• Journal of Power Electronics
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• v.8 no.3
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• pp.268-274
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• 2008

This paper presents a proposed position controller for a vector controlled induction motor. The position controller design depends on the rotational motion equations and a classical speed controller (CSC) performance. The CSC is designed to have the ability to track variable reference inputs and to provide a predefined system performance. Standard position controller in industry is presented to analyze its performance and its drawbacks. Then the proposed position controller is designed, based on the well defined rotational motion equations. The proposed position controller and the CSC are applied to control the position and speed of the vector controlled induction motor with different ratings. Simulation results at different operating conditions are presented to evaluate the proposed controllers' performance. The results show that the CSC can drive the motor with a predefined speed performance and can track a variable reference speed with an approximately zero steady state error. The results also show that the proposed position controller has the ability to effect high-precision positioning in a limited time and to track a variable reference position with a zero steady state error.

• Earthquakes and Structures
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• v.10 no.4
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• pp.735-755
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• 2016

This article presents a proposed analytical methodology to determine seismic force-resisting system R-values for steel diagrid framed systems. As current model building codes do not explicitly address the seismic design performance factors for this new and emerging structural system, the purpose of this study is to provide a sound and reliable basis for defining such seismic design parameters. An approach and methodology for the reliable determination of seismic performance factors for use in the design of steel diagrid framed structural systems is proposed. The recommended methodology is based on current state-of-the-art and state-of-the practice methods including structural nonlinear dynamic analysis techniques, testing data requirements, building code design procedures and earthquake ground motion characterization. In determining appropriate seismic performance factors (R, ${\Omega}_O$, $C_d$) for new archetypical building structural systems, the methodology defines acceptably low values of probability against collapse under maximum considered earthquake ground shaking.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.3
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• pp.61-71
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• 1998

A performance-based seismic design method for reinforced concrete building structures being developed in Japan is outlined. Technical and scientific background of the performance-based design philosophy as well as recently developed seismic design guidelines are is presented, in which maximum displacement response to design earthquake motion is used as the limit-state design criteria. A method of estimating dynamic response displacement of the structures based on static nonlinear analysis is described. A theoretical estimation of nonlinear dynamic response considering the characteristics of energy input to the system is described in detail, which may be used as the standard method in the new performance-based code. A desing philosophy not only satisfying the criteria but also evaluating seismic capacity of the structures is also introduced.

• Wind and Structures
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• v.13 no.3
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• pp.221-234
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• 2010

In light-frame wood construction, missing roof-sheathing fasteners can be a relatively common occurrence. This type of construction makes up the vast majority of the residential building stock in North America and thus their performance in high winds, including hurricanes, is of concern due to their sheer number. Construction quality issues are common in these types of structures primarily because the majority are conventionally constructed and unlike steel and reinforced concrete structures, inspection is minimal except in certain areas of the country. The concept of performance-based wind engineering (PBWE), a relatively new paradigm, relies on the assumption that building performance under wind loads can be accurately modeled. However, the discrepancy between what is designed (and modeled) and what is built (the as-built) may make application of PBWE to light-frame wood buildings quite difficult. It can be concluded from this study that construction quality must be controlled for realistic application of PBWE to light-frame wood buildings.

• Korean Security Journal
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• no.23
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• pp.109-131
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• 2010

This research analyzed how the new and senior security guards employed privately are influenced on their task performance by the factors operated before task performance: cognitive state anxiety, physical state anxiety and state confidence which are the sub-factors of the Competitive State Anxiety(CSAI-II) according to the educational background, career, gender and athletic capacity. First, as for the new and senior security guards' state anxiety before task performance, the senior guards felt the cognitive anxiety more than the new guards, but there was not a distinct difference statistically. Therefore, it is estimated that there is little difference in the level of cognitive anxiety between the new security guards with insufficient career and the seniors. Second, the level of the physical state anxiety was shown higher from the senior guards than from the new ones and had a distinct difference. However, it seems to be derived from the extent of physical development as the seniors are at the time of vigorous physical development. Third, the level of state anxiety had no distinct difference between them statistically though the new security guards felt it higher than the seniors. Fourth, the state confidence was shown higher from the seniors than from the new and had a distinct difference statistically, also. Fifth, as for gender, the male and female guards did not have a difference so much in the cognitive and physical state anxiety, and state confidence. Sixth, as a whole, the state anxiety was highest as for the security guards with athletic capacity level 1 and 2. Those with the level 2, and 3 and the level above 7 felt it less than those with the level 5-6, which had a distinct difference in statistics. The manager of the new and senior security guards should make them dispel anxiety in piece of mind through physical and mental education encouraging them to have self-confidence, practical training, and psychological training based on the analysis of causes of various cases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.2
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• pp.872-877
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• 2011

In this paper, the new decoding algorithm of Block Turbo Codes using Channel State Information(CSI), which is estimated to compensate for the distorted signal caused by multi-path fading, is proposed in order to improve error correction capacity during decoding procedure in OFDM system. The performance of the new decoding algorithm is compared to that of the conventional decoding algorithm without using channel state information under the Rayleigh fading channel. Experimental results showed that in case of only one iteration coding gains of up to 5.0dB~9.0dB can be obtained by applying the channel state information to the conventional decoding algorithm according to the modulation methods. In addition to that, the new decoding algorithm using channel state information at only one iteration shows a performance improvement of 3.5dB to 5.0dB when compared to the conventional decoding algorithm after four iterations. This leads to reduce the considerable amount of computation.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.5
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• pp.612-619
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• 2015

Current study aimed to evaluate the performance of bulls (1/2 Purun$\tilde{a}$ vs 1/2 Canchim) slaughtered at two ages and three different weights. One hundred and thirteen bulls were divided into two slaughter ages (16 and 22 months) and three different slaughter weights (light, 422 kg; medium, 470 kg; and heavy, 550 kg). The body weight was higher for bulls slaughtered at 16 months. Daily gain, carcass weight and dressing were higher for bulls slaughtered at 16 months. Feed intake was higher for bulls slaughtered at 22 months although feed efficiency was better for bulls slaughtered at 16 months. Carcass characteristics were better for bulls slaughtered at 16 months. The percentages of muscle, fat and bone and meat characteristics were similar between two slaughter ages. Feed intake and animal performance was lower for lighter animals. Feed conversion and carcass dressing were similar in the three slaughter weights. Muscle percentage was higher for heavier animals but fat and bone percentages were lower. Slaughter weight had no effect on meat characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.3
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• pp.408-415
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• 2013

The objective of this experiment was to assess the use of different vitamin D metabolites in the feed of broiler chickens and the effects of the metabolites on performance, bone parameters and meat quality. A total of 952 one-day-old male broiler chicks were distributed in a completely randomised design, with four treatments, seven replicates and 34 birds per experimental unit. The treatments consisted of four different sources of vitamin D included in the diet, $D_3$, $25(OH)D_3$, $1,25(OH)_2D_3$, and $1{\alpha}(OH)D_3$, providing 2000 and 1600 IU of vitamin D in the starter (1 to 21 d) and growth phases (22 to 42 d), respectively. Mean weight, feed:gain and weight gain throughout the rearing period were less in animals fed $1{\alpha}(OH)D_3$ when compared with the other treatments (p<0.05). No significant differences were noted among the treatments (p>0.05) for various bone parameters. Meat colour differed among the treatments (p>0.05). All of the metabolites used in the diets, with the exception of $1{\alpha}(OH)D_3$, can be used for broiler chickens without problems for performance and bone quality, however, some aspects of meat quality were affected.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.3
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• pp.410-416
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• 2017

Objective: This study was to evaluate the sunflower cake and enzymatic complex fed to broilers from 22 to 42 d of age. Methods: In a completely randomized design, a total of 850 birds were allotted in a $2{\times}5$ factorial scheme (with and without enzymatic complex) and five inclusion levels (0%, 5%, 10%, 15%, 20%) of sunflower cake. There were 5 replications and 17 birds in each experimental unit. Data from performance, carcass yield and intestinal morphology were evaluated. Results: Feed intake, weight gain, final weight and feed:gain ratio linearly worsened as sunflower cake increased. For weight gain, final weight and feed:gain ratio, the birds whose diets contained levels of 15% and 20% of sunflower cake showed worse values (p<0.05) than the birds fed the control diet. When fed the enzymatic complex, birds improved (p<0.05) crypt depth and villus:crypt ratio in the jejunum. As inclusion levels of sunflower cake increased, villus depth and villus:crypt ratio in duodenum, jejunum and ileum linearly reduced and the crypt depth linearly increased. Carcass yield linearly reduced as sunflower cake increased. Conclusion: Based on performance, sunflower cake can be used up to 10% in broilers feeding from 21 to 42 days of age.

• Journal of Electrochemical Science and Technology
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• v.13 no.3
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• pp.362-368
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• 2022

The application of polymer composite electrolyte in all-solid-state lithium-sulfur battery (ASSLSBs) can guarantee high energy density and improve the interface contact between electrolyte and electrode, which has a broader application prospect. However, the inherent insulation of the sulfur-cathode leads to a low electron/ion transfer rate. Carbon materials with high electronic conductivity and electrolyte materials with high ionic conductivity are usually selected to improve the electron/ion conduction of the composite cathode. In this work, PEO-LiTFSI-LLZO composite polymer electrolyte (CPE) with high ionic conductivity was prepared. The ionic conductivity was 1.16×10^-4 and 7.26×10^-4 S cm^-1 at 20 and 60℃, respectively. Meanwhile, the composite sulfur cathode was prepared with Sulfur, reduced graphene oxide and composite polymer electrolyte slurry (S-rGO-CPEs). In addition to improving the ion conductivity in the cathode, CPEs also replaces the role of binder. The influence of different contents of CPEs in the cathode material on the performance of the constructed battery was investigated. The results show that the electrochemical performance of the all-solid-state lithium-sulfur battery is the best when the content of the composite electrolyte in the cathode is 40%. Under the condition of 0.2C and 45℃, the charging and discharging capacity of the first cycle is 923 mAh g^-1, and the retention capacity is 653 mAh g^-1 after 50 cycles.