• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.2
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• pp.161-166
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• 2020

In accordance with the amendment of the Industrial Safety and Health Act of 2007, Korea completely prohibited the import, distribution and manufacture of asbestos like Europe and Japan. Accordingly, the current problem of asbestos is the safe maintenance and disposal of asbestos construction material, the disposal of asbestos, and the final disposal of asbestos building materials. If the asbestos building material is made harmless, it may be classified as general waste or as recyclable waste. Therefore, this study evaluated the physical and chemical characterization of detoxified asbestos powder and the applicability of secondary products. In this study, it was found that applying the appropriate temperature and pressure for catalysis during asbestos desalination through low temperature chemical treatment was the most important factor.

• Economic and Environmental Geology
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• v.21 no.3
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• pp.277-285
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• 1988

The ELF-MT survey has been conducted at 9 points along the national road between the Sindangri and Dojonri area to study on the boundary between the Okchon and Choson systems, and subsurface geological structure of these two systems. Natural electromagnetic fields of 7.8, 14, and 20 Hz in the Schumann resonant frequency band were used for ELF-MT measurement. Apparent resistivity values were calculated from the measured magnetic and electric fields at each frequency, and resistivity sections were obtained by means of a trial and error method for one-dimensional analysis and finite element method for two-dimensioal analysis. The results of this study show that the resistivities of the Okchon and Choson systems are 700-3500 ohm-m and 40-5000 ohm-m, respectively. The boundary between these two systems is a fault with the width of 1 km fault zone and resistivity value of 200 ohm-m, and is located around Koburangjae. Another fault is appeared in Sindangri, and its resistivity value is 130 ohm-m. Intrusion of biotite granite is distributed in Jungchijae, and its resistivity value is 750 ohm-m. The area between Susanri and Koburangjae shows the highest resistivity value of 3500 ohm-m because metabasite and amphibolite are distributed in that area. Extremely low resistivity value of 40 ohm-m around Yongamsan is due to the Yongam formation, which is composed of graphitic black slate and overlying Choson Great Limestone group.

• KNOM Review
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• v.22 no.2
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• pp.12-21
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• 2019

There is a rapid development of experimental equipment and ICT technology in data-intensive scientific areas, thus, big data of more than exabyte size is being generated. However, the big data transmission technology does not satisfy the needs of the application researchers who utilize it. Various high-performance transmission technologies have been developed based on QoS(Quality of Service), but they also require changes in the clean slate method. On the other hand, ScienceDMZ technologies improve the performance of scientific big data transmission by bypassing the firewall that causes a big problem in transmission performance. In addition, it is possible to implement without changing the existing network. In this paper, we built ScienceDMZ in an international long-distance environment based on KREONET(Korea Research Environment Open NETwork), and we verified the performance. We also introduced how GPU platform could be linked in a distributed ScienceDMZ environment.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.4
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• pp.117-124
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• 2022

Recognizing the problem that the definition of the term pan-ock does not appear precisely in the dictionary, the definition of pan-ock was established through analysis by analyzing 183 cases of pan-ock searched in the Korean Classics DB and classifying them into buildings and ships. First of all, the 65 pan-ocks classified as architecture were used in various ways, such as residences, religious facilities, jang-pan-ocks, and prisons, depending on their use. Second, the 90 cases of pan-ock related to ships were the concept of houses that combine work and accommodation on ships. Finally, through military installations, literary expressions, and bureaucrats who have seen trains and wagons, Pan-ock uses boards. It can be used for walls or roofs only, or for both walls and roofs. Therefore, it is necessary to consider the case of the Joseon Dynasty with the definition of Pan-ock in the existing dictionary. In other words, Pan-ock refers to "houses, religious facilities, royal tombs, and prisons, with various uses and forms. In addition, it refers to the joining of only the wall or the roof with planks, or the joining of both the wall and the roof," suggesting a broader interpretation of the category.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.4
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• pp.59-66
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• 2022

This study is to investigate the old buildings that have been built more than 50 years ago, targeting the areas of Seongan and Jungang-dong, the historic urban area of Cheongju. Their types and distribution characteristics are as follows. 1) First, the old buildings existing in downtown Cheongju account for 21.4% of 1,070 out of the total 5,000 buildings. Among them, wooden buildings before the 1950s accounted for 60% of them, resulting in severe aging. 2) Second, by use, 728 detached houses and 276 neighborhood living facilities account for 93.8% of the total, with 16 offices and 12 religious facilities. By structure, there are wood 65%, masonry 30%, and reinforced concrete 5% (54 buildings). By number of floors, the first floor 90%, the second floor 7.3%, and the third floor or higher 2.7% (30 buildings). The roof material is 51.6% of earthenware, followed by slate, cement, and slab. 3) Third, the old buildings are scattered all over the streets, and are concentrated in Namju-dong, Nammun-ro 1-ga-dong, Seoun-dong, and Sudong at the foot of Uamsan Mountain, a former refugee village. Also old buildings are distributed in Seoun-dong and Seokgyo-dong where hanok(korean traditional houses) are concentrated, in Namju and Nammunro 1 ga-dong blocks connected by alleys, and in cul-de-sac all over the place.

• Geomechanics and Engineering
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• v.36 no.5
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• pp.465-474
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• 2024

Uniaxial compressive strength (UCS) is a critical geomechanical parameter that plays a significant role in the evaluation of rocks. The practice of indirectly estimating said characteristics is widespread due to the challenges associated with obtaining high-quality core samples. The primary aim of this study is to investigate the feasibility of utilizing the gene expression programming (GEP) technique for the purpose of forecasting the UCS for various rock categories, including Schist, Granite, Claystone, Travertine, Sandstone, Slate, Limestone, Marl, and Dolomite, which were sourced from a wide range of quarry sites. The present study utilized a total of 170 datasets, comprising Schmidt hammer (SH), porosity (n), point load index (Is(50)), and P-wave velocity (Vp), as the effective parameters in the model to determine their impact on the UCS. The UCS parameter was computed through the utilization of the GEP model, resulting in the generation of an equation. Subsequently, the efficacy of the GEP model and the resultant equation were assessed using various statistical evaluation metrics to determine their predictive capabilities. The outcomes indicate the prospective capacity of the GEP model and the resultant equation in forecasting the unconfined compressive strength (UCS). The significance of this study lies in its ability to enable geotechnical engineers to make estimations of the UCS of rocks, without the requirement of conducting expensive and time-consuming experimental tests. In particular, a user-friendly program was developed based on the GEP model to enable rapid and very accurate calculation of rock's UCS, doing away with the necessity for costly and time-consuming laboratory experiments.

• Geomechanics and Engineering
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• v.36 no.5
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• pp.511-525
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• 2024

Underground openings significantly affect the mechanical stability of underground spaces and create damaged zones. This study investigated the acoustic emission (AE) characteristics associated with the formation of damaged zones around circular openings. Uniaxial compression experiments were conducted on three types of rock specimens, namely, granite (GN-1 and GN-2), gabbro (GB), and slate (SL), containing a circular opening. AE and digital image correlation (DIC) techniques were used to monitor and evaluate the damaged zones near the circular openings. The AE characteristics were evaluated using AE parameters, including count, energy, amplitude, average frequency, and RA value. The DIC results revealed that the estimated diameters of the damaged zones of GN-1, GN-2, GB, and SL were 1.66D, 1.53D, 1.49D, and 1.9D, respectively. The average displacements at the surface of the damaged zones for these specimens were 0.814, 0.786, 0.661, and 0.673 mm, respectively, thus demonstrating a strong correlation with Young's modulus. The AE analysis with DIC revealed that tensile failure occurred in the direction parallel to the maximum compression axis as the load increased. Thus, this study provides fundamental data for a comprehensive analysis of damaged zones in underground openings and will facilitate the optimization of rock engineering projects and safety assessments thereof.

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.251-262
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• 2009

In this research dairy cattle barn facilities what are 4,198 houses hold over 50 heads were surveyed by scale and province. Full-time farms hold over 50 heads breed total 344,514 heads. Each of Farms holds 50 to 99 heads were 79.8 percent and breed average 82.1 heads. Dairy cattle barns were constructed september 1995 averagely. Each of barns have $1,740.0\;m^2$ scale. The construction type of dairy cattle barn was almost litter barn type 84.0%, freestyle type 5.1%, mooring+litter ground type 17.3% and other types 4.4%. The litter barn type was popular in small farms. But in large farms, freestyle type was popular than small farms. The construction type of dairy cattle barn was almost litter barn type 84.0%, freestyle type 5.1%, moohng+ltter ground type 17.3% and other types 4.4%. Type of dairy cattle robotic milking system was pipeline 41.5%, herringbone 22.8% and tandem 35.8%. The pipeline type was popular in small farms which have 50~99 heads. But in large farms which have over 200 heads, tandem type was popular than small farms. Proportion of floor type of dairy cattle barn was almost litter type 94.9%. Scraper type was popular in large farms than in small farms. Proportion of roof type of dairy cattle barn was slate 32.5%, vinyl 16.3%, sunlight 11.1%, panel 10.9, zinc plate 8.8 and steel plate 8.3%. Roof type was lots of slate type before 1995. But vinyl type is increasing after 1995. Proportion of wall type of dairy cattle barn was almost open type 83.3% and winch-curtain 26.8%. Utilization period of dairy cattle barn was 9.2 years about milker, 7.9 years about automatic feeder, 9.2 years about waterer and 10.4 years about electric facilities. In this results, there were lots of improvements about automatic feeder.

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.231-240
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• 2009

In this research pig house facilities what are 3,029 houses hold over 1000 heads were surveyed by scale and province. Full-time farms hold over 1000 heads breed total 7,229,892 heads. And farms breed 2,386.9 heads averagely. Pig houses were constructed august 1995 averagely. Each of houses have $3,017.2\;m^2$ scale. The construction type of pig house was winch-curtain type 77.2% which was most popular, confined type 51.3%, litter type 7.4% and loft type 4.6%. The winch-curtain type was popular than windowless type in pig farms which have 1,000-1,999 heads. But pig house construction type which have more than over 10,000 heads was windowless type more than winch-curtain type. Manure removing type was slurry 72.3% and scraper 38.5% in farms which have 1,000-1,999 heads. Manure removing type was slurry 83.3% in farms which have over 10,000 heads. Proportion of roof type of pig house was slate 51.2%, panel 46.1%. But in middle or small farms, slate type was only 25.0%. Proportion of wall type of pig house was 41.9%, block 21.9%, concrete 7.6%, winch-curtain 6.3%, and bnck 5.9%. Ventilation type of pig house was natural winch 46.1%, mechanical windowless 69.8% and mixed type 53.1%. So, mechanical windowless type was popular than natural winch type. Especially the farm scale is bigger the mechanical widowless type was more. Utilization period of pig house was 8.1 years about automatic feeder, 8.3 years about waterer, 8.2 years about electric facilities and 9.0 years about floor material. Thus, almost of facilities were used at least 8 years.

• Journal of Animal Environmental Science
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• v.1 no.1
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• pp.9-19
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• 1995

This study was carried out to investigate the effect of sawdust bedding barn on manure handing, management labour and physiological aspect of dairy cows, and then to establish the criteria on the optimum utilization method of sawdust bedding barn. 46 tie stall barns and 49 sawdust bedding barns were surveyed to cmopare the milk productivity between two different barns, and also 5 tie stall barns, 15 sawdust bedding barns and 1 rice hull bedding barn were selected to study the utilization situation of sawdust barn in Kyung-Ki province area. The major results obtained were as follows; 1. The roof material of sawdust barn were consisted of 66% vinyl house, 23% PVC light and 11% slate and galvanum coated tin. Most of the floor structure was earth ground with the rate of the approximately 82%. 2. The average occupied area of sawdust bed per cow was 15.2 $m^2$, depth that 30 cm and the utilization period was 12 months. 3. Milk Yield was significantly higher at sawdust barn than at tie stall barn(P<0.01). Bacterial and somatic cell count in raw milk were less at the sawdust barn than in tie stall barn. However, there was not significance difference between two barns. 4. The labour hour needed to cow management in the sawdust barn was approximately 48% of that of tie stall barn. 5. The temperature and moisture content measured in sawdust bed were closely affected by seasonal ambient temperature. The skin and hair of cow were much cleaner at the PVC light roofed sawdust barn than any other roof materials. 6. The additives used for improving of fermentation did not show any effect on temperature and moisture content in sawdust bed. When the ambient temperature was $30.4^{\circ}C$, the surface temperature of measured 1 cm above the sawdust bed was $12.2^{\circ}C$ lower and the temperature of 100 cm above the sawdust bed was $2.4^{\circ}C lower under shading net facility than that of vinyl roofed one.7. The hoof length of miking cow was 7.95 cm in tie stall and 9.19 cm in sawdust barn with high significance (P<0.01). And disease occurence such as mastitis and foot-rot tended to decrease in the sawdust barn. 8. The number of total bacteria and coliform bacteria were less in the sawdust bed compared with earth ground resting area. And a parasite strongyloides papillosus was detected but without any infected cow. 9. The nitrate($NO_3N$) content in non-roofed earth ground resting area and earth ground under the sawdust bed was likely to pollute the ground water. 10. In economic point of view, rice hull bedding barn was the cheapest among different systems. And in the sawdust bedding barn PVC light + slate roofed barn was most desirable, and vinyl roofed one the least.