• Journal of the Korean Regional Science Association
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• v.40 no.2
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• pp.3-19
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• 2024

The purpose of this study is to analyze the impact of attracting a university campus on the local economies of small and medium-sized cities, focusing on changes in local commercial neighborhoods(such as the number of startups, closures, and stores counts). For this study, a Difference-in-Difference(DID) analysis was used to compare the period before and after the attraction of university campuses in four local small and medium-sized cities. These include the Yangsan Campus of Pusan National University, the Jincheon Campus of Woosuk University, the Taean Campus of Hanseo University, and the Dangjin Campus of Hoseo University. The comparison was based on the number of startups, closures, and store counts, using local data provided by the Ministry of the Interior and Safety. The main findings of the study are as follows. First, attracting a university campus has a positive impact on the number of startups, both spatially and temporally. The spatial factors for the number of closures and stores showed a decrease, while the interaction terms representing the period before and after attracting the university campus all indicated an increase. Second, the number of startups in cultural and food-related sectors increase, reflecting the new demand created by attracting the university campus. However, there was also an increase in the number of closures, indicating rapidly changing consumption trends among university students. Third, physical environmental factors such as the number of building floors, land use zoning, and officially assessed land prices have a significant impact on the number of startups, closures, and stores. This supports the assertion that attracting university campus have a positive impact on the revitalization of local commercial neighborhoods.

• Journal of the Korea Society of Computer and Information
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• v.29 no.3
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• pp.99-106
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• 2024

In this paper, we design and implement the HealthSchedule app, which records exercise data based on the GPS sensor embedded in smartphones. This app utilizes the smartphone's GPS sensor to collect real-time location information of the user and displays the movement path to the designated destination. It records the user's actual path using latitude and longitude coordinates. Users register exercise activities and destination points when scheduling, and initiate the exercise. When measuring the current location, a lime green departure marker is generated, and the movement path is displayed in blue, with the destination marker and a surrounding 25-meter radius circle shown in sky blue. Using the coordinates of the starting point or the previous location and the current GPS sensor-transmitted location coordinates, it measures the distance traveled, time taken, and calculates the speed. Furthermore, it accumulates measurement data to provide information on the total distance traveled, movement path, and overall average speed. Even when reaching the destination during exercise, the movement path continues to accumulate until the completion button is clicked. The completion button is activated when the user moves into the sky blue circular area with a radius of 25 meters, centered around the initially set destination. This means that the user must reach the designated destination, and if they wish to continue exercising without clicking the completion button, they can do so. Depending on the selected exercise type, the app displays the calories burned, aiming to increase user engagement and a sense of accomplishment.

• Korean Chemical Engineering Research
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• v.62 no.3
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• pp.233-237
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• 2024

This study is about the fabrication of a flexible electrode based on PAN-based carbon fibers tow using organic/inorganic nanocomposite and its application of non-enzymatic sensor. The organic/inorganic nanocomposite was composed of the conductive polymer polyaniline (PANI) and the metal oxide CuO. And glucose was used as the target of the electrochemical sensor. Commercialized CFTs were pretreated through heat treatment for desizing and electrochemical oxidation for activation. This nanocomposite was sequentially synthesized on the pretreated CFT surface using electrochemical polymerization and electrochemical deposition. Finally, the CFT/PANI/CuO NPs electrode was obtained. The electrochemical properties and sensing performance of the CFT/PANI/CuO NPs electrode were analyzed using chronoamperometry (CA), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The sensitivity of the CFT/PANI/CuO NPs electrode was about 8.352 mA/mM (in a linear range of 0.445~6.674 mM) and 3.369 mA/mM (in a linear range of 6.674~50 mM), respectively. So, the CFT/PANI/CuO NPs electrode exhibited the enhanced sensing performances due to unique properties such as small peak potential separation, low electron transfer resistance, and large specific surface area.

• The Journal of Bigdata
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• v.8 no.2
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• pp.1-13
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• 2023

Current analysis of air passengers mainly relies on statistical methods, but there are limitations in analyzing detailed aspects such as travel routes, number of regional passengers and airport access times. However, with the advancement of big data technology and revised three data acts, big data-based transportation analysis has become more active. Mobile communication data, which can precisely track the location of mobile phone terminals, can serve as valuable analytical data for transportation analysis. In this paper, we propose a air passenger Origin/Destination (O/D) extraction algorithm based on mobile communication data that overcomes the limitations of existing air transportation user analysis methods. The algorithm involves setting airport signal detection zones at each airport and extracting air passenger based on their base station connection history within these zones. By analyzing the base station connection data along the passenger's origin-destination paths, we estimate the entire travel route. For this paper, we extracted O/D information for both domestic and international air passengers at all domestic airports from January 2019 to December 2020. To compensate for errors caused by mobile communication service provider market shares, we applied a adjustment to correct the travel volume at a nationwide citizen level. Furthermore correlation analysis was performed on O/D data and aviation statistics data for air traffic users based on mobile communication data to verify the extracted data. Through this, there is a difference in the total amount (4.1 for domestic and 4.6 for international), but the correlation is high at 0.99, which is judged to be useful. The proposed algorithm in this paper enables a comprehensive and detailed analysis of air transportation users' travel behavior, regional/age group ratios, and can be utilized in various fields such as formulating airport-related policies and conducting regional market analysis.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.349-359
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• 1997

Background : The signal pathways and their precise roles for acute respiratory distress syndrome caused by endotoxin (ETX) has not been established. Since there has been several in vitro experiments suggesting that activation of protein kinase C (PKC) pathway may be responsible for endotoxin-induced inflammatory reaction, we performed in vivo experiments in the rats with the hypothesis that PKC-inhibition can effectively prevent endotoxin-induced acute lung injury. Methods : We studied the role of PKC in ETX-induced ALI using PKC inhibitor (staurosporine, STP) in the rat Specific pathogen free male Sprague-Dawley weighted from 165 to 270g were used for the study. Animals were divided into the normal control (NC)-, vehicle control (VC)-, ETX-, PMA (phorbolmyristateacetate)-, STP+PMA-, and STP+ETX-group. PMA (50mg/kg) or ETX (7mg/kg) was instilled through polyethylen catheter after aseptic tracheostomy with and without STP (0.2mg/kg)-pretreatment STP was injected via tail vein 30min before intratracheal injection (IT) of PMA or ETX. Bronchoalveolar lavage (BAL) was done 3-or 6-hrs after IT of PMA or ETX respectively, to measure protein concentration, total and differential cell counts. Results : The results were as follows. The protein concentrations in BALF in the PMA- and ETX-group were very higher than that of VC-group (p<0.001). When animals were pretreated with STP, the %reduction of the protein concentration in BALF was $64.8{\pm}8.5$ and $30.4{\pm}2.5%$ in the STP+PMA- and STP+ETX-group, respectively (p = 0.028). There was no difference in the total cell counts between the PMA-and VC-group (p = 0.26). However the ETX-group showed markedly increased total cell counts as compared to the VC- (p = 0.003) and PMA-group (p = 0.0027), respectively. The total cell counts in BALF were not changed after pretreatment with STP compared to the PMA- (p = 0.22) and ETX-group (p = 0.46). The percentage of PMN, but not alveolar macrophage, was significantly elevated in the PMA-, and ETX-group. Especially in the ETX-group, the percentage of PMN was 17 times higher than that of PMA (p < 0.001). The differential cell counts was not different between the PMA and STP+PMA On the contrary the STP+ETX-group showed decreased percentage of PMN (p = 0.016). There was no significant relationship between the protein concentration and the total or differential cell counts in each group. Conclusion : Pretreatment with PKC-inhibitor (staurosporine) partially but significantly inhibited ETX-induced ALI.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.1
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• pp.35-45
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• 2020

This study focused on the park as a space to support the behavior of urban citizens in modern society. Modern city parks are not spaces that play a specific role but are used by many people, so their function and meaning may change depending on the user's behavior. In addition, current online data may determine the selection of parks to visit or the usage of parks. Therefore, this study analyzed the change of behavior in Yeouido Park, Yeouido Hangang Park, and Yangjae Citizen's Forest from 2000 to 2018 by utilizing a time series analysis. The analysis method used Big Data techniques such as text mining and social network analysis. The summary of the study is as follows. The usage behavior of Yeouido Park has changed over time to "Ride" (Dynamic Behavior) for the first period (I), "Take" (Information Communication Service Behavior) for the second period (II), "See" (Communicative Behavior) for the third period (III), and "Eat" (Energy Source Behavior) for the fourth period (IV). In the case of Yangjae Citizens' Forest, the usage behavior has changed over time to "Walk" (Dynamic Behavior) for the first, second, and third periods (I), (II), (III) and "Play" (Dynamic Behavior) for the fourth period (IV). Looking at the factors affecting behavior, Yeouido Park was had various factors related to sports, leisure, culture, art, and spare time compared to Yangjae Citizens' Forest. The differences in Yangjae Citizens' Forest that affected its main usage behavior were various elements of natural resources. Second, the behavior of the target areas was found to be focused on certain main behaviors over time and played a role in selecting or limiting future behaviors. These results indicate that the space and facilities of the target areas had not been utilized evenly, as various behaviors have not occurred, however, a certain main behavior has appeared in the target areas. This study has great significance in that it analyzes the usage of urban parks using Big Data techniques, and determined that urban parks are transformed into play spaces where consumption progressed beyond the role of rest and walking. The behavior occurring in modern urban parks is changing in quantity and content. Therefore, through various types of discussions based on the results of the behavior collected through Big Data, we can better understand how citizens are using city parks. This study found that the behavior associated with static behavior in both parks had a great impact on other behaviors.

• Journal of Periodontal and Implant Science
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• v.29 no.2
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• pp.311-326
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• 1999

This study was investigated to observe the effect of Treponema denticola(TDC) and Treponema lecithinolyticum(TLC) on cultured human periodontal ligament cells. Several experiments were performed including MTT test for the inhibition effect of cell proliferation, LDH test for the cytotoxicity , gelatin zymography for the gelatinase activation and observation of cell morphology change using the phase-contrast microscopy. The results were as follows. 1. The effect of concentration on cell proliferation with time showed an inhibitory effect at high concentration $(150{\mu}g/well)$ for TLC and at low concentration( $9.4{\mu}gwell$ ) for TDC. 2. The effect of time on cell proliferation with concentration showed an inhibitory effect at $150{\mu}g/well$ on 2-day incubation for TLC and at $9.4{\mu}g/well$ on 2-day incubation for TDC. 3. The effect of heat-treated TDC and TLC on the inhibition of cell proliferation showed the difference in the heat-treated group compared to the non-heat treated group for TDC, whereas no difference was found for TLC. 4. The morphological changes which were observed from the phase-contrast microscopy showed the difference in the test group compared to the control group. The loss of spindle-like appearance, cell-to-cell detachment and inhibition of cell proliferation were observed. 5. There was no difference of the cytotoxicity effect between the test group and the control group in the LDH test. 6. The active form of progelatinase A with molecular weight 72kDa was activated in both TDC and TLC on the gelatin zymography. Regarding to the above results, TDC and TLC have an effect on periodontal ligament cells by playing an inhibitory role in cell proliferation and appears to activate progelatinase A which degrades type IV collagen.

• Sleep Medicine and Psychophysiology
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• v.7 no.2
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• pp.96-101
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• 2000

Objectives: Through comparing sleep variables and autonomic activities among three shifts in shift workers, the authors intended to clarify which shift is most tolerable and to identify the characteristics of their psychological and physical problems. This study is also expected to help shift workers to adapt themselves to their work more effectively. Methods: Fifty one shift workers took part in this study. They were working in a rapidly rotating system in which they worked for 3 days in one shift with one day off between each shift. Based on a sleep diary, sleep latency (SL), sleep period time (SPT), and number of wake after sleep onset (NWASO) were estimated and compared among the three shifts. In assessing sleepiness, Epworth sleepiness scale (ESS) and visual analogue scale (VAS) were used. To evaluate mood states among the three shifts, profile of mood states (POMS) was administered. Heart rate variability (HRV), and the level of adrenaline and noradrenaline were measured to assess autonomic activities. HRV included low frequency power (LF), high frequency power (HF), and LF/HF. Results: SPT was significantly lengthened during the evening shift and SL was shortened during the night shift. The workers showed a drop in alertness at wake-up during morning shift and a drop in alertness at work during night shift. During night shift the subjects complained of physical fatigue and cognitive decline. Comparison of HRV showed that parasympathetic activity was most prominent during the evening shift. Secretion of adrenaline and noradrenaline decreased during the evening shift, though statistically not significant. Conclusion: We found that the evening shift was most tolerable among the three shifts. It is recommended that morning light exposure be done during the morning shift and nocturnal light exposure during the night shift.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.186-192
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• 1997

Increased activities of phase 2 enzymes including quinone reductase(QR) have been reported to be associated with protection of animals from neoplastic, mutagenic, and other toxic effects of many carcinogens. In previous study, we found that methanol extract of roasted and defatted perilla meal induced the activity of quinone reductase, an anticarcinogenic marker enzyme, in murine hepalc1c7 cells. Current study showed that unroasted perilla had a limited QR-inducing activity, suggesting that roasting cause the generation of active component(s). Thus we hypothesized that QR inducer in perilla might be covalently linked to sugar moiety and released during roasting process. Methanol extract of defatted raw perilla was subject to acid treatment in order to hydrolyze the potential sugar moiety. Prolonged hydrolysis of methanol extract of defatted raw perilla at $98{\sim}100^{\circ}C$ increased the ability to induce cytosolic QR activity of hepalclc7 cells. Furthermore roasting at 180 and $200^{\circ}C$ resulted in significant induction of QR activity. The result strongly support the idea that QR inducer(s) is present in bound form in raw perilla and released during roasting. Cellular QR activity was induced proportionately with the increase of concentration of methanol extract of roasted perilla. The induction of QR by defatted perilla was also examined in the cytosols of liver, small intestine, stomach, lung and kidney of male ICR mice. Induction patterns showed specificity with respect to target tissue and roasting of perilla. Unroasted perilla meal (defatted) significantly induced QR in liver and lung, while roasted perilla meal induced QR in liver and stomach. The observation that raw perilla showed similar QR induction patterns to roasted perilla is consistent with our proposal that QR inducer(s) is present in bound form and released by physical and chemical treatments as digestive or microbial enzymes could release the inducers from inactive glycoside forms in gastrointestinal tract of mice. In conclusion, perilla could exert protective effect against chemically induced carcinogenesis by inducing phase 2 enzymes in biological systems regardless of chemical and physical process such as roasting.

• Clinical and Experimental Pediatrics
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• v.46 no.7
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• pp.695-701
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• 2003

Purpose : It had been suggested that pain arising from deep somatic body regions influences neural activity within periaqueductal gray(PAG) of midbrain via distinct spinal pathways. Aspirin is one of the popular non-steroidal anti-inflammatory drugs used in the management of pain. Fos expression was used as a marker for neuronal activity throughout central neurons following painful peripheral stimulation. This study was prepared to investigate changes of c-Fos immunoreactivity in midbrain by deep pain and effects of aspirin. Methods : Male Sprague-Dawley rats were injected with 0.1 mL of 5% formalin in the plantar muscle of the right hindpaw. For experimental group II, aspirin was injected intravenously before injection of formalin. An aspirin-untreated group was utilized as group I. Rats were sacrificed at 0.5, 1, 2, 6 and 24 hours after formalin injection. Rat's brains were removed and sliced in rat brain matrix. Brain slices were coronally sectioned at interaural 1.00-1.36 mm. Serial sections were immunohistochemically reacted with polyclonal c-Fos antibody. The numbers of c-Fos protein immunoreactive neurons in ventrolateral periaqueductal gray(VLPAG) and dorsomedial periaqueductal gray(DMPAG) were counted and analyzed statistically with Mann-Whitney U tests. Results : Higher numbers of c-Fos protein immunoreactive neurons were found in VLPAG. In both VLPAG and DMPAG of formalin-treated group, the numbers of c-Fos protein immunoreactive neurons were significantly higher at all time points than the formalin-untreated group, which peaked at two hours. The numbers of c-Fos immunoreactive neuron of the aspirin-treated group were less compared to the aspirin-untreated group at each time point. Conclusion : These results provide some basic knowledge in understanding the mechanism of formalin-induced deep somatic pain and the effects of aspirin.