• Journal of the Korean Society of Clothing and Textiles
• /
• v.36 no.4
• /
• pp.382-390
• /
• 2012

This study shows the optimum attachment of Two-Way Shape Memory Alloy (TWSMA) springs onto thermal liner and its sewing method for the mass production of fire fighter's intelligent turnout gear. SMA springs were attached to the fabric by four different methods and stitched by two different shapes (square and wave). The durability of the attached springs was tested by laundering up to 50 cycles. Examined were whether the springs would remain attached to the fabric after repeated laundering, the shape memory effect and reaction of the springs, and the anti-corrosiveness of the springs. A Human-Clothing-Environment simulator evaluated thermal insulation according to attachment methods, air layer volume, and stitch types. The findings showed that silicon attached springs remained intact after repeated laundering; in addition, repeated laundering did not influence the responsiveness and anti-corrosiveness of SMAs. Air volume had positive relations with the insulation. Attachment methods or stitch methods had limited impact on the thermal insulation. As a result, a wave type stitch with silicone attachment was suggested as the optimum method to attach the SMA springs onto the intelligent turnout gear for fire fighters.

• Journal of Forest and Environmental Science
• /
• v.33 no.3
• /
• pp.233-238
• /
• 2017

This study was carried out to figure out the number of logs for sawtimber by DBH and height class and to compare merchantable volume ratio by categorizing into sawtimber, lagging board and pulpwood, and others for Pinus densiflora, Pinus koraiensis, and Larix kaempferi. Logs for sawtimber were hardly produced in small DBH class of three species, but produced evidently from medium DBH class. In large DBH class, the number of logs for sawtimber were noticeably different among species: 4.3 logs for L. kaempferi, 2.6 logs for P. densiflora, and 1.0 logs for P. koraiensis on average. Similarly, merchantable volume ratio for sawtimber were largely different among species in large DBH class with higher than 15 m: 82% logs for L. kaempferi, 60% logs for P. densiflora, and 44% logs for P. koraiensis. When compared to the upper diameter and upper height by species with regard to the last log of a tree produced for sawtimber, upper diameter was smallest with 14.1 cm and upper height was highest with 12.2 m in L. kaempferi. Overall, L. kaempferi was considered as the more commercial species for sawtimber production than P. densiflora and P. koraiensis.

• Journal of Mechanical Science and Technology
• /
• v.19 no.9
• /
• pp.1773-1780
• /
• 2005

The process of mould design in the foundry industry has been based on the intuition and experience of foundry engineers and designers. To bring the industry to a more scientific basis the design process should be integrated with scientific analysis such as heat transfer. The production by foundry techniques is influenced by the geometry configuration, which affects the solidification conditions and subsequent cooling. Numerical simulation and/or experiments make possible the selection of adequate materials, reducing cycle times and minimizing production costs. The main propose of this work is to study the heat transfer phenomena in the mould considering the phase change of the cast-part. Due to complex geometry of the mould, a block unstructured grid and a generalized curvilinear formulation engaged with the finite volume method is described and applied. Two types of boundary conditions, diffusive and Newtonian, are used and compared. The developed numerical code is tested in real case and the main results are compared with experimental data. The results showed that the solidification time is about 6 seconds for diffusive boundary conditions and 14.8 seconds for Newtonian boundary conditions. The use of the block unstructured grid in combination with a generalized curvilinear formulation works well with the finite volume method and allows the development of more efficient algorithms with better capacity to describe the part contours through a lesser number of elements.

• Asian-Australasian Journal of Animal Sciences
• /
• v.7 no.2
• /
• pp.175-178
• /
• 1994

A study was conducted at Ijok, Malaysia, to determine the relationship of testicular measurements with libido and semen quality in tropical and imported temperate breeds of sheep. Ten rams each of Malin (M), Siamese Longtail (L), Cross of Merino with Border Leicester (C), Dorset (D) and Suffolk (S) were used for the study. Libido, semen volume and semen quality were recorded monthly for a year together with testicular length, width and circumference. The results showed that there were breed differences in volume and quality of semen where the tropical breeds had better semen compared to the temperate breeds. There was positive and significant correlation between testicle length and semen volume in all the breeds. Testicular length was found to be positively and significantly correlated with motility and sperm concentration in the tropical breeds (L and M). The relationship between libido and testicle measurements in the tropical breeds was not significant (p<0.05). There was variable relationship between the testicular measurements and libido in the temperate breeds where the relationship was significant and negative in breeds C and D and highly significant and positive in S. It was evident that the long testicles influenced the quality of the semen whereas testicles with greater circumference influenced the libido of the rams.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.56 no.3
• /
• pp.65-74
• /
• 2014

Water footprint is defined as the total volume of direct and indirect water used to produce a good and service by consumer or producer, and measured at the point of production based on virtual water concept. The green and blue water footprint refers to the volume of the rainwater and the irrigation water consumed, respectively. Crop water footprint is expected to be used as the basic data for agricultural water resources policies at production, consumption and trade aspect. Thus, it is necessary to estimate suitable green and blue water footprint for South Korea. The objective of this paper is to quantify the green and blue water footprint and usage of upland crops during the period 2001-2010. To estimate the water footprint, 43 upland crop production quantity and harvested area data were collected for 10 years and FAO Penman-Monteith equation was adopted for calculating crop water requirement. As the results, the water footprint of cereals, vegetables, fruits and oil crops accounted for 1,994, 165, 605, and 4,226 $m^3/ton$, respectively. The usage of water footprint for crop production has been estimated at 3,499 (green water) and 216 (blue water) $Mm^3/yr$ on average showing a tendency to decrease. Fruits and vegetables have the largest share in the green water usage, consuming about 1,200 and 1,060 $Mm^3/yr$ which are about 65 % of gross usage. The results of this study are expected to be understood by the agricultural water footprint as well as by the total water footprint from both a production and consumption perspective in Korea.

• Journal of Microbiology and Biotechnology
• /
• v.7 no.5
• /
• pp.345-351
• /
• 1997

An aqueous/organic two-phase reaction system was applied to the production of catechol using immobilized resting cells of Pseudomonas putida CY 400. Water/ethyl ether system was used because of high partition coefficient of catechol and thus to reduce the product inhibition and degradation. Among the tested immobilization carriers, polyacrylamide gel gave the highest catechol productivity. The immobilization seemed to protect the cells against solvent toxicity. From the simulation of reaction conditions based on two-phase models, it was found that there was an optimum acetate concentration at fixed benzoate and cell concentrations for the catechol productivity. A lower phase volume ratio (lower fraction of organic phase) gave a higher productivity. However, the substrate conversion was low at low phase volume ratio.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.11a
• /
• pp.41-42
• /
• 2015

The concrete aggregate generates carbon dioxide in production but its demanding is gradually increased in accordance with the depletion of natural resources. Therefore we evaluated compatibility and basic physical properties of Silicon manganese slag generated in iron production as an applicable concrete aggregate. In our test, the silicon maganese slag shows 2.8g/㎥ of density in 10mm of maximum particle size similar to a natural aggregate, and its absorption rate was 0.3% similar to the electric furnace slag. Unit volume weight and ratio of absolute volume was respectively 2,001㎏/㎥ and 51%. Strength properties of Silicon manganese slag will be evaluated with further studies and experiments.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.587-590
• /
• 2002

Build-to-Order (BTO) capabilities enable manufacturing firms to design, produce, and deliver a high volume of differentiated products that meet specific customer needs in timely manner as well as at close to mass-production prices. Aim of BTO is to simultaneously achieve customer responsiveness, cost efficiency, and high volume production. This paper attempts to define the BTO system and suggests the critical components for its realization. A case study is also described to show the impact of a successful BTO implementation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.405-408
• /
• 2004

The sheet parts are formed with dies conventionally. But this conventional forming process is not suited to small volume and varied production for the reason of high cost. For the solution of this problem, a new forming process, which is called CNC incremental sheet forming, is being introduced. This process can form sheet parts without die, and is very well suited to small volume and varied production in space flight and automobile. In this paper, dieless CNC forming system based on a machining center is developed. A special device to grasp and pull the blank sheet built in the machining center and tool path generation S/W from STL file of 3-D model are developed. Several sheet parts are incrementally formed to verify the effectiveness of the developed system.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.3
• /
• pp.149-157
• /
• 2000

Tool wear in the shearing process such as blanking, piercing and trimming is very important, because it has great effects on the dimensional accuracy, working efficiency and economy. Most of tools in the shearing process have the coated layer at surface fur good wear and corrosion resistance. When the surface of tool is teated, the wear Phenomena of coated surface layer and inner layer may be different. This paper describes a computer modelling technique by the finite element method in order to investigate the wear mechanism and to predict the wear profile of Ti-N coated tool in piercing process according to the volume of Production. Wear coefficients of the coated layer and inner layer are obtained through Pin-on-Disk wear test, respectively. To verify the effectiveness of the suggested technique, the technique is applied to wear analysis in piercing recess of piston pin and simulation results are compared with experimental ones.