• Journal of Korean Society of Steel Construction
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• v.9 no.2 s.31
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• pp.171-179
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• 1997

The high-tension bolted joints are clamped by the axial force which approaches the yielding strength. The introduced axial force is transmitted to the connection members pass through washer. The transferred load in connections is balanced to the compressive stress of plates, axial force in bolts and the external loads. In this mechanism, the compressive stress and slip load we dominated by the effective stiffness of bolted joints and plates. In general the effective stiffness is specified to product to the effective area and elasticity modulus in connections. In this reason, the conic projection formular which is assumed that the axial force in bolts is distributed to the cone shape and that region is related to the elastic deformation mechanism in connections, was proposed. But it conclude what kind of formula is justified. Therefore in this paper, the fatigue tests are performed to the high tension bolted joints and inspected to the phase on the friction face. And using the FEM and numerical method, it is analyzed and approximated to the compressive stress distribution and its region. Moreover, it is estimated to the effective area and to the relation the friction area to the effective compressive distribution region.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.276-286
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• 2013

The goal of this study was to investigate change of thermal decomposition feature of miscanthus (Miscanthus sacchariflorus) after removal of inorganic constituents using distilled water (D.I-w; 30, 60 and $90^{\circ}C$). The carbon content was increased whereas the oxygen content was decreased with the temperature of D.I-w treatment. Moreover, ash content was slightly decreased from 4.6% of control to 3.2% of $90^{\circ}C$ D.I-w treated sample. Results of total monomeric sugar contents and X-ray diffraction (XRD) analysis showed that structural changes of cellulose/hemicellulose regions did not occurr during D.I-w treatment. Results of inductively coupled plasma emission spectrometer (ICP-ES) showed that miscanthus has the largest amount of inorganic constituents such as potassium (5,644 ppm), phosphorus (3,995 ppm), magnesium (1,403 ppm) and calcium (711 ppm). Thermogravimetric analysis (TGA) confirmed that the yield of char slightly decreased whereas the yield of volatiles increased with increasing D.I-w treatment temperature. In addition, differential thermogravimetric analysis (DTGA) indicated that the maximum decomposition rate ($V_M$) and temperature ($T_M$) corresponding to VM were varied from $0.82%/^{\circ}C$, $360.60^{\circ}C$ of control to $1.17%/^{\circ}C$, $362.62^{\circ}C$ of $90^{\circ}C$-D.I-w treated sample.

• Journal of Chest Surgery
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• v.31 no.8
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• pp.763-769
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• 1998

Background: Supravalvular aortic stenosis is a rare form of congenital cardiac anomaly involving ascending aorta distal to coronary orifice. Materials and methods: We operated 12 cases of supravalvular aortic stenosis between July 1986 and March 1997. Age ranged from 4 to 17(mean 10.2) years and 11 of them were male. Nine patients had clinical features of Williams syndrome. We experienced two types of supravalvular aortic stenosis, including 10 hour glass type and 2 diffuse type. Results: Preoperative transaortic pressure gradient ranged from 40 to 180(mean 92) mmHg by cardiac catheterization. Pulmonary stenosis was associated in 5 and 2 of them required angioplasty. Operative techniques included 6 standard aortoplasty with elliptical patch, 4 extended aortoplasty with inverted Y shaped patch, and 2 modified Brom's repair. There were no operative deaths. Postoperative echocardiographic evaluation was done at a mean interval of 12 months. Grade I or II aortic regurgitation was found in 3 cases. Postoperative cardiac catheterization revealed a mean transaortic pressure gradient of 26 (range 0 to 75) mmHg. A mean pressure drop was 78(range 30 to 114) mmHg. All patients were followed up for a mean of 40(range 1 to 67) months with uneventful clinical course. Conclusions: Our data proved the low mortality and excellent hemodynamic improvement after surgical relief of supravalvular aortic stenosis in children.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.10a
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• pp.153-156
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• 1996

현재의 정보시스템이 하드웨어의 발전에 비해 늦어진 이유는 개발 단계별로 상호 일관성이 결여된 방법론을 사용하고 있고 이 방법론들이 실제의 비즈니스 프로세스(Business Process)와는 차이가 있는 형태로 구현이 되기 때문이다. 또한, 이런 방법론들이 분산조직에 사용된다면 비즈니스 프로세스가 세분화되기 때문에 문제점들이 더 깊이 심화되는 경향이 발생하게 된다. 이런 상황에 대한 해결책은 정보시스템이 비즈니스 프로세스로부터 구체적인 정보시스템의 구현에 이르기까지 일관성 있게 진행할 수 있는 방법론이 필요하다. 그러므로, 정보시스템 구현의 각 단계별로 추상과 구현방법을 구체적으로 제시하고 개념적인 무결성을 보장할수 있는 새로운 정보시스템 개발방법이 요구된다. 본 논문에서는 이러한 정보시스템을 구현하기 위해서 업무분석의 과정에서부터 구현에 이르기까지 개념적인 무결성(Conceptual Integrity)을 유지하고(Brooks, 1982) 방법론상에서 중단이나 변형없이 연결되는 시스템 개발방법론인 컴퓨터 통합 비즈니스 시스템(Computer-Integrated Business System:CIBS)을 소개하고 이 CIBS가 사용하는 세부적인 객체지향 프로그래밍 방법론이 AF(Application Framework)을 설명하며, 최종적으로 이 CIBS에 의해서 구현된 정보시스템과 기존의 프로그래밍 기법으로 구현된 정보시스템과의 비교를 통해 그 장단점을 증명하고자 한다. 또한, 이 CIBS구조는 정보시스템의 단편적인 정보제공 능력을 넘어서서 비즈니스 프로세스를 개선함에 의해서 기업의 노하우를 정립하고 이를 발전시키는 정보시스템의 진보된 형태를 보여줌으로서 정보시스템의 새로운 모습과 비젼을 제시하며 혁신적인 정보시스템의 새로운 구조를 보여준다. 문제점들은 HED (Human Engineerign Discrepance) 목록으로 정리하여 설계에 반영하도록 하였다.로 마음의 안정감, 몸의 긴장 이완에 따른 건강 상태 유지, 수업 집중도 향상 등이 나타났다. 위와 같은 종합 적 분석 결과에 따라, 본 연구는 제조 현장의 생산성 향상 및 품질 향상과 연계하여 작업자의 작업 집중도 향상, 작업자의 육체적, 심리적 변화에 따른 생산성 및 품질 향상 변화 정도 등의 산업공학(인간공학) 제 분야의 여러 측면에서 연구 및 적용이 가능하리라 사료된다.l, 시험군:25.90$\pm$7.16mg/d1, 47% 감소)를 나타내었으며, 시험군의 AUC는 대조군에 비해 39% 감소하였고, 혈중 아세트알데히드의 농도는 투여 60분후 시험군(3.96$\pm$0.07nmo1/$m\ell$)이 대조군(6.45$\pm$0,64nmo1/$m\ell$)에 비해 유의성 있는 감소(39%)를 나타내었으며, 시험군의 AUC는 대조군에 비해 48% 감소하였다 한편, 시험관내 에탄올 대사 효소에 대한 바이오짐의 효과를 검색해본 결과 바이오짐(2.0 $\mu\textrm{g}$/assay)에 의해 Aldehyde dehydrogenase(1.5unit/assay)의 활성이 14% 증가되었다. 본 연구의 결과로 볼 때, 비지니스 및 바이오짐은 음주 후 상승된 혈중 에탄을 농도 및 아세트알데히드의 농도를 현저히 감소시키는 효과가 있었다.량 보호 관리, 도시 소공원 개발, 역사 문화 공원 조성, 하천 공간 복원, 공원 시설 기능 개선, 이용 프로그램 개발, 공원 관리 개선, 환경 피해 녹지의 회복, 도시 환경 림 조성, 녹지 기능

• The Korean Journal of Pain
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• v.18 no.2
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• pp.204-207
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• 2005

Background: Transpedicular percutaneous vertebroplasty, along with kyphoplasty of the thoracic vertebrae, is technically more difficult than those of the lumbar vertebrae due to the anatomical differences. During the last four years, all the percutaneous vertebroplasty and kyphoplasty of the thoracic vertebrae carried out at our institution were performed using a transpedicular approach; therefore, we tried to find if there were any problems or complications associated with the process. Methods: The medical records of all the patients who had undergone thoracic percutaneous vertebroplasty or kyphoplasty were retrospectively reviewed. The following were looked up: the procedure name, unipedicular or bipedicular, the level of the thoracic vertebrae treated, and the pre- and postoperative changes in the Visual Analog Scales (VAS), the volume of cement injected and complications. Results: In the last four years, 58 vertebral bodies in 58 patients were treated. Twelve and 46 vertebral bodies were treated by kyphoplasty and vertebroplasty, respectively. A total of 58 mid and lower thoracic levels were treated: T5 (n=1), T6 (n=1), T7 (n=3), T8 (n=4), T9 (n=1), T10 (n=4), T11 (n=14) and T12 (n=30). The mean preoperative and postoperative VAS scores were $8.1{\pm}1.4$ and $5.2{\pm}1.7$, respectively. The mean volume of cement injected was $4.01{\pm}1.85ml$; $3.18{\pm}0.60ml$ at T5-8 and $4.22{\pm}2.27ml$ at T9-12. There were no clinical complications, such as pedicular fracture or cement leakage. Conclusions: Although transpedicular vertebroplasty and kyphoplasty at the mid to lower thoracic vertebral bodies is technically difficult compared to that at the lumbar region, the procedures can be performed safely.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.353-360
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• 2003

For the simple rapid bioassay of organophosphorus and carbamate pesticide residues, a mass-production system of acetycholinesterase (AChE, EC 3.1.1.7, MAChE) using baculovirus and insect cell culture was constructed. The cDNA for AChE was synthesized from Drosophila melanogaster in Halla Mountain, the lipid anchor tail was removed by PCR and was used for the site-directed mutagenesis of three amino acid residues (E107Y, F368L, L408F). The mutated cDNA was inserted into the baculovirus vector and expressed in insect cells. Maximum cell growth and enzyme activity were reached when the cells $(2{\times}10^6\;cell/ml)$ were infected four times at four-day-intervals. His-tag containing MAChE was purified using Ni-NTA column and used for characterization. The activity was maintained under various pHs (3-10) and temperatures $(20-50^{\circ}C)$ under experimental conditions. As an extraction solution for pesticides, methanol is more effective than ethanol. Against major organophosphate and carbamate pesticides, the MAChE showed better sensitivity than AChE and AChE from housefly (Taiwan).

• Applied Biological Chemistry
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• v.51 no.3
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• pp.188-193
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• 2008

This study was conducted to investigate the effect of moisture content and pressure on extraction yield, crude saponins and ginsenoside contents of puffed Korean ginseng. Puffed ginsengs showed relatively higher extraction yield ($50.0{\sim}62.1%$) and amounts of crude saponins ($19.6{\sim}48.8$ mg/g ginseng) than no-puffed ginseng ($37.6{\pm}0.8%$ and $11.0{\pm}1.0$ mg/g ginseng), respectively. The highest extraction yield and amounts of crude saponins were obtained in 8.0% moisture content sample puffed at 10 $kg_f/cm^2$. In HPLC analysis, amounts of measured major ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) decreased with increasing puffing pressure, yet contents of almost all major gin senosides were higher than control (no-puffed). On the other hand, ginsenoside Rg3 were produced after puffing suggesting that chemical structure of some ginsenosides might be altered during the puffing process. These results indicate that puffing can increase the extraction yield and crude saponin contents and it could influence the ginsenoside composition.

• Korean Journal of Animal Reproduction
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• v.18 no.2
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• pp.141-150
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• 1994

Morphological features of the interaction between the hatching blastocyst and implantation in pig were studied by electron microscopy. The observations extended from late blastocyst stage to the completion of trophoblastic erosion of the epithelium and early decidual transformation of the epithelium and early decidual transformation of the stromal cells. Between day 7 and 17 of pregnancy, blastocysts from 0.3 to 12 mm in diameter were flushed from the uterine horns of Dutch Landrace pigs. On the 7th of development in the pig blastocyst, the blastocyst shedded of the zona pellucida established the tips of microvilli and with bleb-like cytoplasmic protrusions of the epithelial cells. From day 11 on in pig embryo, the bilayered trophoblast undergoes a dramatic phase of elongation so that the initially spherical expanded blastocyst becomes tubular. In pig, close apposition to the uterine wall beg-ins at about 12 $^1$/$_2$ days and then attachment occurred during the afternoon of the 16th or 18th day post coitum. At this stage, embryonic loss compared with corpus luteum number is up to 40% of ovulated oocytes. Therefore, the implantation failture of these embryos may be mainly caused by morphological abnormality and failture of zona shedding.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.38-43
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• 2004

Effects of heat treatment on functional properties of soy protein were examined. Soy protein isolate (SPI) was prepared from Korean soybean varieties, Manli and Taekwang, subjected to heat treatment at $60^{\circ}C$ for 30, 60, 90, and 120 min. pH-solubility results of SPI showed typical U-shape profiles with minimum solubility at pH 4-5 of isoelectric points of soy proteins, longer heat treatments showing slightly higher solubility. Water absorption, emulsifying activity, emulsion stability, and emulsion capacity of SPI increased, while oil absorption decreased, with heating time in Manli variety. Manli and Taekwang showed the highest emulsion capacities after 90-and 60-min heat treatments, respectively. Foam expansion of all SPIs increased with heating time up to 90 min. Texture profile analysis showed heat treatment up to 90 min significantly increased hardness, adhesiveness, springiness, gumminess, and chewiness, whereas significantly decreased cohesiveness of SPI gels (p<0.05).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.424-429
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• 2018

In this study, an expansion joint that is susceptible to waterhammer was tested for its vibration durability. The operation data for the hydraulic actuator was the expansion length of the expansion joint when the waterhammer occurred. In the case of the vibration durability test, the internal temperature status of the expansion joint was assumed to be a stress factor and a lifespan prediction model was assumed to follow the Arrhenius model. A test was carried out by increasing the internal temperature status at $30^{\circ}C$, $50^{\circ}C$, and $65^{\circ}C$. By a linear transformation of the lifespan data for each temperature, a constant value and activation energy coefficient was induced for the Arrhenius equation and verified by comparing the value of a lifetime prediction model with the experimental value at $85^{\circ}C$. The failure modes of the ongoing or finished test were leakage, bellows separation, and internal deformation. In the future, a composite lifespan prediction model, including two more stress factors, will be developed.