• International Journal of Concrete Structures and Materials
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• v.7 no.1
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• pp.17-33
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• 2013

The most recent report by ACI Committee 440 on externally bonded fiber reinforced polymer (FRP) strengthening systems states that systems designed to mechanically anchor FRP should be studied in detail and substantiated by physical testing. To select and design an appropriate anchorage system for use in an FRP strengthening system, it is important that findings from previous research studies be known. This paper presents a comprehensive literature review of the performance of different mechanical anchorage systems used in FRP strengthening applications. Each anchorage system is discussed in terms of its purpose and performance. Advantages and disadvantages of each system are discussed, and areas in need of future research are explored.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.7 no.1
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• pp.10-16
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• 2011

Performance of ground-source heat pumps (GSHPs) is mainly affected by ground heat exchangers which makes up more than 40% of construction cost. Exact construction and grout as backfill are important, because it is difficult to repair after being installed. As grout materials, bentonite grout material and cement material are used In this paper, thermal conductivity according to mix proportion of cement grout has been experimentally studied. Some variables were set to evaluate thermal conductivities according to change in cement content, unit water ratio, mass per volume of fresh mortar, and aggregate types. From the experimental analysis, high performance cement grout has been proposed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.05a
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• pp.65-68
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• 2002

This study of concrete movement confronting a scope inspects the problems about the waterproofing method and leakage/repairement at present and research the mechanism with the variety of applying examples introducing adhesion and inflation using the flexible type of waterproofing and repairement and the substitution method developed with polymer resign composite. The polymer resign transmitted into adhesion or inflation materials under wet environment absorbs adjoining moisture, wraps impurities of concrete surface. get the waterproofing layer and concrete surface adhere toughly, reorganizes the impaired waterproofing layer and get over the detachment of it from concrete surface.

• Korean Journal of Environmental Agriculture
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• v.9 no.1
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• pp.61-68
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• 1990

The pressure to develop new agricultural technologies will be roughly proportional to the rate of depletion of natural resources employed in agriculture. Of these resources, land, water and gentic resources are critical. The development of agriculture is associated with a scientific and technological establishment, of remarkable capability ; responding rapidly to many problems encountered by the agricultural production. These advantages are also coupled with constraints. Agricultural systems are concerned with the efficient conversion of resources into products that are wanted by the producer or someone else who is prepared to pay for them. They are based on biological processes, but they are operated by the people for a multiplicity of purposes. Study of agricultural systems is aimed at helping in the operation of systems, their repair or their improvement. The future concerns of agriculture will center on (1) increasing and safeguarding the supplies of productive inputs to agriculture, (2) improving the efficiency with which these inputs are used in food production, (3) developing new sources of basic food materials, and (4) coping with the external costs that tend to appear in intensive, mechanized agriculture.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.97-105
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• 2004

The vertical roller mill is the important machine grinding and mixing various crude materials in the manufacturing process of portland cement. Table liner is one of grinding elements of vertical roller mill and is subjected to the cyclic bending stress by rollers and the centrifugal force by rotation of table. It demands $4{\times}10^7$ expense of life but has $4{\times}10^6~-8{\times}10^6$ cycle. It fractures at the edge of grinding path of outside roller The repair expense fur it amounts to 30% of total maintenance of vertical roller mill. Therefore, this study shows the fracture mechanism of table liner of vertical roller mill using HDM and fatigue analysis

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.925-928
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• 2004

The application of focused ion beam (FIB) technology in micro/nano machining has become increasingly popular. Its use in micro/nano machining has advantages over contemporary photolithography or other micro/nano machining technologies such as small feature resolution, the ability to process without masks and being accommodating for a variety of materials and geometries. This paper was carried out some experiments and verifications of mechanism on FIB-CVD using SMI8800 made by Seiko. FIB-CVD has in fact proved to be commercially useful for repair processes because the beam can be focused down to 0.05$\mu\textrm{m}$ dimensions and below and because the same tool can be used to sputter off material with sub-micrometer precision simply by turning off the gas ambient. Recently the chemical vapour deposition induced ion beam has been required more deposition rate and accurate pattern because of trying to manufacture many micro and nano parts. Therefore this paper suggested the optimization parameters and discussed some mechanism of chemical vapour deposition induced ion beam on FIB-CVD for simple pattern.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.497-502
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• 2001

We examined the silicate-based material to develop the surface-treatment agent, which would be used to restore performance of the deteriorated concrete and to inhibit corrosion of the reinforcing bar. As a part of the study, we carried out experiments of the penetration and strengthening properties of concrete treated by the considering agent. The variables of experiment, were the type of silicates, the ratio of distilled water-silicate, the usage of surface-strengthening material, and the usage of biochemical material. The penetrating ability of concrete is assessed by viscosity and surface tension. Also assessments of strengthening effects of concrete are performed on compressive strength, absorption, and water permeability tests.

• Journal of the Korean Arthroscopy Society
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• v.2 no.1
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• pp.40-44
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• 1998

The use of autogenous tissues is preferred for knee ligament reconstruction. However allografts play a role in major ligament reconstructive procedures in which multiple substitutions or revisions are required. In the dislocated knee, allografts may offer an advantage in reconstructing the PCL. But allografts in knee ligament surgery must be considered in terms of biomechanical and regenerative properties, disease transmission and immunogenecity, and methods of preservation and sterilization. Also only a few authors have described the use of allograft for reconstruction of a ruptured PCL, either a single procedure, or in combination with ACL repair following knee dislocation. Furthermore, the problems that the clinician faces with use of allografts is the necessity for supervision to ensure that the grafts are correctly processed, secondarily sterilized, and free of transmissible diseases. For these reasons, the routine use of allograft materials in the treatment of ligament deficiencies should be avoid and provide with meaningful outcome studies, including longterm follow-up.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.2
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• pp.70-83
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• 2001

The required standards for environmental tests for communication and electronic equipment used currently in the army are not standards into which the Korean climate and use environment are taken into consideration. But the environmental testing standards of the U.S. army at the time of its establishment(MIL-STD-810) “A” version has been used without taking into consideration the Korean domestic situation and conditions by simply translating the US standards. Adherence to these standards may limit the ability to supply materials in case of emergency since the increase in the manufacturing costs according to excessively strict standards induces an increase in the acquisition cost of military equipment, unnecessarily high maintenance and repair expenses are consumed, and stocks of parts for the military use have to be retained at all times.

• Journal of Chest Surgery
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• v.23 no.5
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• pp.1027-1034
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• 1990

Pectus excavatum, commonest developmental anomaly of chest wall, is manifested by depression of the sternum and lower costal cartilages that is of surgical interest. From 1982 through 1990, fifteen patients have undergone surgery for treatment of pectus excavatum and treated by Ravitch operation: 5, Modified Ravitch operation; 4, Wada operation, 1 and Modified Wada operation, 5. There was familial history of pectus excavatum in 3 patients. Associated congenital anomaly were seen in 6 patients; scoliosis in 3 patients, right inguinal hernia in 1, polydactyly in 1 and patent ductus arteriosus in 1 patent. Postoperative minor complications were developed in 3 cases; pneumothorax, 2 cases; pleural effusion, 2 cases; wound infection and dehiscence, 1 cases; pressure sore due to strut malposition, 2 cases; flail chest and 2 cases; seroma. The incidence of the postoperative complications were more common in cases who were treated by metal strut, pin or other prosthetic materials for supporting the chest wall integrity than the standard corrective procedure. All cases have no recurrence of chest wall depression and operative death.