• Journal of the Earthquake Engineering Society of Korea
• /
• v.24 no.3
• /
• pp.129-139
• /
• 2020

An approximate analysis method is proposed to predict the dynamic amplification of shear forces in ordinary reinforced concrete shear walls as a preliminary study. First, a seismic design for three groups of ordinary reinforced concrete shear walls higher than 60 m was created on the basis of nonlinear dynamic analysis. Causes for the dynamic amplification effect of shear forces were investigated through a detailed evaluation of the nonlinear dynamic analysis result. A new modal combination rule was proposed on the basis of that observation, in which fundamental mode response and combined higher mode response were summed directly. The fundamental mode response was approximated by nonlinear static analysis result, while higher mode response was computed using response spectrum analysis for equivalent linear structural models with the effective stiffness based on the nonlinear dynamic analysis result. The proposed approximate analysis generally predicted vertical distribution of story shear and shear forces of individual walls from the nonlinear dynamic analysis with comparable accuracy.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.12 no.4
• /
• pp.108-113
• /
• 2013

Industrialization and modernization of the beginning of the IT industry is growing very fast. Since telecommunications industry was developed rapidly, technologies about miniaturization and high-precision of parts have been actively developed to lead information revolution. generally, the entire shear surface of the product applying fine blanking technology must be very precise. Fine blanking is used to save cost by avoiding post-processing of the product. When using press blanking, it spends a lot of money on the production by using many post-processing. Fine blanking typically used in 0.5~18 mm thick steel plate. Because a lot of post-processing cost can be used to process, except for fine blanking. In order to develop components "CHANCE CONTENTS" in the fine blanking process, the purpose of this study is to minimize the edge of the bridge, secured 95% of the material thickness of the shear surface using the 1.6 mm thickness of the material SPCC. Blanking process by introducing after changing thickness through forging process, due to change in vee-rring force and counter force, the experimental amount of depressions and flatness and the shear surface were analyzed.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.9 no.6 s.46
• /
• pp.1-12
• /
• 2005

For a shear-deformable beam-column element subjected io non-conservative forces, equations of motion and a finite element formulation are presented applying extended Hamilton's principle. The influence of non-conservative force's direction parameter, internal and external damping forces, and shear deformation and rotary inertia effects on divergence and flutter loads of Beck's columns are intensively investigated based on element stiffness, damping and mass matrixes derived for the non-conservative system.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.2
• /
• pp.292-298
• /
• 2001

This study was conducted to investigate physicochemical properties of extrudates combining 4 levels of squid (0, 3, 5 and 7%) with 3 levels of defatted soy flour (0, 5, and 10%). Blends were adjusted to moisture content of 27% and then extruded in a single-screw laboratory extruder at 170rpm screw speed and 16$0^{\circ}C$ barrel temperature. The extruded materials were dried at 6$0^{\circ}C$ for 8hr to a moisture content of 3~4% and refrigerated at 4$^{\circ}C$ for 12 hour before examination for textural properties, expansion ratio, bulk density, shear force and Hunter color. Expansion ratio of extrudates decreased as squid content increased whereas bulk density and shear force increased. Expansion ratio of extrudates was not significantly different by defatted soyflour level. Bulk density of products decreased as defatted soyflour content increased but shear force of products increased as defatted soyflour content increased. In scores of sensory hedonic evaluation of snacks, appearance, flavor, texture and overall acceptability values had lowered as squid level increased. Therefore, according to materials contents on extrudates increased, nutritional contents of this products increased and also shear force and bulk density in physical properties increased whereas expansion ratio decreased.

• Computational Structural Engineering
• /
• v.11 no.1
• /
• pp.251-259
• /
• 1998

Concrete shear wall with opening is modeled as a rectangular thin plate. The stability analysis results are presented by the buckling coefficient, k, for two different boundary conditions. The other parameters whose variation have been considered are the ratio of the bending induced force to gravity force, a, the ratio of the horizontal shear force to the gravity force ratio, A and the change of location and the size of perforated part. To obtain the results by finite element method, an example plate has been divided into 27*9 square elements. Four node rectangular c.deg. continuous finite elements having three degrees of freedom per each node is adopted. It is generally concluded that the buckling coefficients decrease as the size of hole increases, and the location of hole moves to free edge of the wall.

• Food Science of Animal Resources
• /
• v.29 no.3
• /
• pp.302-309
• /
• 2009

This study investigated the effects of infrared (IR) radiation combined with air blast thawing on the physical properties of pork. Regardless of air velocity, increasing IR dosage produced an exponential increase in the thawing rate of pork. This rate increased further when air blast velocity was increased. IR treatments showed significantly lower thawing loss than that of 0 Watt treatment, while increasing air velocity significantly increased thawing loss of pork (p<0.05). Increasing both IR power and air velocity tended to decrease the cooking loss of pork. Moreover, increased IR power tended to decrease the water holding capacity and shear force of pork. The shear force changes were not significant (p>0.05). Shear force also increased with increasing air velocity. In addition, the higher the air velocity the higher the shear force of pork. In Commission Internationale de l'Eclairage (CIE) colour determination, control of temperature prevented discolouration from overheating of sample surface. The results suggest that IR dosage combined with air blast has potential in thawed meat quality aspects, and that humidity control could prevent surface drying.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.1
• /
• pp.85-92
• /
• 2015

It is well known that axial tension decreases the shear strength of RC & PSC beams without transverse reinforcement, and axial compression increases the shear resistance. What is perhaps not very well understood is how much the shear resistance capacity is influenced by axial load. RC beams without shear reinforcement subjected to large axial compression and shear may fail in a very brittle manner at the instance of first diagonal cracking. As a result, a conservative approach should be used for such members. According to the ACI Code, the shear strength in web is calculated by effect of axial force and the vertical force in the stirrups calculated by $45^{\circ}$ truss model. This study was performed to examine the effect of axial force in reinforced concrete beams by nonlinear FEM program (ATENA-2D).

• Earthquakes and Structures
• /
• v.9 no.4
• /
• pp.875-891
• /
• 2015

Earthquake can occur anywhere in the world and it is essential to design important members in special structures based on maximum possible forces that can be produced in them under severe earthquake. In addition, since the earthquake is an accidental phenomena and there are no similar earthquakes, therefore the possibility of strong earthquakes should be taken into account in earthquake-resistant design of important structures. Based on this viewpoint, finding the critical acceleration which maximizes internal forces is an essential factor in structural design. This paper proposes critical excitation method to compute the critical acceleration in design of important members in special structures. These critical accelerations are computed so that the columns' internal shear force at the base of the structure at each time step is maximized under constraints on ground motion. Among computed critical accelerations (of each time step), the one which produces maximum internal shear force is selected. A numerical example presents to show the efficiency of critical excitation method in determining the maximum internal shear force and base moment under variety of constraints. The results show that these method can be used to compute the resonant earthquake which have large enough effective duration of earthquake strong motion (between 12.86 sec to 13.38 sec) and produce the internal shear force and base moment for specific column greater than the same value for selected earthquakes in constructing the critical excitation (for different cases about 2.78 to 1.29 times the San Fernando earthquake). Therefore, a group of them can be utilized in developing the response spectrum for design of special structures.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.8
• /
• pp.1332-1338
• /
• 2020

Objective: Meat quality characteristics and sensory attributes were evaluated in three age groups (12, 18, and 24 mo) of one-humped camels of the Saudi Arabian Najdi breed. Methods: Thirty-six male camels (12 for each age group) were used. The Longissimus dorsi muscle from each carcass was divided into three parts and subjected to three ageing periods (1, 5, or 10 d) and evaluated for shear force, myofibril fragmentation index (MFI), expressed juice, cooking loss, and sensory attributes. Results: Age had a significant effect on shear force, MFI, expressed juice quantity, and organoleptic properties. Camels slaughtered at 12 mo exhibited lower shear force and MFI, and higher expressed juice quantity, tenderness, juiciness, and overall acceptability than those slaughtered at 24 mo. Ageing had a significant influence on shear force, MFI, expressed juice quantity, but not on cooking loss. Camel meat aged for 10 d exhibited significantly lower shear force values and expressed juice quantity, and significantly higher MFI compared to that aged for 1 d. However, ageing did not significantly affect sensory attributes, except for tenderness, in camels slaughtered at 18 mo. Conclusion: Both instrumental and sensory evaluations showed that young camel meat has desirable quality characteristics, with superior tenderness and juiciness.

• Food Science of Animal Resources
• /
• v.42 no.2
• /
• pp.332-340
• /
• 2022

The objective of this study was to determine the optimal cooking time by considering the cooking loss, shear force, and off-odor reduction of pork large intestines. Commercial pork large intestines were purchased, quartered perpendicularly, and cooked in boiling water for 40, 120, 180, and 240 min. Cooking loss of the samples increased after 240 min of cooking (10.92, p<0.05) while shear force value was lower at 240 min (4.45) compared to that at other cooking times (p<0.001). The amount of major volatile organic compounds showed a decreasing trend with increasing cooking time. In particular, the amount of methyl pentanoate (17,528.71) and methyl isobutyrate (812.51), compounds with a relatively low odor threshold, decreased significantly after 120 min of cooking and no change was observed thereafter (p<0.05). In addition, the amount of 2-pentanol (3,785.65) and 1-propanol (622.26), possibly produced by lipid oxidation, significantly decreased at the same cooking time (p<0.001). In the principal component analysis, only the 40 min cooking time was significantly different from other cooking time by high amounts of 1-propanol, 2-pentanol, and methyl isobutyrate. In conclusion, in the present study, the optimal cooking time for pork large intestines was 120 min in terms of off-odor reduction, cooking loss, and shear force.