• Fire Science and Engineering
• /
• v.15 no.1
• /
• pp.23-33
• /
• 2001

The utility tunnels are the important facility as a mainstay of country because of the latest communication developments. However, the utilities tunnel is difficult to deal with in case of a fire accident. When a cable burns, the black smoke containing poisonous gas will be reduced. This black smoke goes into the tunnel, and makes it difficult to extinguish the fire. Therefore, when there was a fire in the utility tunnel, the central nerves of the country had been paralyzed, such as property damage, communication interruption, in addition to inconvenience for people. This paper is based on the fire occurred in the past, and reenacting the fire by making the real utilities tunnel model. The aim of this paper is the scientific analysis of the character image of the fire, and the verification of each fire protection system whether it works well after process of setting up a fire protection system in the utilities tunnel at a constant temperature. The fire experiment was equipped with the linear heat detector, the fire door, the connection water spray system and the ventilation system in the utilities tunnel. Fixed portion of an electric power supply cable was coated with a fire retardant coating, and a heating tube was covered with a fireproof. The result showed that the highest temperature was $932^{\circ}c$ and the linear heat detector was working at the constant temperature, and it pointed at the place of the fire on the receiving board, and Fixed portion of the electric power supply cable coated with the fire retardant coating did not work as the fireproof. The heating tube was covered with the fireproof about 30 minutes.

• Applied Chemistry for Engineering
• /
• v.10 no.4
• /
• pp.557-562
• /
• 1999

The reaction properties of Pd. Pd-Ce and Pd-La catalysts supported on ${\gamma}-Al_2O_3$ were investigated in the oxidation reaction of methane($CH_4$) exhausted from the compressed natural gas vehicle in a U-tube flow reactor with gas hourly space velocity of $72,000h^{-1}$. The catalysts were characterized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), BET surface area and hydrogen chemisorption. Pd catalyst prepared by $Pd(NO_3)_2$ as a palladium precursor and calcined at $600^{\circ}C$ showed the highest activity for a methane oxidation. Catalytic activity of calcined $Pd/{\gamma}-Al_2O_3$ in which most of palladium was converted into palladium oxide species was higher than that of reduced $Pd/{\gamma}-Al_2O_3$ in which most of palladium existed in palladium metal by XRD. As increasing the number of reaction cycles in the wide range of redox, the catalytic activity of $Pd/{\gamma}-Al_2O_3$ was decreased and the highly active window became narrower. Lanthanum oxide promoted Pd catalyst, $Pd/La/{\gamma}-Al_2O_3$ showed enhanced thermal stability compared with $Pd/{\gamma}-Al_2O_3$ even after aging at $1000^{\circ}C$, which was ascribed to the role of La as a promoter to suppress the sintering of palladium metal and ${\gamma}-Al_2O_3$ support. Almost all of methane was removed by the reaction with NO at the redox ratio of 1.2 in case of oxygen excluded steam, but that activity was significantly decreased in the steam containing oxygen.

• Korean Security Journal
• /
• no.19
• /
• pp.105-138
• /
• 2009

This study's purpose is to present the improvement of effectiveness of security activity for international conference among Several Countries which can be held hereafter. On the basis of security activity problems originating in APEC that had been held in Busan in 2005. I made up questions three times to on the members of the police, military, fire figher and national intelligence service who had experienced in Busan APEC and recognition of possible problem and possibility of improvement on each item of questions was analyzed by Delphi Method. Also interviews with 4 security experts selected from each security agency were conducted to present improvement in each part of problem. The results obtained from the face to face interview with four experts of security-enforcement agency about the role and importance of site activity stage for international conference among several countries are as followings ; First, the system that experienced security-enforcement agents can be selected for the next national security event is needed, by data-basing the security-enforcement agents who were experienced in security event as man power management. Second, the middle-term plan for the introduction of high-tech equipment and joint inspection with relevant security agents are needed for the efficient explosive technical detection. Third, high-tech security equipment could be introduced through the international high-tech security equipment exhibition. Fourth, an anti-terrorism plan should be measured by sharing information through the cooperation with domestic and international intelligence agency. Fifth, public relations should be measured systematically by organization rather than agents' individual public relations. Sixth, political consideration to secure integrative coordination with other agency is needed for security activity, through normal cooperation with fire fighting related agency such as an electric, gas, elevator company. Seventh, a definite press guideline is needed for a convenient news coverage and safety during security event.

• Journal of Chest Surgery
• /
• v.31 no.7
• /
• pp.643-649
• /
• 1998

Background: For the patient with chronic obstructive pulmonary disease requiring long-term oxygen therapy, oxygen concentrator machines are already widely available for use in home. In this study, we used mongrel dogs as test subjects to compare the functional efficiency and safety of the oxygen concentrator developed by our own research team with those of the imported FORLIFE(TM) machine made by AIRSEP Corp. Method and method: To test mechanical reliability, the concentrations of oxygen delivered were measured after 4 hours of continuous operation. Sixteen mongrel dogs were divided into two equal groups. Mongrel dogs in group A were given oxygen using the imported oxygen concentrator, and those in group B using the machine developed. 5 l/min of oxygen were given, after which vital signs were analyzed, arterial blood gases measured, and blood chemistry tests carried out. Results: After 4 hours of continuous operation, the imported model performed better, giving 98${\pm}$3% oxygen, compared to our model, which gave 91${\pm}$1%. In the animal experiments, oxygen concentrations were measured at the inlet of face mask 1, 2, 3, and 4 hours after continuous administration, and there was no statistically significant difference(repeated measures of analysis of variance p=0.70) between the values of 70.6${\pm}$2.5%, 67.1${\pm}$2.9%, 68.2${\pm}$2.6%, and 64.9${\pm}$3.9% that were measured from group A, and the values of 65.1${\pm}$4.8%, 65.2${\pm}$3.6%, 68.7${\pm}$4.3%, and 66.0${\pm}$5.0% measured from group B. Before oxygen administration, and at 1, 2, 3, and 4 hours after oxygen administration, arterial blood partial pressure of oxygen 87.2${\pm}$2.5 mmHg, 347.4${\pm}$29.3 mmHg, 353.4${\pm}$21.2 mmHg, 343.0${\pm}$28.8 mmHg, and 321.6${\pm}$24.4 mmHg, respectively, were read from group A, which were not statistically different (p=0.24) to the values of 102.5${\pm}$9.6 mmHg, 300.3${\pm}$17.1 mmHg, 321.6${\pm}$23.7 mmHg, 303.4${\pm}$27.4 mmHg, and 273.5${\pm}$25.9 mmHg read from group B. Nonetheless, the arterial blood partial pressure of oxygen values appear to be somewhat higher in dogs that were given oxygen using the imported oxygen concentrator. Conclusions: From these results the prototype oxygen concentrator developed appears to function relatively satisfactorily compared to the imported, established model, but may be criticized for the excessive noise generated and poor long-term endurance or consistency, which need improvement.

• Journal of the Korean Electrochemical Society
• /
• v.6 no.1
• /
• pp.59-64
• /
• 2003

We fabricated mixed ionic-electronic conducting membranes, $CH_4\;Using\;{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$, by solid state reaction method for solid oxide fuel cell. The membranes consisted of single perovskite phase and exhibited high relative density, $>95\%$. We coated $La_{0.6}Sr_{0.4}CoO_{3-\delta}$ layer using screen printing method in order to improve surface reactivity of the $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$. As a result, the oxygen permeation flux of the coated $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$ showed higher value, $0.5ml/min{\cdot}cm^2\;at\;950^{\circ}C$ than the uncoated one. Higher oxygen permeation was observed in the porously coated Lao $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$membranes with larger grain sizes. Syngas, $CO+H_2$, was successfully obtained from methane gas, $CH_4$, using the $La_{0.6}Sr_{0.4}CoO_{3-\delta}$ coated $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$, with over $40\%\;of\;CH_4$ conversion and syngas yield. $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$ membrane was stable even when it was exposed to the reducing environment, methane, for 600 hrs at $950^{\circ}C$.

• Journal of Korean Society of Environmental Engineers
• /
• v.30 no.12
• /
• pp.1287-1293
• /
• 2008

In this study, a blend of 2-amino-2-methyl-1-propanol (AMP) and ammonia (NH$_3$) was used to achieve high absorption rates for carbon dioxide (CO$_2$) as suggested at several literatures. The absorption rates of aqueous AMP and blended AMP+NH$_3$ solutions with CO$_2$ and nitrogen dioxide (NO$_2$) were measured using a stirred-cell reactor at 303 K. The effect of the added NH$_3$ to enhance absorption characteristics of AMP was studied. The performances were evaluated under various operating conditions. The absorption rates increased following the increase of the concentration of NH$_3$. The absorption rate of NH$_3$ blended into 30 wt.% AMP solution with NO$_2$ at 303 K was 12.6$\sim$32.6% higher than that of aqueous AMP solution without NH3. Also, the addition of 3 wt.% NH$_3$ to 30 wt.% AMP increased 48.2$\sim$41.6% values for the reactions with CO$_2$ and NO$_2$ at 303 K. Therefore, it clearly shows that the reaction rate of AMP with CO$_2$ and NO$_2$ can be increased by the addition of NH$_3$.

• Economic and Environmental Geology
• /
• v.40 no.5
• /
• pp.517-535
• /
• 2007

Two distinctive Mesozoic hydrothermal systems occurred in South Korea: the Jurassic/Early Cretaceous(ca. $200{\sim}130$ Ma) deep-level ones during the Daebo orogeny and the Late Cretaceous/Tertiary(ca. $110{\sim}45$ Ma) shallow hydrothermal ones during the Bulgugsa event. The Mesozoic hydrothermal system and the metallic mineralization in the Korean Peninsula document a close spatial and temporal relationship with syn- to post-tectonic magmatism. The calculated ${\delta}^{18}O_{H2O}$ values of the ore-forming fluids from the Mesozoic metallic mineral deposits show limited range for the Jurassic ones but variable range for the Late Cretaceous ones. The orogenic mineral deposits were formed at relatively high temperatures and deep-crustal levels. The mineralizing fluids that were responsible for the formation of theses deposits are characterized by the reasonably homogeneous and similar ranges of ${\delta}^{18}O_{H2O}$ values. This implies that the ore-forming fluids were principally derived from spatially associated Jurassic granitoids and related pegmatite. On the contrary, the Late Cretaceous ferroalloy, base-metal and precious-metal deposits in the Taebaeksan, Okcheon and Gyeongsang basins occurred as vein, replacement, breccia-pipe, porphyry-style and skarn deposits. Diverse mineralization styles represent a spatial and temporal distinction between the proximal environment of subvolcanic activity and the distal to transitional condition derived from volcanic environments. The Cu(-Au) or Fe-Mo-W deposits are proximal to a magmatic source, whereas the polymetallic or the precious-metal deposits are more distal to transitional. On the basis of the overall ${\delta}^{18}O_{H2O}$ values of various ore deposits in these areas, it can be briefed that the ore fluids show very extensive oxygen isotope exchange with country rocks, though the ${\delta}D_{H2O}$ values are relatively homogeneous and similarly restricted.

• Journal of Animal Science and Technology
• /
• v.53 no.2
• /
• pp.155-160
• /
• 2011

Present experiment was carried out to determine maintenance energy requirements for growing Hanwoo steers. Six Hanwoo steers (BW = $180.6{\pm}3.1$ kg) were used in two 3 ${\times}$ 3 latin square design with three different energy intake levels; TDN 1.70 kg (Low), 2.05 kg (Medium), 2.80 kg (High), respectively, based on the Korean Feeding Standards. Each period lasted 18 days including a 14-day adaptation and a 4-day measuring period. The steers were in the head hood chamber system (one cattle per chamber) during each measuring time to measure heat and methane production for 1 day. Dry matter intake was 2,058, 3,256 and 3,881 g/day for Low, Medium and High TDN, respectively. Increase in energy intake did not affect digestibilities of dry matter, crude protein, crude fiber, crude fat, NDF, ADF and nitrogen-free extract. Gross energy intake averaged 180.21, 292.74 and 337.15 kcal/$BW^{0.75}$ for Low, Medium and High TDN, respectively. Energy loss was 28.7% in feces and 2.1% in urine of gross energy intake. Further, energy loss from methane produced during rumen fermentation was 6~8.3%, while body heat loss averaged 34~60%. Intercept of regression equation between ME intake and retained energy indicated that the energy requirement was 109.84 kcal ME/$BW^{0.75}$.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.17 no.1
• /
• pp.15-24
• /
• 2015

$CH_4$ is a trace gas and one of the key greenhouse gases, which requires continuous and systematic monitoring. The application of eddy covariance technique for $CH_4$ flux measurement requires a fast-response, laser-based spectroscopy. The eddy covariance measurements have been used to monitor $CO_2$ fluxes and their data processing procedures have been standardized and well documented. However, such processes for $CH_4$ fluxes are still lacking. In this note, we report the first measurement of $CH_4$ flux in a rice paddy by employing the eddy covariance technique with a recently commercialized wavelength modulation spectroscopy. $CH_4$ fluxes were measured for five consecutive days before and after the rice transplanting at the Gimje flux monitoring site in 2012. The commercially available $EddyPro^{TM}$ program was used to process these data, following the KoFlux protocol for data-processing. In this process, we quantified and documented the effects of three key corrections: (1) frequency response correction, (2) air density correction, and (3) spectroscopic correction. The effects of these corrections were different between daytime and nighttime, and their magnitudes were greater with larger $CH_4$ fluxes. Overall, the magnitude of $CH_4$ flux increased on average by 20-25% after the corrections. The National Center for AgroMeteorology (www.ncam.kr) will soon release an updated KoFlux program to public users, which includes the spectroscopic correction and the gap-filling of $CH_4$ flux.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1979.05a
• /
• pp.6.2-6
• /
• 1979

Foreing bodies of the esophagus and tracheobronchus are likely to occur whenever a child places an inedible object in the mouth and are common in the older age group particularily in edentulous individuals or preexisting disease. Our department had already reported the statistical survey at first in 1954, successively in 1962, 1963 and 1968, respectively according to the age, sex, variety of foreign bodies, location and duration of the lodgement. Now, we have experienced the new 186 cases during the consecutive 5 year period from January 1973 to December 1977 and reported as a 5th report comparing with previous report. The results were as follows. 1. In the incidence of foreign bodies, coins were the most common and pointed metal, disc, bony fragment were followed in order in the esophagus while the peanut and corn were common in the air passage. 2) 79 cases (56.4%) were males and 61 cases (43.6%) were females in the esophagus, which was not a significant difference to note. But in the air passage, males accounted for 33 cases (71.7%) compared to 13 cases (28.3%) of females. 3) In the aspect of age incidence, child 10 years or under accounted for almost all cases in the esophagus as well as in the air passage. 4) In the location of foreign bodies in the esophagus, the first narrowing was the most common, while in the air passage right bronchus had a high incidence but the difference of incidence between right bronchus and left bronchus was not remarkable. 5) The duration of lodgement was 24 hours or less in more than half of the all cases. 6) In the aspect of kind of coin, 10 won coins accounted for majority of the cases (67.0%) but the incidence of 100 won coins were tend to increase gradually in these years.