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A Study on the Perception of Research Data Managers to Establish a Korea Research Data Commons System (국가연구데이터커먼즈 체계 수립을 위한 연구데이터 관리자들의 인식에 관한 연구)

  • Seong-Eun Park;Mikyoung Lee;Minhee Cho;Sa-Kwang Song;Dasol Kim;Hyung-Jun Yim
    • Journal of the Korean Society for information Management
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    • v.41 no.1
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    • pp.465-486
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    • 2024
  • The purpose of this study is to identify the current status of infrastructure and services for analyzing research data for research data managers at government-funded research institutions under the National Research Council for Science and Technology (NST) who will actually use the Korea Research Data Commons (KRDC), which is being developed by the Korea Institute of Science and Technology Information (KISTI) and to investigate the perceptions of research data managers related to the establishment of KRDC system. For the study, we conducted a survey targeting 24 government-funded research institutes, excluding KISTI, and interviewed research data managers from 9 of the 15 institutions surveyed who agreed to follow-up interviews. As a result of the survey, most institutions were providing related services, and their willingness to introduce an integrated analysis framework for the use of research data and provide a system for using externally released analysis software was also high. Meanwhile, when we investigated the external disclosure status of each institution's analysis services through follow-up interviews, only a minimal number of institutions were disclosing them to the outside world. The findings reveal that there is a demand to utilize analysis infrastructure and services when provided through the framework. However, it is difficult to disclose and share the analysis resources held by each organization. In order to establish the KRDC system, it is essential to share research sites' analysis infrastructure and services, and in addition, changes in the perception of research sites and institutional changes are necessary. Furthermore, there is a need to establish policies that consider the system's convenience, security, and compensation system raised in the follow-up interviews.

Prediction of Amyloid β-Positivity with both MRI Parameters and Cognitive Function Using Machine Learning (뇌 MRI와 인지기능평가를 이용한 아밀로이드 베타 양성 예측 연구)

  • Hye Jin Park;Ji Young Lee;Jin-Ju Yang;Hee-Jin Kim;Young Seo Kim;Ji Young Kim;Yun Young Choi
    • Journal of the Korean Society of Radiology
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    • v.84 no.3
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    • pp.638-652
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    • 2023
  • Purpose To investigate the MRI markers for the prediction of amyloid β (Aβ)-positivity in mild cognitive impairment (MCI) and Alzheimer's disease (AD), and to evaluate the differences in MRI markers between Aβ-positive (Aβ [+]) and -negative groups using the machine learning (ML) method. Materials and Methods This study included 139 patients with MCI and AD who underwent amyloid PET-CT and brain MRI. Patients were divided into Aβ (+) (n = 84) and Aβ-negative (n = 55) groups. Visual analysis was performed with the Fazekas scale of white matter hyperintensity (WMH) and cerebral microbleeds (CMB) scores. The WMH volume and regional brain volume were quantitatively measured. The multivariable logistic regression and ML using support vector machine, and logistic regression were used to identify the best MRI predictors of Aβ-positivity. Results The Fazekas scale of WMH (p = 0.02) and CMB scores (p = 0.04) were higher in Aβ (+). The volumes of hippocampus, entorhinal cortex, and precuneus were smaller in Aβ (+) (p < 0.05). The third ventricle volume was larger in Aβ (+) (p = 0.002). The logistic regression of ML showed a good accuracy (81.1%) with mini-mental state examination (MMSE) and regional brain volumes. Conclusion The application of ML using the MMSE, third ventricle, and hippocampal volume is helpful in predicting Aβ-positivity with a good accuracy.

Monitoring Pesticide Residues in Commercial Dried Red Peppers and Pepper Powders (유통 건고추와 고춧가루의 잔류농약 안전성 조사)

  • Yoo-Li Han;Hyun-Ju Kim;Sang-Tae Kim;Nan-Joo Park;Yu-Na Song;Yu-Mi Choi;Hye-Yeoun Lee;Bo-Min Son;Youn-Ho Kim;Jeong-Hwa Seo;Jong-Sung Son;Myoung-Ki Park;Yong-Bae Park
    • Journal of Food Hygiene and Safety
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    • v.39 no.3
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    • pp.221-230
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    • 2024
  • Pesticide residues were monitored in dried red pepper and pepper powder samples purchased in Northern Gyeonggi-do and from domestic online markets. The QuEChERS method was used to prepare 88 samples. GC-MS/MS and LC-MS/MS were used to analyze 338 pesticide residues. In the study, pesticide residues were detected in 70 samples (79.5%), with residues exceeding the maximum residue limits (MRL) in 4 samples (4.5%). Pesticide levels exceeded the MRL in imported samples, with two samples of dried red pepper and two samples of pepper powder showing elevated levels. Among the 61 pesticides detected, tebuconazole, a fungicide was most frequently detected (52 times). Tricyclazole, which is used to control the main disease affecting rice, exceeding the MRL in 3 of 12 Vietnam-origin samples. Ethion exceeded the MRL in one Indian-origin sample. Both tricyclazole and ethion are banned for use in pepper products in Korea and are regulated under the positive list system (PLS). Conversely, pesticides detected in domestic samples were within the MRLs. Therefore, authorities should monitor pesticide residues in imported red pepper products.

Integrative CVP Framework Design, Using Lean-startup Methodology (린스타트업방법론을 이용한 통합 고객가치제안모델 설계)

  • Ahn, Eung-hee
    • Journal of Venture Innovation
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    • v.7 no.3
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    • pp.45-63
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    • 2024
  • The success of a company in the market is linked to the value it delivers to its customers. However, that value is not always constant. As the environment changes, so do customer experiences and requirements, and eventually the value they seek also evolves. Thus, a timely, clear, and effective value proposition, along with the associated benefits, becomes the functional, psychological, and economic foundation of a business. Therefore, the customer value proposition is crucial in terms of Product-Market Fit (PMF), establishing competitive differentiation, and delivering consistent messaging. Despite this, the most widely known and utilized model related to the Customer Value Proposition (CVP) in general businesses is the Value Proposition Canvas (VPC) by Osterwalder and Pigneur. Apart from that, there are only a few other models used by scholars and experts. In this paper, I selected the VPC model, which is widely used by business practitioners globally, and two other major CVP models well-known to experts. I conducted a detailed analysis of these models and derived the essential elements and key features of a customer value proposition. These were then combined with the Lean Startup methodology, which is frequently used for innovation today, to design an integrated CVP model that startups can easily utilize. The framework proposed in this study is a comprehensive CVP model that incorporates the strengths, weaknesses, characteristics, and commonalities of the three existing CVP models. It is designed to flexibly adapt depending on the business direction or strategic characteristics of the company by comprehensively considering all circumstances of the entire company or a specific product/service. Additionally, it systematically manages the contents of customers' wants & needs, strategic focus, and growth horizons, even after application. The Integrative-Lean CVP Model, designed for easy use by startups, is expected to help them with limited funding and marketing capabilities identify value proposition elements for timely PMF, fostering the creation of a new startup ecosystem.

A Study on How to Improve Local Government Ordinances to Promote Korean Heritage Information Management : Focusing on the relation aspect of Korean Heritage laws and ordinances (국가유산 정보 관리 활성화를 위한 광역자치단체 조례의 개선 방향 연구 : 국가유산 관련 법과 조례의 관계적 성격을 중심으로)

  • GANG Bobae;JOO Sanghun
    • Korean Journal of Heritage: History & Science
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    • v.57 no.3
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    • pp.140-160
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    • 2024
  • The implementation of the "Basic Law on Korean Heritage" on May 17, 2024, brought about significant changes in the operation of Korean heritage-related ordinances in 17 local governments. This study specifically analyzes the production, collection, and information transfer of Korean heritage information between the Korean Heritage Service and local governments, focusing on the provisions of the law. Finally, in order to achieve the goal of revitalizing the management of Korean heritage information, the study suggests five directions for improvement of the local government ordinance from three perspectives. Firstly, in order to systematize the production of Korean heritage information, it is necessary to specify the entities that produce and manage information in Korean heritage, and to select important Korean heritage information from the information produced and manage it strategically. In today's complex Korean heritage management environment, it is impossible to manage all the Korean heritage information produced by various stakeholders. Secondly, in order to systematize the delivery of Korean heritage information, detailed procedures related to the information to be delivered to the Korean Heritage Service should be specified, and a clear plan for information delivery and management between local and basic local governments should be defined. In the Korean heritage information delivery system, local governments play various roles as direct information providers, managers, consumers, and transmitters. Therefore, it is necessary to specify the provisions of the ordinance so that local governments can systematically fulfill their various roles in the Korean heritage information delivery system. Thirdly, in order to activate the production of Korean heritage information, local governments should review the provisions of the Act to ensure that important Korean heritage information generated from directory provisions and non-mandatory provisions, in addition to the mandatory provisions of the Korean Heritage Act, is not omitted. In particular, Korean heritage information is not just administrative information, but also includes specialized information for the maintenance of the current state of Korean heritage. Therefore, if certain Korean heritage information is partially missing, there may be a gap in intergovernmental communication for Korean heritage management.

Analysis of Waterbody Changes in Small and Medium-Sized Reservoirs Using Optical Satellite Imagery Based on Google Earth Engine (Google Earth Engine 기반 광학 위성영상을 이용한 중소규모 저수지 수체 변화 분석)

  • Younghyun Cho;Joonwoo Noh
    • Korean Journal of Remote Sensing
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    • v.40 no.4
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    • pp.363-375
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    • 2024
  • Waterbody change detection using satellite images has recently been carried out in various regions in South Korea, utilizing multiple types of sensors. This study utilizes optical satellite images from Landsat and Sentinel-2 based on Google Earth Engine (GEE) to analyze long-term surface water area changes in four monitored small and medium-sized water supply dams and agricultural reservoirs in South Korea. The analysis covers 19 years for the water supply dams and 27 years for the agricultural reservoirs. By employing image analysis methods such as normalized difference water index, Canny Edge Detection, and Otsu'sthresholding for waterbody detection, the study reliably extracted water surface areas, allowing for clear annual changes in waterbodies to be observed. When comparing the time series data of surface water areas derived from satellite images to actual measured water levels, a high correlation coefficient above 0.8 was found for the water supply dams. However, the agricultural reservoirs showed a lower correlation, between 0.5 and 0.7, attributed to the characteristics of agricultural reservoir management and the inadequacy of comparative data rather than the satellite image analysis itself. The analysis also revealed several inconsistencies in the results for smaller reservoirs, indicating the need for further studies on these reservoirs. The changes in surface water area, calculated using GEE, provide valuable spatial information on waterbody changes across the entire watershed, which cannot be identified solely by measuring water levels. This highlights the usefulness of efficiently processing extensive long-term satellite imagery data. Based on these findings, it is expected that future research could apply this method to a larger number of dam reservoirs with varying sizes,shapes, and monitoring statuses, potentially yielding additional insights into different reservoir groups.

Analysis of Applicability of RPC Correction Using Deep Learning-Based Edge Information Algorithm (딥러닝 기반 윤곽정보 추출자를 활용한 RPC 보정 기술 적용성 분석)

  • Jaewon Hur;Changhui Lee;Doochun Seo;Jaehong Oh;Changno Lee;Youkyung Han
    • Korean Journal of Remote Sensing
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    • v.40 no.4
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    • pp.387-396
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    • 2024
  • Most very high-resolution (VHR) satellite images provide rational polynomial coefficients (RPC) data to facilitate the transformation between ground coordinates and image coordinates. However, initial RPC often contains geometric errors, necessitating correction through matching with ground control points (GCPs). A GCP chip is a small image patch extracted from an orthorectified image together with height information of the center point, which can be directly used for geometric correction. Many studies have focused on area-based matching methods to accurately align GCP chips with VHR satellite images. In cases with seasonal differences or changed areas, edge-based algorithms are often used for matching due to the difficulty of relying solely on pixel values. However, traditional edge extraction algorithms,such as canny edge detectors, require appropriate threshold settings tailored to the spectral characteristics of satellite images. Therefore, this study utilizes deep learning-based edge information that is insensitive to the regional characteristics of satellite images for matching. Specifically,we use a pretrained pixel difference network (PiDiNet) to generate the edge maps for both satellite images and GCP chips. These edge maps are then used as input for normalized cross-correlation (NCC) and relative edge cross-correlation (RECC) to identify the peak points with the highest correlation between the two edge maps. To remove mismatched pairs and thus obtain the bias-compensated RPC, we iteratively apply the data snooping. Finally, we compare the results qualitatively and quantitatively with those obtained from traditional NCC and RECC methods. The PiDiNet network approach achieved high matching accuracy with root mean square error (RMSE) values ranging from 0.3 to 0.9 pixels. However, the PiDiNet-generated edges were thicker compared to those from the canny method, leading to slightly lower registration accuracy in some images. Nevertheless, PiDiNet consistently produced characteristic edge information, allowing for successful matching even in challenging regions. This study demonstrates that improving the robustness of edge-based registration methods can facilitate effective registration across diverse regions.

The effect of adult learners' motivation to participate in hair education and program satisfaction on lifelong learning happiness index (성인학습자의 헤어교육 참여동기와 프로그램 만족도가평생학습 행복지수에 미치는 영향)

  • Lim Soon Ja
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.5
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    • pp.367-372
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    • 2024
  • It was intended to explore the relationship between motivation for participation in hair education, program satisfaction, and lifelong learning happiness index for adult learners at the Lifelong Education Center, and to provide basic data for revitalizing lifelong education programs. Today, universities have conditions as a comprehensive educational institution with practicality that can meet various and high-quality lifelong educational needs. The university-affiliated Lifelong Education Center plays a role in ensuring the right to learn for all citizens as well as fulfilling the social service function and greatly expanding educational opportunities, which is one of the essential functions of universities, by making good use of the excellent transfer material resources of universities. Adults should now seek professional self-identity through retraining, and respond flexibly to various social situations such as increasing roles, expanding responsibility, and uncertainty in the job and employment structure toward professional socialization in the professional world The subject of the study was to collect data by distributing 90 questionnaires to adult learner hair education subjects in G area, and 85 copies were finally used for SPSS 26.0 for Windows analysis, excluding questionnaires with insufficient responses. The survey period was from November 1 to December 27, 2023. First, it was found that adult learners' motivation to participate in hair education has an effect on the lifelong learning happiness index. Second, it was found that adult learners' satisfaction with the program of hair care workers has an effect on the lifelong learning happiness index. Through this study, it is judged that it is necessary to understand what can maximize the high lifelong learning happiness index, and to meet the learning needs of modern people living in the age of 100, increase their potential, help them design a second life, contribute to self-realization and society, and help them have steady, self-directed lifelong learning opportunities.

Showing Filial Piety: Ancestral Burial Ground on the Inwangsan Mountain at the National Museum of Korea (과시된 효심: 국립중앙박물관 소장 <인왕선영도(仁旺先塋圖)> 연구)

  • Lee, Jaeho
    • MISULJARYO - National Museum of Korea Art Journal
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    • v.96
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    • pp.123-154
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    • 2019
  • Ancestral Burial Ground on the Inwangsan Mountain is a ten-panel folding screen with images and postscripts. Commissioned by Bak Gyeong-bin (dates unknown), this screen was painted by Jo Jung-muk (1820-after 1894) in 1868. The postscripts were written by Hong Seon-ju (dates unknown). The National Museum of Korea restored this painting, which had been housed in the museum on separate sheets, to its original folding screen format. The museum also opened the screen to the public for the first time at the special exhibition Through the Eyes of Joseon Painters: Real Scenery Landscapes of Korea held from July 23 to September 22, 2019. Ancestral Burial Ground on the Inwangsan Mountain depicts real scenery on the western slopes of Inwangsan Mountain spanning present-day Hongje-dong and Hongeun-dong in Seodaemun-gu, Seoul. In the distance, the Bukhansan Mountain ridges are illustrated. The painting also bears place names, including Inwangsan Mountain, Chumohyeon Hill, Hongjewon Inn, Samgaksan Mountain, Daenammun Gate, and Mireukdang Hall. The names and depictions of these places show similarities to those found on late Joseon maps. Jo Jung-muk is thought to have studied the geographical information marked on maps so as to illustrate a broad landscape in this painting. Field trips to the real scenery depicted in the painting have revealed that Jo exaggerated or omitted natural features and blended and arranged them into a row for the purposes of the horizontal picture plane. Jo Jung-muk was a painter proficient at drawing conventional landscapes in the style of the Southern School of Chinese painting. Details in Ancestral Burial Ground on the Inwangsan Mountain reflect the painting style of the School of Four Wangs. Jo also applied a more decorative style to some areas. The nineteenth-century court painters of the Dohwaseo(Royal Bureau of Painting), including Jo, employed such decorative painting styles by drawing houses based on painting manuals, applying dots formed like sprinkled black pepper to depict mounds of earth and illustrating flowers by dotted thick pigment. Moreover, Ancestral Burial Ground on the Inwangsan Mountain shows the individualistic style of Jeong Seon(1676~1759) in the rocks drawn with sweeping brushstrokes in dark ink, the massiveness of the mountain terrain, and the pine trees simply depicted using horizontal brushstrokes. Jo Jung-muk is presumed to have borrowed the authority and styles of Jeong Seon, who was well-known for his real scenery landscapes of Inwangsan Mountain. Nonetheless, the painting lacks an spontaneous sense of space and fails in conveying an impression of actual sites. Additionally, the excessively grand screen does not allow Jo Jung-muk to fully express his own style. In Ancestral Burial Ground on the Inwangsan Mountain, the texts of the postscripts nicely correspond to the images depicted. Their contents can be divided into six parts: (1) the occupant of the tomb and the reason for its relocation; (2) the location and geomancy of the tomb; (3) memorial services held at the tomb and mysterious responses received during the memorial services; (4) cooperation among villagers to manage the tomb; (5) the filial piety of Bak Gyeong-bin, who commissioned the painting and guarded the tomb; and (6) significance of the postscripts. The second part in particular is faithfully depicted in the painting since it can easily be visualized. According to the fifth part revealing the motive for the production of the painting, the commissioner Bak Gyeongbin was satisfied with the painting, stating that "it appears impeccable and is just as if the tomb were newly built." The composition of the natural features in a row as if explaining each one lacks painterly beauty, but it does succeed in providing information on the geomantic topography of the gravesite. A fair number of the existing depictions of gravesites are woodblock prints of family gravesites produced after the eighteenth century. Most of these are included in genealogical records and anthologies. According to sixteenth- and seventeenth-century historical records, hanging scrolls of family gravesites served as objects of worship. Bowing in front of these paintings was considered a substitute ritual when descendants could not physically be present to maintain their parents' or other ancestors' tombs. Han Hyo-won (1468-1534) and Jo Sil-gul (1591-1658) commissioned the production of family burial ground paintings and asked distinguished figures of the time to write a preface for the paintings, thus showing off their filial piety. Such examples are considered precedents for Ancestral Burial Ground on the Inwangsan Mountain. Hermitage of the Recluse Seokjeong in a private collection and Old Villa in Hwagae County at the National Museum of Korea are not paintings of family gravesites. However, they serve as references for seventeenth-century paintings depicting family gravesites in that they are hanging scrolls in the style of the paintings of literary gatherings and they illustrate geomancy. As an object of worship, Ancestral Burial Ground on the Inwangsan Mountain recalls a portrait. As indicated in the postscripts, the painting made Bak Gyeong-bin "feel like hearing his father's cough and seeing his attitudes and behaviors with my eyes." The fable of Xu Xiaosu, who gazed at the portrait of his father day and night, is reflected in this gravesite painting evoking a deceased parent. It is still unclear why Bak Gyeong-bin commissioned Ancestral Burial Ground on the Inwangsan Mountain to be produced as a real scenery landscape in the folding screen format rather than a hanging scroll or woodblock print, the conventional formats for a family gravesite paintings. In the nineteenth century, commoners came to produce numerous folding screens for use during the four rites of coming of age, marriage, burial, and ancestral rituals. However, they did not always use the screens in accordance with the nature of these rites. In the Ancestral Burial Ground on the Inwangsan Mountain, the real scenery landscape appears to have been emphasized more than the image of the gravesite in order to allow the screen to be applied during different rituals or for use to decorate space. The burial mound, which should be the essence of Ancestral Burial Ground on the Inwangsan Mountain, might have been obscured in order to hide its violation of the prohibition on the construction of tombs on the four mountains around the capital. At the western foot of Inwangsan Mountain, which was illustrated in this painting, the construction of tombs was forbidden. In 1832, a tomb discovered illegally built on the forbidden area was immediately dug up and the related people were severely punished. This indicates that the prohibition was effective until the mid-nineteenth century. The postscripts on the Ancestral Burial Ground on the Inwangsan Mountain document in detail Bak Gyeong-bin's efforts to obtain the land as a burial site. The help and connivance of villagers were necessary to use the burial site, probably because constructing tombs within the prohibited area was a burden on the family and villagers. Seokpajeong Pavilion by Yi Han-cheol (1808~1880), currently housed at the Los Angeles County Museum of Art, is another real scenery landscape in the format of a folding screen that is contemporaneous and comparable with Ancestral Burial Ground on the Inwangsan Mountain. In 1861 when Seokpajeong Pavilion was created, both Yi Han-cheol and Jo Jung-muk participated in the production of a portrait of King Cheoljong. Thus, it is highly probable that Jo Jung-muk may have observed the painting process of Yi's Seokpajeong Pavilion. A few years later, when Jo Jungmuk was commissioned to produce Ancestral Burial Ground on the Inwangsan Mountain, his experience with the impressive real scenery landscape of the Seokpajeong Pavilion screen could have been reflected in his work. The difference in the painting style between these two paintings is presumed to be a result of the tastes and purposes of the commissioners. Since Ancestral Burial Ground on the Inwangsan Mountain contains the multilayered structure of a real scenery landscape and family gravesite, it seems to have been perceived in myriad different ways depending on the viewer's level of knowledge, closeness to the commissioner, or viewing time. In the postscripts to the painting, the name and nickname of the tomb occupant as well as the place of his surname are not recorded. He is simply referred to as "Mister Bak." Biographical information about the commissioner Bak Gyeong-bin is also unavailable. However, given that his family did not enter government service, he is thought to have been a person of low standing who could not become a member of the ruling elite despite financial wherewithal. Moreover, it is hard to perceive Hong Seon-ju, who wrote the postscripts, as a member of the nobility. He might have been a low-level administrative official who belonged to the Gyeongajeon, as documented in the Seungjeongwon ilgi (Daily Records of Royal Secretariat of the Joseon Dynasty). Bak Gyeong-bin is presumed to have moved the tomb of his father to a propitious site and commissioned Ancestral Burial Ground on the Inwangsan Mountain to stress his filial piety, a conservative value, out of his desire to enter the upper class. However, Ancestral Burial Ground on the Inwangsan Mountain failed to live up to its original purpose and ended up as a contradictory image due to its multiple applications and the concern over the exposure of the violation of the prohibition on the construction of tombs on the prohibited area. Forty-seven years after its production, this screen became a part of the collection at the Royal Yi Household Museum with each panel being separated. This suggests that Bak Gyeong-bin's dream of bringing fortune and raising his family's social status by selecting a propitious gravesite did not come true.

Effects of Some Physico-Chemical Conditions of Sioil on Growth and Ionic Balance of the Tobacco Plant (Nicotiana Tabacum L.) I. Effect of Acidity(pH), Moisture(pF) and Anions (Cl-, SO4-) in Soil on Grwth and Ionic Balance of Tobacco (토양(土壤)의 몇가지 이화학적조건(理化學的條件)이 연초(煙草)의 생육(生育) 및 이온평형(平衡)에 미치는 영향(影響) I. 토양(土壤)의 pH, pF와 음(陰)이온(Cl-, SO4-)이 연초(煙草)의 생육(生育) 및 이온평형(平衡)에 미치는 영향(影響))

  • Kim, Jai-Jong;Cho, Seong-Jin
    • Korean Journal of Soil Science and Fertilizer
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    • v.14 no.3
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    • pp.117-129
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    • 1981
  • An experiment with the tobacco plant was conducted in the pots. A sandy humic soil was used with 2 levels of pH, 3.5 and 5.8 with 2 kinds of anions, Cl as $NH_4Cl$ and $SO_4$ as $(NH_4)_2SO_4$, and with 4 levels of pF, 1.5, 2.0, 2.5, and 3.5. The pH-treatment created different N-forms; $NH_4$ at low pH(3.5) and $NO_3$ at high pH (5.8). The results are summarized as follows: 1. At low pH (3.5) with high concentration of $NH_4$ given as $NH_4Cl$, the high content of $NH_4$ and Cl in tobacco resulted in plants suffering from $NH_4$ and Cl toxicity as well as Mn toxicity. As a result of these toxicity, an extremly abnormal growth of tobacco was clearly appeared. In the tobacco grown at low pH with $NH_4$ given as $(NH_4)_2SO_4$, a large amount of the $NH_4$ uptake developed Mg and Ca deficiencies. $NH_4-N$, which had been applied to the soil of high pH (5.8), was almost completely transformed into $NO_3-N$ by nitrification and, on this low acidic soil, the plants were all healthy regardless of Cl or $SO_4$ added together with $NH_4-N$. However, dry matter production was higher and maturity faster when $SO_4$ was used as anion than when Cl was used. 2. High moisture content in soil, to some extent, is necessary for a good development and growth of the tobacco plant. Phosphate uptake seemed to be limited at higher moisture stress. The dry matter yield of tops and roots of tobacco were in the order of pF 1.8 > 2.1 > 2.6 > 3.6, respectively. 3. Data of chemical analysis and dry matter yields of tops and roots showed that the tobacco plant followed the normal (C-A) concept. In the normal growth of plants, the carboxylate content of tops was quite comparable to the estimated (C-A) values. If $NH_4$ content of plants remains in quite high quantities, it must be analysed and taken into consideration for the (C-A) calculation. Al is not transported toward tops in toxic amounts due to its high immobility, it mostly stay in or on the roots, probably due to precipitation as a aolt. When Al is present in high quantities, it has to be considered into the (C-A) calculation.

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