• Journal of the Korea institute for structural maintenance and inspection
• /
• v.9 no.2
• /
• pp.199-206
• /
• 2005

In many other countries framed structures with inadequate lateral strength and stiffness have been strengthened by providing reinforced concrete infilled wall. There is a general agreement among researchers those infilled walls have 3-5times greater lateral strength compared with bare frame. The main objective of this research is to investigate the behavior and strength of reinforced concrete frames infilled with concrete block and cast-in-place reinforced concrete panels used for strengthening the structure against seismic action. For this purpose three 1/3 scale, one-bay, one-story reinforced concrete infilled frames were tested under reversed cyclic loading simulating the seismic effect. The results indicate that infilled walls increase both strength and stiffness significantly under lateral loads. Especially Strength capacity and initial stiffness of CIP infilled wall increased 3.8 times and 6.6 times higher than lightly reinforced concrete frame.

• Journal of the Korea Concrete Institute
• /
• v.24 no.6
• /
• pp.737-744
• /
• 2012

Hysteretic steel damper has been applied mainly to steel buildings. However, the usage in RC buildings is rapidly increasing recently. In order to apply the steel hysteretic damper in RC buildings, supporting elements of the damper should have sufficient strength and stiffness suitable for transferring damper forces to beams and walls. But due to the inevitable damage in reinforced concrete elements due to cracking, identification of the load transfer mechanism from damper to supporting element and hysteretic characteristics of the supporting element are extremely important in evaluating the damper behavior. Experiments were carried out on connection details between RC walls and supporting elements of the steel plate typed damper such as EaSy damper. The test results showed that fracture patterns of all specimens were almost identical except in the crack number and pattern associated with shear loading condition. Among the specimens, HD-3 shoed a well distributed cracks patterns along with good performance with respect to energy dissipation capacity, stiffness deterioration, and strength degradation.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.10
• /
• pp.1452-1458
• /
• 2004

An experiment was conducted to examine the effects of sex and market weight on performance, carcass characteristics and pork quality. A total of 224 crossbred pigs (initially 26.64 kg BW) were allotted in a $2{\times}4$ factorial arrangement in a randomized complete block (RCB) design. The variables were sex (gilts and barrows) and different market weights (100, 110, 120 and 130 kg). Average daily gain (ADG) and average daily feed intake (ADFI) were significantly higher (p<0.01) in barrows than gilts, ADFI and feed conversion ratio (FCR) increased as body weight increased (p<0.05). Gender differences were observed in carcass characteristics. Backfat thickness and drip loss were greater in barrows (p<0.01), while loin eye area (p<0.01), flavor score (p<0.05) and lean content (p<0.001) were higher in gilts. Carcass grade and water holding capacity were the highest in 110 kg market weight pigs. The 100 kg arket weight pigs showed lower juiciness, tenderness, shear forces and total palatability than the other market weights (p<0.01). Hunter values (L*, a* and b*) were increased as market weight increased (p<0.05). Hunter a* value was greater in gilts (p<0.01) but L* value and b* value were not affected by sex of pigs. Net profit [(carcass weight${\times}$price by carcass grade)-(total feed cost+cost of purchased pig)] was higher in gilts than barrows (p<0.01), and was higher (p<0.05) in the pigs marketed at 110 and 120 kg market weight compared with 100 kg market weight. These results demonstrated that gilts showed higher carcass characteristics, pork quality, feed cost per kg body weight gain and net profit compared with barrows. Moreover, 110 or 120 kg body weight would be the recommended market weight based on pork quality and net profit for swine producers.

• Journal of Animal Science and Technology
• /
• v.62 no.5
• /
• pp.753-760
• /
• 2020

The objective of this study was to investigate the influence of increasing carcass weight (CW) on meat quality traits including meat color, water-holding capacity (WHC), tenderness, backfat thickness and intramuscular fat (IMF) content of pork loin. A total of 96 pork carcasses (48 LYD [Landrace × Yorkshire × Duroc] barrows and gilts) were selected at a commercial slaughterhouse. Each gender had commercial CW (≤ 90 kg), heavy CW (91-100 kg) and very heavy CW (> 100 kg) (16 carcasses from each CW group). Loin cuts (Longissimus lumborum) were excised to investigate meat color (CIE L*a*b*), drip loss, cooking loss, released water, Warner-Bratzler shear force (WBSF), and IMF content. Backfat thickness and IMF content of pork loin samples were significantly (p < 0.05) increased with increasing CW, although there was no significant difference in ultimate pH (pHu). CIE a* increased significantly (p < 0.05) with increasing CW, while there were no significant differences in CIE L* or CIE b* among CW groups. Although all WHC measures showed no significant differences among CW groups, WBSF increased significantly (p < 0.01) with increasing CW. Sensory flavor score was significantly increased while panel score for tenderness was decreased significantly (p < 0.001) with increasing CW. Consequently, CW had a positive correlation with flavor but negative correlation with tenderness. These results indicate that the increased IMF content improves flavor, juiciness and palatability, although tenderness deteriorates with increasing CW.

• Computational Structural Engineering
• /
• v.5 no.1
• /
• pp.109-118
• /
• 1992

Lateral bracing has long been used in design practice to enhance the carrying capacity of the lateral buckling of the beam. Many factors, critically important to lateral bracing performance, do not appear in design formulas. Some of these factors are discussed in this study for the application to short I - beams under repeated loadings through parametric studies with an analytical model : the brace location along the length of the beam, the height of the bracing above the shear center of the beam, and the strength and stiffness of the brace. The parametric studies are carried out using a propped cantilever arrangement, and also using a geometrically (fully) nonlinear beam model for the brace as well as the beam to capture the system buckling. An idealized bracing system is configured to restrain lateral motion, but not rotation. A multiaxial cyclic plasticity model is also implemented to better represent cyclic metal plasticity in conjunction with a consistent return mapping algorithm.

• KIEAE Journal
• /
• v.15 no.1
• /
• pp.139-146
• /
• 2015

This is an experimental study on the engineering characteristics of perforated reinforced concrete beams with shells. In the material matter of this study, the water cement ratio put 60%, the ratio of substitution of oyster shells to fine aggregate 30%. And in the structural matter, the form of opening put circle and square, the size of opening as the radius and the length of it changed from one to three times of the beam depth with a change presence and absence of reinforced steel around opening. All thirteen reinforced concrete beam tests composed one standard beam and twelve six beams with the circle and square opening were tested in shear strength under two points loading and compared and analyzed the characteristics of test beams under the same conditions one another. The results of the study showed as followed. 1) The initial crack load value of the opening test beams is similar the standard beam but the maximum load value decreased with increase in proportion of the opening size, in the square opening than the circle opening and in the absence than the presence of reinforced steel. 2) As the difference between the circle opening and the square opening beams is represented 2.17~9.8% in the maximum load value and the load capacity of the square opening suddenly decrease than it of the circle opening, it is judged because of the shortage of concrete section, the concentration of the stress in the corner of the square opening and material influence of shell substitution. 3) The failure figure such as the pattern of the crack and so on is represented brittle failure as the opening size is the bigger and the ratio of substitution is higher because of the lack material properties.

• Earthquakes and Structures
• /
• v.8 no.2
• /
• pp.305-377
• /
• 2015

The problem of earthquake induced torsion in buildings is quite old and although it has received a lot of attention in the past several decades, it is still open. This is evident not only from the variability of the pertinent provisions in various modern codes but also from conflicting results debated in the literature. Most of the conducted research on this problem has been based on very simplified, highly idealized models of eccentric one-story systems, with single or double eccentricity and with load bearing elements of the shear beam type, sized only for earthquake action. Initially, elastic models were used but were gradually replaced by inelastic models, since building response under design level earthquakes is expected to be inelastic. Code provisions till today have been based mostly on results from one-story inelastic models or on results from elastic multistory idealizations. In the past decade, however, more accurate multi story inelastic building response has been studied using the well-known and far more accurate plastic hinge model for flexural members. On the basis of such research some interesting conclusions have been drawn, revising older views about the inelastic response of buildings based on one-story simplified model results. The present paper traces these developments and presents new findings that can explain long lasting controversies in this area and at the same time may raise questions about the adequacy of code provisions based on results from questionable models. To organize this review better it was necessary to group the various publications into a number of subtopics and within each subtopic to separate them into smaller groups according to the basic assumptions and/or limitations used. Capacity assessment of irregular buildings and new technologies to control torsional motion have also been included.

• Journal of the Korean Applied Science and Technology
• /
• v.33 no.3
• /
• pp.575-586
• /
• 2016

An experiment was carried out to determine the effect of cooling water treatment with ionized calcium on calcium content, extending the shelf-life and quality of fresh chicken meat in poultry slaughtering process. The subjects were divided into four groups: control (0% without ionized calcium) and treatment groups (0.5, 0.7, 0.9% ionized calcium). The results indicated that the cooling water treatment with ionized calcium exhibited the bacterial counts of $10^5CFU/cm^2$ in surface of chicken meat, and maintained the quality of fresh chicken meat with extending the shelf-life above seven days when compared with that of control group. The results found that the cooling water treatment with ionized calcium could produce the calcium enrichment of chicken meat as nine times higher in calcium content of chicken meat when compared with that of control group. pH, water holding capacity, TBARS (MDA mg/kg) in chicken meat via the cooling water treatment with ionized calcium showed 6.4, above 50, below 0.10, respectively, with preventing the oxidation of unsaturated fatty acids. Lightness ($L^*$) as a chicken meat color, shear force indicated above 60, below $1.70kg/0.5inch^2$, respectively.

• Food Science of Animal Resources
• /
• v.35 no.4
• /
• pp.449-458
• /
• 2015

The effects of quality grade and storage time on physicochemical, sensory properties and microbial population of Hanwoo striploin beef were investigated. After a total of 30 Hanwoo beef were slaughtered, the cold carcasses were graded by official meat grader at 24 h postmortem. The carcasses were categorized into five groups (quality grade 1++, 1+, 1, 2, and 3) and were vacuum-packaged and stored. The samples were kept for 1, 4, 6, 8, 11, 13, 15, 18, 20, 22 and 25 d for analyses. As the quality grade was increased, moisture, protein and ash contents decreased (p<0.05). Higher quality grade corresponded with higher fat contents. The shear force values decreased with increasing quality grade and showed decreases sharply during the first 4 d (p<0.05). pH, water holding capacity, cooking loss, and volatile basic nitrogen for grade 1++ groups were lower than for grade 3 (p<0.05). CIE L* and b* values increased as increased quality grade (p<0.05). Meat color decreased until 13 d and fluctuated after 15 d of storage (p<0.05). Regarding the sensory scores, higher quality grade corresponded with higher juiciness, tenderness, flavor, fatty and palatability scores (p<0.05). Generally, increased storage time for 15 d improved sensory scores attributes. Results indicate that a high quality grade could positively influence physicochemical and sensory properties.

• Journal of Animal Science and Technology
• /
• v.57 no.7
• /
• pp.24.1-24.5
• /
• 2015

The objective of this study was to investigate the physicochemical and microbial quality of loin (m. longissimus dorsi) and top round (m. Semimembranosus) in Holstein veal produced from two slaughter age groups (5 and 8 months of age). A total of 20 Holstein calves were randomly selected from a local cattle farm. The slaughtered cold carcasses were vacuum-packaged. The samples were analyzed for proximate composition and physicochemical analyses and stored for 1, 7, 10, 20 and 30 days for microbiological analyses. Fat and protein contents of loin for the 8 month group were higher than those for the 5 month groups (p < 0.05). For both loin and top round muscles, the pH, cooking loss and the shear force values for the 5 month group was higher than those for the 8 month group (p < 0.05). On the other hands, the water-holding capacity (WHC) for the 8 month group was higher than those for the 5 month group (p < 0.05). In terms of meat color, CIE $L^*$ (lightness) for both muscle were higher in the 5 month group than in the 8 month groups. On the other hands, $a^*$ (redness) were higher in the 8 month group than in the 5 month groups (p < 0.05). Total aerobic counts in all samples remained up to 30 days at values less than 7 log CFU/g. However, there was no significant difference for both muscles between the two age groups. The results indicate that Holstein muscles from the 8 month group had desirable quality properties than those from the 5 month group.