• Asian-Australasian Journal of Animal Sciences
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• v.27 no.9
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• pp.1293-1302
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• 2014

The aim of study was to determine the energy requirements for maintenance and growth of forty-one Saanen, intact male kids with initial body weight (BW) of $5.12{\pm}0.19$ kg. The baseline (BL) group consisted of eight kids averaging $5.46{\pm}0.18$ kg BW. An intermediate group consisted of six kids, fed for ad libitum intake, that were slaughtered when they reached an average BW of $12.9{\pm}0.29$ kg. The remaining kids (n = 27) were randomly allocated into nine slaughter groups (blocks) of three animals distributed among three amounts of dry matter intake (DMI; ad libitum and restricted to 70% or 40% of ad libitum intake). Animals in a group were slaughtered when the ad libitum-treatment kid in the group reached 20 kg BW. In a digestibility trial, 21 kids (same animals of the comparative slaughter) were housed in metabolic cages and used in a completely randomized design to evaluate the energetic value of the diet at different feed intake levels. The net energy for maintenance ($NE_m$) was $417kJ/kg^{0.75}$ of empty BW (EBW)/d, while the metabolizable energy for maintenance ($ME_m$) was $657kJ/kg^{0.75}$ of EBW/d. The efficiency of ME use for NE maintenance ($k_m$) was 0.64. Body fat content varied from 59.91 to 92.02 g/kg of EBW while body energy content varied from 6.37 to 7.76 MJ/kg of EBW, respectively, for 5 and 20 kg of EBW. The net energy for growth ($NE_g$) ranged from 7.4 to 9.0 MJ/kg of empty weight gain by day at 5 and 20 kg BW, respectively. This study indicated that the energy requirements in goats were lower than previously published requirements for growing dairy goats.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.4
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• pp.107-115
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• 2012

The present study evaluates the validity of different equations specified in code provisions and proposed by the existing researchers to predict the concrete tensile capacities (direct tensile strength, splitting tensile strength and modulus of rupture) using a comprehensible database including 361 lightweight concrete (LWC), 1,335 normal-weight concrete (NWC) and 221 heavy-weight concrete (HWC) specimens. Most of the equations express the concrete tensile strengths as a function of its compressive strength based on the limited NWC concrete test data. However, the present database shows that the concrete tensile capacities are significantly affected by its unit weight as well. As a result, the inconsistency between experiments and predictions by the different models increases when the concrete unit weight is below 2,100 kg/$m^3$ and concrete compressive strength is above 50 MPa. On the other hand, new models proposed by the present study considering the concrete unit weight predict the tensile strengths of concrete with more accuracy.

• Journal of Applied Reliability
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• v.16 no.4
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• pp.280-286
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• 2016

Purpose: Recently, Jiang defines the tradeoff B life to minimize a sum of life lost by preventive maintenance (PM) and corrective maintenance (CM) contribution parts and sets up an optimal replacement age of age replacement policy as this tradeoff life. In this paper, Jiang's model only considering the known lifetime distribution is extended by assigning different weights to two parts of PM and CM in order to reflect the practical maintenance situations in application. Methods: The new age replacement model is formulated and the meaning of a weight factor is expressed with the implied cost of failure under asymptotic expected cost model and also discussed with one-cycle expected cost criterion. Results: The proposed model is applied to Weibull and lognormal lifetime distributions and optimum PM replacement ages are derived with corresponding implied cost of failure. Conclusion: The new age replacement policy to escape the estimation of cost of failure in classical asymptotic expected cost criterion based on the renewal process is provided.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.235-240
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• 2008

Since urban railway transit is one of the most essential transportation systems, its power facilities must ensure high reliability and safety. Currently, urban railway operating organizations perform TBM (Time Based Maintenance) on power facilities. However, in order to improve management efficiency and system safety, CBM (Condition Based Maintenance) is preferred. Among various power facilities, mold transformers has been chosen as the object of study since it is widely used for the purpose of minimizing volume and weight, and due to safety against fire. In this paper, various transformer failure cases due to electric, thermal, mechanical and environmental factors have been collected and analyzed. In addition, investigation on national and international condition based maintenance cases and the characteristics of sensors widely used for transformer monitoring has been performed to suggest the optimal condition based maintenance technique for urban railway systems.

• Structural Monitoring and Maintenance
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• v.10 no.2
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• pp.175-190
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• 2023

This article aims to quantitatively predict the snowmelt in extreme cold regions, considering a combination of grayscale and neural models. The traditional non-equidistant GM(1,1) prediction model is optimized by adjusting the time-distance weight matrix, optimizing the background value of the differential equation and optimizing the initial value of the model, and using the BP neural network for the first. The adjusted ice forecast model has an accuracy of 0.984 and posterior variance and the average forecast error value is 1.46%. Compared with the GM(1,1) and BP network models, the accuracy of the prediction results has been significantly improved, and the quantitative prediction of the ice sheet is more accurate. The monitoring and maintenance of the structure by quantitative prediction model by gray models was clearly demonstrated in the model.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.9
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• pp.1397-1406
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• 2019

Objective: Feed energy required for pigs is first prioritized to meet maintenance costs. Additional energy intake in excess of the energy requirement for maintenance is retained as protein and fat in the body, leading to weight gain. The objective of this study was to estimate the metabolizable energy requirements for maintenance ($ME_m$) by regressing body weight (BW) gain against metabolizable energy intake (MEI) in growing pigs. Methods: Thirty-six growing pigs ($26.3{\pm}1.7kg$) were allotted to 1 of 6 treatments with 6 replicates per treatment in a randomized complete block design. Treatments were 6 feeding levels which were calculated as 50%, 60%, 70%, 80%, 90%, or 100% of the estimated ad libitum MEI ($2,400kJ/kg\;BW^{0.60}\;d$). All pigs were individually housed in metabolism crates for 30 d and weighed every 5 d. Moreover, each pig from each treatment was placed in the open-circuit respiration chambers to measure heat production (HP) and energy retained as protein ($RE_p$) and fat ($RE_f$) every 5 d. Serum biochemical parameters of pigs were analyzed at the end of the experiment. Results: The average daily gain (ADG) and HP as well as the $RE_p$ and $RE_f$ linearly increased with increasing feed intake (p<0.010). ${\beta}$-hydroxybutyrate concentration of serum tended to increase with increasing feed intake (p = 0.080). The regression equations of MEI on ADG were MEI, $kJ/kg\;BW^{0.60}\;d=1.88{\times}ADG$, g/d+782 ($R^2=0.86$) and $ME_m$ was estimated at $782kJ/kg\;BW^{0.60}\;d$. Protein retention of growing pigs would be positive while REf would be negative at this feeding level via regression equations of $RE_p$ and $RE_f$ on MEI. Conclusion: The $ME_m$ was estimated at $782kJ/kg\;BW^{0.60}\;d$ in current experiment. Furthermore, growing pigs will deposit protein and oxidize fat if provided feed at the estimated maintenance level.

• Journal of Preventive Medicine and Public Health
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• v.16 no.1
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• pp.105-112
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• 1983

To characterize the diet and physical exercise patterns of bank personnel for the health maintenance, a questionnaire was administered to all the employess (1,249) of Daegu Bank in June 1983 among whick 78.1% (976) responded. Three quarters of the respondents were between 20 and 34 years old. About 30% of 20-24 years old group were male compared with 73.1% of 25-39 years old group. Major findings of the survey are as follows: 1) The most concerned chronic disease of the respondents were in the order of cancer (27.4%), psychiatric disease (15.1%), hypertension (14.1%), heart disease (13.7%) and tuberculosis (7.9%). 2) For the prevention of adulthood disease and obesity, 53.4% of the respondents were restricting sugar intake; 40.9%, salt: and 35.1%, fat-rich food. 3) Among all the respondents 36.9% were making effort to reduce body weight and 17.7% were trying to gain body weight. 4) The proportion of respondents who practice physical exercise for the health maintenance was 82.9% in male and 62.5% in female.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.3
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• pp.277-283
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• 1997

Purified diets containing five levels of methionine with 0.4% cystine were fed to growing chicks (8 days old male Arbor Acre strain) to evaluate methionine requirements for growth and maintenance. A model was developed to separate methionine requirement for maintenance from requirement for growth. From this model the daily methionine requirement for growth was 4.22 mg/g gain, and the daily methionine requirement for maintenance was 0.034 times metabolic body size ($W^{0.75}$). Based on nitrogen gain response, the methionine requirement for growth was 0.162 mg/mg N gain, and the daily maintenance requirement was 0.037 times metabolic body size. The plateau of plasma methionine concentration reached at 117.16 mg intake pre day. The total methionine requirement determined based on weight gain response was 138.29 mg/day or 0.33% of the diet and the one determined based on nitrogen gain response was 141.7 mg/day of 0.34% of the diet, respectively. As a percentage of protein, methionine was calculated to be 2.6%; the reported methionine content of carcass CP was 1.76%.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.3
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• pp.211-220
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• 2002

CGS(Compaction Grouting System) is widely used in reinforcement of structural foundation and ground improvement in soft ground. But the effects of ground improvement depending on the type of soil must be studied in order to adopt in various soils (granular soil and cohesive soil). In this study, characteristics of ground improvement (the increase of N value, increase in unit weight, vertical displacement on the ground surface) by CGS method was compared through two cases that were performed in granular and cohesive soil. The results show that the closer to the grout hole, the more increase in N value and this trend appear distinctly in granular soil. Unit weight of ground increase largely near by the grout hole and decrease in far from it independently of the soil type. The vertical displacement on the ground surface appeared in smaller area in case of granular soil than cohesive soil.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.3
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• pp.149-156
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• 1999

Numerical studies were carried out to investigate the mechanical properties of competent hysteric isolators for seismic design of bridge. For dynamic analysis, bridges with isolator were simplified to a model with single degree of freedom. The initial stiffness and the yielding forces of hysteric isolators were varied. Seismic responses obtained by time history analysis show that about 4% of the weight acting as the inertia force is appropriate for the yielding force of isolator. And also better results could be achieved with the values about two times the weight per unit displacement for the initial stiffness of isolator.