• Title/Summary/Keyword: zones

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Predicting Single-hole Blast-induced Fracture Zone Using Finite Element Analysis

  • Jawad Ur Rehman;Duhee Park
    • Journal of the Korean GEO-environmental Society
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    • v.25 no.7
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    • pp.5-19
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    • 2024
  • During the blasting process, a fracture zone is formed in the vicinity of the blast hole. Any damage that extends beyond the excavation boundary line necessitates the implementation of an additional support system to assure safety. Typically, fracture zone radius is estimated from blast hole pressure using theoretical methods due to its simplicity. However, linear charge concentration (kg/m) is used for tunnel blasting. This paper compiles Swedish experimental datasets to estimate the radius of fracture zones based on linear charge concentration. Further numerical analyses are performed in LS-DYNA for coupled single-hole blasting. The Riedel-Hiermaier-Thoma (RHT) model has been selected as the constitutive model for this investigation. The numerical model is validated against small-scale laboratory tests. Parametric studies are conducted to predict fracture zones in granite and sandstone rocks using two kinds of explosives, PETN and AFNO. The analyses evaluate ten types of blast hole sizes, ranging from 17 to 100 mm. The results indicate that granite has a larger fracture zone than sandstone, and the PETN explosive predicts more damage than ANFO. Smaller blast holes exhibit smaller fracture zones in comparison to larger blast holes. Wave propagation is more rapidly attenuated in granite than in sandstone. Subsequently, the predicted fracture zone outcomes are compared with the empirical dataset. Fracture zones of medium blast hole diameter align well with the experimental data set. A predictive equation is derived from the data set, which may be used to evaluate blast design to manage fracture zones beyond the excavation line.

Agroclimatic Zone and Characters of the Area Subject to Climatic Disaster in Korea (농업 기후 지대 구분과 기상 재해 특성)

  • 최돈향;윤성호
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.s02
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    • pp.13-33
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    • 1989
  • Agroclimate should be analyzed and evaluated accurately to make better use of available chimatic resources for the establishment of optimum cropping systems. Introducing of appropriate cultivars and their cultivation techniques into classified agroclimatic zone could contribute to the stability and costs of crop production. To classify the agroclimatic zones, such climatic factors as temperature, precipitation, sunshine, humidity and wind were considered as major influencing factors on the crop growth and yield. For the classification of rice agroclimatic zones, precipitation and drought index during transplanting time, the first occurrence of effective growth temperature (above 15$^{\circ}C$) and its duration, the probability of low temperature occurrence, variation in temperature and sunshine hours, and climatic productivity index were used in the analysis. The agroclimatic zones for rice crop were classified into 19 zones as follows; (1) Taebaek Alpine Zone, (2) Taebaek Semi-Alpine Zone, (3) Sobaek Mountainous Zone, (4) Noryeong Sobaek Mountainous Zone, (5) Yeongnam Inland Mountainous Zone, (6) Northern Central Inland Zone, (7) Central Inland Zone, (8) Western Soebaek Inland Zone, (9) Noryeong Eastern and Western Inland Zone, (10) Honam Inland Zone, (ll) Yeongnam Basin Zone, (12) Yeongnam Inland Zone, (13) Western Central Plain Zone, (14) Southern Charyeong Plain Zone, (15) South Western Coastal Zone, (16) Southern Coastal Zone, (17) Northern Eastern Coastal Zone, (18) Central Eastern Coastal Zone, and (19) South Eastern Coastal Zone. The classification of agroclimatic zones for cropping systems was based on the rice agroclimatic zones considering zonal climatic factors for both summer and winter crops and traditional cropping systems. The agroclimatic zones were identified for cropping systems as follows: (I) Alpine Zone, (II) Mountainous Zone, (III) Central Northern Inland Zone, (IV) Central Northern West Coastal Zone, (V) Cental Southern West Coastal Zone, (VI) Gyeongbuk Inland Zone, (VII) Southern Inland Zone, (VIII) Southern Coastal Zone, and (IX) Eastern Coastal Zone. The agroclimatic zonal characteristics of climatic disasters under rice cultivation were identified: as frequent drought zones of (11) Yeongnam Basin Zone, (17) North Eastern Coastal Zone with the frequency of low temperature occurrence below 13$^{\circ}C$ at root setting stage above 9.1%, and (2) Taebaek Semi-Alpine Zone with cold injury during reproductive stages, as the thphoon and intensive precipitation zones of (10) Hanam Inland Zone, (15) Southern West Coastal Zone, (16) Southern Coastal Zone with more than 4 times of damage in a year and with typhoon path and heavy precipitation intensity concerned. Especially the three east coastal zones, (17), (18), and (19), were subjected to wind and flood damages 2 to 3 times a year as well as subjected to drought and cold temperature injury.

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AN OBSERVATION ON THE FRACTURE SYSTEMS OF THE SOUTHERN VIETNAM

  • Chang Sung Jin;Long Nguyen Tien
    • 한국석유지질학회:학술대회논문집
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    • autumn
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    • pp.6-22
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    • 2001
  • A study of the fracture systems in outcrops of southern onshore Vietnam revealed two kinds of fracture groups according to their origin: cooling fractures and deformation related fractures. Cooling of magma introduced extensive fractures in the batholiths with wide spacing and narrow aperture. They are found widespread in all magmatic bodies, but result in poor reservoir quality due to low bulk porosity and narrow aperture. Cooling fractures are often reactivated during later stress regimes. Deformation related fractures, especially 'fault damage zones' and 'hanging wall deformation' is thought to form the most important reservoir type in the fractured basement rock. The porosity formed by intense fracturing and fault breccia along minor fault zones is thought to be the producing zones in the producing fields of Cuu Long basin. They are found along major faults and widespread in hanging wall blocks.

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Reparation for Victims of the International Civil Aviation Arising from Armed Conflict Zones

  • Huaping, QIN
    • The Korean Journal of Air & Space Law and Policy
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    • v.30 no.1
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    • pp.245-271
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    • 2015
  • The downing of the MH17 reminds the world that the international civil aviation is not as safety and security as people expected. Such tragedy is partly due to the risk and danger of the armed conflict zones, but is more attributed to the ignorance to the international law by the responsible parties concerned. International laws applicable to the armed conflict zones shall be strictly followed, and the reparation shall be provided to the victims, otherwise such disaster could not be avoided in the future.

A Study on the Optimization of Coordinate System for Digital Mapping (수치지도 좌표체계의 최적화 방안에 관한 연구)

  • Kim, Yong-Il;Lee, Chang-No
    • Journal of Korean Society for Geospatial Information Science
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    • v.3 no.1 s.5
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    • pp.37-44
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    • 1995
  • Cartesian coordinate systems used in national base map have 3 zones. If these coordinate systems are used at navigable digital maps without modifications, the edge-matching errors will occur near the edge of two zones. Therefore, it's required to eliminate separate zones of national plane coordinates system suitable far navigable digital map, we choose TM projection that is used at national base map but changed the location and the scale distortion of antral meridian.

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방사성환기설비 운전에 있어서의 부압변동 요인 및 대응 방안

  • 이강무;이범철;이영희;김태국;손종식;홍권표;김홍태
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.334-335
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    • 2004
  • It is important that the contaminated air is not revealed to the outside of the facility. The inside of the facility should be classified into several zones according to the radioactivity and each zone should maintain tile differential negative pressure between the zones also. It is not easy to equilibrate the pressure during the operation. On the normal operation, the clogging of the HEPA filter and the opening of the doors/shutters influence very much. We could maintain the differential negative pressure between the zones by the constant watching and periodical replacement of the filters.

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A Comparison of the Alpine Tundra Floras of the Alpine Tundra Zone on Paektusan with the Alpine and Subalpine Zone in Korea (韓國에 있어서 白頭山의 高山툰드라대와 高山과 亞高山帶의 高山툰드라 植物相의 比較)

  • Chang, Nam-Kee;Yoo, Hae-Mee;Eo, Eun-Joo
    • The Korean Journal of Ecology
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    • v.13 no.3
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    • pp.237-245
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    • 1990
  • Ninety six plant species recorded at the alpine tundra zone on the Paektusan (Zhu and Rowe, 1987) were examined on the floras of alpine and subalpine zones in Korea. Among the 96 species, 59(61%), 47(49%) and 51(53%) species in the alpine zone of Kwanmobong, Turyusan and Puksubaeksan were recognized respectively, and 24(25%), 21(22%), 11(11%) and 16(17%) species in the subalpine zone of Myohyangsan, Kumgangsan, Soraksan, Chirisan and Hallasan respectively. The similarities between the alpine tundra zone of Paektusan and the alpine zones of other mountains in Korea showed high values than the values compared with subalpine zones.

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Economic Dispatch Using Hybrid Particle Swarm Optimization with Prohibited Operating Zones and Ramp Rate Limit Constraints

  • Prabakaran, S.;Senthilkuma, V.;Baskar, G.
    • Journal of Electrical Engineering and Technology
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    • v.10 no.4
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    • pp.1441-1452
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    • 2015
  • This paper proposes a new Hybrid Particle Swarm Optimization (HPSO) method that integrates the Evolutionary Programming (EP) and Particle Swarm Optimization (PSO) techniques. The proposed method is applied to solve Economic Dispatch(ED) problems considering prohibited operating zones, ramp rate limits, capacity limits and power balance constraints. In the proposed HPSO method, the best features of both EP and PSO are exploited, and it is capable of finding the most optimal solution for the non-linear optimization problems. For validating the proposed method, it has been tested on the standard three, six, fifteen and twenty unit test systems. The numerical results show that the proposed HPSO method is well suitable for solving non-linear economic dispatch problems, and it outperforms the EP, PSO and other modern metaheuristic optimization methods reported in the recent literatures.

ENDOCRINE (APUD) CELLS IN THE OVIDUCT OF THE SHEEP

  • Ogunranti, J.O.
    • Asian-Australasian Journal of Animal Sciences
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    • v.7 no.4
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    • pp.531-535
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    • 1994
  • APUD cells in the oviduct of the sheep at standing estrus were localized as paraneurons in the lamina propria sandwiched between this structure and the tunica muscularis by the method of masked metachromasia to toluidine blue after hot mineral acid hydrolysis. These were also confirmed by lead haematoxylin stain and argyrophilia. The oviduct was serialized into 66 zones. Cells were absent in the first and last 2 zones, and most parts of the isthmus. There was however abundant number of APUD cells in the ampulla which were fusiform shaped and were about $5{\mu}m$ width and also in the juncture, where the cells were of a smaller width ($3{\mu}m$) and were quite numerous reaching 180-200 in some zones. It is concluded that peptide secreting cells are numerous in the oviduct and that this may qualify the oviduct as an endocrine organ.

Limit state assessment of nodal zone capacity in strut-and-tie models

  • Tjhin, Tjen N.;Kuchma, Daniel A.
    • Computers and Concrete
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    • v.4 no.4
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    • pp.259-272
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    • 2007
  • A method based on the lower-bound theorem of limit analysis is presented for the capacity assessment of nodal zones in strut-and-tie models. The idealized geometry of the nodal zones is formed by the intersection of effective widths of the framing struts and ties. The stress distribution is estimated by dividing the nodal zones into constant stress triangles separated by lines of stress discontinuity. The strength adequacy is verified by comparing the biaxial stress field in each triangle with the corresponding failure criteria. The approach has been implemented in a computer-based strut-and-tie tool called CAST (Computer-Aided Strut-and-Tie). An application example is also presented to illustrate the approach.