• Korean Journal of Poultry Science
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• v.30 no.2
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• pp.73-81
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• 2003

This experiment was conducted to investigate the effects of dietary energy and protein levels on the growth rate of egg breeder pullets. A total of 360 Hy-Line Brown pullets aged 2 to 6 weeks (Phase I) were fed 5 rations differing in dietary protein (17, 19 and 20%) and energy (2,800, 2,950 and 3,050 kcal/kg, TMEn) leveIs for a period of 5 weeks and those aged 6 to 10 weeks (Phase II) were fed 5 rations differing in dietary protein (15, 16 and 17%) and energy (2,800, 2,900 and 3,000 kcal/kg, TMEn) levels in order to evaluate the optimum dietary energy and protein leveIs for egg breeder pullets reared in cages. Their body weight gains were significantly influenced by the dietary protein levels (P<0.05). The dietary energy levels did not greatly affect the growth performances throughout the experimental period. The low energy and protein regimen based on NRC requirement (control) was found to produce smaller pullets and lower tibia bone measurements as compared to the higher regimen groups. With the increase in dietary energy and protein levels, tibial bone strength and ash content also gradually increased (P<0.05). There were no significant differences in the flock uniformity among the treatments. These results indicate that increases in dietary energy and protein levels above the NRC requirements appeared to be more effective in obtaining the optimal growth and bone developments of egg breeder pullets reared in cage.

• Journal of Korean Society of Forest Science
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• v.79 no.2
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• pp.138-143
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• 1990

In mature stand of Japanese larch (Larix leptolepis(S. et Z.) Gordon) planted in 1925, heartrot damage was investigated by felling some infected trees with fruit bodies of two butt-rot fungi, Phaeolus schweinitzii and Sparassis crispa. Percentage of heartrot area on basal area of decay trees was 19.2-74.4, and the height reached by the decay was 1.2-5.5m. Percentage of decay volume was in the range of 2.2-13.4%, but the loss wood to the height reached by the decay amounted to 27.2% (range 13.1-37.1%) of whole volume, Decay damage caused by S. crispa was much greater than that caused by P. schweinitzii. Compressive strength ($52-77kg/cm^2$) and specific gravity (0.40-0.47) of rot wood was reduced to 77% and 39% respectively in maximum as compared to sound wood of healthy tree, and those of sound-looking wood close by heartrot to 42% and 26%. The current annual growth of trees with decay was fallen behind that of sound tree from eight to fourteen years after planting in D. B. H. and from twelve to twenty-one years after in volume.

• Journal of Korean Society of Steel Construction
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• v.26 no.6
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• pp.581-594
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• 2014

In this paper, flexural resistance of hybrid girder under uniform bending moment was evaluated, which is composed of HSB800 and HSB600 steel for the flange and web, respectively. Doubly-symmetric and monosymmetric sections with noncompact or compact flange and slender, noncompact or compact web were considered. Nonlinear analyses with 3-dim. shell element model were performed to determine the 'flexural resistance of section' and the 'lateral torsional buckling strength' by taking initial imperfection and residual stress into account. The numerical results were compared with the AASHTO LRFD and Eurocode 3 specifications and also the applicability of AASHTO LRFD appendix A6 was examined for the sections with noncompact and compact web.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6A
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• pp.399-409
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• 2012

The flexural behavior of HSB plate girder with a non-slender web, due to inelastic lateral-torsional buckling, under uniform bending was investigated by the nonlinear finite element analysis. Both homogeneous sections fabricated from SM570-TMC, HSB600 or HSB800 steel and hybrid sections with HSB800 flanges and SM570-TMC web were considered. The flanges and web of selected noncomposite I-girders were modeled as thin shell elements and the geometrical and material nonlinear finite element analysis was performed by the ABAQUS program. The steel was assumed as an elasto-plastic strain hardening material. Initial imperfections and residual stresses were taken into account and their effects on the inelastic lateral-torsional buckling behavior were analyzed. The flexural strengths of selected sections obtained by the finite element analysis were compared with the nominal flexural strengths from KHBDC LSD, AASHTO LRFD, and Eurocode and the applicability of these codes in predicting the inelastic lateral torsional buckling strength of HSB plate girders with a non-slender web was assessed.

• Journal of Korean Society of Steel Construction
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• v.28 no.4
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• pp.213-222
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• 2016

For a steel structure with long service period, structural performance can be changed or decreased by corrosion damage occurred under severe corrosion environment condition. In this study, to examine compressive strength and behavior of circular steel member depending on corrosion damage, compressive loading tests were conducted using circular steel member with artificial corrosion damage which was applied by mechanical process and hand drill. From test results, local corrosion area and pattern is related to their structural performance. Their lcoal bucklings were occurred near artificially sectional damaged part. Reduction in compressive strength of circular steel member was also suggested according to their corroded part and damage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1032-1038
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• 2003

The two-level full factorial and mixture design were used to screen ingredient type and to investigate the effects of ingredients on properties of surimi gel from jack mackerel using measurements of breaking forces, deformation values and color. The addition of starch decreased breaking force significantly (p<0.05), but did not affect deformation. The bovine plasma protein (BPP) among non-muscle proteins increased a breaking force and deformation value. However, the dried egg white increased slightly a breaking force, and decreased greatly a deformation value. The breaking force of gel was increased, but deformation value did not change significantly (p<0.05) with adding BPP. The whiteness of gel was slightly improved with the addition of corn starch and BPP. At 78% moisture, the optimum ratios of ingredients were 89.5∼90.0% for alkali surimi, 4.6∼6.0% for corn starch and 4.3∼5.4% for BPP to obtain above 110g for a breaking force, 4.2 mm for a deformation, and 22.5 for a whiteness.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.3
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• pp.37-41
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• 2016

In this paper, we introduced a near infrared fluorescence imaging system that has long working distance and analyzed on the effects of measurement variables such as gain, exposure time, working distance, magnification. Fluorescence signal intensity is growing up according to exposure time and magnification increasing, and it is getting stronger according to increase of gain, but the background signal intensity is getting stronger together. It causes low SBR. Due to a laser irradiation method, laser intensity distribution of the introduced system is not uniform and it makes fluorescence signal weak. So, we proposed a solution.

• Journal of Korean Society of Steel Construction
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• v.25 no.2
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• pp.141-151
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• 2013

In this paper, lateral-torsional buckling(LTB) strength of HSB800 steel plate girder under uniform bending moment was estimated by the nonlinear analysis. Doubly symmetric sections with slender, noncompact and compact webs were considered and the LTB strength in the inelastic range was estimated by taking initial imperfection and residual stress into account. For the numerical analysis, single-panel model and three-panel model were considered and analysis of SM490 steel plate girder was performed to judge the validity of the constructed models by comparing the results with AASHTO, AISC, Eurocode and KHBDC(LSD) codes. By using the same models, LTB strength of HSB800 girder was evaluated and it was acknowledged that the current codes can be applied to HSB800 girders with doubly symmetric section in the inelastic LTB range.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.495-501
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• 2006

This study was conducted to investigate the effects of thinning on soil properties and seed productivity in the 25-year-old Cryptomeria japonica and 30-year-old Chamaecyparis obtusa seed orchards in which thinning had been performed 4 years prior to the study. To this end, soil properties, cone and seed characteristics, seed production (kg/ha), and nutrient contents in seeds and cones were studied by 4 different thinning intensities (0, 20, 40, and 60%). Soil properties were not significantly different between the two orchards. Meanwhile, electric conductivity, total nitrogen, and $K^+$ concentration in the soil of C. obtusa seed orchard were significantly different among 4 different thinning intensities (p<0.05), while only $Ca^{2+}$ concentration in the C. japonica seed orchard was different (p<0.05). In the C. obtusa seed orchard, cone productivity increased with the increase of thinning intensities (p<0.05), whereas that in the C. japonica seed orchard did not show any significant differences. Both of the two seed orchards showed a tendency that seeds become bigger and heavier with the increase of thinning intensities, but any significant differences were not found. Seed production (kg/ha) in the C. obtusa seed orchard significantly increased with the increase of thinning intensities, while that of the C. japonica seed orchard decreased. Nutrient contents in seeds and cones did not show any significant differences among different thinning intensities in both of the two seed orchards.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.141.1-141.1
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• 2015

탄소나노튜브는 우수한 전기적 특성과 더불어 열전도도, 강도, 높은 화학적 안정성, 바이오 물질과의 친화성 때문에 많은 응용이 가능하며 최근까지도 활발히 연구되는 대표적인 탄소질의 물질이다. 이러한 다중 벽 탄소나노튜브를 제품화시키기 위해서는 특정 용매에서 용이한 분산성을 지닐 수 있도록 기능화 공정이 필수적이고 많은 양의 파우더를 기능화 시킬 수 있는 장비의 구조 및 공정개선이 요구된다. 플라즈마 기술을 이용한 건식의 순환형 나노분산 파우더 플라즈마 반복처리장치를 통하여 기능화 처리된 탄소나노튜브를 습식공정에 비해 간편한 공정으로 재현성 있고 균일한 결과로 많은 양의 확보가 가능하다. 이에 탄소나노튜브의 기능화 결과를 제시함으로써 본 장비를 소개하고자 한다.