• 한국지반신소재학회논문집
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• 제10권3호
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• pp.43-51
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• 2011

본 연구에서는 수동저항부를 형성시킨 띠형 섬유보강재의 인발저항 특성을 평가하기 위해 일련의 실내인발시험을 수행하였다. 이 띠형 섬유보강재는 중간에 길이방향으로 접힘홈이 형성되어 있어 보강재를 반폭으로 접어 콘크리트 블록에 직접 체결할 수 있고 후단부에는 보강재를 '${\cap}$' 형태로 세워서 수동저항부를 형성시킬 수 있다. 이 띠형 섬유보강재는 후단부에 수동저항부가 형성되어 있기 때문에, 흙과 보강재 사이의 표면마찰저항과 수동저항부에서의 지지저항력이 함께 발현되는 인발저항 특성을 가진다. 따라서, 인발저항 평가시 마찰저항과 지지저항을 각각 산정하여 설계에 반영해야 한다. 일련의 인발시험 결과 수동저항부를 형성시키면 인발저항강도가 10~65% 정도 증가하고 수직응력이 클수록 증가량이 점차 커지는 경향을 보이는 것으로 나타났으며, 이를 근거로 수동저항부 형성에 의해 발현되는 지지저항력 산정 방법을 제안하였다.

• Journal of Microbiology and Biotechnology
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• 제26권11호
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• pp.1855-1862
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• 2016

Cronobacter sakazakii (C. sakazakii) is a foodborne pathogen, posing a high risk of disease to infants and immunocompromised individuals. In order to develop a quick, easy, and sensitive assay for detecting C. sakazakii, a rabbit anti-C. sakazakii immunoglobulin G (IgG) was developed using sonicated cell protein from C. sakazakii. The developed anti-C. sakazakii (IgG) was of good quality and purity, as well as species-specific. The developed rabbit anti-C. sakazakii IgG was attached to the surface of a sulforhodamine B-encapsulated liposome to form an immunoliposome. A test strip was then prepared by coating goat anti-rabbit IgG onto the control line and rabbit anti-C. sakazakii IgG onto the test line, respectively, of a plastic-backed nitrocellulose membrane. A purple color signal both on the test line and the control line indicated the presence of C. sakazakii in the sample, whereas purple color only on the control line indicated the absence of C. sakazakii in the sample. This immunochromatographic strip assay could produce results in 15 min with a limit of detection of $10^7CFU/ml$ in C. sakazakii culture. The immunochromatographic strip assay also showed very good specificity without cross-reactivity with other tested Cronobacter species. Based on these results, the developed immunochromatographic strip assay is efficient for the detection of C. sakazakii and has high potential for on-site detection.

• 한국토양비료학회지
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• 제36권5호
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• pp.272-279
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• 2003

본 연구는 지금까지 제시된 여러 가지 간이 영양 진단 방법들 중 test strip과 chlorophyll meter를 이용하여 오이의 영양상태를 신속하게 파악하기 위한 방안을 모색하고자 시행하였다. 본 실험에서는 양액에 공급하는 N, P, K 수준을 달리하여 오이를 재배하면서 생육시기별로 specific color difference sensor value (SCDSV), 엽병의 즙액 내 $NO_3$, $PO_4$, K의 함량을 측정하였다. 실험 결과 양액 중 N, P, K의 농도변화에 따른 엽병 중 $NO_3$, $PO_4$, K 함량 변화가 엽 내 total-N, P, K 함량의 변화보다 더 민감하였다. Test strip을 이용하여 구한 오이 엽병 즙액 내 $NO_3$, $PO_4$, K 함량은 엽 내 total-N, P, K의 농도와 고도의 일차상관관계를 나타내었다. 따라서 지금까지 여러 연구를 통해 확립된 오이의 엽 내 total-N, P, K의 적정함량을 회귀식에 대입하여 즙액 $NO_3$, $PO_4$, K의 적정함량을 계산하였다. 오이 즙액의 적정 $NO_3$, $PO_4$, K 범위는 각각 5.4-9.1, 0.2-0.5, $3.1-4.8g\;L^{-1}$였다. Chlorophyll meter를 이용하여 측정한 SCDSV는 엽 내 total-N와 높은 상관관계를 나타내었으며 기존에 연구된 오이의 엽 내 total-N 함량을 회귀식에 대입하여 계산한 결과 적정 SCDSV는 39.5-49.0이었다. 본 연구 결과 test strip과 chlorophyll meter는 오이의 신속한 영양 진단에 이용할 수 있을 것으로 판단된다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1998년도 춘계학술대회논문집
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• pp.144-147
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• 1998

VCR is a back-up roll with a special contour which leads to the length of the contact line between back-up roll and work becones self adjustable in accordance with the width of the strip. The simulation of a finite element model and the on-line test at production mill demonstrate that the VCR roll may keep the crown of the roll gap relatively stable, and at same time, permit the rolling pressure to be adjusted over a wider range, and increase the effect of work roll bending on the roll gap. The VCR rolls have been successfully used at the first stands of two largest cold rolling mills in China, and on-line test has been done at a wide hot strip finishing train. The use of VCR roll has created favorable conditions for subsequent rolling passes and the achievement of better flatness quality.

• Journal of Periodontal and Implant Science
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• 제27권3호
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• pp.549-559
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• 1997

The purpose of this study was to evaluate clinical changes in graft size after treatment with strip gingival autograft in human. 57 premolar teeth in 27 patients having the following mucogingival problems were selected. The width of extension, attached gingiva including free marginal gingiva, width of transplant and clinical sulcus depth were measured at the initial examination, 2, 12 and 24 weeks following the strip gingival autograft and free gingival autograft. The change of width of extension, attached gingiva including free marginal gingiva, width of transplant and clinical sulcus depth according to healing process in both graft procedures was statistically analyzed by repeated measure ANOVA test and independent t-test using SPSS program. The results were as follows : 1. The change of keratinized gingiva in both graft procedures was increased significantly at 24 weeks post-op. 2. The clinical sulcus depth exhibited no marked changes throughout the entire investigation in both graft procedures. 3. No dimensional variation was seen in graft size in both graft procedures. 4. Shrinkage did not differ significantly in both graft procedures. From the day of grafting to 24 weeks after surgery the percentages of shrinkage were : strip gingival autograft 28% and free gingival autograft 29%.

• International Journal of Aeronautical and Space Sciences
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• 제17권3호
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• pp.285-295
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• 2016

A contact strip shape of a high speed train pantograph system was optimized with CFD to increase the aerodynamic performance and stability of contact force, and the results were validated by a wind tunnel test. For design of the optimal contact strip shape, a Kriging model and genetic algorithm were used to ensure the global search of the optimal point and reduce the computational cost. To enhance the performance and robustness of the contact strip for high speed pantograph, the drag coefficient and the fluctuation of the lift coefficient along the angle of attack were selected as design objectives. Aerodynamic forces were measured by a load cell and HWA (Hot Wire Anemometer) was used to measure the Strouhal number of wake flow. PIV (Particle Image Velocimetry) was adopted to visualize the flow fields. The optimized contact strip shape was shown a lower drag with smaller fluctuation of vertical lift force than the general shaped contact strip. And the acoustic noise source strength of the optimized contact strip was also reduced. Finally, the reduction amount of drag and noise was assessed when the optimized contact strip was applied to three dimensional pantograph system.

• Steel and Composite Structures
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• 제27권1호
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• pp.123-133
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• 2018

Steel-concrete-steel (SCS) sandwich composite structure with corrugated-strip connectors (CSC) has the potential to be used in buildings and offshore structures. In this structure, CSCs are used to bond steel face plates and concrete. To overcome executive problems, in the proposed system by the authors, shear connectors are one end welded as double skin composites. Hence, this system double skin with corrugated-strip connectors (DSCS) is named. In this paper, finite element model (FEM) of push-out test was presented for the basic component of DSCS. ABAQUS/Explicit solver in ABAQUS was used due to the geometrical complexity of the model, especially in the interaction of the shear connectors with concrete. In order that the explicit analysis has a quasi-static behavior with a proper approximation, the kinetic energy (ALLKE) did not exceed 5% to 10% of the internal energy (ALLIE) using mass-scaling. The FE analysis (FEA) was validated against those from the push-out tests in the previous work of the authors published in this journal. By comparing load-slip curves and failure modes, FEMs with suitable analysis speed were consistent with test results.

• Design & Manufacturing
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• 제6권1호
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• pp.34-38
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• 2012

Test work is the press die branch at The Korea-China-Japan Grand Prize Contest. This study focuses on strip layout design for test work. A comparison is drawn between product shape and blank deployment line. During the forming analysis of the whole product, shape part of the total forming process is analyzed. As for forming part and flange deployment, forming analysis is carried out in part during the mid process. Material utilization is 42.6 percent and strip layout design is completed in 14 processes that are comprised of hourglass, slotting, embossing, drawing and trimming.

• 소성∙가공
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• 제21권3호
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• pp.172-178
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• 2012

We performed a shot peening test and used a 2-D finite element model which predicts the compressive residual stress distribution below the material's surface. In this study, the concept of 'impact cycle' is introduced to account for the irregularity in the shot's impact position during testing. The impact cycle was imbedded in the finite element model. In the shot peening test, shot bombarded a type-A Almen strip surface with different impact velocities. To verify the proposed finite element model, we compared the deformed cross sectional shape of the Almen strips with the shapes computed by the proposed finite element model. Good agreement was noted between measurements and the finite element model predictions. With the verified finite element model, a series of finite element simulations was conducted to compute the residual stress distribution below the material's surface and the characteristics of these distributions are discussed.

• 소성∙가공
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• 제15권9호
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• pp.660-666
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• 2006

This study examined the mechanical properties and bending formability evaluation of spring strip materials(SK5 CSPH, STS 301 CSP-EH, C7701-H). The hardness test and tensile test were performed at room temperature($20^{\circ}C$) for mechanical properties. The U-bending test were carried out at various conditions of punch corner radius(Rp), ratio of punch comer radius/thickness(Rp/t) and ratio of clearance/thickness(Rp/t) and ratio of clearance/thickness(C/t) for bending formability evaluation.