• Journal of the Korean Institute of Gas
• /
• v.10 no.2 s.31
• /
• pp.33-39
• /
• 2006

For the safety design and operation of many gas process, it is necessary to know certain explosion limit, flash point, auto ignition temperature and minimum oxygen concentration of handling substances. Also it is necessary to know explosion limit at high temperature and pressure. For the safe handling of propane, explosion limit and autoignition temperature of combustion characteristics for propane were investigated. By using the literatures data, the lower and upper explosion limits of propane recommended 2.0 vol% and 10.0 vol%, respectively. Also autoignition temperatures of propane with ignition sources recommended $450^{\circ}C$ at the electrically heated cruicible fumace(the whole surface heating) and recommended about $960^{\circ}C$ at the local hot surface. The new equations for predicting the temperature and the pressure dependence of the explosion limits of propane are proposed. The values calculated by the proposed equations were a good agreement with the literature data.

• Journal of the Korean Institute of Gas
• /
• v.5 no.4 s.16
• /
• pp.70-78
• /
• 2001

In order to find out which equipment failures were mostly contributed to the rupture of a continuous stirred tank reactor, the sensitivity analysis was carried out. The uncertainty of likelihood of the rupture of reactor was studied by the uncertainty analysis. And the cost effectiveness analysis resulted in the recommendation of the exchange with a better reliable unit if you want to maintain the process efficiently from the view point of cost. The uncertainty analysis showed that the likelihood of catastrophic rupture of the reactor was distributed from $8.09{\times}10^{-04}$ to $5.50{\times}10^{-02}/year$. As a result of cost-effectiveness analysis, it was proposed to exchange the voting logic unit for a better safer system.

• The Journal of Pediatrics of Korean Medicine
• /
• v.18 no.1
• /
• pp.105-129
• /
• 2004

Methods: It was studied on the 47 kinds of oriental medical literature for fecal blood. Results: Fecal blood means bleeding with faces from anus and indicates all the three cases such as blooding before and after evacuation, evacuation of feces mixed with blood, and simple melena. The main causes are fire(火) and deficiency of spleen qi (脾氣虛). According to the color of fecal blood and the region of the bleeding, first, if the blood color is dark-red and blood discharges after emptying the bowels, it is called deposited poison into Jang(臟毒) or distant bleeding(遠血), and if the color of blood is clear and bowel emptying occurs after bleeding, it is bloody stool due to intestinal wind(腸風) or nearby bleeding(近血). For treating methods(治法). removing heat from the blood and stopping bleeding(淸熱凉血止血), removing dampness and stopping bleeding(淸熱除濕止血), invigorating Ki for promoting Hul-controJ(益氣攝血), warming the spleen and stomach to dispel cold and stopping bleeding(溫中散寒止血) etc are applied. As for the treating prescriptionl(治法), a Hwangtotang(黃土湯). Jeoksodudanggwitang(赤小豆當歸散). Gwihwasan(槐花散). Wipungtang(胃風湯). Hwangnyeonhwan modifying(黃連丸加減). Samultang modifying(四物湯加減). Paedoksan modifying(敗毒散加減) etc are used. As for acupuncture and moxibustion(鍼灸療法). if etiology(病因) is damp-heat(濕熱), acupuncture(刺鍼) at Janggang(長强); Charyo(BL 32); Sangeoheo(ST 37)(上巨虛); Seungsan(BL 57)(承山穴), and in case of deficiency of spleen Gi(脾氣虛), acupunture(刺鍼) with tonification(補法) at I Baek(EX-UE 2)(二白); Gwanwon(CC 4)(關元); Joksamni(ST 36)(足三里) Taebaek(SP 3)(太白); Hoeeum(CC 1)(會陰穴), or mxibuston(灸) at Baekoe(GC 2O)(百會); Myeongmun9GC (命門) or the point of opposite to umbilicus among spinal vertebrae(脊中對臍穴) are used. The external treatment(外治療法) was consisted of plastering umbilicus therapy(敷臍法) and enema therapy(灌腸法).

• Journal of the Korean Society of Combustion
• /
• v.19 no.2
• /
• pp.8-14
• /
• 2014

Experiments were conducted to clarify role of the outermost edge flame on low-strain-rate flame extinction in buoyancy-suppressed non-premixed methane flames diluted with He and $N_2$. The use of He curtain flow produced a microgravity level of $10^{-2}-10^{-3}g$ in $N_2$- and He-diluted non-premixed counterflow flame experiments. The critical He and $N_2$ mole fractions at extinction with a global strain rate were examined at various burner diameters (10, 20, and 25 mm). The results showed that the extinction curves differed appreciably with burner diameter. Before the turning point along the extinction curve, low-strain-rate flames were extinguished via shrinkage of the outermost edge flame with and without self-excitation. High-strain-rate flames were extinguished via a flame hole while the outermost edge flame was stationary. These characteristics could be identified by the behavior of the outermost edge flame. The results also showed that the outermost edge flame was not influenced by radiative heat loss but by convective heat addition and conductive heat losses to the ambient He curtain flow. The numerical results were discussed in detail. The self-excitation before the extinction of a low-strain-rate flame was well described by a dependency of the Strouhal number on global strain rate and normalized nozzle exit velocity.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.23 no.10
• /
• pp.115-120
• /
• 2009

In this parer, we design the artificial intelligent direction escape light control system to improve/complete the defects of the existing fire fighting system, and sketch an optimum escape guide algorithm for its implementation. It intends to minimize human casualties and injuries by calculating/predicting moving line of the optimum emergency escape, by means of interlocking the sensor and the reception group and analyzing the data of the combustion point and the smoke movement. The optimum escape algorithm is designed by FLOYD algorithm which calculates the shortest distance. It consists of the measuring method which calculates the shortest distance by using hazardous factors for each condition in danger which is judged by the sensor installed in each area.

• The Journal of the Korea Contents Association
• /
• v.18 no.9
• /
• pp.614-622
• /
• 2018

As multiple weapons are fired simultaneously in multi-target and multi-weapon environments, a possibility always exists in the collision occurred by the intersection between weapon trajectories. The collision between weapons not only hinders the rapid reaction but also causes the loss of the asset of weapons of friendly force to weaken the responsive power against the threat by an enemy. In this paper, we propose an intersection validation and interference elimination algorithm between weapon trajectories in multi-target and multi-weapon environments. The core points of our algorithm are to confirm the possible interference through the analysis on the intersections between weapon trajectories and to eliminate the mutual interference. To show the superiority of our algorithm, we implement the evaluation and verification of performances through the simulation and visualization of our algorithm. Our experimental results show that the proposed algorithm performs effectively the interference elimination regardless of the number of targets and weapon groups by showing that no cross point exists.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.6
• /
• pp.3944-3949
• /
• 2014

This paper provides a critical perspective in historic conservation with reference to Hanok (Korean Traditional Courtyard houses) built in central Taegu city, Korea. These Hanok houses began to emerge in the 1920s near the city castle during the Japanese occupation. The houses were shrewdly crafted into a small site in an urban context. Towards the end of 1980s, the demand for urban regeneration arose due to dilapidation of the timber structure and fire safety. Proposals were made to redevelop the areas, but they did not progress past this point. No attempts were made for conservation either and the urban fabric disintegrated continuously. The area is now largely unattended for conservation or redevelopment. This research intends to create an historic account of Hanok in an urban context for its enduring characteristics and historicity as charm and merit that deserve careful apprehension and conservation. This paper suggests that conservation not only serves to gentrify the cultural disruption of the early 20th century but also contributes towards urban regeneration.

• Journal of the Korean Professional Engineers Association
• /
• v.5 no.19
• /
• pp.3-16
• /
• 1972

1. Purposes and importances of the study. In gaining heating resources by combustion of briquette, which is the necessaries of every day's life, victims occur from poisonous affection of combustion gas (carbon mono-oxide) in every year and this gas attributable to increase death rate proportion to the high demand of briquette usage. It arise great problem ill point of national sanitation. Therefore, the study has a big aim to accomplish depressing CO gas or stimulating comlete combustion by both the methods of physical improvement of present combustion devices and chemical improvement by using V$_2$O$\sub$5/ catalyst to depress CO gas or fasten complete combustion Progress. Sucessful result of this study will not only to decrease the death rate but also to contribute fearless handling of briquette combustion so as to perform improving public Welfare. 2. Contents and scope of study. A. comparison of present and improved fuel hole device. B. Examination of effectness of improved elements. C. Effectness of miffed usage of catalyst. D. Comparison of Catalyst effectness. E. Examination of effectness of black slate containing V$_2$O$\sub$5/. 3. Results and recommendations of the study A. Absolute necessity of supplying secondary air by improved combustion device. B. Oxide Vanadium (V$_2$O$\sub$5/) has the greatest effectness to eliminate CO gas. C. Most effective catalyst of V$_2$O$\sub$5/ containing slate comes from "Samgoe" coal mine. D. By plastering catalyst on the cover plate of fire hole, it stimulate chemical reaction of re-combustion and preserving heat. E. Recommend to continute further precise study to practice with low-cost and handy devices to be applied the study results.

• Journal of Environmental Science International
• /
• v.24 no.9
• /
• pp.1101-1121
• /
• 2015

The seasonal variation of phytoplankton communities and its standing crops in accordance with environmental factors were investigated at Yeongrang-ho, Cheongcho-ho, Mae-ho and Hyang-ho which are located in the East coast of Korea during April to October 2011. High concentrations of T-N and T-P were observed in four lagoons due to the inflowing nutrients from farmlands and residential areas near lagoons. Nutrient salts mainly composed of nitrogen and phosphate caused the eutrophication of the lakes, leading to the robust growth of phytoplankton. During the period of investigation, 64 to 107 taxa of phytoplankton were observed in four lagoons. Diatoms were the most dominant species with high density. Non-point pollution source was estimated as the main cause of water pollution of lagoons. Trophic states of lagoons evaluated using the value of TSI and TSIKO indicated that all the investigated lagoons were in the eutrophication state.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2006.03a
• /
• pp.1100-1109
• /
• 2006

In this study, two different technologies which can measure temperature simultaneously at many points are introduced. One is to use a thermal sensor cable that is comprised of addressable thermal sensors connected in parallel within a single cable. The other is to use an optic fiber with Distributed Temperature Sensing (DTS) system. The difference between two technologies can be summarized as follows. A thermal sensor cable has a concept of 'point sensing' that can measure temperature at accurate position of a thermal sensor. So the accuracy and resolution of temperature measurement are up to the ability of the thermal sensor. Whereas optic fiber sensor has a concept of 'distributed sensing' because temperature is measured by ratio of Stokes and anti-Stokes component intensities of Raman backscatter that is generated when laser pulse travels along an optic fiber. It's resolution is determined by measuring distance, measuring time and spatial resolution. The purpose of this study is that application targets of two temperature measurement techniques are checked in technical and economical phases by examining the strength and weakness of them. Considering the functions and characteristics of two techniques, the thermal sensor cable will be suitable to apply to the assessment of groundwater flow, geothermal distribution and grouting efficiency within 300m distance. It is expected that the optic fiber sensor can be widely utilized at various fields (for example: pipe line inspection, tunnel fire detection, power line monitoring etc.) which need an information of temperature distribution over relatively long distance.