• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.9
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• pp.1632-1642
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• 1992

When a blind hole of small diameter is drilled in the field of residual stress, strain relieved around the hole is function of magnitude of stress, patterns of stress distribution and hole geometry of diameter and depth. Relieved strain coefficients can be calculated from FEM analysis of relieved strain and actual stress. These relieved strain coefficients make it possible to measure residual stress which vary along the depth in the subsurface of stressed material. In this study, the calibration tests of residual stress measurement are carried out by drilling a hole incrementally on the cantilever or on the tensile test bar. Residual stresses can be determined from measured strains around a shallow hole by application of power series method. For the sake of reliable measurement of residual stress, much efforts should be done to measure relieved strains and hole depth more accurately comparing with conventional procedures of gage subject to the external load. Otherwise linear equations converting strains into stresses may yield erratic residual stresses because of ill-conditions of linear equations. With accurate measurements of relieved strains, residual stress even if varying along the depth can be measured. It is also possible to measure residual stress in the thin film of material by drilling a shallow hole.

• Korean journal of food and cookery science
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• v.29 no.4
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• pp.361-366
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• 2013

This research was performed to investigate the effect of Agarum cribrosum ethanol extracts on the levels of lipids in the serum of rats fed a high-fat diet for 10 weeks. Experimental groups were divided into basal diet only (BDG), high fat diet control (HFDCG), high-fat diet and 5% Agarum cribrosum ethanol extract powder (HF5S), and high-fat diet and 10% Agarum cribrosum ethanol extract powder(HF10S) groups. The levels of hematological variables were not significantly different among the four groups. Compared with the control group's serum total cholesterol level of 89.14 mg/dL, the levels of the HF5S and HF10S groups were significantly lowered to 77.26 and 75.47 mg/dL, respectively. Compared with the control group's LDL-cholesterol leve of 27.41 mg/dL, the LDL-cholesterol levels of the HF5S and HF10S groups were significantly lowered to 20.64 and 20.17 mg/dL, respectively. Also, compared to the control group's serum triglyceride level of 98.36 mg/dL, the triglyceride levels of the HF5S and HF10S groups were significantly lowered to 87.94 and 87.39 mg/dL, respectively. These results indicate that dietary intake of Agarum cribrosum ethanol extracts might have beneficial effects on obesity by reducing body weight and improving blood lipid profile.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.399-400
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• 2006

• Journal of Industrial Technology
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• v.8
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• pp.47-64
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• 1988

축의 지름이 구멍의 지름보다 큰 경우, 축을 구멍에 조립하는 작업이 용이 하도록 하는 방법을 연구하였다. 이 조립작업의 성능평가를 위한, 새로운 다중목적함수(多重目的函數)를 고안하고 그에 관련된 설계변수들의 최적값을 찾아보았다.

• 프린팅코리아
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• v.14 no.6
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• pp.93-93
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• 2014

우리가 잊고 있던 놀이의 기억을 끄집어내 재창조한 '좀 놀아본 캠핑'은 1년간 캠핑장에서 가족이 함께 놀아본 77가지 놀이를 보기만 해도 행복함이 전해지는 화보같은 사진으로 담아내 읽는 즐거움을 더해준다. (주)성우애드컴의 이민성 대표이사가 지난 4월 런칭한 출판브랜드 개미똥구멍을 통해 선보인 첫 작품이다.

• Venture DIGEST
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• s.76
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• pp.26-26
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• 2005

대한민국 젊은이들은 할 일이 너무 많다. 사춘기 때는 수험생이라는 이름으로 대학입시라는 바늘구멍을 통과하기에 바쁘고 졸업 후에는 청년실업 35만명 시대에 취업준비생이라는 이름으로 더 작은 바늘구멍을 통과해야 한다. 이런 문제를 해결해 보고자 나선 젊은 회사가 있으니, 경상대학교 대학생창업기업‘아이미루닷컴(대표 최성욱)’이 바로 그들이다.

• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.570-575
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• 2015

The green algae have cellulose as a main structural component of their cell wall and the cellulose content in green algae is much higher than other marine algae such as brown algae and red algae. Furthermore, green algae do not contain lignin in their cell wall and store starch as food in their plastids. Thus, it was investigated that the effect of hydrothermal pretreatment process utilizing microwave irradiation for Ulva pertusa Kjellman, a division of green algae, which is expected to be utilized for bioenergy production, on the enzymatic hydrolysis. The hydrothermal temperature have an effect on the pretreatment of Ulva pertusa Kjellman, but the effect of power of microwave irradiation is negligible. The rate of enzymatic hydrolysis was increased as the hydrothermal temperature increased until $140^{\circ}C$. The enzymatic hydrolysis of pretreated Ulva pertusa Kjellman under the optimum pretreatment conditions (50 W of microwave irradiation power and $150^{\circ}C$ of hydrothermal temperature) with cellulase, ${\alpha}$-amylase, and Novozyme 188 having ${\beta}$-glucosidase acitivity resulted in the saccharification of 96 wt% of total carbohydrate in Ulva pertusa Kjellman during 3 hrs, while it took 24 hrs for the enzymatic hydrolysis of untreated Ulva pertusa Kjellman. It confirmed that the hydrothermal pretreatment was effective on Ulva pertusa Kjellman for the enzymatic hydrolysis.

• Analytical Science and Technology
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• v.12 no.5
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• pp.360-369
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• 1999

In this research, a study of adsorption kinetics of heavy metal ions on the Ulva pertusa and Hizakia fusiformis which is aiming at removing metal ions from water or every kind has been carried out. During the process of this research. Adsorption kinetics of Cd(II) and Pb(II) ions by the Ulva pertusa and Hizakia fusiformis, within five minutes reached at the maximum adsorption amount. The adsorption amoum by Ulva pertusa was more than the other. Adsorption ratio by Ulva pertusa were 15.0~100% of Cd(II) and 39.2~82.5% of Pb(II). Adsorption ratio by the Hizakia fusiformis were 18.3~100% of Cd(II) and 56.4~94.7% of Pb(II). Additionally, recovery ratio or Cd(II) from the Ulva pertusa presents 75.0~83.6% and that of Pb(II) ions presents 79.1~85.5%. Also, recovery ratio of Cd(II) from Hizakia fusiformis fusiformis were 66.7~85.0% of Cd(II) ions and 77.6~83.9% of Pb(II) ions respectively. As a result of this research. adsorption amount of Cd(II) and Pb(II) ions by Ulva pertusa was more than it by Hizakia fusiformis.

• The Korean Journal of Pesticide Science
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• v.19 no.2
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• pp.106-112
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• 2015

This experiment was carried out to investigate the best spray timing for the control of the bacterial shot hole with Bordeaux mixture (6-6) after wintering in the peach orchard. We sprayed Bordeaux mixture (6-6) on 'Mibaekdo', 'Yumyeong' and 'Cheonhong' of peach verities from late-March to mid-April in 2001, 2002 and 2014, and examined how much bacterial shot hole and chemical injure occurred. The infection rate of bacterial shot hole according to spray time was 10.2 to 11.7% at leaves, and 1.7 to 2.2% at fruits in 2002. And Efficacy of the Bordeaux mixture treatment for control of bacterial shot hole at full blooming time 21.2 to 30.4% at leaves, 1.7 to 4.4% at fruits in 2014. The chemical injure occurred slightly for one week hence. The fruit bearing rate was 20.7 to 29.8% at 'Mibaekdo', and 35.4 to 61.9% at 'Yumyeong' peach trees. When the spray at the time of blooming period by bordeaux mixture was investigated the control effect of bacterial shot hole disease. The infected leaves was better than 21 to 25% twice the quantity of finished products and bordeaux self-preparation about 28 to 30% base quantity of finished products, also the control efficacy was higher in infected fruits trends in bordeaux self-preparation method and twice the quantity of finished products.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.2
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• pp.437-444
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• 2017

Stress concentrations around discontinuities, such as a hole in cross section of a structural member, have great importance because the most materials failure around the region may be occurred. Stress on the point applied by concentrated load reaches much larger value than the average stress in structural member. In this paper, stress analysis was performed for the plate with a partial through-hole to find the difference of the principal stress distribution. The difference between maximum principal stress and minimum principal stress in photoelasticity is equal to the value obtained by multiplying the isochromatic fringe order by the fringe constant of the material divided by the distance through which the light passes, that is, the thickness of the specimen. Since the difference of principal stress is proportional to the photoelastic fringe order, the distribution of the principal stress difference by the finite element analysis can be compared with the photoelasticity experimental result. ANSYS Workbench, that is the finite element software, is used to compute the differences of principal stresses at the specific points on the measured lines. The computation values obtained by ANSYS are compared with the experimental measurements by photoelasticity, and two results are comparable to each other. In addition, the stress concentration factor is obtained using the stress distribution analyzed from the variation of hole depth. Stress concentration factor is increasing, as the depth of hole increase.