• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6B
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• pp.565-575
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• 2011

The purpose of this study was to quantitatively evaluate the expression of both multi-metric qualitative habitat evaluation index (QHEI) and biological integrity index (IBI) for artificial structures eco-artificial fish reef (EAFR) for fishes asylum and habitat. Especially, both experimental evaluation and biological verification were performed in Water and Environmental Center's outdoor test-bed of Korea Institute of Construction Technology located in Andong-city, Gyeongsangbuk-do. The experimental conditions reflecting the situation of domestic river include the flow rate (e.g., $0.0{\sim}1.5m\;s^{-1}$), the width (e.g., 1.0~3.0 m), the depth (e.g., 0.05~0.70 m), and variable bed materials. Both QHEI and IBI were monitored for 8 months from May to December 2010. Whereas QHEI values were highest at experimental points of the E~F with an average of 83.1, those were lowest at B~C with an average of 78.1. However, QHEI values inside EAFR were more than 98.9, regardelss of space and time, and indicated more than the highest good of the state (Good) in the habitat. Overally, IBI values showed similar trend with QHEI, but were 44.2 in the winter dry season, compared to 32.8 of QHEI values. IBI values Also, IBI values inside EAFR were greater than those at the experimental channel by 5.7 to 11.4% and 18.7 to 34.8% in flow and stagnant conditions, respectively, indicating that EAFR can secure asylum and habitat for fish during the dry season. For comprehensive aquatic ecosystem assessment, the experimental channel showed generally fair conditions (Fair~Good), whereas EAFR showed good conditions (Good), suggesting that EAFR can be applied to aquatic ecosystem restoration and improvement.

• Journal of the Korean Geosynthetics Society
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• v.12 no.4
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• pp.67-76
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• 2013

Landfill require special care due to the dangers of nearby surface water and underground water pollution caused by leakage of leachate. The leachate does not leak due to the installation of the geomembrane but sharp wastes or landfill equipment can damage the geomembrane and therefore a means of protecting the geomembrane is required. In Korea, in accordance with the waste control act being modified in 1999, protecting the geosynthetics liner on top of the slope of landfill and installing a drainage layer to fluently drain leachate became mandatory, and technologies are being researched to both protect the geomembrane and quickly drain leachate simultaneously. Therefore, this research has its purpose in studying the drainage functions of leachate and protection functions of the geomembrane in order to examine the application possibilities of Geo-Multicell-Composite (GMC) as a Leachate Collection Removal and Protection System (LCRPs) at the slope on top of the geomembrane of landfill by observing methods of inserting filler with high-quality water permeability at the drainage net. GMC's horizontal permeability coefficient is $8.0{\times}10^{-4}m^2/s$ to legal standards satisfeid. Also crash gravel used as filler respected by vertical permeability is 5.0 cm/s, embroidering puncture strength 140.2 kgf. A result of storm drain using artificial rain in GMC model facility, maxinum flow rate of 1,120 L/hr even spray without surface runoff was about 92~97% penetration. Further study, instead of crash gravel used as a filler, such as using recycled aggregate utilization increases and the resulting construction cost is expected to savings.

• Journal of agricultural medicine and community health
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• v.21 no.1
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• pp.61-73
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• 1996

This study conducted to determine the attitude on environment pollution by Pohang city citizens. 1,059 Pohang city citizens in the age group 20 and over were chosen and surveyed by officials's interview at Up, Myun and Dong during the period 6 September to 20 September 1995. The issue problems to be solved in Pohang city were traffic control 47.3%, environment pollution 22.7%, cultural institutions 11.6%, water service 9.9%, education system 5.1% and community security 2.1%. The 55.1% of subjects responded that responsibility for environment pollution is every citizens duty. The trash from houses were 'garbage'(48.1%), 'waste of life'(21.8%), 'reuse trash'(15.6%) and 'one use thing'(14.5%) in order. The 66.9% of subjects responded that the trash's standard envelopes can be easily tear and its texture is not good. The respondents sometimes or often had experienced foreign bodies, sediment in the water service supply. The 45.9% of the respondents use natural water as drinking water, and the water service supply(26.7%), underground water(17.0%) and buying water(9.3%) were followed. Pertaining to the air pollution(by percent) was pollution of the steel industry complex 78.0%, combustive gas 16.6% and construction dust 1.7%. The respondents at southern district complained of respiratory tract by air pollution and the respondents at northern district complained of the visual disturbance and the offensive odor(P<0.05). Water pollution problem is factory's wastewater 56.2%, home wastewater 36.4% and livestock's wastewater 5.6% in order. The respondents at southern district complained of the noise pollution by airplanes and factories at the afternoon and the respondents at northern district complained of the noise pollution by vehicles(P<0.05).

• Journal of Korean Society for Geospatial Information Science
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• v.22 no.3
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• pp.57-69
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• 2014

As of 2013, Korean population density is 505 persons per $1km^2$ and is ranked 3rd place in the most densely populated countries exception of city-states. It shows clearly the population is concentrated in the city area. To fulfil this urban concentration population demand, the enlargement and complexation of buildings, subway and other underground spaces connection tendency has been intensified, and it is need to construct the indoor spatial information DB as well as the accurate indoor surveying DB to promote people's safety and social welfare. In this study, Sadang station and Incheon National Airport were aimed for the construction of Wi-Fi AP location DB and RadioMap DB by collecting the indoor AP raw datas by using mobile device and those collected results were ran through the process of verification, supplementation, and analyzation. To evaluate the performance of constructed DB, 10 points in Incheon Airport- 3rd flr in block A, and 9 points in Sadang station-B1 were selected and calculated the estimated points and ran evaluation experiment using survey positioning error, which is distance between real position and the estimated position. The result shows that Incheon international airport's average and standard deviation was separately 17.81m, 17.79m and Sadang station's average and standard deviation was separately 22.64m, 23.74m. In Sadang station's case, the areas near the exit has low performance of surveying position due to fewer visible AP points than other areas. As total datas were examined except those position, it was verified that the user's location was mapping close position in surveying positioning by using constructed DB. It means that constructed DB contains correct Wi-Fi AP locations and radio wave patterns in object region, so it is considered that the indoor spatial information service based on constructed DB would be available.

• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.85-92
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• 2015

This study examined the settlement of a 1-2W type greenhouse using a timber pile, which was recently established on Gyehwa-do reclaimed land, in order to obtain base data for the construction of a greenhouse on reclaimed land. The results of this study are as follows. foundation and timber pile increased over time, irrespective of the interior and exterior of the upon investigation of the ground, it was confirmed that there was no soft rock stratum (bedrock), and that a sedimentary stratum existed under the fill deposit, which is estimated to have been reclaimed during the site renovation. It was also found that a weathered zone was located under the fill deposit and sedimentary stratum, and that the soil texture of the entire ground floor consisted of clay mixed with sand, silty clay, and granite gneiss, in that order, regardless of boreholes. In addition, the underground water level was 0.3m below ground, regardless of boreholes. Despite a slight difference, the settlement of the greenhouse or measurement sites (channels). With regard to the pillar inside the greenhouse, except in the case of CH-2, the data at a site located on the side wall of the greenhouse (wind barrier side) indicated vibrations of relatively larger amplitude. Moreover, the settlement showed a significant increase during a certain period, which was subsequently somewhat reversed. Based on these phenomena, it was verified that the settlement range of each site in the interior and exterior of the greenhouse was between 1.0 and 7.5mm at this time, except in the case of CH-1. The results of the regression analysis indicated good correlation, with the coefficient of determination by site ranging between 0.6362 and 0.9340. Furthermore, the coefficient of determination ranged between 0.6046 and 0.8822 on the exterior of the greenhouse, which is lower than inside the greenhouse, but still indicates significant correlation.

• Journal of the Korean Geographical Society
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• v.50 no.6
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• pp.571-605
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• 2015

This research revealed that 'Yipjiamlyu' in the Mukedeng's map is geographically 'a beginning point of underf low,' whose location is on the Heishigou's riverbed(E.L. 1,840m) in the NNE side of Daegakbong peak, and that 'Tomungangweon'(Heishigou) is one of the upstream reach of the Sungari River, which, according to historical documents and my fieldwork, Mukedeng also knew at the time of Yimjin(1712) Boundary Making and Demarcation(YBMD). These findings suggest the need to reinterpret the processes of YBMD. Mukedeng set up the Baekdusanjeonggyeobi on the mistaken assumptions on the linkage of 'Yipjiamlyu' and Tumen River. It should have been set up on the Daeyeonjibong peak. Mukedeng found the 'Yipjiamlyu' on the riverbed of 'Tomungangweon'(Heishigou), went downstream, and realized that this river did not flow into the Tumen River. During the search for the source of Tumen River, he found a water stream, and regarded it as the source of Tumen River. He speculated that the water at the 'Yipjiamlyu' flows through the underground to reappear at the his 'identified' source of Tumen River. Consequently, he adjured the construction of demarcation from Baekdusanjeonggyeobi through 'Yipjiamlyu' to the his 'identified' source of Tumen River. The water stream pointed as the source of Tumen River, however, was not part of the upstream reach of Tumen River. Actually, Korean officials, who were in charge of establishing boundary features, set up the demarcation from Baekdusanjeonggyeobi through Huanghuasongdianzi to the true source of Tumen River identified by themselves, which Mukedeng had not intended. The ambiguity of the location of 'Yipjiamlyu' caused a difference between Mukedeng's original request and Korean officials' implementation in the boundary demarcation. Throughout the whole processes of YBMD, Korea(Joseon) and China(Qing) both mistook the real geography of the river system. Their understanding on Yalu River system was correct. But the identification of the spring source of the Tumen River by Korean participants was the only geographically correct result related on this river system in YBMD.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.2
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• pp.27-40
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• 2021

This study was carried out for the description of the conflicts on the measurement of the root collar diameter of the landscape trees that are currently being produced, distributed, and planted in S. Korea, and for determination of the standard for root collar diameter measurement. The difference in consciousness of appropriate measurement of root collar diameter among different ages of landscape practitioners was statistically significant at p<0.05 level. It seemed to be due to the difference in the amount of field experiences among different age groups. On "the ambiguity of measuring the root collar diameter' of landscape trees", the consciousness was significantly different at p<0.05 level among job positions. On "Improvement of measurement criteria for landscape trees," it was significantly different at p<0.05 level among job types. This was thought to be due to the disagreement between the client and the contractor. On "prevention of topsoil removal" when excavating landscape trees, the consciousness was significantly different at p<0.001 level among different age groups, and different at p<0.01 level among different occupations, and different at p<0.05 level among different working area. The consciousness on "removing top soil when excavating landscape trees and rooting after transplantation" was not significantly different. The consciousness on the conflict caused by "ambiguity in root collar diameter measurement criteria" was high with an average of 3.85 for job type, occupation, jop position, and work experience. It was higher for landscape contractors than public institutions. The higher job positions and more experiences, the more conflicts. The consciousness on the appropriate position of root collar diameter measurement for landscape trees revealed that measuring at above-ground part (66.5%) was prefered to the underground part (33.0%). During the excavation of landscape trees for transplant, topsoil removal up to average depth of -2cm to -4cm was favored by 84.0%, and the purpose of removing topsoil was recognized as 'to increase the size and unit cost' by 59.7%.

• Korean Journal of Heritage: History & Science
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• v.46 no.4
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• pp.4-23
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• 2013

Songsalli Ancient Tombs of Gongju consists of seven tombs. King Muryeong's tomb, the seventh tomb, is a brick chamber tomb discovered during the drainage works for the fifth and the sixth tombs in 1971. The excavation at the time focused on topographic surveys of the tomb entrance and the inside of the burial chamber as well as collection of the remains. The burial mount survey confirmed the status of some stone slab remaining and lime-mixed soil layers, but the survey did not examine the exterior structure of the whole tomb as the mounds were removed even more deeply. The excavation revealed damages to the bricks and mural damages due to moisture and fungus in the sixth and the seventh tombs. Between 1996 and 1997, Gongju National University conducted a comprehensive detailed survey of Songsalli Ancient Tombs including a geophysical survey, with an aim to identify the root causes of such degradation. Based on the results, repair took place in 1999 and the fifth, sixth and seventh tombs were placed under permanent conservation to conserve the cultural assets. General public is currently denied access. The purpose of this study was to conduct a three-dimensional resistivity and GPR surveys on the ground surface of the fifth, sixth and seventh tombs of Songsalli Ancient Tombs in order to understand the underground status after repair. The study also aimed to understand the thickness of all the tomb walls and exterior structure based on GPR inside King Muryeong's tomb. The exploration on the ground surface found that the three tombs and soil adjacent to the tombs had resistivity as low as 5 to $90{\Omega}m$, which confirmed that the soil water content was still as high as that prior to the repair work. Additionally, GPR found that the wall construction of the burial chamber of King Muryeong's tomb was approximately 70cm in thickness, while the structure was of 2B with two bricks, about 35cm in length, put together longitudinally(2B brick masonry). The pathway to the burial chamber was of the 2B structure just like that of the burial chamber walls, while its thickness was 80cm with an eyebrow-type arch connected to it. Also, the ceiling exterior appears to have an arch structure, identical to the shape inside.

• Journal of the Korean GEO-environmental Society
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• v.24 no.12
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• pp.61-67
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• 2023

Heat pipes located underground in urban areas and operated under high temperature and pressure conditions can cause large-scale human and economic damage if damaged. In order to predict damage in advance, damage and construction information of heat pipe are analyzed to derive independent variables that have a correlation with frequency of damage, and a simple regression analysis modified model using each variable is applied to the field. However, as the correlation between independent variables applied to the model increases, the independence between variables is harmed and the reliability of the model decreases. In this study, the independence of the pipe diameter, burial depth, insulation level of monitoring system, and disconnection or short circuit of the detection line, which are judged to be interrelated, was tested to derive a method for combining variables and setting categories necessary to apply to the frequency of damage estimation model. For the test of independence, the continuous variables pipe diameter and burial depth were each converted into three categories, insulation level of monitoring system was converted into two categories, and the categorical variable disconnection or short circuit of the detection line status was kept as two categories. As a result of the test of independence, p-value between pipe diameter and burial depth, level of monitoring system and disconnection or short circuit of the detection line was lower than the significance level (α = 0.05), indicating a large correlation between them. Therefore, the pipe diameter and burial depth were combined into one variable, and the categories of the combined variable were set to 9 considering the previously set categories. The insulation level of monitoring system and the disconnection or short circuit of the detection line were also combined into one variable. Since the insulation level is unreliable when the detection line status is disconnection or short circuit, the categories of the combined variable were set to 3.

• Journal of Korean Institute of Fire Investigation
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• v.9 no.1
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• pp.103-121
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• 2006

We are living in more comfortable circumstances with the social developments and the improvement of the standard of living, but, on the other hand, we are exposed to an increase of the occurrences of tires on account of large-sized, higher stories, deeper underground building and the use of various energy resources. The materials of the floor in a residence modern society have been going through various alterations in accordance with the uses of a residence and are now used as final goods in interioring the bottom of apartments, houses and shops. There are so many kinds of materials you usually come in contact with, but in the first place, we need to make an experiment on the spread of the fire with the hypocaust used as the floors of apartments, etc. and the floor covers you usually can get easily. We, scientific investigators, can get in contact with the accidents caused by incendiarism or an accidental fire closely connected with petroleum stuffs on the floor materials that give rise to lots of problems. on this account, I'd like to propose that we conduct an experiment on fire shapes by each petroleum stuff and that discriminate an accidental tire from incendiarism. In an investigation, it seems that finding a live coal could be an essential part of clearing up the cause of a tire but it could not be the cause of a fire itself. And besides, all sorts of tire cases or fire accidents have some kind of legislation and standard to minimize and at an early stage cope with the damage by tires. That is to say, we are supposed to install each kind of electric apparatus, automatic alarm equipment, automatic fire extinguisher in order to protect ourselves from the danger of fires and check them at any time and also escape urgently in case of fire-outbreaking or build a tire-proof construction to prevent flames from proliferating to the neighboring areas. Namely, you should take several factors into consideration to investigate a cause of a case or an accident related to fire. That means it's not in reason for one investigator or one investigative team to make clear of the starting part and the cause of a tire. accordingly, in this thesis, explanations would be given set limits to the judgement and verification on the cause of a fire and the concrete tire-spreading part through investigation on the very spot that a fire broke out. The fire-discernment would also be focused on the early stage fire-spreading part fire-outbreaking resources, and I think the realities of police tire investigations and the problems are still a matter of debate. The cause of a fire must be examined into by logical judgement on the basis of abundant scientific knowledge and experience covering the whole of fire phenomena. The judgement of the cause should be made with fire-spreading situation at the spot as the central figure and in case of verifying, you are supposed to prove by the situational proof from the traces of the tire-spreading to the fire-outbreaking sources. The causal relation on a fire-outbreak should not be proved by arbitrary opinion far from concrete facts, and also there is much chance of making mistakes if you draw deduction from a coincidence. It is absolutely necessary you observe in an objective attitude and grasp the situation of a tire in the investigation of the cause. Having a look at the spot with a prejudice is not allowed. The source of tire-outbreak itself is likely to be considered as the cause of a tire and that makes us doubt about the results according to interests of the independent investigators. So to speak, they set about investigations, the police investigation in the hope of it not being incendiarism, the fire department in the hope of it not being problems in installments or equipments, insurance companies in the hope of it being any incendiarism, electric fields in the hope of it not being electric defects, the gas-related in the hope of it not being gas problems. You could not look forward to more fair investigation and break off their misgivings. It is because the firing source itself is known as the cause of a fire and civil or criminal responsibilities are respected to the firing source itself. On this occasion, investigating the cause of a fire should be conducted with research, investigation, emotion independent, and finally you should clear up the cause with the results put together.