• Korean Journal of Organic Agriculture
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• v.9 no.2
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• pp.101-115
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• 2001

Nitrogen applied as fertilizer for crop production is partly absorbed by plant , and the remaining nitrogen in soil might be leached out through complicated processes to the subsoil layer Especially, NO$_3$-N in leachate causes environmental pollution. The purpose of this study was focused on understanding of uptake of nutrients by plants, the behaviors of nutrients in soil and the possibility of leaching loss when nitrogen fertilizer and completely decomposed compost were applied. Lysimeters(Volume 0.15㎥, Diameter 62cm, Height 62.8cm) were installed for collecting leachate in the Jeju volcanic ash soils. Lysimeter study consisted of thirteen treatments : fallow, fallow with weeding, cropping without fertilizer and compost, three N fertilizer soil surface applications(16, 32, 64kg/10a), three N fertilizer and compost soil surface applications(16+800, 32+1600, 64+32kg/10a), two water dissolved N fertilizer applications(16, 32kg/10a), and low and high plant densities. N fertilizer was applied as urea. The growth of com(preceding crop) and potatoes(succeeding crop) and leaching loss were determined during the experimental period. The results obtained were summarized as follows ; With Increased N, pH of leachate tended to decrease and NO$_3$-N concentration of leachate increased. NO$_3$-N leaching loss was remarkably greater in soil from the bare plot without fertilization and the weed control than from plots with medium N rate and was least in the cropping plot without fertilization. NO$_3$-N concentration in leachates from the water dissolved N fertilizer application plots was 64% of that from the soil surface application plots. The concentration of Ca and K ions and the leaching loss of these ions were least from the cropping plot without fertilization and were greatest from bare plots(T1 and T2) without fertilization. The proportion of leaching and residual N in soil increased as N rate increased indicting that higher N rates increase the possibility of N leaching to subsoil layer The proportion of N leaching losses was lower at the low N rate and the high plant density. In future, fertilization prescription which can maximize fertilizer use efficiency and minimize the pollution of ground water will be needed for conserving the environments.

• KDI Journal of Economic Policy
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• v.30 no.2
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• pp.129-155
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• 2008

The rate of antibiotics prescription for an acute airway infection significantly varies depending upon the diagnosis type, specialty, and the location of the hospital along with many other related factors. The objective of this study is to empirically investigate the possible relationship between the antibiotics prescription rates for an acute airway infection and the degree of competition in the hospital market regions of mainly the providers of primary medical care services such as clinics, internal medicines, pediatrics and otorhinolaryngology department. Using the data from Health Insurance Review and Assessment Service (HIRA) regarding the hospitals' antibiotics prescription rates for the acute airway infection and controlling for selected variables of demand and supply sectors, this study tries to figure out that the degree of competition in the hospital market, regardless of what type of competition indexes we employed, has a statistically significant effect on the variations of antibiotics prescription rate of the clinics in local areas. This result implies that as an economic consideration itself, the change in the degree of competition in the hospital market can play a crucial role influencing the treatment behaviors of the medical doctors. More specifically, this study reveals that as the degree of competition increases the antibiotics prescription rate goes up. This result means that if the market becomes more competitive in a specific region so that it might cause a reduction in doctor's income, doctors with rational decision-making process, recognize that the benefit created from inducing patients' seemingly unnecessary demand for medical care (income effect) would be higher than the costs associated with sustaining their targeted income (substitution effect). It is because that the doctors are more likely to prescribe antibiotics which create relatively higher margins than other medical care services in order to sustain their targeted income when the hospital market competition becomes tighter. Even though this study empirically confirms that antibiotics prescription can be affected by the economic incentives, it still raises following issues as limitations of the study: first issue is about the representativeness of the hospital regions segregated for this study, which might be weak in explaining whether these regions are mutually exclusive in reality. Patients actually consider the quality of services, transportation cost, time costs, and any other related factors choosing the doctors or hospitals, and in that sense, this study rules out 'border-crossing' in using the medical care services. Second issue arises in capturing the data of antibiotics prescription rate. Since we use the average rate for each medical institution, we cannot figure out the average rate for each patient so that we are not able to control for the variation of patients' medical conditions. It is because of the unavailability of data regarding each patient's medical condition from HIRA. Thirdly, since this study mainly analyzes the medical institutions providing primary care such as clinics, internal medicines, pediatrics, and otorhinolaryngology department, it is skeptical of whether those institutions can represent the hospital market in respective regions and truly reflect the degree of competition. It needs to extend the study areas and disease types as well as any micro data for future studies.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.1
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• pp.23-33
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• 2012

In this study, how much users of Hannamkeumbuk Keumbuk Mountains are aware of Baekdaegan and its attached mountain chains, a traditional geographic system, according to Sangyungpyo and basic data like the degree of awareness and use-behaviors, etc. have been studied. In addition, the environmental value of Hannamkeumbuk Keumbuk Mountains separating the central and the southern part of Korea among attached mountain ranges, secondary mountain chains, which act as an ecosystem buffer in the Baekdudaegan Range, has been estimated at the current amount of currency. In the questions of the perception of the traditional classification standard of mountain chains and Baekdudaegan, more than 70% of respondents answered that they had heard of or known them but 66.8% werenot aware of Hannamkeumbuk Keumbuk Mountains. While the awareness for Baekdudaegan is high, the perception of its attached mountain chains was very poor. DBDC responder system and CVM, which is used widely for the value estimate method of environment goods, were used. As the result, an additional benefit got when a person visits Hannamkeumbuk Keumbuk mountains was estimated as 5,813 won. It could find out that this amount was very low compared with 51,984 won, average visit cost. It judged that the reason was that damage of environmental conditions, the monotony of the trails and progress of indiscriminate environmental destruction, etc. The results of this study will offer a new perspective on public relations activities and resource conservation of Baekdudaegan and its attached mountain chains and estimate perceptions and efficient services for visitors to HannamKeumbuk Keumbuk Mountains. This study will act as data for basic planning and management to increase the mountains' value and to preserve them. Further studies are needed to make a frame of work division and management with various organizations so that the management of Hannamkeumbuk-Keumbuk Mountains may be properly established and their value may been hanced.

• Journal of Intelligence and Information Systems
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• v.18 no.1
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• pp.125-141
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• 2012

These days, the malicious attacks and hacks on the networked systems are dramatically increasing, and the patterns of them are changing rapidly. Consequently, it becomes more important to appropriately handle these malicious attacks and hacks, and there exist sufficient interests and demand in effective network security systems just like intrusion detection systems. Intrusion detection systems are the network security systems for detecting, identifying and responding to unauthorized or abnormal activities appropriately. Conventional intrusion detection systems have generally been designed using the experts' implicit knowledge on the network intrusions or the hackers' abnormal behaviors. However, they cannot handle new or unknown patterns of the network attacks, although they perform very well under the normal situation. As a result, recent studies on intrusion detection systems use artificial intelligence techniques, which can proactively respond to the unknown threats. For a long time, researchers have adopted and tested various kinds of artificial intelligence techniques such as artificial neural networks, decision trees, and support vector machines to detect intrusions on the network. However, most of them have just applied these techniques singularly, even though combining the techniques may lead to better detection. With this reason, we propose a new integrated model for intrusion detection. Our model is designed to combine prediction results of four different binary classification models-logistic regression (LOGIT), decision trees (DT), artificial neural networks (ANN), and support vector machines (SVM), which may be complementary to each other. As a tool for finding optimal combining weights, genetic algorithms (GA) are used. Our proposed model is designed to be built in two steps. At the first step, the optimal integration model whose prediction error (i.e. erroneous classification rate) is the least is generated. After that, in the second step, it explores the optimal classification threshold for determining intrusions, which minimizes the total misclassification cost. To calculate the total misclassification cost of intrusion detection system, we need to understand its asymmetric error cost scheme. Generally, there are two common forms of errors in intrusion detection. The first error type is the False-Positive Error (FPE). In the case of FPE, the wrong judgment on it may result in the unnecessary fixation. The second error type is the False-Negative Error (FNE) that mainly misjudges the malware of the program as normal. Compared to FPE, FNE is more fatal. Thus, total misclassification cost is more affected by FNE rather than FPE. To validate the practical applicability of our model, we applied it to the real-world dataset for network intrusion detection. The experimental dataset was collected from the IDS sensor of an official institution in Korea from January to June 2010. We collected 15,000 log data in total, and selected 10,000 samples from them by using random sampling method. Also, we compared the results from our model with the results from single techniques to confirm the superiority of the proposed model. LOGIT and DT was experimented using PASW Statistics v18.0, and ANN was experimented using Neuroshell R4.0. For SVM, LIBSVM v2.90-a freeware for training SVM classifier-was used. Empirical results showed that our proposed model based on GA outperformed all the other comparative models in detecting network intrusions from the accuracy perspective. They also showed that the proposed model outperformed all the other comparative models in the total misclassification cost perspective. Consequently, it is expected that our study may contribute to build cost-effective intelligent intrusion detection systems.

• Journal of muscle and joint health
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• v.2 no.1
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• pp.17-40
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• 1995

Rheumatoid arthritis is the one of the chronic diseases, one of its major symptoms is a chronic pain. Despite developing medical treatment and surgical techniques, it is suggested that to control the pain is the goal of the treatment. But pain is an inner experience and even those closest to the patient cannot truly observe its progress or share in its suffering. The National Academy of Sciences Institute of Medicine's report on Pain and Disability concluded that there is no objective measure of pain-(exactly) no pain thermometer-nor can there ever be one, because the experience of pain is inseparable from personal perception and social influence such as culture. To explore chronic pain experience is to understand the process and property of the patient's perception of pain through the response to pain, the coping with pain, and the adaptation to pain. Therefore a qualitative study was conducted in order to gain an understanding of pain experience of patients with RA in korea. I used naturalistic inquiry as a research methodology, which had 5 axioms, the first is that realities are multiple, constructed, and holistic, the second is that knower and known are interactive, inseparable, the third is only time and context bound working hypotheses(idiographic statements) are possible, the forth is all entities are in a state of mutual simultaneous shaping, so that it is impossible to distinguish causes from effects and the last is that inquiry is value-bound. Purposive sampling was conducted as a sampling. 20 subjects who experienced pain over 10 years, lived in middle-sized city and big city in Korea, and 17 women and 3 men. The subject's age was from 32 to 62 (average 48.8), all were married, living with their spouse and children, except two-one divorced and the other widow before they became ill. I collected data using In depth structured interview. I had interviews two or three times with each subject, and the interviews were conducted at each subject's home. Each interview lasted about two hours an average. A recording was taken with the consent of the subject. I used inductive data analysis-such as unitizing and categorizing. unitizing is a process of coding, whereby raw data are systematically transformed and aggregated into units. Categorizing is a process wherby previously unitized data are organized into categories that provide descriptive or inferential information about the context or setting from which the units were derived. This process is used constant comparative method. The pain controlling process is composed of behavior of pain control. The behaviors of pain control are rearranging of ADL, hiddening role conflict, balancing treatment, and changing social relation. Rearranging of ADL includes diet management, sleep management, and the adjustment of daily life activities. The subjects try to rearrange their daily activities by modified style of motions, rearranging time span & range of activities, using auxillary facilities, and getting help in order to keep on the pace of daily life. Hiddening role conflict means to reduce conflicts between sick role and their role as a family member. In this process, the subjects use two modes, one is to control the pain complaints, and the other is to internalize the value which is to stay home is good for caring her children and being a good mother. To control pain complaints is done by 'enduring', 'understanding' the other family members, or making them undersood in order to reduce pain. Balancing treatment is composed of two aspects. One is to keep the pain within the endurable level, the other is to keep in touch with medical personnel in order to get the information of treatment and emotional support. Changing social relation is made by information seeking and sharing, formation of mutual support relation, and finally simplification of social relationships. The subjects simplify their social relationships by refraining from relations with someone who makes them physically and psychologically strained. In particular the subjects are apt to avoid contact with in-laws, and the change of relation to in-laws results in lessening the family boundary. In the course of this process, they confront the crisis of family confict result in family dissolution. This crisis is related to the threat of self-existence. Findings from this study contribute to understanding the chronic pain experience. To advance this study, we should compare this result with other cases in different cultural contexts. I think to interpret these results, korean cultural background should be considered. Especially the different family concept, more broader family members and kinship network, and the traditional medical knowledge influences patients' behavior.

• Asia pacific journal of information systems
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• v.19 no.4
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• pp.101-124
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• 2009

According to Wikipedia, virtual reality (VR) is defined as a technology that allows a user to interact with a computer-simulated environment. Due to a rapid growth in information technology (IT), the cost of virtual reality has been decreasing while the utility of virtual reality advertisements has dramatically increased. Nevertheless, only a few studies have investigated the effects of virtual reality advertisement on consumer behaviors. Therefore, the objective of this study is to empirically examine the effects of virtual reality advertisement. Compared to traditional online advertisements, virtual reality advertisement enables consumers to experience products realistically over the Internet by providing high media richness, interactivity, and telepresence (Suh and Lee, 2005). Advertisements with high media richness facilitate consumers' understanding of advertised products by providing them with a large amount and a high variety of information on the products. Interactivity also provides consumers with a high level of control over the computer-simulated environment in terms of their abilities to adjust the information according to their individual interests and concerns and to be active rather than passive in their engagement with the information (Pimentel and Teixera, 1994). Through high media richness and interactivity, virtual reality advertisements can generate compelling feelings of "telepresence" (Suh and Lee, 2005). Telepresence is a sense of being there in an environment by means of a communication medium (Steuer, 1992). Virtual reality advertisements enable consumers to create a perceptual illusion of being present and highly engaged in a simulated environment, while they are in reality physically present in another place (Biocca, 1997). Based on the characteristics of virtual reality advertisements, a research model has been proposed to explain consumer responses to the virtual reality advertisements. The proposed model includes two dimensions of consumer responses. One dimension is consumers' rational response, which is based on the Information Processing Theory. Based on the Information Processing Theory, product knowledge and perceived risk are selected as antecedents of intention to purchase. The other dimension is emotional response of consumers, which is based on the Attitude-Structure Theory. Based on the Attitude-Structure Theory, arousal, flow, and positive affect are selected as antecedents of intention to purchase. Because it has been criticized to have investigated only one of the two dimensions of consumer response in prior studies, our research model has been built so as to incorporate both dimensions. Based on the Attitude-Structure Theory, we hypothesized the path of consumers' emotional responses to a virtual reality advertisement: (H1) Arousal by the virtual reality advertisement increases flow; (H2) Flow increases positive affect; and (H3) Positive affect increases intension to purchase. In addition, we hypothesized the path of consumers' rational responses to the virtual reality advertisement based on the Information Processing Theory: (H4) Increased product knowledge through the virtual reality advertisement decreases perceived risk; and (H5) Perceived risk decreases intension to purchase. Based on literature of flow, we additionally hypothesized the relationship between flow and product knowledge: (H6) Flow increases product knowledge. To test the hypotheses, we conducted a free simulation experiment [Fromkin and Streufert, 1976] with 300 people. Subjects were asked to use the virtual reality advertisement of a cellular phone on the Internet and then answer questions about the variables. To check whether subjects fully experienced the virtual reality advertisement, they were asked to answer a quiz about the virtual reality advertisement itself. Responses of 26 subjects were dropped because of their incomplete answers. Responses of 274 subjects were used to test the hypotheses. It was found that all of six hypotheses are accepted. In addition, we found that consumers' emotional response has stronger impact on their intention to purchase than their rational response does. This study sheds much light into practical implications for both IS researchers and managers. First of all, while most of previous research has analyzed only one of the customers' rational and emotional responses, we theoretically incorporated and empirically examined both of the two sides. Second, we empirically showed that mediators such as arousal, flow, positive affect, product knowledge, and perceived risk play an important role between virtual reality advertisement and customer's intention to purchase. In addition, the findings of this study can provide a basis of practical strategies for managers. It was found that consumers' emotional response is stronger than their rational response. This result indicates that advertisements using virtual reality should focus on the emotional side, and that virtual reality can be served as an appropriate advertisement tool for fancy products that require their online advertisements to give an impetus to customers' emotion. Finally, even if this study examined the effects of virtual reality advertisement of cellular phone, its findings could be applied to other products that are suited for virtual experience. However, this research has some limitations. We were unable to control different kinds of consumers and different attributes of products on consumers' intention to purchase. It is, therefore, deemed important for future research to control the consumer and product types for more reliable results. In addition to the consumer and product attributes, other variables could affect consumers' intention to purchase. Thus, the future research needs to find ways t control other variables.

• (The)Study of the Eastern Classic
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• no.71
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• pp.231-258
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• 2018

This paper examines the differences of two different versions of "Cheonuisogameonhae" in terms of stylistics and investigates factors affecting the differences. The interpretations between the woodblock edition and the manuscript edition might be different depending on assumed range of readership, and the stylistic differences between two editions might be different depending on the possibility of extension of the reading population. Thus, this paper examines how stylistic effects are reflected in inter-relations between a translator as a speaker and readers as listeners according to speaker intentions. In Chapter 2, the stylistic differences reflected from two difference editions are examined in terms of the expression of a writer's respect, emotions, and formal consciousness to readers. The expressions of a writer's respect are more clearly emerged in the manuscript edition than in the woodblock edition. The honorific expression of a subject, '-gyeo?dsyeo', and the honorific expression of a writer, '-s?p-', are more frequently used in the manuscript edition than in the woodblock edition. In order to express positive emotions, exclamation endings are used in the manuscript edition, which shows the writer's strong emotional sympathy with readers' words and behaviors. On the other hand, in the woodblock edition, '-이' is used after names in order to treat rebellious subjects and people involved in conspiracy contemptuously by the use of informal forms. In addition, affirmative sentences in the manuscript edition and double negative sentences in the woodblock edition are used respectively, which intends to strongly emphasize a king's will and the appropriateness of the will. The writer's formal consciousness to readers are found in the way of writing names of people and places in Korean. Chinese characters are generally used two show formal consciousness; thus, names of people and places are expressed in Chinese characters in the woodblock edition. In Chapter 3, factors that made the stylistic differences between two editions are examined. The factors causing stylistic differences are examined in terms of the purpose of the interpretation, the class and range of the reading population, a writer's attitudes toward readers, and the face-to-fact situation of a writer and readers.

• Journal of Korean Classical Literature and Education
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• no.34
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• pp.41-74
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• 2017

This study aimed to investigate the narrative strategy and meaning of fantasy in classic novels and to derive the educational meaning from the fantasy of Sukhyangjeon. This study selected Sukhyangjeon because is considered a suitable literary text that embodies characteristics of fantasy inherent in classical novels through its successful portrayal of the fantasy genre and its high popularity during its time. Specifically, this study observed that the "notice of hardships" which repeatedly appears in the narration of Sukhyangjeon reinforces the fantasy of the novel as it serves as an advance notice of intervention from heaven. Therefore, this study investigated the relationship between the notice of hardships and fantasy by focusing on Sukhyang's life. The way in which the "notice of hardships" is a form of illusion realized it evident in the plot when heaven saves Sukhyang from her hardship even though it was heaven that had granted her those forms of hardship. Firstly, the "notice from heaven" constitutes the macro structure of Sukhyangjeon. Through it, readers realize the enormous power of heaven by seeing how Sukhyang's life has been realized in accordance with heaven's notice with that, it evokes a sense of respect to heaven. In addition, heaven saves Sukhyang from different forms of danger. It enhances a miraculous feeling, which the omnipotent power of heaven shows, against the innocent appearance of Sukhyang during her times of danger. Meanwhile, when heaven notifies Sukhyang and the surrounding people of their fate and subsequently realizes it through dreams, this act creates a mysterious atmosphere and improves the probability of the narrative. If so, the narrative meaning in reinforcing the fantasy of the novel by the use of "notice of hardships" could be revealed through Sukhyang's real life. First, the hardship in which Sukhyang has gone through is so realistic and detailed that the readers' feelings of empathy are evoked with the fear of the coming hardship, wailing together, and trying to resolve the inner anxiety through Sukhyang's happiness. Second, the heavenly beings who are touched by the good behaviors of Sukhyang save her from the dangers of death. This creates the belief in readers that heaven intervenes for the good people. Third, the active attitude that Sukhyang and Leesun show in the process of marriage helps them overcome their earthly hardship and preserve their relationship in heaven. This gives readers hope that they could go to a "higher life" after going through suffering. This fantasy of Sukhyangjeon helps readers overcome their anxieties of reality through fantasy and recognizes the importance of relationships to enhance a sense of unity and solidarity with others. Because of these elements, it is expected that the fantasy of Sukhyangjeon will have a meaningful value to modern readers.

• Korean Journal of Heritage: History & Science
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• v.47 no.1
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• pp.32-45
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• 2014

In this study, the characteristics of Mongsimjae in Namwon-si, Jeollabuk-do have been researched focusing on the writings engraved in huge stones and rocks of pavilion standing beside a lotus pond and its formative languages in the garden has been interpreted as follows. Name of pavilion(堂號) Mongsimjae(夢心齋) includes a classical scholar's spirit, refusing to serve two kings and homecoming after resignation from a government office(歸去來) of Songam(松菴) Park Moonsu(朴門壽), an ancestor who has brought to the Juksan(竹山) Park's family again. A pavilion standing beside a lotus pond(蓮塘) built in the reception garden is a gardening facility symbolizing 'Yeondang(蓮堂)' Park Dongsik(朴東式) who built Mongsimjae. The bamboo hill connected to the backyard seems to be relevant to 'Juksan', the family clan of Mongsimjae's owner and this kinds of intention can be found in the bamboos in the outer garden naturally led to inside the garden through the flower beds. The purpose for the western arrangement of the main building and gate contrary to the 'chukjwamihyaug'(丑坐未向; a direction toward to the south-southwest) of the prospect of Sarangchae(guesthouse) is interpreted to naturally attract people's eyes to the pavilion standing beside a lotus pond and to mitigate the sense of closure resulting from the huge stones located in the reception garden. Also the writing engraved in the three huge stones, 'Jonsimdae(存心臺)', implies that it is a place where was selected with heart by Juksan Park family who settled down in Homsil, Namwon after 'Haengchon(杏村) Park Jaryang(朴子良)' in Yiphyangjo(入鄕祖), Namwon and 'Jeongwa(靖窩)' is interpreted as a signature representing that it is the most comfortable house where Jeongwa Park Haechang(朴海昌: 1876~1933), the third owner of Mongsimjae, has lived. The pavilion standing beside a lotus pond of the 'Bangjibangdo(方池方島; square pond and square island)' type has no lotus for now and waterside cornerstones roughly piled with broken stones naturally mitigate the slope. There are two water inflows gathering rainwater in the reception garden other than the water inflow of valley and the upper-side water inflow was built using a high waterfall method. The middle island cut into a square was designed to use in two ways, as 'island' or 'steppingstone', according to the water level and the old name of the pavilion standing beside a lotus pond was revealed as 'Cheonundam(天雲潭)' from the engraved writing located in the side of the middle island. In addition, 'Imni(臨履)', engraved writing in the finishing stone of waterside by citing a line of 'Sigyeong(詩經)', implies 'Be a upright classical scholar who pays close attention to one's own behaviors' and 'Jeongchuk(渟?)' is interpreted as a message that desires the eternal staying of the Juksan Park family's wealth. Ultimately, the writings engraved in the huge stones and rocks of the pavilion standing beside a lotus pond are interpreted as a symbol language that wishes the heaven protects and maintains the wealth of the Juksan Park family who is the owner of Mongsimjae.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.243-250
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• 2018

BACKGROUND: Recently, the use of $^{131}I$ for diagnosis and treatment of thyroid cancer has been increasing, and the radionuclide is continuously released into aquatic ecosystem. This study was carried out to investigate the $^{131}I$ concentrations in mainstreams, tributaries, and sewage wastewater treatment plants (SWTPs) of the Yeongsan River Basin and to identify their origins from the assessment of behaviors in the rivers. METHODS AND RESULTS: The water samples were collected from 19 sites including mainstreams (13), tributaries (4) and SWTPs (2). The $^{131}I$ concentration was measured using a gamma-ray spectrometry with a HPGe detector. The $^{131}I$ in SWTPs was detected mostly in the discharged effluent at the sampling sites. However, from the surface water of the rivers, $^{131}I$ was found only at two sites from each sampling period of the first (MS4 and MS10) and the second half (MS4 and MS7) of the year 2017. The concentrations of $^{131}I$ in the effluent discharged from SWTPs were in the range of 0.0870 to 3.87 Bq/L for SWTP1, and $^{131}I$ in the river revealed that it was not detected in the upper streams of the mainstreams and tributaries, while continuous detection was found in the SWTPs and downstream sites affected by the effluent. However, the concentration of $^{131}I$ decreased downstream, eventually becoming undetectable. Such behavior was closely related to the behavior found in the SWTPs. CONCLUSION: These results indicated that medically-derived $^{131}I$ was discharged to the river via sewage effluent at the SWTPs. It is necessary to evaluate the influence of aquatic ecosystems through continuous monitoring in the future.