• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3A
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• pp.421-428
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• 2006

This study was performed by using experiment to minimize behavior difference of Monolithic and segmental Girder and to prove the design concept of the PSI (Precast PSC-Segmental I Grider). A full scale girder test was performed in four different cases, the monolithic girder, the segmental girder type-1, the segmental girder type-2 and the segmental girder type-3. The monolithic girder that was produced in one body 25 m span and the segmental girder that was jointed 5-sliced 5 m segment. The girder was built by as one body prestressing the tendons after manufacturing the segmental girder, and second prestressing after the casting of the slab concrete. The test result shows that the measured values were almost same or slightly bigger than the theoretical values which means that the PSI girder bridges concept came out to be reliable.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.51-57
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• 2011

Purpose: The aim of this study is to identify clinical usefulness of Wide Beam Reconstruction (WBR) which is called Xpress.cardiac$^{TM}$ to confirm the agreement between segmental perfusion and regional wall motion in myocardium compared to conventional OSEM method. Materials and Methods: Subjects were separated two groups. First group was composed of 20 normal control group. Second group was composed of 10 patients (abnormal group) who had coronary artery disease. Subjects underwent myocardial perfusion SPECT ($^{201}Tl$ rest and $^{99m}Tc$-MIBI stress). Image acquisition and reconstruction were that rest stage was each step per 30, 15 seconds and stress stage was each step per 25, 13 seconds, OSEM and WBR methods were applied. Segmental perfusion and regional wall motion were applied 20-segment model of QPS, QGS algorithm in AutoQuant. Status of perfusion was composed of 5 point scoring system (0=normal, 1=mild, 2=moderate, 3=severe hypokinesia, 4=dyskinesia). Status of regional wall motion was also composed of 5 point scoring (0=normal, 1=mild, 2=moderate, 3=severe hypokinesia, 4=dyskinesia). We evaluated the agreement between conventional OSEM and WBR through automatic quantification value. Results: The agreement of rest segmental perfusion between conventional OSEM and WBR in normal patients was 99% (396/400, k=0.662, p<0.0001) and one of rest regional wall motion was 83.8% (335/400, k=0.283), the agreement of stress segmental perfusion was 95.8%(383/400, k=0.656), one of stress regional wall motion was 87.3% (349/400, k=0.390). The match rate of rest segmental perfusion in abnormal patients was 83% (166/200, k=0.605, p<0.0001) and one of rest regional wall motion was 55.5% (111/200, k=0.385), the agreement of stress segmental perfusion was 79.5% (159/200, k=0.682), one of stress regional wall motion was 63.5% (127/200, k=0.486). Conclusion: Compared to conventional OSEM, WBR method had a good agreement of segmental perfusion in myocardium in normal and abnormal groups. However regional wall motion showed meaningful low agreement. Although WBR offers high resolution and contrast ratio, it is not useful method for gated myocardial perfusion SPECT.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.4
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• pp.285-291
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• 2008

Purpose: Although automatic quantification software of myocardial perfusion SPECT provides highly objective and reproducible quantitative measurements, there is still some limitation in the direct use of quantitative measurements. In this study we derived parameters using normal variation of perfusion measurements, and tried to test the usefulness of these parameters. Materials and Methods: In order to calculate normal variation of perfusion measurements on myocardial perfusion SPECT, 55 patients (M:F = 28:27) of low-likelihood for coronary artery disease were enrolled and $^{201}TI$ rest/$^{99m}Tc$-MIBI stress SPECT studies were performed. Using 20-segment model, mean (m) and standard deviation (SD) of perfusion were calculated in each segment. As a myocardial viability assessment group, another 48 patients with known coronary artery disease, who underwent coronary artery bypass graft surgery (CABG) were enrolled. $^{201}TI$ rest/$^{99m}Tc$-MIBI stress / $^{201}TI$ 24-hr delayed SPECT was performed before CABG and SPECT was followed up 3 months after CABG. From the preoperative 24-hr delayed SPECT, $Q_{delay}$ (perfusion measurement), ${\Delta}_{delay}$ ($Q_{delay}$ - m) and $Z_{delay}$ (($Q_{delay}$ - m)/SD) were defined and diagnostic performances of them for myocardial viability were evaluated using area under curve (AUC) on receiver operating characteristic (ROC) curve analysis. Results: Segmental perfusion measurements showed considerable normal variations among segments. In men, the lowest segmental perfusion measurement was $51.8{\pm}6.5$ and the highest segmental perfusion was $87.0{\pm}5.9$, and they are $58.7{\pm}8.1$ and $87.3{\pm}6.0$, respectively in women. In the viability assessment $Q_{delay}$ showed AUC of 0.633, while those for ${\Delta}_{delay}$ and $Z_{delay}$ were 0.735 and 0.716, respectively. The AUCs of ${\Delta}_{delay}$ and $Z_{delay}$ were significantly higher than that of $Q_{delay}$ (p = 0.001 and 0.018, respectively). The diagnostic performance of ${\Delta}_{delay}$, which showed highest AUC, was 85% of sensitivity and 53% of specificity at the optimal cutoff of -24.7. Conclusion: On automatic quantification of myocardial perfusion SPECT, the normal variation of perfusion measurements were considerable among segments. In the viability assessment, the parameters considering normal variation showed better diagnostic performance than the direct perfusion measurement. This study suggests that consideration of normal variation is important in the analysis of measurements on quantitative myocardial perfusion SPECT.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.33-36
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• 2008

It is generally known that a shell in the form of layered structures stacked up thin elements by organic adhesives has high resistance capacity against static and impact loading. The complex materials such as these diversified layered structures are more reliable and efficient to the impact loading than the single material. In this study, the segmented composites in the shape of a beam were made, using mortar and concrete block and tested under static and impact loading in order to develop the complex materials in the form of layered structures as the segmented composites to resist impact loading. And it compared to the normal concrete beams having the same compressive strength to evaluate the differences in their performance and failure modes.

• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.479-486
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• 1998

Bimaxillary Protrusion can be treated effectively in growing patients and in adults with conventional orthodontic therapy. However, In the adult patient, combined surgical and orthodontic treatment modalities may offer distinct advantages over such conventional therapy. In those cases complicate by vertical jaw dysplasia, sagittal dysplasia, or transverse skeletal discrepancy in addition to bimaxillary protrusion, the possibilities of obtaining successful results through orthodontic treatment alone greatly diminish. Surgical retraction of both maxillary and mandibular anterior segments with subapical osteotomies and ostectomies in the extraction site may be a good treatment alternative. Treatment time and possible adverse effects of lengthy orthodontic therapy may be reduced and optimum esthetic improvement may be facilitated. On the following cases, patient who had bimaxillary protrusion with Angle class III malocclusion was treated with combined orthodontic - surgical therapy by anterior subapical segmental osteotomies.

• Lingua Humanitatis
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• v.1 no.2
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• pp.21-46
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• 2001

No one would deny that, despite the fact that they are the central factor in any given communication system, language signals have their limitations. For example, language cannot keep up with the radical changes that occur in the world and its ideas. The present meaning of a language signal is always pegged to the past when it was originally created. This limitation in turn puts limitations on the way we conceive of the world, and we have no choice but to watch the world through the refracted, darkly colored lens called language. Lee Sang′s was well aware of these limitations, and his works reflect his suspicion of language. This paper argues that Lee Sang′s "Ogamdo 1" is a poetic commentary on the ambiguity of language signals; that "Ogamdo 2" is an accusation of the stationary nature of language signals; ; and, finally, that "Sune-kwanhan-gakseo (Treatise on Lines) 7" is a poetic expression of Lee Sang′s negative view of the symbolic limitation of, and the fragmentary nature of, language signals.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.9-16
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• 2019

Recently, precast PSC girder bridges have been widely applied for short and middle span bridges. The construction of the spliced girder bridges has been increasing to overcome the length limit of girder and transportation restrictions. In case of the spliced girder, the integrity of the segmental joints is very important to secure the structural soundness of bridge because the discontinuity on the segmental joints between adjacent segments could be vulnerable point. The study of segmental joint behavior with different influence factors of joint type, shear key installation, confining force is very important. In this research, finite element analysis and scaled model test with different shear key shapes and confining forces were carried out and the comparative study was performed to evaluate the segmental joint behavior of precast spliced PSC girder bridge. It was confirmed that the installation of shear key with height and depth ratio of 1/2~1/3 and applying of confining force of 1/2 of the concrete strength at the joint was effective in improving the integrity of segmental joint. In addition, the field loading test for existed precast spliced PSC girder bridge was performed and the measurement of the difference of deflection between adjacent segments at segmental joint was proposed as the assessment solution of the integrity of segmental joint.

• Korean Journal of Clinical Laboratory Science
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• v.55 no.1
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• pp.37-44
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• 2023

Enterotoxigenic Bacteroides fragilis (ETBF) has been reported to promote colitis and colon cancer through the secretion of B. fragilis toxin (BFT), a zinc-dependent metalloprotease. In colonic epithelial cells, BFT induces the cleavage of E-cadherin into the 80 kDa ectodomain and the 33 kDa membrane-bound intracellular domain. The resulting membrane-tethered fragment is then cleaved by γ-secretase forming the 28 kDa E-cadherin intracellular fragment. The 28 kDa cytoplasmic fragment is then degraded by an unknown mechanism. In this study, we found that the 28 kDa E-cadherin intracellular fragment was degraded by the proteasome complex. In addition, we found that this sequential E-cadherin cleavage mechanism is found not only in colonic epithelial cells but also in the human breast cancer cell line, BT-474. Finally, we report that staurosporine also induces E-cadherin cleavage in the human breast cancer cell line, MCF7, through γ-secretase. However, further degradation of the 28 kDa E-cadherin intracellular domain is not dependent on the proteasome complex. These results suggest that the BFT-induced E-cadherin cleavage mechanism is conserved in both colonic and breast cancer cells. This observation indicates that ETBF may also play a role in the carcinogenesis of tissues other than the colon.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.283-286
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• 2009

척추경 나사못을 이용한 요추 유합술은 가장 보편적으로 사용되어지는 수술적 치료 방법이다. 과거 여러 연구들에서 이러한 척추 유합술의 임상적 우수성은 이미 입증 되었으며, 척추경 나사못은 시술 부위의 운동을 완전히 제한함으로써 높은 유합율을 얻을 수 있으나, 상대적으로 인접 분절의 조기 퇴행성 변화의 요인 중 하나로 보고되고 있다. 따라서 본 연구에서는 유한요소해석 방법을 이용하여 척추경 나사못 시술에 따른 척추체의 운동범위 및 인접 분절 추간판의 스트레스 증가량을 계산하였고, 척추경 나사못 모델과 유합 후 나사못 제거에 따른 모델 또 시술하기 전 정상모델과 비교하여 생체 역학적 측면에서 분석하여 척추경 나사못을 이용한 요추 유합술 후, 척추경 나사못의 제거의 임상적 효과와 그 이론적 근거를 제시하고자 한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.14 no.6
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• pp.663-674
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• 1989

In order to design the automatic processing system of image document, the pattern segmentation of image document and classification methods are presented. The contour extraction using first order differential operator of Gauassian distribution fucntions, the image segmentation using the chain code, and the pattern classication using the second order moments and two=dimensional Rf distance(in transform domain) are implemented. The resuts applied in specially documantated image shows to classify the characters, fingerprints, seals etc well. And the utility of the used algorithms is verified.