Simplified Effective Compressive Strengths of Columns with Intervening Floor Slabs

Seung?Ho Choi,Jin?Ha Hwang,Sun?Jin Han,Hae?Chang Cho,Jae Hyun Kim,Kang Su Kim 한국콘크리트학회 2020 International Journal of Concrete Structures and M Vol.14 No.5

The current design codes discuss the effective compressive strengths of columns, which reflect a decrease in load transfer performance that can occur when columns and slabs have different concrete compressive strengths. The effective compressive strength of a column increases as it is confined by the slab, and the design codes mandate three different effective compressive strengths for interior columns (confinement on four sides), exterior columns (confinement on three sides), and corner columns (confinement on two sides). For both corner and exterior columns, the confinement effect of the slab is significantly smaller than that for the interior column, and there is a more marked decrease in load transfer performance. However, there is still a lack of theoretical studies investigating the effective compressive strengths of the corner and exterior columns. Therefore, based on the analysis model established in previous research, this study has proposed an equation for calculating the effective compressive strengths of the corner, exterior and isolated columns without any confinement effects of the slab. In addition, axial loading tests of isolated columns were conducted and the proposed equation was verified.

Anti‑inflammatory effect of Rosa laevigata extract on in vitro and in vivo model of allergic asthma via the suppression of IgE and related cytokines

Seung‑Hyeon Lee,Seung‑Han Choi,In‑Seung Lee,Yumi Kim,Eun‑Jin An,Hyeung‑Jin Jang 대한독성 유전단백체 학회 2020 Molecular & cellular toxicology Vol.16 No.2

Backgrounds Exposure to a toxic stress environment leads to excessive inflammatory reactions and induces allergic asthma resulting in airway hyper-responsiveness. We investigated whether Rosa laevigata Michx. (RL) exhibits anti-inflammatory effects related allergic asthma in both an in vitro and in vivo studies. Methods To investigate the preventive effect of RL, A549 cells were pretreated with non-toxic doses of RL (500, 1000 μg/ mL) and induced by epidermal growth factor (EGF) (10 ng/mL). First, we evaluated cytotoxicity via a MTT assay. The inhibitory effects of NF-κB activity and COX-2 expression were confirmed by a western blot assay. In the in vivo study, BALB/c mice were challenged with regard to ovalbumin via an intraperitoneal injection of RL (50, 100 mg/kg) and were killed to collect bronchoalveolar lavage fluid, lung tissues and blood serum. The number of inflammatory cells, the secretion of IgE and related cytokines were monitored by ELISA and multiplex assays. Results RL significantly suppressed NF-κB activity and COX-2 expression levels in EGF-induced A549 cells. In a chronic inflammation mice model, pretreatment of RL attenuated allergic airway inflammation by reducing inflammatory cells, the secretion of IgE and related cytokines in a dose-dependent manner. Conclusions The results of this study present the possibility of RL as a therapeutic agent for allergic asthma patients via the suppression of IgE and related cytokines.

디지털카메라를 이용한 3차원 측량 기법 개발에 관한 연구

崔哲淳,崔勝弼,韓元浩,金東熙 관동대학교 1997 關大論文集 Vol.25 No.2

Photographic survey is possible that it can survey the simultaneous three-dimensional survey about so many points, therefore it is so fast and precisely. We takes a snap the objects with digital carema, and input the data to the computer from this data. We can take the three-dimensional coordinate through relative orientation, absolute orientation and have to check the merit of three-dimensional suveying. Otherwise we can get the error in one centimeter after analysis three-dimension coordinate and we can get the higher precise accuracy cause to set the camera angle of 20∼45 degrees.

YIG Ferrite계의 결정구조 연구

최승한 慶山大學校 基礎科學硏究所 2000 基礎科學 Vol.4 No.2

Yttruim iron garnet(YIG)인 Y₃Fe_5O_12에서 Yttruim 이온을 다양한 금속으로 치환시킨 Y_3-xFe_5+xO_12(x=0.0, 0.18, 0.33, 0.6), Y_3-xIn_xFe_5O_12(x=0.0, 0.18, 0.33, 0.6), Y_3-xGd_xIn_0.2Fe_4.8O_12(x=0.2, 0.4, 0.6)의 결정구조 및 결정학적 특성을 X-선 회절법을 통해 연구하였다. 실온에서 측정된 X-선 회절상을 분석한 결과 전체 조성비 영역에서 단일상의 garnet 구조를 가지며 Y_3-xFe_5+xO_12에서는 전반적으로 치환량이 증가함에 따라 격자상수가 감소하는 경향을 나타냈다. 그러나 Y_3-xGd_xIn_0.2Fe_4.8O_12와 Y_3-xIn_xFe_5O_12계에서는 치환량 증가에 따라 격자상수가 증가함을 알 수 있었다. 격자상수값들이 조성비가 증가함에 따라 선형적으로 변화된 것은 치환된 이온의 반경에 따른 것이며 Vegard's law로 인해 나타나는 결과로 해석할 수 있었다. The substituted yttrium iron garnet systems Y_3-xFe_5+xO_12(x=0.0, 0.18, 0.33, 0.6), Y_3-xIn_xFe_5O_12(x=0.0, 0.18, 0.33, 0.6), Y_3-xGd_xIn_0.2Fe_4.8O_12(x=0.2, 0.4, 0.6) have been investigated by means of X-ray diffraction method. The X-ray diffraction patterns at room temperature confirm the samples to have a single phase of the garnet structure over the whole composition range. The lattice constants of all the sample linearly change with increasing x due to the size of substituted ions in the dodecahedral sites, which is attributed to Vegard's law.

한우 광역브랜드 사업전략

한성일,최승철 한국농업정책학회, 한국축산경영학회 2003 농업경영정책연구 Vol.30 No.3

Consumers are demanding for good quality and safety fresh-meat. Books of brand management are popularized, but not of Hanwoo brand cases. Case studies have a long history as effective tools to business person and as an interesting way to learn how to apply analytical tools in true-to-life agri-business. This study deals with three cases of regional Hanwoo brand initiative and derives the strategy of region-level business. Regional Hanwoo brand to succeed has several tasks and solutions such as marketing mind of consumer sovereignty, management of brand product, administration of blood lines and recording-keeping, joint efforts with other all related institutions, and long-run consumer research and systematic backup.

A study on magnetic structure of (Fe_(2)O_(2))-(Al_(2)O_(2))_(0.8-x)-(Ga_(2)O_(3))x-(SiO)_(0.2) by Mo¨ssbauer spectroscopy

최승한 慶山大學校 1998 論文集 Vol.16 No.1

뫼스바우어 분광법에 의해 산화물(Fe_(2)0_(3))-(Al_(2)0_(3))o.8-x-(Ga_(2)0_(3))x-(Si0)o.₂계에 관한 연구가 수행되었다. 상온에서의 뫼스바우어 스펙트럼은 x=0.2 경우 잘 정렬된 두 개의 Zeeman 형태로 나타났으나 0.4 x 1.0의 조성영역에서는 강한 이중선과 두 개의 Zeeman 형태가 중첩되고 2.0 x 4.0 에서는 이중선 만이 관측되었다. 중앙 이중선의 출현은 상자성 clustering에 의해 발생된 것으로 나타났다. 이성질체 이동값은 철 금속 foil에 대한 상대적인 값으로 얻어졌으며 이로부터 철은 +3가 상태이며 조성비에 따른 변화는 작음을 알 수 있었다. 또한 사중극자분열값은 거의 영에 가까운 값을 보였으며 이중선의 비대칭성은 결정의 임의 방향성에 의한 것으로 나타났다. The magnetic oxide system (Fe₂0₃)-(Al₂0₃)o.8-x-(Ga₂0₃)x-(Si0)o.₂ has been investigated by means of M ssbauer spectroscopy. The M ssbauer spectrum at room temperature for x=0.2 shows well defined two Zeeman patterns but the spectra for 0.4 x 1.0 exhibit the superposition of two Zeeman patterns and a strong doublet also and the spectra for 2.0 x 4.0 show only doublet. The central line (doublet) in this system suggests that super paramagnetic behavior is caused by super paramagnetic clustering. Isomer shifts are obtained relative to natural iron-foil, It shows that Feions of this system exist in the high spin Fe³+ state. The dependence of isomer shift on x is small. The Quadrupole splittings values are near the zero. Asymmetry of doublet is caused by the preferred orientation of crystallities.

가변부하를 이용한 PV모듈의 시험회로 설계

최연옥,이열선,서진연,한승조,조금배 조선대학교 동력자원연구소 1997 動力資源硏究所誌 Vol.19 No.1

A complete computerized system for the characterization and performance testing of photovoltaics(PV) modules under natural sunlight and ambient condition was designed. I-V characteristics of PV module provides on essential diagnostic means in assessing the performance and internal cell parameters of PV module depends on its basic materials, manufacturing technology and operating environmental conditions. I-V curves derived from PV modules refect to a large extent the physical properties and their expected performance. In this paper, Electrical performance measurement and evaluation methods for solar cell module by MOSFET variable Load were studied. Also, Mathematical model and theory of solar cell associated with the photovoltaic effect has been discribed.

(Fe_(2)O_(3))_(5)-(Al_(2)O_(3))_(3.4)-(Ga_(2)O_(3))_(0.6)-(SiO)의 결정구조 및 자기적 특성연구

최승한 慶山大學校 2000 論文集 Vol.18 No.1

The crystal structure and magnetic properties of Ga_(2)O_(3) substituted ferrite (Fe_(2)O_(3))_(5)-(Al_(2)O_(3))_(3.4)-(Ga_(2)O_(3))_(0.6)-(SiO) has been studied using X-ray diffraction method and M ssbauer spectroscopy. The M ssbauer spectrum at room temperature shows the superpositions of two Zeeman patterns and a strong doublet. The doublet seems to be originated from the superparamagnetic clusters, It shows significant departures from the Neel's collinear model and seems to be the diluted ferrites. The M ssbauer spectra below R.T show various and complicated patterns, which can be explained by freezing of the superparamagnetic clusters. On cooling, magnetic states of the system may be various and multicritical.

남은음식물 비육우 사료자원화 분석

한성일,최승철 한국농업정책학회, 한국축산경영학회 2001 농업경영정책연구 Vol.28 No.3

This study focuses on the use of food residual feed, particularly the use on beef production. To analyze economic performance of the use, farmers were separated into and surveyed by two groups: food residual feeding group (group A) and common feed feeding group(group B) in Southern Yangju-Gun. Results show that farmer group A has lower feed costs only by 60% than that of group B, representing a cost advantage.

다단식 이중관기포탑내의 기액간 물질전달

한승완,최일곤,김상렬 동아대학교 공과대학부설 생산기술연구소 1997 生産技術硏究所硏究論文集 Vol.2 No.1

The effect of gas houdup and volumetric liquid-phase mass transfer coeffecient in the bubble coplumn with multiple draft tube were investigated experimentally, according to gas velocity, plate interval and the diameter and plate number of draft tube at 298±0.5K. The gas holdup and volumtric liquid-phase mass transfer coeffecient increased with decreasing the interval of draft tube when the diameter ratio of draft was small but decreased when the diameter ratio of draft tube was large. Also based on these observations, correlation equations of gas holdup and volumetric liquid phase mass transfer coefficients were proposed.