• Safety and Health at Work
• /
• 제10권2호
• /
• pp.219-223
• /
• 2019

Background: Ice cooling vests can cause tissue damage and have no flexibility. Therefore, these two undesirable properties of ice cooling vest were optimized, and the present study was aimed to compare the impact of the optimized ice cooling vest and a commercial paraffin cooling vest on physiological and perceptual strain under controlled conditions. Methods: For optimizing, hydrogel was used to increase the flexibility and a layer of the ethylene vinyl acetate foam was placed into the inside layer of packs to prevent tissue damage. Then, 15 men with an optimized ice cooling vest, with a commercial paraffin cooling vest, and without a cooling vest performed tests including exercise on a treadmill (speed of 2.8 km/hr and slope of %0) under hot ($40^{\circ}C$) and dry (40 %) condition for 60 min. The physiological strain index and skin temperature were measured every 5 and 15 minutes, respectively. The heat strain score index and perceptual strain index were also assessed every 15 minutes. Results: The mean values of the physiological and perceptual indices differed significantly between exercise with and without cooling vests (P < 0.05). However, the difference of the mean values of the indices except the value of the skin temperature during the exercises with the commercial paraffin cooling vest and the optimized ice cooling vest was not significant (P > 0.05). Conclusions: The optimized ice cooling vest was as effective as the commercial paraffin cooling vest to control the thermal strain. However, ice has a greater latent heat and less production cost.

• 산업기술연구
• /
• 제32권A호
• /
• pp.29-33
• /
• 2012

We demonstrated the viability of fully microfabricating SWCNT(single-wall carbon nanotube) film strain sensors for force and weight sensing. Our spray-deposited SWCNT film strain sensors showed good linearity over a range from 0 to 400 microstrain, and much higher sensitivity compared to commercial metal foil-type gauges. The number of grids and the thickness of the SWCNT film were found to have a significant effect on the strain sensing properties of the SWCNT film gauges. A strain sensing methode for the CNT-based strain gauges was also investigated using a binocular type beam load cells. Preliminary results indicate that the microfabrication method shown here is promising for developing a commercial strain gauge using a spray-coated SWCNT thin film. In the near future, various studies will be performed to further enhance the properties of the spray-coated SWCNT film strain sensors.

• 한국가금학회지
• /
• 제17권1호
• /
• pp.7-15
• /
• 1990

본 연구는 재래형 유색계통계와 상업용 백색 산난계의 혈중 지질과 단백질 함양을 비교하기 위하여 재래형 유색계통계로서 황갈색계 10수, 녹흑색학 13수, 백색계 7수, 오골계 10수를, 개량형으로서 상업용 백색산난계(Nick chick) 30수를 선정하여 동일한 사료를 1개월 간 급이한 다음 혈청중 Cholesterol, triglyceride 및 protein 함양을 측정한 결과를 요약하면 다음과 같다. 1. 혈청 cholesterol 함양은 상업용 백색산난계 ($172.50\pm$13.45 mg/100 $m\ell$)에서 고도의 유의차(P＜0.01)를 보였고 유색계통보다는 백색계통계에서 다소 높았고 유색계통간은 비슷했다. 2. 혈청 triglyceride 함양은 재래형 유색계간에는 차이가 없으나 상업용 산난계에서 유의성을 나타냈다. (p＜0.01) 3. 혈청 protein 합양은 상업용 산란계에서 $6.24\pm$0.23 mg/100 $m\ell$으로서 재래형보다 유의하게 높게 나타났다. (p＜0.01) 이상과 같이 재내형 유색계통보다 상업용 산난계에서 혈중 지질과 protein 농도가 높은 것은 닭의 개량정도에 의한 차이로서 상업용 산란계는 섭취한 사료의 영양소 흡수율이 높았기 때문인 것으로 사료된다.

• 한국소음진동공학회논문집
• /
• 제16권4호
• /
• pp.372-379
• /
• 2006

Little attention has been paid to static-strain-dependence of dynamic complex modulus of viscolelastic materials in computational analysisso far. Current commercial Finite Element Method (FEM) codes do not take such characteristics into consideration in constitutive equations of viscoelastic materials. Recent experimental observations that static-strain-dependence of dynamic complex modulus of viscolelastic materials, especially filled rubbers, are significant, however, require that solutions somehow are necessary. In this study, a simple technique of using a commercial FEM code, ABAQUS, is introduced, which seems to be far more cost/time saving than development of a new software with such capabilities. A static-strain-dependent correction factor is used to reflect the influence of static-strains in Merman model, which is currently the base of the ABAQUS. The proposed technique is applied to viscoelastic components of rather complicated shape to predict the dynamic stiffness under static-strain and the predictions are compared with experimental results.

• 한국육종학회지
• /
• 제40권2호
• /
• pp.106-112
• /
• 2008

International conferences to block the spread of Avian bird flu occurred in Beijing, 2006 and others warned of the seriousness of the H5N1 strain. The meetings succeeded in generating billions of dollars from USA, EU and World Bank. Migratory birds seem to play a major role in the spread of the aggressive strain globally from Asia to Europe and Africa. Experiences of tolerance breeding of maize (Zea mays L.) for four decades against 20 biotic stresses suggest that the prime cause of the occurrence of H5N1 strain was due to the human beings' counter-efforts against nature. Excessive use of chemicals (spray and injection) in the commercial poultry farms had created high selection pressure on virus. The new strain had mutated for survival. Attempting to eliminate the virus by chemicals for 100% control is a dangerous way to control biotic stresses. This can create more aggressive strains. A solution would be to build up tolerability of the commercial animals against the virus. Improvement of poultry cage environments and respect for nature must be integrated. Potential foes must be watched.

• Journal of Applied Biological Chemistry
• /
• 제54권4호
• /
• pp.252-257
• /
• 2011

농업 환경 중에 과잉으로 축적한 질산이온의 제거를 위하여, 질산이온 흡수력이 우수한 Enterobacter amnigenus GG0461 균주를 분리하였다. 이 균주는 Pseudomonas agar F (PAF) 배지에 배양하였을 때, 3,000 ppm (50 mM) 이상의 질산이온 흡수가 가능하므로, 농업용 토양, 축산폐수, 산업폐수를 포함한 오염된 환경의 질산이온 제거를 위한 좋은 후보 균주가 될 수 있다. GG0461 균주의 대량생산을 위한 상업용 배지를 개발하기 위하여 PAF 배지 성분을 상업용 재료로 대체하고, 균주의 성장과 질산이온 흡수 활력을 측정하였다. 탄소원인 글리세롤은 상업용 제품으로 대체하였고, 질소원으로 tryptone과 효모추출물, 대두박, 생선발효액을 배양실험에 사용하였다. 균주의 성장과 질산이온 흡수활력은 2% tryptone을 첨가한 배지에서 가장 우수하였고, 효모추출물, 대두박, 생선발효액의 순으로 효과가 나타났다. Tryptone을 2% 첨가한 배지에서 균주의 질산이온 흡수는 배지의 pH를 낮추었으며, 이것은 질산이온의 흡수가 nitrate/proton antiporter의 활성으로 나타남을 의미한다. 이상의 결과에서 상업용 tryptone을 사용한 배지는 균주의 생리활성에 적합하였으며, peptone을 제외한 PAF 배지의 각 성분은 그것에 해당하는 상업용 재료로 대체할 수 있었다. 결론적으로, GG0461 균주의 배양을 위한 상업용 배지성분 조성은 2% tryptone과 1% glycerol, PAF 배지를 위한 무기이온들로 결정하였다.

• 한국버섯학회지
• /
• 제6권3_4호
• /
• pp.115-120
• /
• 2008

야생에서 수집한 균주를 이용하여 우량 단핵계통을 선발하고, 선발한 단핵주를 이용하여 교잡을 통하여 새로운 품종 '갈뫼' 를 육성하였다. 갈뫼 품종은 균사배양 최적온도는 $25^{\circ}C$, 자실체발생 적온은 $14^{\circ}C$, 생육온도는 $7{\sim}180^{\circ}C$이었다. 갈뫼 자실체의 갓색깔은 갈색이며, 대기부는 진갈색으로 전형적인 야생팽이의 특성을 가셨고, 갓표면에 다소의 점성이 있었다. 갈뫼는 갈색 다수성 품종으로 발이가 고르고, 대가 곧고 강하며, 갓은 반반구형으로 생산력이 안정적이었다. 또한 갈뫼는 조리시 백색팽이 보다 씹는 저작감이 우수하므로 이를 홍보에 적극 이용할 필요가 있다.

• 대한수의학회지
• /
• 제49권2호
• /
• pp.127-133
• /
• 2009

Salmonella enterica subsp. enterica serovar gallinarum (S. gallinarum) is the agent of fowl typhoid, and the 9R vaccine is a commercial live vaccine for the prevention of fowl typhoid. The aim of this study was to assess the safety and immunogenicity of different brands of S. gallinarum 9R vaccine used in commercial laying chickens in Korea. All 9R strains originated from three different brands showed the same pattern in the biochemical and serological properties, and pulsed field gel electrophoresis (PFGE) profile. But, there was a difference in rhamnose fermentaion, agglutination with Salmonella group $D_1$ antiserum and PFGE pattern between 9R vaccine strain and field S. gallinarum isolates. In laboratory and field trials for assesment of safety and immunogenicity of 9R vaccine, all of the three 9R vaccines showed the same safety in commercial laying chickens. In addition, there was a significant difference between the vaccinated and unvaccinated control groups in mortality and the re-isolation rate of the challenge strain from the tissues (p < 0.05), and no difference by the brands of 9R vaccine. The results from this study indicated that all three different brands of S. gallinarum 9R vaccine showed highly protection against mortality and organ invasion in commercial laying chickens exposed to virulent strains of S. gallinarum.

• 한국해양공학회지
• /
• 제28권1호
• /
• pp.34-46
• /
• 2014

This paper discusses a new formulation for the failure strain in the average stress triaxiaility domain for a low-temperature high-strength steel (EH36). The new formula available at a low average stress triaxiality zone is proposed based on the comparison of two results from tensile tests of flat type specimens and their numerical simulations. In order to confirm the validity of the failure strain formulation, a user-subroutine was developed using Abaqus/Explicit, which is known to be one of the most popular commercial finite element analysis codes. Numerical fracture simulations with the user-subroutine were conducted for all the tensile tests. A comparison of the engineering stress-strain curves and engineering failure strain obtained from the numerical simulation with the user-subroutine for the tensile tests revealed that the newly developed user-subroutine effectively predicts the initiation of failure.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 1999년도 춘계학술대회논문집
• /
• pp.131.1-134
• /
• 1999

The effect of dynamic recrystallization during hot forming process was implemented to a commercial FEM code by conditioned remeshing and remapping of sate variables. A datum strain for stress compensation was determined as a strain for maximum softening rate and was able to be formulated as a function of critical strain f($\varepsilon$). The validity of remapping criterion was examined by a series of mechanical tests and microstructural observation. The application of suggested datum resulted in better estimation of load-stroke during forging processes.