the Four Heavenly Kings in the Cāturmahārājika heaven, the first of the six heavens of Kāmadhātu. Śakra is the highest authority of the heavenly kings in direct contact with humankind. This paper examined the usages of 'cheom-seong' in Chinese literature dated prior to the publication of 『Samguk Yusa』, a late 13th century Korean Buddhist historical book that contains the oldest record of the structure among all extant historical texts. I found the oldest usage of cheom-seong (瞻星臺) in 『Ekottara Āgama』, a Buddhist script translated into Chinese in the late 4th century, and was surprised to learn that its meaning was 'looking up at the brightness left by Śakra'. I also found that 'cheom-seong' had been incorporated in various religious contexts, such as Hinduism, Confucianism, Buddhist, Christianism, and Taoism. In Buddhism, there was good, bad, and neutral cheom-seong. Good cheom-seong meant to look up to heaven in the practice of asceticism, reading the heavenly god's intentions, and achieving the mindfulness of Buddhism. Bad cheom-seong included all astrological fortunetelling activities performed outside the boundaries of Buddhism. Neutral cheom-seong is secular. It may help people to understand the nature of the physical world, but was considered to have little meaning unless relating to the spiritual world of Buddhism. Cheom-seong had been performed repetitively in the processes of constructing Buddhist temples in China. According to Buddhist scripts, Queen Māyā of Sakya, the birth mother of Gautama Buddha, died seven days after the birth of Buddha, and was reborn in the Trāyastriṃśa heaven. Buddha, before reaching nirvana, ascended from Jetavana to Trāyastriṃśa and spent three months together with his mother. Gautama Buddha then returned to the human world, stepping upon the stairs built by Viśvakarman, the deity of the creative power in Trāyastriṃśa. In later years, King Asoka built a stupa at the site where Buddha descended. Since then, people have believed that the stairway to the heavens appears at a Buddhist stupa. Carefully examining the paragraphic structure of 『Samguk Yusa』's records on Cheomseongdae, plus other historical records, the fact that the alignment between the tomb of Queen Seondeok and Cheomseongdae perfectly matches the sunrise direction at the winter solstice supports this paper's position that Chemseongdae, built in the early years of Queen SeonDeok's reign (632~647AD), was a gateway to the Trāyastriṃśa heaven, just like the stupa at the Daci Temple (慈恩寺) in China built in 654. The meaning of 'Cheom-seong-dae' thus turns out to be 'adoring Trāyastriṃśa stupa', not 'stargazing platform'.

• Journal of Korea Port Economic Association
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• v.24 no.4
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• pp.363-384
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• 2008

This study aims at improving Korea's competitiveness in port logistics through marketing strategy with integrating the conceptual approach into the empirical one and combining both the oldest military treatise and the newest evaluating model in social science that was applied by the HFP(hierarchical fuzzy process) model enhanced by the KJ method. The empirical results of this study show Busan in the middle among subject ports. At present, Korea plays a reciprocal role in the port market in East Asia, but in the medium- and long-term, Korea's ports will vie together with most major ports in the East Asian region. A descriptive investigation shows that Korea's developing tasks in port logistics must be considered in the context of the direction for developing port policies, the necessity of expanding port facilities in the capital region, securing the sufficient traffic volume through the establishment of the hinterland linking system and its positive utilization, and reforming the direction for developing the global logistics through increased port competitiveness. In the short- and medium-term, Korea must use the opportunity factor of 'Growth and open door policy of China' as a geoeconomic advantage and to utilize Korea's ports as a gate to Chinese foreign trade. With the rise of China's economy, China also plays a significant role in both port and airport markets. Hence, the linking system between the two must be established to meet the expanding traffic volume, especially in the capital area. Moreover, it is necessary for Korea to secure port logistics through the establishment of the hinterland linking system and its positive utilization. The great accomplishment of this paper is to present strategies to increase Korea's port competitiveness in the rapidly changing environments of world logistics with the focus on both the oldest military strategic treatise and the newest empirical method in social science. In order to reinforce this study, it needs further compensative research because the evaluation structure could be subdivided with more extensive and precise criteria.

• Journal of Technology Innovation
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• v.26 no.3
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• pp.37-68
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• 2018

Since the 20th century, automobiles, which are the most common means of transportation, have been evolving as the use of electronic control devices and automotive semiconductors increases dramatically. Automotive semiconductors are a key component in automotive electronic control devices and are used to provide stability, efficiency of fuel use, and stability of operation to consumers. For example, automotive semiconductors include engines control, technologies for managing electric motors, transmission control units, hybrid vehicle control, start/stop systems, electronic motor control, automotive radar and LIDAR, smart head lamps, head-up displays, lane keeping systems. As such, semiconductors are being applied to almost all electronic control devices that make up an automobile, and they are creating more effects than simply combining mechanical devices. Since automotive semiconductors have a high data rate basically, a microprocessor unit is being used instead of a micro control unit. For example, semiconductors based on ARM processors are being used in telematics, audio/video multi-medias and navigation. Automotive semiconductors require characteristics such as high reliability, durability and long-term supply, considering the period of use of the automobile for more than 10 years. The reliability of automotive semiconductors is directly linked to the safety of automobiles. The semiconductor industry uses JEDEC and AEC standards to evaluate the reliability of automotive semiconductors. In addition, the life expectancy of the product is estimated at the early stage of development and at the early stage of mass production by using the reliability test method and results that are presented as standard in the automobile industry. However, there are limitations in predicting the failure rate caused by various parameters such as customer's various conditions of use and usage time. To overcome these limitations, much research has been done in academia and industry. Among them, researches using data mining techniques have been carried out in many semiconductor fields, but application and research on automotive semiconductors have not yet been studied. In this regard, this study investigates the relationship between data generated during semiconductor assembly and package test process by using data mining technique, and uses data mining technique suitable for predicting potential failure rate using customer bad data.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.97-106
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• 2016

This study is to suggest the necessity of landscaping alternatives for succession of Takjok(濯足) culture by considering the background and meaning of Takjok's cultural phenomenon shown in old literatures, paintings and ruins of landscape architecture as a front morphemes. Its result is as follows. 1. An old idiom, 'Takyung Takjok(濯纓濯足)' implying a disinterested living attitude from the mundane world and an attitude complying with the nature, has been sublimated to 'Takjokjiyu(濯足之遊)' which means living in comfortable retirement through life in seclusion(隱逸). 2. The meaning of Takjok did not expand into, not only Takyung Takjok, but also into Takcheong(濯淸), Tako(濯吾), and Taksa(濯斯) with continued expansion in its meaning. The spaces the meaning of Takyung Takjok is implied on have also newly expanded into the artificial spaces, including Jeong(亭-pavilion) Jae(齋-house) Heon(軒-eaves), and Ji(池-pond), as well as the natural spaces, including Am(巖-rock) Dae(臺-flat foundation) Dam(潭-deep pond) Ban(盤-dish rock) Seok(石-stone) So(沼-shallow pond) San(山-mountain) Bong(峰-peak), and Cheon(泉-water hole). 3. As seen here, the cultural phenomenon of Takyung Takjok, which have derived from the Dangho(堂號) of buildings, the names of natural objects in Palgyung and Gugok(eight sceneries and nine curves), facilities of Byeolseo garden and Seowon, and the Amgakseo in nature, is worth noting. 4. It should be considered that Takjok includes ordinary people's wisdom to resist the hot weather as well as classical scholar's ideal and the veneration of antiquity. From this perspective, water space, Takjok rocks, and use of water based on the environmental supportability should be newly focused as a recreational space and it reminds us that the spirit of Takjok is a classical mental healing method.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.2
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• pp.132-140
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• 2005

This study was conducted to develop regional site index equations for main tree species in Gangwon, Gyunggi-Chungcheong, Gyungsang, and Jeolla area of Korea, using environmental and soil factors obtained from a digital forest site map. Using the large data set obtained from the digital forest map, a total of 28 environmental and soil factors were regressed on site index by tree species for developing the best site index equations for each of the regions. The selected main tree species were Larix 1eptolepis, Pinus koraiensis, Pinus densiflora, Pinus thunbergii, and Quercus acutissima. Finally, four to five environmental and soil factors by species were chosen as independent variables in defining the best regional site index equations with the highest coefficients of determination $(R^2)$. For those site index equations, three evaluation statistics such as mean difference, standard deviation of difference and standard error of difference were applied to the data sets independently collected from fields within the region. According to the evaluation statistics, it was found that the regional site index equations by species developed in this study conformed well to the independent data set, having relatively low bias and variation. It was concluded that the regional site index equations by species had sufficient capability for the estimation of site productivity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.177-183
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• 1989

Lower leaves of aromatic tobacco are also much lower in Quality than upper leaves. So feasibility test of no harvesting and curing of lower leaves was conducted under high planting density and high nitrogen conditions with conventional cultural system. Effect of harvesting time on yield and Quality were investigated under 2 nitrogen levels. Among harvesting methods of conventional harvest with priming under high planting density, no-harvest of first priming, removal of lower leaves which relevant to first prime stalk before maturity, no-harvest of first and second priming. no-harvesting or pruning of first prime stalk before maturity was best in yield, price and in crude income. The shortor the harvest period became, the lower the yield, price and contents of reducing sugar and nicotine became, but reverse in this trends with total nitrogen and protein nitrogen. So 6 or 8 days interval of harvest is most recommendable.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.6
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• pp.155-166
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• 2018

The purpose of this study is to analyze the impact of self-efficacy of SMEs' organization members on job engagement and job performance, and to analyze the difference between gender and marital status by applying SEM-ANN analysis. To accomplish the study purpose, 285 valid samples were collected from 400 SMEs' organization members and analyzed. In this study, self - efficacy consisted of three sub-dimensions: self-confidence, self-regulation efficacy, and task difficulty preference. As a result of the analysis, self - efficacy such as self-confidence, self-regulation efficacy, and task difficulty preference had a positive direct effect on job engagement. In addition, self-efficacy and self-control efficacy have a positive effect on job performance, but the preference of task difficulty has no significant effect. In addition, job engagement has a positive(+) effect on job performance, and has a mediating role in the relationship between self-efficacy and job performance. Also, married males preferred self-regulation efficacy, while females preferred self-regulation and self-control efficacy regardless of marital status. The purpose of this study is to present the framework of self-efficacy-job engagement-job performance of SMEs by measuring the self-efficacy related researches mainly in education and service industries, and is meaningful that companies can help to find the basis of management of organization members by gender and marital status of organization members. In addition, the SEM-ANN analysis process of this study is different in that it explains the nonlinear (nonobservative) relationship that can analyze the influence or the combination of the reference variables in the linear (compensatory) relation using the SEM.

• Journal of Ginseng Culture
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• v.5
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• pp.32-51
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• 2023

Because red ginseng was exported in large quantities to the Qing Dynasty in the 19th century, a large-scale ginseng cultivation complex was established in Kaesong. Sibyunje (時邊制), a privately led loan system unique to merchants in Kaesong, made it possible for them to raise the enormous capital required for ginseng cultivation. The imperial family of the Korean Empire promulgated the Posamgyuchik (包蔘規則) in 1895, and this signaled the start of the red ginseng monopoly system. In 1899, when the invasion of ginseng farms by the Japanese became severe, the imperial soldiers were sent to guard the ginseng farms to prevent the theft of ginseng by the Japanese. Furthermore, the stateled compensation mission, Baesanggeum Seongyojedo (賠償金 先交制度), provided 50%-90% of the payment for raw ginseng, which was paid in advance of harvest. In 1895, rising seed prices prompted some merchants to import and sell poor quality seeds from China and Japan. The red ginseng trade order was therefore promulgated in 1920 to prohibit the import of foreign seeds without the government's permission. In 1906-1910, namely, the early period of Japanese colonial rule, ginseng cultivation was halted, and the volume of fresh ginseng stocked as a raw material for red ginseng in 1910 was only 2,771 geun (斤). However, it increased significantly to 10,000 geun between 1915 and 1919 and to 150,000 geun between 1920 and 1934. These increases in the production of fresh ginseng as a raw material for red ginseng were the result of various policies implemented in 1908 with the aim of fostering the ginseng industry, such as prior disclosure of the compensation price for fresh ginseng, loans for cultivation expenditure in new areas, and the payment of incentives to excellent cultivators. Nevertheless, the ultimate goal of Japanese imperialism at the time was not to foster the growth of Korean ginseng farming, but to finance the maintenance of its colonial management using profits from the red ginseng business.

• Journal of Korean Society of Forest Science
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• v.112 no.1
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• pp.71-82
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• 2023

Forest biomass is used as a representative indicator of forest size, maturity, and productivity. Therefore, quantitative evaluation is important for management and harvest as well as the evaluation of ecosystem functions and services including CO₂ absorption. The allometric equation is a widely used method for estimating the value of each component through the relative growth rate of plants. Recently, studies indicated that the relative growth of trees is changing because of the increased CO₂ concentration in the atmosphere and the resulting climate change, raising the need to review the previously developed relative growth models and coefficients. In this study, the height-diameter at breast height (DBH) relationships of four major tree species in Korea [(Pinus densiflora (PD), Larix kaempferi (LK), Quercus variabilis (QV), and Quercus mongolica (QM)] were analyzed using the 5th-7th National Forest Inventory (NFI) data. Furthermore, these results were compared with the present yield table from the National Institute for Forest Science. This analysis revealed that the expected height for the same DBH increased as the NFI progressed. For example, in model analysis, the expected heights for PD, LK, QV, and QM for DBH of 25 cm were 12.48, 19.17, 14.47, and 13.19 m, respectively, in the 5th NFI data. In the 7th NFI data, these values were estimated as 13.61 (+9.1%), 21.58 (+12.7%), 15.76 (+8.9%), and 13.93 m (+5.6%), respectively. These results indicate that the major tree species in South Korean forests currently are more vigorous in height growth than in diameter growth when compared to the height-DBH development trends by tree species identified through past survey data.