• Korean Journal of Environmental Biology
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• v.23 no.3 s.59
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• pp.221-227
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• 2005

The effects of light and $CO_2$ on the electrophysiological characteristics of guard cells in the intact leaf and isolated epidermis have been investigated. Fast hyperpolarization of guard cell apoplastic PD in the intact leaf was recorded reaching up to around 7 mV and 20 mV in response to light and $CO_2$. Whenever the experiments were attempted with isolated epidermis, there was no response to light and $CO_2$. In order to determine the influence of the mesophyll cells, the apoplastic PD of guard cells in isolated epidermis was measured in the presence of the mesophyll supernatant or the control medium. The apoplastic PD in isolated epidermis was hyperpolarized to -7mV, changing from -22mV to -29mV at 40 min. But, when isolated epidermis was incubated with the supernatant from mesophyll cells incubated in the light, the apoplastic PD in isolated epidermis was hyperpolarized to -19 mV, changing from -22 mV to -40.5 mV. $CO_2$ also caused a change of 0.1 to 0.3 pH unit in the intact leaf. However, this change was absent in isolated epidermis. A vibrating probe was used to detect the change in electrical currents at the surface of excised intact leaves and isolated epidermis. The reading of excised intact leaves in the dark was $0.5\muA\;cm^{-2},$ remaining steady until illuminated. Light increased the current on the surface of excised leaves to about $0.8\muA\;cm^{-2},$. However, light had no effect in the current on the surface of isolated epidermis. Apoplastic pH changes across the stomatal complex in response to light and dark were measured both in the intact leaves and isolated epidermis over the same time period using pH micro-electrodes. The guard cell wall of intact leaf was acidified to 2.5 pH unit, falling from pH 7.5 to pH 5.0 in the first 10 min. in the light. At the same time the guard cell wall pH of isolated epidermis fell from pH 7.5 to pH 7.0 at 10 min. The guard cell wall pH of isolated epidermis incubated in the mesophyll supernatant fell from pH 7.6 to pH 6.7 at 10 min. Likewise, It could be imagined that an electrical signal, chemicals and hormones propagated from the mesophyll in response to light and $CO_2$ could control a fast stomatal response.

• Korean journal of food and cookery science
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• v.25 no.6
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• pp.671-676
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• 2009

In order to develop and propagate the low sodium kimchi for preventing high sodium related diseases, the salinity, pH and acidity of cabbage(Bachu) kimchi sampled from home located in 6 big cities(Pusan, Daegoo, Kyungjoo, Daegoo, Jeonjoo, Daejeon, and Seoul) and commercial 6 manufacturers(A~F) distributed in markets were monitored and analyzed in the current study. Salinity was significantly (p<0.05) higher in homemade($3.03%{\pm}0.60$: 1.79~4.40) kimchi than in commercial($2.38%{\pm}0.60$:1.04~2.87) kimchi. Also, salinity was significantly(p<0.05) higher in Pusan($3.45{\pm}0.60%$) kimchi than in Kyungjoo($3.11{\pm}0.39$), Daegoo($3.19{\pm}0.42$), Jeonjoo($2.98{\pm}0.32$), Daejeon($3.00{\pm}0.38$) and Seoul ($2.52{\pm}0.46%$) kimchi. However, there was no significant difference(p<0.05) of salinity in 6 kinds of commercial kimchi. Related to this result, pH of kimchi from homemade and commercial was $4.40{\pm}0.29$(3.72~6.03) and $5.45{\pm}0.76$ (4.23~6.35), acidity of kimchi from homemade and commercial were $0.99{\pm}0.30%$(0.28~2.17) and $0.45{\pm}023$(0.17~0.93), respectively. Thus, the current study provides evidence that we may need to manufacture the low sodium kimchi because all homemade kimchi, especially Pusan and Daegoo kimchi and commercial brand kimchi contained over 2% salinity.

• Journal of Navigation and Port Research
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• v.34 no.3
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• pp.175-180
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• 2010

In the almost application parts, GNSS being used the primary navigation system on world-widely. However, some of nations attempt or deliberate to enhance current Loran system, as a backup to satellite navigation system because of the vulnerability to the disturbance signal. Loran interests in supplemental navigation system by the development and enhancement, which is called eLoran, and that consists of advancement of receiver and transmitter and of differential Loran in order to increase the accuracy of current Loran-C. A significant factor limiting the ranging accuracy of the eLoran signal is the ASF in the TOAs observed by the receiver. The ASF is mostly due to the fact that the ground-wave signal is likely to propagate over paths of varying conductivity and topography. This paper presents comparison results between the predicted ASF and the measured ASF in a southern east region of Korea. For predicting ASF, the Monteath model is used. Actual ASF is measured from the legacy Loran signal transmitted Pohang station in the GRI 9930 chain. The test results showed the repeatability of the measured ASF and the consistent characteristics between the predicted and the measured ASF values.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.3
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• pp.517-526
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• 2008

A one-chip DC-DC converter circuit for OLED(Organic Light-Emitting Diode) display module of automotive clusters is newly proposed. OLED panel driving voltage circuit, which is a charge-pump type, has improved characteristics in miniaturization, low cost and EMI(Electro-Magnetic Interference) compared with DC-DC converter of PWM(Pulse Width Modulator) type. By using bulk-potential biasing circuit, charge loss due to parasitic PNP BJT formed in charge pumping, is prevented. In addition, the current dissipation in start-up circuit of band-gap reference voltage generator is reduced by 42% and the layout area of ring oscillator is reduced by using a logic voltage VLP in ring oscillator circuit using VDD supply voltage. The driving current of VDD, OLED driving voltage, is over 40mA, which is required in OLED panels. The test chip is being manufactured using $0.25{\mu}m$ high-voltage process and the layout area is $477{\mu}m{\times}653{\mu}m$.

• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.237-246
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• 2021

The similarity of hourly PM₁₀ and PM_2.5 concentration profiles of the atmospheric monitoring stations in Gyeonggi-do was evaluated through the multilateral analysis between stations. The existing category for most stations in the regions shows relatively low Pearson correlation values of 0.68 and 0.7 for PM₁₀ and PM_2.5 on average respectively, and some monitoring stations revealed high relationships over 0.8 to other regions. Since the current regions are mainly categorized by cluster analysis based on the number of occurrence of high concentration events and geological factors, it is necessary to reclassify them by concentration characteristics for precise fine dust management. In accordance, multi-dimensional scaling being able to visualize could categorize the regions based on regional emission contribution rate and hourly fine dust concentration. As a result of the current analysis, PM₁₀ and PM_2.5 could be reclassified into five regions and fourregions, respectively.

• 한국체육학회지인문사회과학편
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• v.51 no.3
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• pp.427-435
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• 2012

The purpose of this review study is to examine current status of dietary supplement use to enhance athletic performance capacity in elite athletes based upon anti-doping education, sports type, athletic performance capacity, gender, and age. Several previous review studies have focused on the biochemistry characteristics and intake incidence of dietary supplements and those studies have not showed enough evidence of the reason why elite athletes usually take dietary supplements. Anti-doping education may increase the incidence of dietary supplement use in elite athletes because of increasing expertise of dietary supplements. It would be expected that increased incidence of long-term dietary supplement use may induce positive effects on the body having potential effects on athletic performance capacity, although a trace of nutrients may not directly effect on the outcome of the game. Moreover, it seems that the difference of dietary supplement use based upon gender and age may come from sports type and the difference of dietary supplement intake reason may come from health and body condition maintenance rather than athletic performance capacity when considering dietary supplement use items based upon intake reasons. Most elite athletes consume at least over 2 dietary supplement items in a long period of time rather than 1 dietary supplement item in a short period of time; however, the scientific evidence of dietary supplement use seems to be insufficient. Therefore, further experimental approach studies concerning dietary supplement effects would be needed.

• Journal of Service Research and Studies
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• v.11 no.2
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• pp.1-19
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• 2021

This study was conducted to derive a model of a sustainable politics and administration system that will enhance human happiness. A new long-term sustainable development model has been established based on the experience of the politics and administration system over the past thousands of years. Currently, the democratic political system and the bureaucratic administrative system dominate, but they are facing many problems. In this study, we analyzed the politics and administration system experienced by human society, and derived a model of a politics and administration system that is ideal for the present and future societies and is sustainable in the long term. The necessary condition should be a model that can solve the problems of the current politics and administration system. It must be a model that is faithful to the characteristics and essence of modern society. And as a sufficient condition to ensure long-term sustainability, it must be based on the common principles of human society. After analyzing the problems of the current system and analyzing the conditions required for the new system, the axioms that are the basis of the politics and administration system were presented. Based on the axioms, the structure and operation model of a new politics and administration system were derived. The derived model was named as a servicism politics and administration system. It is a dynamic model in which two opposing opponents recognize each other's contradictions and balance them dialectically in the space-time dimension.

• The Korean Journal of Archival Studies
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• no.79
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• pp.271-303
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• 2024

In our country, which has a strong presidential system, the power and responsibilities of the president are truly enormous. He is the head of state and diplomatic representative, and at the same time exercises authority over all areas of the country, including the legislature, judiciary, and constitutional institutions, along with his responsibilities as head of the executive branch. Considering these aspects, it can be said that presidential records created during the president's rule have a high level of national and historical significance and value compared to other public records. Considering these importance of presidential records, the Presidential Records Management Act was enacted in 2007 to establish an institutional mechanism to systematically manage presidential records. However, the current institutional basis for appraisal of presidential records is very weak. In this regard, there is a need to begin discussions on the appraisal of presidential records in earnest. Considering the national importance and symbolism of presidential records, it is necessary to establish a new direction for appraisal of presidential records that is different from general public records. Accordingly, in this paper, as part of reestablishing Korea's presidential records appraisal system, this article analyzed the status and problems of the current presidential records appraisal system and presented directions needed to find future improvement measures. To this end, as a premise for discussing the importance and value of presidential records, it examined the powers and responsibilities of the presidency as defined in our country's Constitution.Next, we looked at the appraisal system and method for presidential records that are currently in operation, and then analyzed the problems that emerged here in connection with the characteristics of presidential records. Based on this, it presented five perspectives on issues that need to be discussed publicly in the records management community in order to reestablish Korea's presidential records appraisal system in the future.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.3
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• pp.109-129
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• 2011

Since the introduction of local autonomy system, various specific theories and practical approaches for private commission system have been common concerns and interests of the fields practicing social welfare. In the discussion about private consignment system of social welfare facility and organization, both of private section and government have shown different opinions from various aspects such as related regulation, consignment procedure, proper period and consignment condition. According to the discussion about the consignment system of social welfare facility, the purpose of this study is as follows. The first purpose is to suggest the current status of private consignment of social welfare facility and the characteristic and issue of consignment procedure by considering domestic & overseas literatures about the characteristic of private consignment system. The second purpose is to find out the general characteristics and current statuses of consignment process and system of social welfare facilities (organizations) located in Gyeonggi-do area. The third purpose is to draw the current status and general problem of field consignment system and suggest the practical alternative plan and improvement method of private consignment system of social welfare facility in the future. The result of researching private consignment process by head and manager of social welfare facility (organization), private consignment agreement and its conclusion process and current consignment system improvement method revealed that the number of reconsigned (over 1~3 times) facilities was more than that of initially consigned facilities and senior welfare facility and general social welfare center were most frequent in private consignment organization. In addition, as an improvement method of current private consignment process, the consideration on each organization and standard was required for new consignment and reconsignment and the problem of fairness and objectiveness was indicated when deliberation committee was organized in private consignment process. Besides them, it was found that consignment period shall be adjusted on the basis of facility type and business characteristic and the problems such as worker's succession, worker's transfer and service disconnection were suggested when consignment organization was changed. For conclusion and suggestion, the study suggested the establishment of common standard about private consignment, alternative plan of private consignment process issue and improvement method of consignment period issue.

• Journal of Korea Water Resources Association
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• v.41 no.12
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• pp.1219-1230
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• 2008

Stream inflows induced by flood runoffs have a higher density than the ambient reservoir water because of a lower water temperature and elevated suspended sediment(SS) concentration. As the propagation of density currents that formed by density difference between inflow and ambient water affects reservoir water quality and ecosystem, an understanding of reservoir density current is essential for an optimization of filed monitoring, analysis and forecast of SS and nutrient transport, and their proper management and control. This study was aimed to quantify the characteristics of inflow density current including plunge depth($d_p$) and distance($X_p$), separation depth($d_s$), interflow thickness($h_i$), arrival time to dam($t_a$), reduction ratio(${\beta}$) of SS contained stream inflow for different flood magnitude in Daecheong Reservoir with a validated two-dimensional(2D) numerical model. 10 different flood scenarios corresponding to inflow densimetric Froude number($Fr_i$) range from 0.920 to 9.205 were set up based on the hydrograph obtained from June 13 to July 3, 2004. A fully developed stratification condition was assumed as an initial water temperature profile. Higher $Fr_i$(inertia-to-buoyancy ratio) resulted in a greater $d_p,\;X_p,\;d_s,\;h_i$, and faster propagation of interflow, while the effect of reservoir geometry on these characteristics was significant. The Hebbert equation that estimates $d_p$ assuming steady-state flow condition with triangular cross section substantially over-estimated the $d_p$ because it does not consider the spatial variation of reservoir geometry and water surface changes during flood events. The ${\beta}$ values between inflow and dam sites were decreased as $Fr_i$ increased, but reversed after $Fr_i$>9.0 because of turbulent mixing effect. The results provides a practical and effective prediction measures for reservoir operators to first capture the behavior of turbidity inflow.