• 한국의류산업학회지
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• 제13권4호
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• pp.635-643
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• 2011

This study was investigated to evaluate the physiological responses on T-shirts manufactured with selected functional materials by body parts which were selectioned on the distribution of sweating and temperature change. Seven healthy men in twenties were participated in a climate chamber of $27{\pm}0.5^{\circ}C$ and $50{\pm}1%RHC$. Three kinds of T-shirts named 'D1', 'D2' and 'Poly' were used as experimental clothings. Four kinds of functional materials of quick absorbing/drying were used in all section in 'D1', but two kinds of functional materials used partially in 'D2'. 'Poly' T-shirts used only polyester. In an experimental schedule of 90 minutes, which were consisted of 'Rest', twice of 'Exercise' and twice of 'Recovery' periods, the subjects walked on a treadmill with 60% of $VO_2max$. As a physiological responses, the microclimate temperature, surface temperature(skin, clothing) and sweat rate were measured. Temperature regulation was kept well in 'D1' rather than other T-shirts. The quick absorbing/drying T-shirts showed its performance well as the exercise goes on the second half. With these results in mind, 'D1' will be more effective for long hours exercise such as climbing rather than short hours exercise.

• 한국생활과학회지
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• 제14권6호
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• pp.1037-1046
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• 2005

Using three consecutive years' harvested rices and their starches isolated from rice flours by alkaline method, it was found that no significant aging effect on rice flour and starch was observed based on following results. Proximate data of flours or starches showed in similarity, except high level of crude fat in rice flour and rice starch harvested in 2002. In SEM, the surface of aged rice flour had slightly layered shape due to possible abrasion during storage, and that of aged starch showed more smooth and less rigid polygonal shape. X-ray diffraction patterns of flours and starches were all A type, and crystallinity of rice starch harvested in 2000 had the smallest. From tristimulus colorimetry (Hunterlab Color), total color difference ($\Delta$E) calculated from L, a, and b gave less color difference with the darkest in 2002 harvested one among flours and the lightest in 2001 one among starches. WBCs of both 2002 rice flour and starch were the lowest among samples studied. At 80$^{\circ}C$, swelling power and solubility of rice starches harvested in 2000, 2001 and 2002 were 14.35, 9.75; 14.04, 9.6; and 12.49, 8.82, respectively. The highest peak viscosities measured by RVA were shown both in 2001 rice flour and in its starch. Starch and milled rice flour harvested in 2000 had higher hydrolytic $\alpha$-amylase, compared to other flour and starch samples.

• 펄프종이기술
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• 제43권2호
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• pp.49-56
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• 2011

Mulching technique is used to control the temperature and moisture content of soil by covering the ground surface. Most kinds of mulching film are made of polyethylene which is non-biodegradable synthetic polymer. Utilizing these films has been one of the main sources in soil pollution. Thus residual films under the ground should be removed after a certain period of time. Therefore, an alternative mulching material made of biodegradable functional paper is considered instead of non-biodegradable films. The mulching sheet produced from paper basis has a functionality to be naturally degraded and then recycled to the bio-materials on soil. In this study, the paper based-mulching sheet coated with biodegradable polymer was specially produced using a laboratory bar coater. Coating colors prepared by dissolving PBS/PLA in chloroform were applied to kraft paper. The mechanical strength and aging properties of this mulching sheet were investigated. The burst strength of polymer-coated paper was decreased with the increase of the PBS ratio in PBS/PLA blends, and, in particular, 30/70 blending condition led to good stability in heat-aging atmosphere for 60 days.

• 한국자동차공학회논문집
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• 제15권3호
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• pp.10-17
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• 2007

Design of experiments (DOE) technique has been used to design an exhaust heat exchanger to reduce the exhaust gas temperature under high load conditions in a spark-ignition engine. The DOE evaluates the influence and the interaction of a selected eight design parameters of the heat exchanger affecting the cooling performance of the exhaust gas through a limited number of experiments. The heat exchanger was installed between the exhaust manifold and the inlet of the close-coupled catalytic converter (CCC) to reduce thermal aging. To maximize the heat transfer between exhaust gas and coolant, fins were implemented at the inner surface of the heat exchanger. The design parameters consist of the fin geometry (length, thickness, arrangement, and number of fin), coolant direction, heat exchanger wall thickness, and the length of the heat exchanger. The acceptable range of each design parameter is discussed by analyzing the DOE results.

• 한국신뢰성학회지:신뢰성응용연구
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• 제1권2호
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• pp.79-93
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• 2001

Recently, new aspects of paints such as a beautiful appearance, use of environmentally friendly paints, etc., in addition to the superior performance of paints have been requested for industrial paints including the paints for heavy construction equipment and others. Particularly, the quality of appearance of coating affects the sales of heavy construction equipment. And the necessity for the paints to have a superior weather-proof property without changing the luster or color even after long-time exposure to the open air is emphasized. The change in the surface color and luster of the paint due to the natural environment progresses very slowly, and it takes a long time to verify material properties when developing new paints. In order to improve such methods, weathering tests are performed in many laboratories as a test for accelerating aging of coating, and the lifetime of the products is estimated through evaluation of the weathering (environment-proof) quality of paints. However, not a great deal of research activity has been conducted up to the present time since the interrelationship between the actual results of testing and field data is different for each paint and it takes a long time to study relevant materials. Therefore, introduced in the present study is the estimation of the change in the quality of appearance of coating in the field through the accelerated aging test among the cases of improvement of the quality of appearance of the urethane paint for heavy construction equipment.

• 한국식품영양학회지
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• 제28권2호
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• pp.189-195
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• 2015

Failure of the functions involved in ingestion leads to, not only loss of enjoyment of eating, but also protein-energy malnutrition. Dysmasesis and difficulty of swallowing occurs in various diseases, but aging is a major cause. In the aging society, the proportion of elderly people with dysmasesis and difficulty of swallowing is expected to increase rapidly. Developing foods for the elderly that are easy to chew and swallow is thus required. This study was conducted to develop easily chewable and swallowable foods for the elderly who can crush foods and ingest with their own tongues, but occasionally have difficulty in drinking fluids such as water and tea. Various foods for the elderly with chewing and swallowing difficulties were used for sensory assessment. The sensory panel consisted of 10 dietitians (10 women) in nursing care facilities. The sensory optimal composite recipes were determined by central composite design (CCD). The sensory measurements were significantly different in saltiness (p<0.05), sweetness (p<0.05), and overall quality (p<0.05). The optimum formulation of stir fried anchovy calculated by numerical and graphical methods was 3.74 g of soy sauces and 30.17 g of oligo-saccharides. Stir fried anchovy had a moisture content, hardness and adhesiveness of 76.52%, 2.10, and -1.57, respectively.

• 대한금속재료학회지
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• 제48권10호
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• pp.914-921
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• 2010

Studies were carried out to assess the microstructural and mechanical properties of ferriticmartensitic steel under a flowing sodium environment. HT9 (12Cr-MoVW) and Gr.92 (9Cr-MoVNbW) steel were exposed to liquid sodium at $650^{\circ}C$ containing dissolved oxygen of 20 ppm for 2333 hours and evaluations of the microstructure as well as the mechanical properties of the microhardness and nanoindentation were carried out. The result showed that both HT9 and Gr.92 exhibited macroscopic weight loss caused by general corrosion as well as localized types such as intergranular corrosion and pitting. Decarburization at the steel surface took place as the test proceeded. As the Cr content increased, dissolution and decarburization were suppressed. Assessment of the actual cladding geometry revealed that an aging process rather than decarburization governed the mechanical properties, which resulted in a decrease of the microhardness and yield stress.

• 한국주조공학회지
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• 제40권6호
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• pp.135-145
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• 2020

Aluminum cast iron has excellent oxidation resistance, sulfurization resistance, and corrosion resistance. However, the ductility at room temperature is insufficient, and at temperatures above 600?, the strength drops sharply and practicality is limited. In the case of heat-resistant cast iron, high-temperature materials containing Cr and Ni account for 30 to 50% or more. However, these high-temperature materials are expensive. Aluminum heat-resistant cast iron is considered as a substitute for expensive heat-resistant materials. Oxidation due to the aging temperature and holding time conditions increases more in 0 wt.% Al-cast iron than in 2 and 4 wt.% Al-cast iron according to oxidized weight and gravimetric oxide layer thickness measurements. As a result of observing the cross-section of the oxide layer, it was found to contain 0 wt.% of Al-cast iron silicon oxide-containing SiO₂ or Fe₂SiO₄ oxide film. In cast iron containing aluminum, the thickness of the internal oxide layer due to aluminum increases as the aging temperature and retention time increase, and the amount of the iron oxide layer generated on the surface decreases.

• Animal Bioscience
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• 제34권10호
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• pp.1705-1716
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• 2021

Objective: This study aimed to elucidate the effects of cooking conditions on the physicochemical and sensory characteristics of dry- and wet-aged beef strip loins. Methods: Dry- and wet-aged beef aged for 28 days were cooked using different cooking methods (grilling or oven roasting)×cooking temperatures (150℃ or 230℃), and their pH, 2-thiobarbituric acid reactive substances (TBARS), volatile compounds, and color were measured. Results: Cooking conditions did not affect pH; however, grilling resulted in lower TBARS but higher cooking doneness at the dry-aged beef surface compared to oven roasting (p<0.05). In descriptive sensory analysis, the roasted flavor of dry-aged beef was significantly stronger when grill-cooked compared to oven roasting. Dry-aged beef grill-cooked at 150℃ presented a higher intensity of cheesy flavor, and that grilled at 230℃ showed a greater intensity of roasted flavor compared to wet-aged beef at the same condition, respectively. Conclusion: Grilling may be effective for enhancing the unique flavor in dry-aged beef.

• 한국축산식품학회지
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• 제26권1호
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• pp.85-91
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• 2006

한국 전통 장류를 이용한 양념 돈육의 저장 안정성에 관한 연구로 돼지고기의 등심을 채취하여 $5{\times}15{\times}5\;cm$ 크기로 자른 후 육을 동일한 비율의 양념액에 침지하여 $1{\pm}1^{\circ}C$에서 28일간 숙성하면서 양념육(간장소스 양념육, T1; 고추장소스 양념육, T2; 된장소스 양념육, T3)의 품질 특성을 조사하였다. 양념육의 표면 육색은 소스의 영향을 많이 받았으며 간장 소스로 양념한 돈육의 명도는 낮게, 고추장소스로 양념한 돈육의 적색도는 높게, 된장 소스로 양념한 돈육의 명도는 높게 나타났다. 심부 육색의 명도는 모든 처리구에서 숙성기간에 따라 감소하였으며, 간장 소스로 양념한 돈육에서는 낮게 나타났다. TBARS는 간장 소스로 양념한 돈육이 다른 처리구에 비해 낮게 나타났으며 전 숙성기간 동안 증가하였다. 총균수는 모든 처리구에서 숙성기간에 따라 증가하였으며 간장 소스로 양념한 처리구가 다른 처리구에 비해 전 숙성기간 동안 낮은 총균수를 나타내었다. 대장균 수는 숙성 초기 $2.7{\sim}3.27\;log_{10}CFU/g$으로 다소 높게 나타났으나 숙성기간의 증가에 따라 처리구들에서 감소하였으며, 고추장 소스로 양념한 처리구는 숙성 14일에 된장소스로 양념한 처리구는 숙성 28일에 대장균이 나타나지 않았다. 유산균 수는 간장 소스로 양념한 처리구에서 숙성기간 동안 유산균수의 증가가 나타나지 않았으며, 고추장 소스로 양념한 처리구와 된장 소스로 양념한 처리구에서는 숙성기간에 따라 증가하였다.