• Particle and aerosol research
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• v.6 no.1
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• pp.9-20
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• 2010

This study examined the concentration level of the major air pollutants in public transportation. The study was conducted between February 2009 and March 2008 at Suwon-Yeosu line in Korea. $PM_{10}$ concentration level was $100{\mu}g/m^3$ on average. The $PM_{2.5}$ to PM10 ratio in transport is 0.37, which was lower than the results published by other researches. The result also demonstrated that outdoor $PM_{10}$ concentration was about 56~60% level compared to that of the cabin. $CO_2$ concentration level in the cabin was 1,359ppm, which does not exceed 2,000ppm, which is the guideline concentration level according to the Ministry of Environment. $CO_2$ concentration level in the cabin was $CO_2=23.4{\times}N+460.2$, and about 23.4ppm in $CO_2$ concentration level increased every time one passenger was added on. The experiment conducted on the train demonstrated that the average $PM_{10}$ concentration level was $100{\mu}g/m^3$ in case of the reference cabin while average $PM_{10}$ concentration level of the modified vehicle was $68{\mu}g/m^3$. Likewise, effect of the particle reduction device for the reduction of $PM_{10}$ concentration level was approximately 21%. Meanwhile there was almost no difference in the concentration level between reference and modified cabin in case of $PM_{2.5}$. Using zeolite as an adsorbent was made to reduce the $CO_2$ concentration level in the cabin. Number of passengers was factored in, to calculate the effect of the adsorption device, which demonstrated that about 36% of $CO_2$ concentration level was reduced in the modified cabin effect of the $CO_2$ reduction device. This research analyzed the current status concerning the quality of air in the public transportation and technologies were developed that reduces major air pollutants.

• Analytical Science and Technology
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• v.13 no.4
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• pp.453-465
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• 2000

Polycyclic aromatic hydrocarbons (PAHs) were produced by thermoreaction (incompletely combustion) of organic compounds such as fuel, gasoline, diesel etc, and were known the strong carcinogenic compounds. In our country, a study for health risk assessment of PAHs in air were needed according to rapidly increasing of motor vehicle and progressing to industrial country. In this study, concentrations of PAHs in 263 air samples of fourteen sites-Seoul, Pusan, etc-according to four times sampling for one year are measured by GC/MSD for basic research for health risk assessment. As the result, 14 PAHs are detected in all samples and annual average concentration of total PAHs was $28.72ng/m^3$ and highest average concentration of total PARs was $47.76ng/m^3$ in winter season. The concentrations of total PAHs are proportioned to amount of extracted organic material (EOM). The average concentration of total PAHs in EOM was 0.28%.

• Korean Journal of Veterinary Research
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• v.39 no.5
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• pp.878-895
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• 1999

Ischemic preconditioing (IPC), i.e., a preliminary brief episode of ischemia and reperfusion, has been shown to reduce the cell damage induced by long ischemia and reperfusion. Superoxide radical which is produced during reperfusion after ischemia was recognized as a factor of the ischemic injury and it is dismutated into $H_2O_2$ and $O_2$ by two types of intracellular superoxide dismutase (SOD), Cu,Zn-SOD in cytoplasm and Mn-SOD in mitochondria. Recently oxygen free radicals are suggested to induce the apoptosis, however mechanism of the reduced apoptosis by ischemic preconditioing was unknown, while many studies performed in mammalian heart indicated that ATP-sensitive $K^+$ ($K_{APT}$) channel activation related with the protective effects. The aim of present study is to investigate 1) whether IP upregulate the Cu,Zn-SOD and Mn-SOD activities, and 2) whether ischemic preconditioning decreases apoptosis via $K_{APT}$ channel activation in timely reperfused skeletal muscle after long ishemia. The experimental animals, Sprague-Dawley rats weighing 250~300g, were divided into 8 groups; 1) control group, 2) ischemic preconditioning only groups, 3) pinacidil, a $K_{APT}$ channel opener, treatment only groups, 4) glibenclamide, a $K_{APT}$ channel blocker, treatment only groups, 5) ischemia groups, 6) ischemia after IPC groups, 7) ischemia and pinacidil treatment groups, and 8) IP and ischemia after glibenclamide pretreatment groups. Animals of the control group were administered with the vehicle (DMSO) alone. Pinacidil (1mg/kg) was administered intravenously 5 minutes after initiation of ischemia, and glibenclamide (0.5mg/kg) was injected intravenously 20 minutes before IPC. In rats that were ischemic preconditioned, the left common iliac artery was occluded for 5 minutes followed by 5 minutes of reperfusion by three times using vascular clamp. Ischemia was done by occlusion of the same artery for 4 hours. The specimens of left rectus femoris muscle were obtained immediately (0 hour), 12 hours, 24 hours after drug administrations, IP or ischemia and reperfusion. The immunoreactivities of SOD and its alterations were observed by use of sheep antihuman Cu,Zn-SOD and Mn-SOD antibodies on the $10{\mu}m$ cryosections. The incidencies of apoptosis were observed by TUNEL methods with in situ apoptosis detection kit on $6{\mu}m$ paraffine section. The results obtained were as follows : 1. After IPC, immunoreactivities of Cu,Zn-SOD mainly in the small-sized fibers were increased by 24 hours, that of Mn-SOD at 0 hour and 24 hours. 2. No significant changes in immunoreactivities of SOD was observed in the pinacidil and in the glibenclamide treatment only groups, and in the ischemia only groups. 3. The immunoreactivities of the Cu,Zn-SOD were increased in the ischemia after IPC groups and the ischemia and pinacidil treatment groups. 4. The immunoreactivities of the Cu,Zn-SOD in the IPC and ischemia after glibenclamide pretreatment groups were not increased except for the 12 hours reperfusion group. But, Mn-SOD immunoreactivities were increased in the 0 hours, 12 hours and 24 hours after reperfusion. 5. In the control group, the IPC only groups, and the pinacidil treatment only groups, negative or trace apoptotic reactions were observed, but the positive apoptotic reaction occured in the glibenclamide treatment groups. 6. Moderate or many number of apoptosis were revealed in the ischemia groups, and also the IPC and ischemia after glibenclamide pretreatment group except for 12 hours and 24 hours after reperfusion. However, the incidence of apoptosis was decreased in the ischemia after IPC groups and in the ischemia and pinacidil treatment groups. 7. There is a coincidence between the increase of Cu,Zn-SOD immunoreactivities and the decrease of apoptosis in the presence of ischemia and reperfusion. These results suggest that the protective effects of ishemic preconditioing may related to the SOD activation, and the ischemic preconditioning decreases the apoptosis partially via $K_{APT}$ channel activation in timely reperfused rat skeletal muscle. It is also suggested that inhibition of apoptosis by IPC may related with the SOD activation.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.1
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• pp.92-99
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• 2012

Many wildlife habitats have been destroyed and fragmented during the rapid industrialization and urbanization process in Korea. It is essential to connect these fragmented habitats to reduce road-kill of many types of endangered urban wildlife. The site selection for wildlife passages must take into account the behavior of the wildlife species for safe crossing utilizing many artificial barriers in urban areas. This study attempted to identify potential wildlife passage sites for the endangered and protected leopard cats of Gangseo Ecological Park in Seoul, Korea. A space syntax analysis, an analytical technique to objectively evaluate the spatial configurations related to passage selection, found that the integration value represents the accessibility and connectivity of spaces. In this paper, this means that the bigger the integration value, the more frequently the leopard cat passes through. The leopard cats were captured and radio-tracked for 72 hours once a month from March to June of 2009. The ArcGIS and Animal Movement of Hawth Tools were used to analyze the home range and movement paths, and Axwoman 4.0 was used to analyze space syntax. The daily average movement distance was $2.099{\pm}1.08km$. During the survey period, the leopard cats crossed over an urban expressway more than 20 times, running the risk of road-kill. The range of global integration values was 0.458~1.834, while that of the local integration was 0.210~6.061. Five sites that met across the leopard cats' movement routes and roads were selected to measure the local and global integrate values. Among these sites, the higher the integration value, the higher the road-kill possibility. Thus, two of five sites with high global and local integration values were suggested as potential wildlife passage sites for the leopard cats. Now, three tunnel passages are under construction at the suggested sites for which local integration value was highest (LI=4.369). Further studies are scheduled to verify these potential sites as suitable wildlife passages.

• Journal of Life Science
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• v.25 no.11
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• pp.1214-1222
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• 2015

The purpose of this study was to determine the effect of Pueraria lobate-root based combination supplementation containing Rehmannia glutinosa and exercise on histone modification in ovariectomized rat hindlimb skeletal muscle. Sixty rats were fed with high fat diet and randomly assigned into the following groups for 8 weeks: 1)HSV; High fat+Sedentary+Vehicle, 2)HSP; High fat+Sedentary+PR, 3)HSH; High fat+Sedentary+Estradiol, 4)HEV; High fat+Ex+Vehicle, 5)HEP; High fat+Ex+PR, 6)HEH; High fat+Ex+Estradiol. Exercise consisted of low intensity treadmill exercise(1-4th wk:15 m/min for 30 min, 5-8th wk: 18 m/min for 40 min, 5 times/week). The result of this study showed that exercise and Pueraria and Rehmannia glutinosa intake suppressed weight gain. Furthermore, exercise and Pueraria and Rehmannia glutinosa intake increased muscle mass. This study observed H3K9 acetylation and demethylation in plantaris muscle in exercised group, but no difference in soleus muscle. To test whether the decrease in HDAC4, HDAC5 and G9a mRNA levels after exercise and Pueraria/Rehmannia glutinosa intake, HDAC4, HDAC5 and G9a mRNA levels were determined by real-time PCR. Only exercise induced HDAC5 and G9a mRNA reduction in plantaris muscle, but not in soleus muscle. In conclusion, these data demonstrates that exercise and Pueraria/Rehmannia glutinosa intake effect on body compositions. These changes are regulated by epigenetic modifications, such as histone acetylation and methylation. Future studies should focus on gene-specific epigenetics and other epigenetic mechanism for Pueraria/Rehmannia glutinosa intake.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.6
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• pp.915-936
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• 2017

In this study, current status of Korean hazard mitigation guideline for tunnel operation is summarized. It shows that requirement for CCTV installation has been gradually stricted and needs for tunnel incident detection system in conjunction with the CCTV in tunnels have been highly increased. Despite of this, it is noticed that mathematical algorithm based incident detection system, which are commonly applied in current tunnel operation, show very low detectable rates by less than 50%. The putative major reasons seem to be (1) very weak intensity of illumination (2) dust in tunnel (3) low installation height of CCTV to about 3.5 m, etc. Therefore, an attempt in this study is made to develop an deep-learning based tunnel incident detection system, which is relatively insensitive to very poor visibility conditions. Its theoretical background is given and validating investigation are undertaken focused on the moving vehicles and person out of vehicle in tunnel, which are the official major objects to be detected. Two scenarios are set up: (1) training and prediction in the same tunnel (2) training in a tunnel and prediction in the other tunnel. From the both cases, targeted object detection in prediction mode are achieved to detectable rate to higher than 80% in case of similar time period between training and prediction but it shows a bit low detectable rate to 40% when the prediction times are far from the training time without further training taking place. However, it is believed that the AI based system would be enhanced in its predictability automatically as further training are followed with accumulated CCTV BigData without any revision or calibration of the incident detection system.

• Geophysics and Geophysical Exploration
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• v.8 no.4
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• pp.270-279
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• 2005

Under the research project supported by Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT), we have conducted the development of GPR systems for landmine detection. Until 2005, we have finished development of two prototype GPR systems, namely ALIS (Advanced Landmine Imaging System) and SAR-GPR (Synthetic Aperture Radar-Ground Penetrating Radar). ALIS is a novel landmine detection sensor system combined with a metal detector and GPR. This is a hand-held equipment, which has a sensor position tracking system, and can visualize the sensor output in real time. In order to achieve the sensor tracking system, ALIS needs only one CCD camera attached on the sensor handle. The CCD image is superimposed with the GPR and metal detector signal, and the detection and identification of buried targets is quite easy and reliable. Field evaluation test of ALIS was conducted in December 2004 in Afghanistan, and we demonstrated that it can detect buried antipersonnel landmines, and can also discriminate metal fragments from landmines. SAR-GPR (Synthetic Aperture Radar-Ground Penetrating Radar) is a machine mounted sensor system composed of B GPR and a metal detector. The GPR employs an array antenna for advanced signal processing for better subsurface imaging. SAR-GPR combined with synthetic aperture radar algorithm, can suppress clutter and can image buried objects in strongly inhomogeneous material. SAR-GPR is a stepped frequency radar system, whose RF component is a newly developed compact vector network analyzers. The size of the system is 30cm x 30cm x 30 cm, composed from six Vivaldi antennas and three vector network analyzers. The weight of the system is 17 kg, and it can be mounted on a robotic arm on a small unmanned vehicle. The field test of this system was carried out in March 2005 in Japan.

• Electrical & Electronic Materials
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• v.12 no.7
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• pp.7-11
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• 1999

Fully sealed field emission display in size of 4.5 inch has been fabricated using single-wall carbon nanotubes-organic vehicle com-posite. The fabricated display were fully scalable at low temperature below 415$^{\circ}C$ and CNTs were vertically aligned using paste squeeze and surface rubbing techniques. The turn-on fields of 1V/${\mu}{\textrm}{m}$ and field emis-sion current of 1.5mA at 3V/${\mu}{\textrm}{m}$ (J=90${\mu}{\textrm}{m}$/$\textrm{cm}^2$)were observed. Brightness of 1800cd/$m^2$ at 3.7V/${\mu}{\textrm}{m}$ was observed on the entire area of 4.5-inch panel from the green phosphor-ITO glass. The fluctuation of the current was found to be about 7% over a 4.5-inch cath-ode area. This reliable result enables us to produce large area full-color flat panel dis-play in the near future. Carbon nanotubes (CNTs) have attracted much attention because of their unique elec-trical properties and their potential applica-tions [1, 2]. Large aspect ratio of CNTs together with high chemical stability. ther-mal conductivity, and high mechanical strength are advantageous for applications to the field emitter [3]. Several results have been reported on the field emissions from multi-walled nanotubes (MWNTs) and single-walled nanotubes (SWNTs) grown from arc discharge [4, 5]. De Heer et al. have reported the field emission from nan-otubes aligned by the suspension-filtering method. This approach is too difficult to be fully adopted in integration process. Recently, there have been efforts to make applications to field emission devices using nanotubes. Saito et al. demonstrated a car-bon nanotube-based lamp, which was oper-ated at high voltage (10KV) [8]. Aproto-type diode structure was tested by the size of 100mm $\times$ 10mm in vacuum chamber [9]. the difficulties arise from the arrangement of vertically aligned nanotubes after the growth. Recently vertically aligned carbon nanotubes have been synthesized using plasma-enhanced chemical vapor deposition(CVD) [6, 7]. Yet, control of a large area synthesis is still not easily accessible with such approaches. Here we report integra-tion processes of fully sealed 4.5-inch CNT-field emission displays (FEDs). Low turn-on voltage with high brightness, and stabili-ty clearly demonstrate the potential applica-bility of carbon nanotubes to full color dis-plays in near future. For flat panel display in a large area, car-bon nanotubes-based field emitters were fabricated by using nanotubes-organic vehi-cles. The purified SWNTs, which were syn-thesized by dc arc discharge, were dispersed in iso propyl alcohol, and then mixed with on organic binder. The paste of well-dis-persed carbon nanotubes was squeezed onto the metal-patterned sodalime glass throuhg the metal mesh of 20${\mu}{\textrm}{m}$ in size and subse-quently heat-treated in order to remove the organic binder. The insulating spacers in thickness of 200${\mu}{\textrm}{m}$ are inserted between the lower and upper glasses. The Y\ulcornerO\ulcornerS:Eu, ZnS:Cu, Al, and ZnS:Ag, Cl, phosphors are electrically deposited on the upper glass for red, green, and blue colors, respectively. The typical sizes of each phosphor are 2~3 micron. The assembled structure was sealed in an atmosphere of highly purified Ar gas by means of a glass frit. The display plate was evacuated down to the pressure level of 1$\times$10\ulcorner Torr. Three non-evaporable getters of Ti-Zr-V-Fe were activated during the final heat-exhausting procedure. Finally, the active area of 4.5-inch panel with fully sealed carbon nanotubes was pro-duced. Emission currents were character-ized by the DC-mode and pulse-modulating mode at the voltage up to 800 volts. The brightness of field emission was measured by the Luminance calorimeter (BM-7, Topcon).

• The Korean Journal of Air & Space Law and Policy
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• v.9
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• pp.85-143
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• 1997

The main purpose of the investigation of an accident caused by aircraft is to be prevented the sudden and casual accidents caused by wilful misconduct and fault from pilots, air traffic controllers, hijack, trouble of engine and machinery of aircraft, turbulence during the bad weather, collision between birds and aircraft, near miss flight by aircrafts etc. It is not the purpose of this activity to apportion blame or liability for offender of aircraft accidents. Accidents to aircraft, especially those involving the general public and their property, are a matter of great concern to the aviation community. The system of international regulation exists to improve safety and minimize, as far as possible, the risk of accidents but when they do occur there is a web of systems and procedures to investigate and respond to them. I would like to trace the general line of regulation from an international source in the Chicago Convention of 1944. Article 26 of the Convention lays down the basic principle for the investigation of the aircraft accident. Where there has been an accident to an aircraft of a contracting state which occurs in the territory of another contracting state and which involves death or serious injury or indicates serious technical defect in the aircraft or air navigation facilities, the state in which the accident occurs must institute an inquiry into the circumstances of the accident. That inquiry will be in accordance, in so far as its law permits, with the procedure which may be recommended from time to time by the International Civil Aviation Organization ICAO). There are very general provisions but they state two essential principles: first, in certain circumstances there must be an investigation, and second, who is to be responsible for undertaking that investigation. The latter is an important point to establish otherwise there could be at least two states claiming jurisdiction on the inquiry. The Chicago Convention also provides that the state where the aircraft is registered is to be given the opportunity to appoint observers to be present at the inquiry and the state holding the inquiry must communicate the report and findings in the matter to that other state. It is worth noting that the Chicago Convention (Article 25) also makes provision for assisting aircraft in distress. Each contracting state undertakes to provide such measures of assistance to aircraft in distress in its territory as it may find practicable and to permit (subject to control by its own authorities) the owner of the aircraft or authorities of the state in which the aircraft is registered, to provide such measures of assistance as may be necessitated by circumstances. Significantly, the undertaking can only be given by contracting state but the duty to provide assistance is not limited to aircraft registered in another contracting state, but presumably any aircraft in distress in the territory of the contracting state. Finally, the Convention envisages further regulations (normally to be produced under the auspices of ICAO). In this case the Convention provides that each contracting state, when undertaking a search for missing aircraft, will collaborate in co-ordinated measures which may be recommended from time to time pursuant to the Convention. Since 1944 further international regulations relating to safety and investigation of accidents have been made, both pursuant to Chicago Convention and, in particular, through the vehicle of the ICAO which has, for example, set up an accident and reporting system. By requiring the reporting of certain accidents and incidents it is building up an information service for the benefit of member states. However, Chicago Convention provides that each contracting state undertakes collaborate in securing the highest practicable degree of uniformity in regulations, standards, procedures and organization in relation to aircraft, personnel, airways and auxiliary services in all matters in which such uniformity will facilitate and improve air navigation. To this end, ICAO is to adopt and amend from time to time, as may be necessary, international standards and recommended practices and procedures dealing with, among other things, aircraft in distress and investigation of accidents. Standards and Recommended Practices for Aircraft Accident Injuries were first adopted by the ICAO Council on 11 April 1951 pursuant to Article 37 of the Chicago Convention on International Civil Aviation and were designated as Annex 13 to the Convention. The Standards Recommended Practices were based on Recommendations of the Accident Investigation Division at its first Session in February 1946 which were further developed at the Second Session of the Division in February 1947. The 2nd Edition (1966), 3rd Edition, (1973), 4th Edition (1976), 5th Edition (1979), 6th Edition (1981), 7th Edition (1988), 8th Edition (1992) of the Annex 13 (Aircraft Accident and Incident Investigation) of the Chicago Convention was amended eight times by the ICAO Council since 1966. Annex 13 sets out in detail the international standards and recommended practices to be adopted by contracting states in dealing with a serious accident to an aircraft of a contracting state occurring in the territory of another contracting state, known as the state of occurrence. It provides, principally, that the state in which the aircraft is registered is to be given the opportunity to appoint an accredited representative to be present at the inquiry conducted by the state in which the serious aircraft accident occurs. Article 26 of the Chicago Convention does not indicate what the accredited representative is to do but Annex 13 amplifies his rights and duties. In particular, the accredited representative participates in the inquiry by visiting the scene of the accident, examining the wreckage, questioning witnesses, having full access to all relevant evidence, receiving copies of all pertinent documents and making submissions in respect of the various elements of the inquiry. The main shortcomings of the present system for aircraft accident investigation are that some contracting sates are not applying Annex 13 within its express terms, although they are contracting states. Further, and much more important in practice, there are many countries which apply the letter of Annex 13 in such a way as to sterilise its spirit. This appears to be due to a number of causes often found in combination. Firstly, the requirements of the local law and of the local procedures are interpreted and applied so as preclude a more efficient investigation under Annex 13 in favour of a legalistic and sterile interpretation of its terms. Sometimes this results from a distrust of the motives of persons and bodies wishing to participate or from commercial or related to matters of liability and bodies. These may be political, commercial or related to matters of liability and insurance. Secondly, there is said to be a conscious desire to conduct the investigation in some contracting states in such a way as to absolve from any possibility of blame the authorities or nationals, whether manufacturers, operators or air traffic controllers, of the country in which the inquiry is held. The EEC has also had an input into accidents and investigations. In particular, a directive was issued in December 1980 encouraging the uniformity of standards within the EEC by means of joint co-operation of accident investigation. The sharing of and assisting with technical facilities and information was considered an important means of achieving these goals. It has since been proposed that a European accident investigation committee should be set up by the EEC (Council Directive 80/1266 of 1 December 1980). After I would like to introduce the summary of the legislation examples and system for aircraft accidents investigation of the United States, the United Kingdom, Canada, Germany, The Netherlands, Sweden, Swiss, New Zealand and Japan, and I am going to mention the present system, regulations and aviation act for the aircraft accident investigation in Korea. Furthermore I would like to point out the shortcomings of the present system and regulations and aviation act for the aircraft accident investigation and then I will suggest my personal opinion on the new and dramatic innovation on the system for aircraft accident investigation in Korea. I propose that it is necessary and desirable for us to make a new legislation or to revise the existing aviation act in order to establish the standing and independent Committee of Aircraft Accident Investigation under the Korean Government.