• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.422-430
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• 2000

Three-year-old Pinus koraiensis seedlings, transplanted in brown forest soils originating from granite were treated with simulated acid rain of pH concentrations 5.6(control), 4.0, 3.0, 2.5 and 2.0 for 210 days from April 21 to November 17, 1999. Visible injury of the seedlings were observed at the pH 2.0 and pH 2.5 treatments. The total dry weight of the seedlings decreased at pH 2.0 treatment compared with that of the control, and T/R ratio increased at pH 2.0 treatment compared with others. The elements in each part of the seedlings, concentrations of Ca, P and content of chlorophyll in needles increased at the pH 2.0 treatment compared with the control. The concentration of N in the needles of the seedlings increased as the soil pH decreased. As the treated pH was lowered, soil pH has decreased, and concentrations of Ca, Mg, Al, and Mn increased, especially at pH 4.4. In addition, there was a strong correlation(r=0.90, p<0.05 ; r=-0.94, p<0.01) between the dry weight of the seedlings and the pH and Al concentration of the soils. Therefore, the pH and Al concentration in the soil may be useful indicator for assessing the effect of acid rain on the growth of woody plants.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.1
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• pp.25-39
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• 1986

In this paper, we analyze the performance, particularly the flow control mechanism, of the CCITT X.25 protocol in a packet-switched network. In this analysis, we consider the link and packet layers separately, and investigate the performance in three measures; normalized channel throughput, mean transmission time, and transmission efficiency. Each of these measures is formulated in terms of given protocol parameters such as windos size, $T_1$ and $T_2$ values, message length, and so forth. We model the service procedure of the inpur traffic based on the flow control mechanism of the X.25 protocol, and investigate the mechanism of the sliding window flow control with the piggybacked acknowlodgment scheme using a discrete-time Markov chain model. With this model, we study the effect of variation of the protoccol parameters on the performance of the X.25 protocol. From the numerical results of this analysis one can select the optimal valuse of the protocol parameters for different channel environments. it has been found that to maintain the trasnmission capacity satisfactorily, the window size must be greater than or equal to 7 in a high-speed channel. The time-out value, $T_1$, must carefully be selected in a noisy channel. In a normal condition, it should be in the order of ls. The value of $T_2$ has some effect on the transmission efficiency, but is not critical.

• KDI Journal of Economic Policy
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• v.33 no.4
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• pp.85-118
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• 2011

This paper uses the horizontal regulation system as the base analysis framework. The study clearly defines the regulatory goals of the followings: the horizontal cross-ownership regulations on program provider (PP) and platform provider, the vertical regulation on cross-ownership between PP and platform operator, the regulation on cross-ownership of program provider by terrestrial broadcasting company, and the regulation on cross-ownership between terrestrial broadcasting company and platform provider. Then, by analyzing the conformity between goals and criteria of regulations and the adequacy of the regulation level according to regulatory purposes, this paper examines the justifiability of each regulation and extracts improvement measures that suite regulatory purposes. This analysis finds following appropriate measures: replacing the horizontal cross-ownership regulation on PP with conduct regulations, such as designating major broadcasting programs or replacing the current criterion of cross-ownership regulation from sales to the audience market share; reshaping the horizontal cross-ownership regulation on platform provider so that system operator (SO), satellite broadcaster and Internet protocol television (IPTV) operator would be applied by the same regulation based on the number of subscribers of pay television services; and discontinuing other cross-ownership regulation. In this way, the study shows that with appropriate regulations on cross-ownership of PP, there would be no need for additional regulation on vertical integration between PP and platform operator. On the other hand, given that the regulation on terrestrial broadcasting cross-ownership of PP could be justified only by regulatory purpose of the protection of the diversity of public opinions, it would be desirable to replace the current criteria of the number of PPs with the criteria of the audience market share. Lastly, the study shows that when platform operator is targeted by the cross-ownership regulation based on the number of subscribers of pay television services, the regulation on cross-ownership between terrestrial broadcasting company and platform provider should be replaced with conduct regulations, such as designating must-offer channels and major broadcasting programs.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.2
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• pp.145-151
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• 2008

The research so far has primarily analyzed efficiency improvement but in this research, it analyzes the characteristics of earthquake behavior, with changed pier heights, through ordinary and seismic analysis. For this, the kind of bridge bearing has been changed against PSC I-shaped bridge, which is mostly used in practice, and at all times earthquake analysis has been performed with through height of pier. Especially considering sectional power resulting from earthquake analysis, displacement of PSC I-shaped bridge bearing, diameter of pier pillar by earthquake load, and upper spare gap have been analyzed. In case of high-pear, seismic isolated device is decided as proper for cars' driving and for management of bridge since it decreases movement of upper structure, than elastic bearing, reducing size of elastic connect device, and it's been analyzed it is effective for improvement of fine view and economic efficiency reducing section of lower bridge structure. Finally, when design PSC I-shaped bridge bearing, for the proper structure and high-pier side, applying seismic isolated device through precise inner analysis is proper than applying equal elastic bearing.

• Food Science and Preservation
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• v.9 no.4
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• pp.375-379
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• 2002

This study has been carried out to investigate the food chemical composition in dried powder of main and lateral root of Acorus calamus L. Content of crude protein and crude fat in dried powder of main and lateral root were 12.76% and 9.84%, 7.43% and 3.42%, respectively. Total and reducing sugar of main and lateral root were 21.99％ and 7.67%, 24.12% and 0.65%. Major free sugars of root were sucrose, stachyose, raffinose, glucose and fructose. Sucrose of main and latent not were found to be the most predominant free sugars, contained 10.85 ％ and 1257%. Content of total amino acid were 427 mg% of main mot and 470 mg% of lateral root. Major total amino acids of root were arginine, glutamic acid, major free amino acids of main and lateral root were detected asparagine, arginine, glutamic acid and phenylalanine, respectively. Among the essential amino acids, the content of threonine was the highest (15.62 mg%) in main root and phenylalanine was the highest (12.67 mg%) in lateral root.

• Korean journal of applied entomology
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• v.3
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• pp.41-44
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• 1964

1. This experiment was planned to compare the effectiveness of Diazinon granular and gammadol dust with the low toxic organophosphorus insecticides applied on the water-surface for the control of the rice stem borer, Chilo suppressalis Walker, in the 2 nd generation and to determine the proper timing of those insecticidal applications at Suwon, Korea, in 1964. 2. The hatching larvae from the eggs were inoculated on the rice plants in pots and insecticides were applied on the water-surface of pots at a given day intervals. The dose of insecticides used per pot was calculated from the 120g. as a actual ingredient per 10 a. The number of living larvae was observed at the 20 days later from the inoculation (as shown in Table 1.). 3. As shown in Table 2 and 3, there was highly significance between the chemicals and L.S.D. was 24.22. The best effectiveness was Diazinon granular and 2nd was gamma-dol dust. The organophosphorus emulsion concentrations used in this experiment were less effective than two other insecticides. Although there were some suspicious results according to the day intervals inoculated, the order of effectiveness was Diazinon>gamma-dol>Sumithion>EM>EPN> Cidial as the total moan. 4, As shown in Table 2 and 3, there was no significance between the timing of insecticidal applications, but, m the whole, Diazinon granular was most effective at a given day intervals in this experiment and gamma-dol also was effective at the day Plot inoculated. The proper timing of EPN, EM, and Cidial seemed to be at e day plot inoculated and that of Sumithion at the day plot before inoculation.

• Spatial Information Research
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• v.17 no.3
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• pp.329-339
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• 2009

A historical and cultural map needs an overall reflection of the links based on time and space among the various composite factors, instead of requiring a simple collection of the respective relics in a particular region. The study of history, culture and living environment of river system area, a place that is known to as a cradle of civilization, will be able to undertake a role in the research and comparison with other cultural regions, reaching beyond the regional units until now and moreover investigation the international and intercontinental history of civilization. In this context, this research focuses on the establishment of a cultural information system for the public use and the insight to the regional identity and materialization of culture based on Korea's peculiar history and culture. Thus, the information system for Youngsan River area aims to create a form of electronic map that contains various cultural and historical information on river system area, which is a integrated information system based on Web GIS that is open to public use through the internet. The above mentioned system is a combined product from the basic research data on various fields of study, including archaeology, architecture, arts, ecological environment, history, folk customs, literature, and food, while it aims for not only its utilization in interdisciplinary studies but also creating new value as a public database. As a result, the expected effects due to the establishment of historical and cultural information system based on Web GIS of Youngsan River area are as follows: First, the study can contribute to verify a road map of the study on Youngsan River area. Second, it will take a role to stimulate the academical research on the dynamic structure and characteristics of the Youngsan River area. Third, we can also expect an effect of gaining a full foothold in providing an electronic academic source specialized for the study of the historical and cultural map.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.181-190
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• 2017

The purpose of This study was to find out the effects of the hotel advertising attitude and brand image on customers' purchase intention. For this study, a total of 306 questionnaires among collected data for customers who experience hotel service at five star hotels located in Seoul from April 1, 2015 to April 30, 2015 was to ensure a valid sample. As a result of the experiments which conducted by factor analysis and regression analysis, it shows positive significant effects in purchase intention of "feeling and persuade attitude factor" and "reputation and usefulness attitude factor", but it is not positively effected continual purchase intention in hotel customers. Also, it shows positive significant effects on hotel customers' purchase intention of "emotional brand image" and "physical brand image". From the study, it is expected to find efficient ways to activate purchase intention on hotel products through differentiated advertising and brand image. In addition, it should be considered that positive images building up emotional and physical characteristics in hotels for establishing consumer-brand relationship. From the study, it is expected to find efficient ways to activate purchase intention on hotel products through differentiated advertising and brand image.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.95-101
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• 2020

This study aims to investigate the current status of the operation system of the curriculum support extra-curricular program, focusing on the extra-curricular program operation system of other universities, and suggest the desirable operation system and performance management plan of the extra-curricular program in cultural education. To this end, the analysis of the extra-curricular program operation system of eight four-year universities in the Seoul metropolitan area was conducted on the existence of core competencies, computer systems and extra curricula program guides, credit-linked and mileage scholarship programs, and the analysis focused on the characteristics, merits and demerits of each university's operating system. It was also intended to propose the desirable operation system and performance management plan of the extra curricula program in liberal arts education, focusing on the operation system of the extra curricula program of E University and the corresponding performance management. Conclusion To operate the extra curricula program efficiently, the computer system and the extra curricula program guide, credit link and mileage scholarship system should be introduced. In addition, the analysis of the operation system of the curriculum support program of E University shows that E University operates systematically with the direction of operation of the core competency-based curriculum support extra-curricular program, and the performance management of the extra curricula program of E University is carried out through the EU-TQM System Integrated Management System.

• Journal of agricultural medicine and community health
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• v.29 no.2
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• pp.249-263
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• 2004

Objectives: The objectives of the present study were to establish the exposure monitoring method of chlorpyrifos and chlorothalonil application to pear and field red pepper by vehicle-mounted sprayer, hand-held sprayer and to assess the risk. Methods and Results: Chlorpyrifos met all of requirements of sampling and analysis method(U.S. EPA), but chlorothalonil met only dermal patch method. Potential dermal and inhalation exposure was evaluated in 42 farmers. Compared with the hand-held sprayer application, vehicle mounted sprayer demonstrated producing relatively lower dermal exposure levels with statistical significance. In dermal exposure during hand-held application, there is no significant difference between pear and red pepper. Conclusions: This results show that application method is the main factor of dermal exposure. There was no statistically significant difference between each group of respiratory exposure level. The margin of safety (MOS) was calculated to assess the risk of pesticide exposure. All Chlorpyrifos MOS values are lower than 0.2, which mean working conditions are unsafe. In order to protect farmers, big efforts to control exposure are needed.