• Animal Bioscience
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• 제37권2호
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• pp.315-322
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• 2024

Objective: The aim of this study was to evaluate the effect of pre-slaughter fasting time on carcass yield, meat quality, blood parameters and glucose metabolism in broilers. Methods: Four hundred and fifty Arbor Acres (AA) broilers at 42 days of age were divided into 5 groups with 6 replicates in each group and 15 chickens as one replicate. Following this period, broilers from each group were distributed among five groups according to preslaughter fasting period as 4, 8, 12, 16, or 20 h. Results: With increasing fasting time, the carcass yield (p<0.01), the breast muscles yield (p<0.01) and the thigh yield (p<0.01) of the broilers were all linearly increased. With increasing fasting time, the L^* values (p<0.01), cooking loss (p = 0.020), moisture content (p<0.01) in the leg muscles linearly downregulated, while the drip loss (p = 0.043), pH_{45 min} (p<0.01) and pH_{24 h} (p<0.01) were linearly upregulated. A trend for a lower (p = 0.071) shear force in the leg muscles was also observed in broilers fasted for longer time. Similar results were also found in breast muscles. The different fasting treatments did not influence the breast muscles glycogen content (p>0.10), while the increase of fasting time resulted in a linear decrease of the blood glucose (p = 0.021) and, more specifically, the glycogen content of the liver and leg muscles (p<0.001). With increasing fasting time, the aspartate transaminase (p<0.01), uric acid (p<0.01), and triglycerides (p<0.01) in serum linearly downregulated, while the alanine aminotransferase was linearly upregulated. Conclusion: The results of this study show a significant influence of fasting time on carcass yield and meat quality in broilers. Moderate fasting (8 to 12 h) before slaughter can reduce the weight loss of broilers. Prolonged fasting (≥16 h) increased body weight loss, decreased slaughtering performance and fluctuating blood indexes of broilers.

• 한국자동차공학회논문집
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• 제4권6호
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• pp.164-174
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• 1996

This paper presents control and response characteristics of a continuously variable ER(electrorheological) damper for small-sized vehicles. The ER damper is devised and its governing equation of motion is derived from the bond graph model. The field-dependent yield shear stresses are distilled from experimental investigation on the Bingham property of the ER fluid. The distilled data are incorporated into the governing system model and, on the basis of this model, an appropriate size of the ER damper is manufactured. After evaluating the field-dependent damping performance of the proposed ER damper, the skyhook control algorithm is formulated to achieve desired level of the damping force. The controller is then experimentally implemented and control characteristics of the ER damper are presented in order to demonstrate superior controllability of the damping force. In addition, response characteristics of the damping force with respect to the electric field with fast on-off frequency are provided to show the feasibility of practical application.

• Asian-Australasian Journal of Animal Sciences
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• 제30권12호
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• pp.1773-1783
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• 2017

Objective: This study evaluated the supplementary effect of higher concentrations of various disaccharides on processing yield, major physicochemical properties, and sensory attributes of Chinese-style pork jerky (CSPJ). Methods: CSPJ samples were prepared by marinating sliced ham (4 mm) with three dissaccharides, including sucrose, lactose, and maltose, at 0%, 15%, 18%, 21%, and 24%. Subsequently, the CSPJ samples were dried and roasted. The moisture content, water activity, crude protein, moisture-to-protein ratio, pH, processing yield, shear force, color, and sensory attributes of the CSPJ samples were evaluated. Results: The quality characteristics of CSPJ samples prepared with sucrose were more acceptable. By contrast, CSPJ samples prepared with lactose showed the lowest scores. However, the processing yield and moisture content were the highest for CSPJ samples prepared with lactose, which may be associated with improved benefits for cost reduction. Furthermore, sucrose and lactose supplementation resulted in contrasting quality characteristics; for example, CSPJ samples with sucrose and maltose supplementation had higher sensory scores for color than samples with lactose supplementation. Additionally, most quality characteristics of CSPJ samples with sucrose supplementation contrasted with those of the samples with lactose supplementation; for example, the samples with sucrose supplementation had higher scores for sensory attributes than those with lactose supplementation. Conclusion: Sucrose supplementation up to 21% to 24% was associated with the highest overall acceptability scores (5.19 to 5.80), enhanced quality characteristics, increased processing yield, and reduced production cost.

• Structural Engineering and Mechanics
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• 제63권3호
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• pp.281-292
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• 2017

Architecture constraints in buildings may typically cause irregularities in the distribution of stiffness and mass and consequently causes non-compliance of centers of mass, stiffness and strength. Such buildings are known as asymmetric buildings the distribution of strength and stiffness is one of whose main challenges. This distribution is more complicated for concrete buildings with RC shear walls in which stiffness and strength are interdependent parameters. The flexibility under the foundation is another subject that can affect this distribution due to the variation of dynamic properties of the structure and its constituting elements. In this paper, it is attempted to achieve an appropriate distribution pattern by expressing the effects of foundation flexibility on the seismic demand of concrete shear walls and also evaluate the effects of this issue on strength and stiffness distribution among lateral force resistant elements. In order to understand the importance of flexibility in strength and stiffness distribution for an asymmetric building in different conditions of under-foundation flexibility, the assigned value to each of the walls is numerically calculated and eventually a procedure for strength and stiffness distribution dependencies on flexibility is provided.

• 대한기계학회논문집A
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• 제24권2호
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• pp.370-377
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• 2000

This paper presents a mixed-mode type ER(electro-rheological) engine mount, and its vibration control performance for a passenger vehicle is presented. The field-dependent yield stress of a transfo rmer oil-based ER fluid is empirically distilled in both shear and flow modes. This is then incorporated with the governing equation of motion of the proposed mixed-mode(shear mode plus flow mode) type engine mount. The damping force is analyzed with respect to the intensity of the electric field and design parameters such as electrode gap. Subsequently, the ER engine mount which is equivalent to the conventional hydraulic engine mount in terms of the damping level is designed and manufactured. Both computer simulation and experimental test are undertaken in order to evaluate vibration isolation performance. In addition, this performance is compared with that of the conventional hydraulic engine mount.

• Structural Engineering and Mechanics
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• 제60권2호
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• pp.237-249
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• 2016

There are constraints on truck weight, axle configurations and size imposed by departments of transportation around the globe due to structural capacity limitations of highway pavements and bridges. In spite of that, freight movers demand some vehicles that surpass the maximum size and legal weight limits to use the transportation network. Oversized trucks serve the purpose of spreading the load on the bridge; thus, reducing the load effect on the superstructure. For such vehicles, often a quick structural analysis of the existing bridges along the traveled route is needed to ensure that the structural capacity is not exceeded. For a wide vehicle having wheel gage larger than the standard 1830 mm, the girder distribution factors in the design specifications cannot be directly used to estimate the live load in the supporting girders. In this study, a simple approach that is based on finite element analysis is developed by modifying the AASHTO LRFD's girder distribution factors for slab-on-steel-girder bridges to overcome this problem. The proposed factors allow for determining the oversized vehicle bending moment and shear force effect in the individual girders as a function of the gage width characteristics. Findings of the study showed that the relationship between the girder distribution factor and gage width is more nonlinear in shear than in flexure. The proposed factors yield reasonable results compared with the finite element analysis with adequate level of conservatism.

• Computers and Concrete
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• 제13권4호
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• pp.547-567
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• 2014

Precast Seismic Structural Systems (PRESSS) provided an iterative procedure for obtaining optimum design of unbonded post-tensioned coupled precast concrete wall systems. Although PRESSS procedure is effective, however, it is lengthy and laborious. The purpose of this research is to employ Artificial Neural Network (ANN) to predict the optimum design parameters for such wall systems while avoiding the demanding iterative process. The developed ANN model is very accurate in predicting the nondimensional optimum design parameters related to post-tensioning reinforcement area, yield force of shear connectors and ratio of moment resisted by shear connectors to the design moment. The Mean Absolute Percent Error (MAPE) for the test data for these design parameters is around %1 and the correlation coefficient is almost equal to 1.0. The developed ANN model is then used to study the effect of different design parameters on wall behavior. It is observed that the design moment and the concrete strength have the most influence on the wall behavior as compared to other parameters. Several design examples were presented to demonstrate the accuracy and effectiveness of the ANN model.

• 한국지진공학회논문집
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• 제18권1호
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• pp.53-61
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• 2014

RC shear wall sections which have irregular shapes such as T, ㄱ, ㄷ sections are typically used in low-rise buildings in Korea. Pushover analysis of building containing such members costs a lot of computation time and needs professional knowledge since it requires complicated modeling and, sometimes, fails to converge. In this study, a method using an equivalent column element for the shear wall is proposed. The equivalent column element consists of an elastic column, an inelastic rotational spring, and rigid beams. The inelastic properties of the rotational spring represent the nonlinear behavior of the shearwall and are obtained from the section analysis results and moment distribution for the member. The use of an axial force to compensate the difference in the axial deformation between the equivalent column element and the actual shear wall is also proposed. The proposed method is applied for the pushover analysis of a 5- story shear wall-frame building and the results are compared with ones using the fiber elements. The comparison shows that the inelastic behavior at the same drift was comparable. However, the performance points estimated using the pushover curves showed some deviations, which seem to be caused by the differences of estimated yield point and damping ratios.

• 한국강구조학회 논문집
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• 제20권4호
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• pp.493-504
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• 2008

본 연구는 속빈 PC 슬래브와 채널을 사용한 매입형 합성보의 휨거동에 관한 것이다. 철골보와 PC슬래브의 경계면에 발생하는 전단력은 채널에 의해서 전달된다. 철골보의 춤에 따라서 총 3개의 실대형 실험체를 제작하여 실험을 수행하였으며 기존에 수행된 전단접합 방식과 비교검토를 수행하였다. 채널 용접형 매입형 합성보의 실험결과, 별도의 전단연결재를 설치하지 않아도 자체가 가지고 있는 기계적․화학적 부착응력으로 인해 완전합성보에 가까운 거동을 나타내었다. 또한, 기존의 합성보의 거동과 같이 탄성구간, 항복구간, 매우 큰 연성, 휨파괴모드(소성힌지), 경계면에서의 매우 낮은 상대슬립 및 연성적인 파괴거동을 나타내었다. 따라서 제안된 전단연결 방식의 경우, 실제 건물에 적용시 규준에서 요구하는 구조적 성능을 만족할 수 있는 것으로 나타났다.

• Earthquakes and Structures
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• 제7권5호
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• pp.817-842
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• 2014

ASCE/SEI 41-13 provides modeling parameters and numerical acceptance criteria for various types of members that are useful for evaluating the seismic performance of reinforced concrete (RC) building structures. To accurately evaluate the global performance of a coupled wall system, it is crucial to first properly define the component behaviors (i.e., force-displacement relationships of shear walls and coupling beams). However, only a few studies have investigated on the modeling of RC coupling beams subjected to earthquake loading to date. The main objective of this study is to assess the reliability of ASCE 41-13 modeling parameters specified for RC coupling beams with various design details, based on a database compiling almost all coupling beam tests available worldwide. Several recently developed coupling beam models are also reviewed. Finally, a rational method is proposed for determining the chord yield rotation of RC coupling beams.