• Journal of the Korean Ceramic Society
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• v.40 no.7
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• pp.677-682
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• 2003

The physical properties of sintered body made from 3 kinds of slip, F (Flocculated), M (Moderate), and D (Dispersed) for coal fly ash 70-clay 30 (wt%) were studied in terms of slip states and pore size distribution of sintered bodies. The floc particle size distribution for slip F was wider than slip D and the slip F contained flocs larger than 11 $\mu\textrm{m}$. The pore size distribution of the green body of all slips ranged over 1∼4 $\mu\textrm{m}$. The pores smaller than 1 $\mu\textrm{m}$ almost disappeared during the sintering process, while the larger pore of 2.5∼3 $\mu\textrm{m}$ growed by 1 $\mu\textrm{m}$. The pore distribution for the green body of slip F became a narrow in width and high in height after sintering and the large pore limit in a slip F sintered body was 5.1 $\mu\textrm{m}$ which is smaller than that of other slip. The slip F rather flocculated was favorable over slip D well dispersed, in offering a higher compressive strength. From these results, the mechanical strength of sintered body is dependent on the pore distribution which could be controlled by dispersion state of the slips.

• Journal of Navigation and Port Research
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• v.29 no.7
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• pp.641-646
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• 2005

In cargo-working, it unavoidably happens that the quay crane slip along the rail and the container move from side to side. Especially, they involve a lot of risk in bad weather. The rail clamp is a mooring device to prevent that the quay crane slips along the rail due to bad weather or the wind blast while the quay crane do the cargo-working And it will play a greater role in port container terminal integration and automation To design the wedge type rail clamp, it is very important to determine the wedge angle. In this study, we expect that the design wind speed of the quay crane will change over 16m/s. Assuming that the design wind speed is 40m/s, we determined the proper wedge angle of the wedge type rail clamp for the 50ton class quay crane.

• Structural Engineering and Mechanics
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• v.22 no.3
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• pp.263-278
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• 2006

Starting with the geometrically non-linear formulation and the subsequent linearization, this paper presents a consistent formulation of the exact mechanical analysis of geometrically and materially linear three-layer continuous planar beams. Each layer of the beam is described by the geometrically linear beam theory. Constitutive laws of layer materials and relationships between interlayer slips and shear stresses at the interface are assumed to be linear elastic. The formulation is first applied in the analysis of a three-layer simply supported beam. The results are compared to those of Goodman and Popov (1968) and to those obtained from the formulation of the European code for timber structures, Eurocode 5 (1993). Comparisons show that the present and the Goodman and Popov (1968) results agree completely, while the Eurocode 5 (1993) results differ to a certain degree. Next, the analytical solution is used in formulating a general procedure for the analysis of layered continuous beams. The applications show the qualitative and quantitative effects of the layer and the interlayer slip stiffnesses on internal forces, stresses and deflections of composite continuous beams.

• Journal of Industrial Technology
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• v.21 no.B
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• pp.341-348
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• 2001

The effect of initial ${\alpha}^{\prime}$ in STS 304 Stainless Steel on fatigue resistance, and fatigue crack propagation behavior was studied with using C-T specimens. Higher ${\Delta}K_{th}$ was observed in the specimens with the content of 0% initial ${\alpha}^{\prime}$ than in the contents of 2% and 33% initial ${\alpha}^{\prime}$. The difference of da/dN at the same level of ${\Delta}K$ was distinctive in low and intermediate level of ${\Delta}K$ however became less different as the level of ${\Delta}K$ increased. It is because the formation of strain induced martensite occurred readily in lower ${\alpha}^{\prime}$ at the vicinity of the fatigue crack tip, which causes compressive residual stresses resulting in the enhancement of crack closure. In general fatigue cracks propagated transgranular mode and many segments of ridges were observed on the fracture surfaces. At the higher contents of initial ${\alpha}^{\prime}$ appeared the smaller size of ridge segments. Slips in austenite were blocked more frequently by the martensite colonies formed in austenite.

• Magazine of the Korea Concrete Institute
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• v.6 no.6
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• pp.143-150
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• 1994

Most widened bridges have been constructed by the joining-construction method that makes new and existmg bridges structurally a single structure. Since the joining-constructiori method has several problems in design and construction viewpoint, this study is conducted in order to investigate the flexural fatigue behavior of RC slabs, which are widened and influenced by traffic-induced vibration of existmg bridge during placing and curing of new concrete, with the prototype fatigue test. It was found that stress concentration at the jclmts anti slips between steel bar and concrete are occured. Hut, the general tx:havinrs are similar to the original state and joining-construction method using expansive concrete nut~gated the influence of the trafflc-induced vibration.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.4
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• pp.614-622
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• 2014

The aim of this study is to research attributes of fishermen's occupational accidents for investigating the measure of risk control on situational condition in the Korean offshore and coastal fishing vessel. Using data of fishermen's occupational accidents are from National federation of fisheries cooperatives for 2013. The results were as belows; Occupational accident occurrence rate was 29.5‰, slips & trips and struck by object and contact with gear were shown severe occurrence pattern. Occupational accident occurrence rate of offshore fisheries was 130.2‰, coastal was 16.9‰, specially the risk rates were severely high in several type of danish seine, stow net and offshore trap. Death rate by accidents was 10.6‰ and by fall into the water in occurrence pattern was 5.5‰.

• Journal of the Korean Dietetic Association
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• v.16 no.4
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• pp.318-331
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• 2010

The objectives of this study were to investigate the status of accidents and to assess hazards in institutional foodservices in the Changwon and Masan areas. A survey was conducted from February 1 to March 31, 2009 using questionnaires, and 142 dietitians participated. The dietitians' perception of accident risks in workplace averaged 3.11 points. Forty-five percent of the respondents responded that accidents had occurred more than once between 2006 and 2008. In addition, 28.2% of the respondents experienced employee absences or turnover due to accidents during Year 2008. 'Musculoskelectal injuries or disorders (65.5%)', 'slips or falls (64.8%)', 'burns (57.7%)', and 'cuts and punctures (48.6%)' were the predominant accidents in foodservice. 'Knives (76 points)', 'steam kettles (41 points)', 'vegetable cutters (34 points)' and 'turn kettles (26 points)' were the equipment with severe accidents, such as burns or cut injuries. Among foodservice processes, 'carpal tunnel syndrome while washing (2.83 points)', 'burned by frying oil (2.64 points)', 'cut by sharp tools (2.55 points)', 'musculoskelectal injury by moving heavy weight food materials (2.41 points)', and 'injury by slipping on wet workplace floors and trenches (2.19 points)' were the most frequently occurring accidents at foodservice sites. To prevent safety accidents, dietitians' perceptions of safety supervision should be improved, and therefore, it is necessary they receive safety education.

• Fashion & Textile Research Journal
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• v.15 no.6
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• pp.1000-1009
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• 2013

Well-fitting riding breeches provide a comfortable ride. Horse-riding breeches should fit the lower body with patches located on the inside of hip and knees to prevent tears and slips. This study provides information about the fit of women's breeches using 3D human body scan data wearing commercially available two breeches according to posture. To get information about breeches fit, we measured the angle of waist line, the length, and the area of the breeches fit on four 20's women. This research showed the problem which was down for waist back line in the case of the horseback riding pose. The back waistline of the riding breeches should be raised compared to the front waistline; subsequently, an increased waistline angle results in less back waistline decrease. The breeches have plenty of length from back waist to crotch so the breech fit can be improved. The thigh circumference increased when riding in the front; therefore, good elasticity of the weft direction of the fabric is recommended. The length increase and the peripheral increase of the front knee significantly increased the surface area of the knee; consequently, knee patch material should be a two-way elastic fabric in all directions to enhance comfort according to riding motion.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.12 s.189
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• pp.103-110
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• 2006

The rail clamp is very important device to prevent that a container crane slips along a rail due to the wind blast as well as to locate the crane in the set position during an operating mode. Recently, the design wind speed criteria were intensified from the wind speed of 16m/s to 35m/s during an operating mode, and from 50m/s to 75m/s during a stowed mode in Korea, according to the 'Inspection Criteria for Facilities and Equipments in Port' reformed after typhoon 'Maemi'. In order to design the wedge type rail clamp for the reinforced design wind speed criteria of 35m/s, we carried out the finite element analysis of the rail clamp with respect to the wedge angle, and analyzed the relationship between the wedge angle and the sliding distance of the rail clamp.

• Journal of the Korean Society of Safety
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• v.27 no.5
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• pp.179-184
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• 2012

This study was performed to find out the measurement criteria of slip resistance from analysis of human gait and slips. Many kinds of slip resistance testers were developed based on mechanical friction testers. But, there are, as yet, no unambiguous slip resistance measurement methodologies and generally accepted safety criteria or safety thresholds for estimating slipping hazard exposures. Also, there are variety of measuring conditions between those testers. The measurement criteria should be tested within the range of human slipping conditions observed in biomechanical studies. It's results should clearly consider whether the devices reflect the human slipping conditions. In this study a dragsled type friction tester, which was constructed in accordance with ISO 15133 basically, was used. Test conditions were set in order to determine the range of measurement criteria. It is shown that drag velocity should be more than 1 m/s, acceleration be more than 10 $m/s^2$, contact time be less than 0.1sec, and contact pressure be within 350~400 kPa.