• Proceedings of the KSR Conference
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• 2003.10c
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• pp.473-478
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• 2003

The hydraulic buffer stop placed on the end of the railway brakes the train could not reduce the velocity sufficiently because of the braking system troubles or driver's mistakes. The hydraulic buffer stop is composed of 2 operating parts; hydraulic buffers and rail clamps. Hydraulic buffers brake trains non-destructively in low speed, otherwise rail clamps begin to work in higher speed. In this paper, The braking process of the hydraulic buffer stop is investigated by numerical methods. The hydraulic buffer is numerically analyzed and designed to absorb the kinematic energy of the train below 3.2km/h speed. The hydraulic buffer stop crushed by the train with 5km/h speed is analyzed by FEM package-PAM CRASH in order to obtain the stress profile in rail clamps and buffer stop frame.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.2
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• pp.98-105
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• 2013

The purpose of this study was to investigate the mesiodistal widths at the cervical level of primary second molars in Korean children, and to compare them with commercial rubber dam clamps commonly used in pediatric dentistry. Dental casts of 115 primary and mixed dentition children were studied. Cervical mesiodistal width (C-MD) was measured at the clinical cervical level of each primary second molar from buccal and lingual sides using a digital caliper (Absolute, Mitutoyo, Kawasaki, Japan). The data were compared with mesiodistal widths of rubber dam clamps #203/204, #10/11, and #205 (Dentech, Japan). C-MDs of primary mandibular second molars were larger than those of primary maxillary second molars, and C-MDs at buccal sides were larger than those of lingual sides. All C-MDs showed statistically significant discrepancies to corresponding widths on clamps (p < 0.05). However the amount of discrepancy was mild in maxillary teeth, while up to 1 mm of discrepancy was shown in mandibular teeth. In conclusion, C-MDs measured in this study imply a relatively fair fit of #10/#11 or #203/#204 clamps on primary maxillary second molars, while suggesting our need for a better clamp with proper size for primary mandibular second molars.

• Steel and Composite Structures
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• v.27 no.4
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• pp.453-464
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• 2018

The objective of this study is to devise an alternative strengthening method to the ones available in the literature. So, external steel members were used to enhance both flexural and shear capacities of reinforced concrete (RC) beams having insufficient shear capacity. Two types of RC beams, one without stirrups and one with lacking stirrups, were prepared in the study. These beams were strengthened with external steel clamps devised by the authors and with external longitudinal reinforcements. Although the use of clamps alone didn't have a significant effect on the load carrying capacity of the tested beams, the ductility increased approximately tenfold and the failure behavior changed from brittle to ductile. Although the use of clamps and longitudinal reinforcements together did not significantly increase the ductility of the beams, it approximately doubled their load capacities. The results of the experimental study were compared to the ones obtained from nonlinear finite element analysis (NLFEA) and it was observed that they were compatible. Finally, it can be concluded that the devised method could be applied to structural members as an alternative to methods in application due to lightness, low-cost, easy applicable and reliable.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.519-522
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• 1999

This study was performed to determine the effects of anastomosis on the internal diameter and wall thickness of jugular vein. Tro shepherd dogs were used for this experiment. In dog 1, xylazine(2 mg/kg) and ketamine(5.5 mg/kg) were injected intramuscularly for induction followed by enflurane(3%) anesthesia. In dog 2, acepromazine(0.03 mg/kg) and ketamine(5 mg/kg) were injected intravenously for induction followed by enflurane(3%) anesthesia. The dogs were heparinized(1 mg/kg) for the prevention of thrombosis. After jugular vein was exposed by incision of left cervical area, two Johns Hopkins bulldog clamps were clamped. Jugular vein was cut between two clamps, and it was reanastomosed using 5-0 silk. Ultrasonography was done along the jugular vein on both sides of each dogs 21 days after anastomosis surgery. The internal diameter and circumference of the vein in the anastomosis area were markedly reduced with thickening of the vein wall, but no thrombi were observed.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.3
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• pp.339-344
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• 2014

This paper presents a novel bipolar junction transistor (BJT) based electrostatic discharge (ESD) protection device. This protection device was designed for 20V power clamps and fabricated by a process with Bipolar-CMOS-DMOS (BCD) $0.18{\mu}m$. The current-voltage characteristics of this protection device was verified by the transmission line pulse (TLP) system and the DC BV characteristic was verified by using a semiconductor parameter analyzer. From the experimental results, the proposed device has a trigger voltage of 29.1V, holding voltage of 22.4V and low on-resistance of approximately $1.6{\Omega}$. In addition, the test of ESD robustness showed that the ESD successfully passed through human body model (HBM) 8kV. In this paper, the operational mechanism of this protection device was investigated by structural analysis of the proposed device. In addition, the proposed device were obtained as stack structures and verified.

• Structural Engineering and Mechanics
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• v.50 no.1
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• pp.121-135
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• 2014

Stone masonry structures are widely used around the world, but they deteriorate easily, due to low shear strength capacity. Many techniques have been developed to increase the shear strength of stone masonry constructions. The aim of this experimental study was to investigate the performance of stone masonry walls strengthened by metal connectors as an alternative shear reinforcement technique. For this purpose, three new metal connector (clamp) types were developed. The shear strength of the walls was improved by applying these clamps to stone masonry walls. Ten stone masonry walls were structurally tested in diagonal compression. Various parameters regarding the in-plane behavior of strengthening stone masonry walls, including shear strength, failure modes, maximum drift, ductility, and shear modulus, were investigated. Experimentally obtained shear strengths were confirmed by empirical equations. The results of the study suggest that the new clamps developed for the study effectively increased the levels of shear strength and ductility of masonry constructions.

• Journal of Mushroom
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• v.9 no.1
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• pp.3-16
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• 2011

In the bipolar basidiomycete Pholiota nameko, a pair of homeodomain protein genes located at the A mating-type locus regulates mating compatibility. In the present study, we used a DNA-mediated transformation system in P. nameko to investigate the homeodomain proteins that control the clamp formation. When a single homeodomain protein gene (A3-hox1 or A3-hox2) from the A3 monokaryon strain was introduced into the A4 monokaryon strain, the transformants produced many pseudo-clamps but very few clamps. When two homeodomain protein genes (A3-hox1 and A3-hox2) were transformed either separately or together into the A4 monokaryon, the ratio of clamps to the clamp-like cells in the transformants was significantly increased to approximately 50%. We, therefore, concluded that the gene dosage of homeodomain protein genes is important for clamp formation. When the sip promoter was connected to the coding region of A3-hox1 and A3-hox2 and the fused fragments were introduced into NGW19-6 (A4), the transformants achieved more than 85% clamp formation and exhibited two nuclei per cell, similar to the dikaryon (NGW12-163 ${\times}$ NGW19-6). The results of real-time RT-PCR confirmed that sip promoter activity is greater than that of the native promoter of homeodomain protein genes in P. nameko. So, we concluded that nearly 100% clamp formation requires high expression levels of homeodomain protein genes and that altered expression of the A mating-type genes alone is sufficient to drive true clamp formation.

• Journal of fish pathology
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• v.19 no.2
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• pp.99-108
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• 2006

Diseased tiger puffer (Takijugu rubripes) showed anorexia and severe anemia in the gills. In wet mount preparations Heterobothrium sp. with 4 sets of clamps on the opisthohaptor attached to the gill filaments of the diseased fish. From the drum-shaped filter for filtration of the culturing water and the sediment of aquarium held the diseased fish in the laboratory, their eggs forming long strings through connection of the bipolar filaments could be easily collected. The parasites with 4 pairs of clamps on the opisthohaptor were 2.38mm in length and 0.71 mm in width, but had no isthmus which was separated the opisthohapor from the body proper. The parasites could be easily distinguished from Heterobothrium tetrodonis and H. okamotoi in the absence of distinct isthmus, and resembled H. yamagutii described from the gills of Takifugu xanthopterus in Japan. Their eggs were yellowish spindle in shape and 180-200 x 5-6 Iffil in size, which were pointed at both ends. The eggs were linked to adjacent egg shells like a string of beads by the filaments. Onchomiracidia, ciliated larvae spawned from the eggs were 133 Iffil (120-146 Iffil) x 751ffil (68-80 Iffil) in size. The length of the ciliates was 12 Iffil in the anterior part of the larvae and 14 Iffil in the posterior part. Round or leaf-shaped young parasites attached on the secondary gill lamellae. There was a tendency that most of round smaller parasites without an opisthohaptor were found in the middle part of the gill lamellae while leaf-shaped larger ones with a opisthohaptor attached on the distal part of the gill filaments. Each clamp of mature parasites grasped one secondary gill filament which resulted in bending of the filaments and hyperplasia of the epithelium and mucous cells. In the branchial cavity around the pseudobranch, mature parasites grasped the adjacent ones by means of the clamps, and the epithelia of the branchial cavity around the parasites showed severe irregular hyperplasia and erosion with strongly PAS-positive mucous cells.

• Composites Research
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• v.34 no.1
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• pp.8-15
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• 2021

In the shipbuilding and marine industry, as a technology for reducing the weight of parts to reduce energy and improve operational efficiency of ships is required, a method of applying fibers-reinforced composites which is high-strength lightweight materials, as part materials can be considered. In this study, the possibility of applying fibers-reinforced composites to the pipe support clamps was evaluated to reduce the weight of LNGC. The fibers-reinforced composites were manufactured using carbon fibers and glass fibers as reinforcing fibers. Through the computer simulation program, the properties of the reinforcing materials and the matrix materials of the composites were inversely calculated, and the performance prediction was performed according to the change in the properties of each fiber lamination pattern. In addition, the structural analysis of the clamps according to the thickness of the composites was performed through the finite element analysis program. As a result of the study, it was confirmed that attention is needed in selecting the thickness when applying the fibers-reinforced composites of the clamp for weight reduction. It is considered that it will be easy to change the shape of the structure and change the structure for weight reduction in future supplementary design.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.3
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• pp.17-24
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• 2008

Rail clamps are mechanical components installed to fix the container crane to its lower members against wind blast or slip. According to rail clamps should be designed to survive harsh wind loading conditions. In this study, a jaw structure, which is a part of a wedge-typed rail clamp, is optimized with respect to its strength under a severe wind loading condition. According to the classification of structural optimization, the structural optimization of a jaw is included in the category of shape optimization. Conventional structural optimization methods have difficulties in defining complex shape design variables and preventing mesh distortions. To overcome the difficulties, the metamodel using Kriging interpolation method is introduced to replace the true response by an approximate one. This research presents the shape optimization of a jaw using iterative Kriging interpolation models and a simulated annealing algorithm. The new Kriging models are iteratively constructed by refining the former Kriging models. This process is continued until the convergence criteria are satisfied. The optimum results obtained by the suggested method are compared with those obtained by the DOE (design of experiments) and VT (variation technology) methods built in ANSYS WORKBENCH.