• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.4
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• pp.211-218
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• 2000

Many bridges are severely damaged by the overloaded heavy vehicle and the trend will become more serious because the traffic volume is continuously increasing. Currently, the vehicles with gross weights over 40 tonf or axle weight over 10 tonf are not allowed on the public road. However, this regulation is not based on a systematic study on the bridge capacity and assumed to be much too conservative depending on the vehicle types and bridge types. In this study, the permit weights of heavy vehicles of diverse axle spacings and axle load distribution are calculated considering the structural characteristics of bridge superstructures. In order to consider the various load effects of heavy weight vehicle crossings, three conditions are considered in the calculation of permit vehicle load. From the results, the permit vehicle weights of the simple girder bridges are calculated.

• Journal of Nutrition and Health
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• v.25 no.3
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• pp.256-263
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• 1992

As various metabolic alterations develope in uremic patients. their diets need to be restricted, Furthermore medical complications with accompanying anorexia result in further complications and decrease in body strength. To assess the nutritional status of hemodialyzed patients we performed evaluation for dietary intake and protein catabolic rate(PCR) For 24 clinically stable male patients undergoing maintenance hemodialysis dietary intake was estimated by 3-day food record method and PCR was calculated with blood urea nitrogen at pre and post hemodialysis. The results were as follows : 1) Average daily energy and protein intake were 26.7$\pm$5.1kcal/kg of body weight. 0.95$\pm$0.19 g/kg of body weight respectively. 2) Protein catabolic rate calculated from interdialysis blood urea nitrogen levels was 1.00$\pm$0.20g/kg of body weight. Protein catabolic rate was correlated with the amount of Protein intake(r=0.44 p<0.05) 3) Relative body weight(RBW) of the subjects was smaller than that of healthy man without hemodialysis. Calorie and protein intake and protein catabolic rate were significantly different (p<0.05) between patients with lower RBW(<90% of ideal body weight) and those with normal RBW(90~110% of ideal body weight) and those with normal RBW(90~110% of iedal body weight) 4) The duration of hemodialysis did not have a significant effect on the nutritional status of the subjects.

• Journal of the Korean GEO-environmental Society
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• v.19 no.2
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• pp.37-44
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• 2018

Ballasted track has been widely used due to its flexibility. However, the plastic deformation of ballasted track causes the evolution of track geometrical errors, and hence it requires continuous maintenance; increase in number of trains, weight, and speed expedites maintenance frequency and cost as well. Ballast stiffness is well-known as an indicator of design and maintenance. In this regard, this paper aims to suggest the method to measure ballast track stiffness using light-weight deflectometer (LWD) and thus verify its applicability as a maintenance measure. Preliminary field tests determined simple field testing protocol to measure track stiffness. The apparent ballast stiffness by LWD shows good corelation with TQI (Track Quality Index) and maintenance length. That is, as average of apparent stiffness increase, TQI and tamping length decrease exponentially. Therefore, apparent stiffness can be used as an index for ballast condition assessment.

• International Journal of Highway Engineering
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• v.16 no.4
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• pp.11-19
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• 2014

PURPOSES: This study is to suggest the improvement for bus rapid transit system in Seoul METHODS: The maintenance cost for bus lane damages and plastic deformations are increased by bus passing speed, heavy bus weight, and climate change (localized torrential downpour, subtropical climate) and the accident risk has been increased. RESULTS: Recent analysis of pavement damage indicates that bus lane damage caused by heavy weight is overwhelming and it is urgent to prepare countermeasures. CONCLUSIONS : Pavement data of bus rapid transit system, bus transit numbers and pavement damage elements were analyzed. By analyzing pavement maintenance, design and construction, the countermeasures for the improvement of bus lane pavement and effective maintenance were suggested.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.63-64
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• 2022

Inter-floor noise in an apartment building is a serious problem that causes conflicts between tenants. Accordingly, there are various attempts to solve this problem, but it is not easy to find a clear solution. Therefore, in this study, a soundproofing material between floors was developed that can improve the sagging that occurs after construction. And as a result of testing the developed interlayer soundproofing material, both light weight and weight were grade 1. And it was analyzed that maintenance performance could be improved with integrated structural characteristics.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.2
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• pp.111-123
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• 2006

In the design of bridges, exact evaluation of traffic loading is very important for the safety and maintenance of bridges. In general, traffic loading is represented by live load (including impact load) and fatigue load. For exact evaluation of traffic loading, it is important to get reliable and comprehensive truck data including the traffic and weight information. It requires the development of Bridge Weigh-In-Motion (BWIM), which measures the truck weights without stopping the traffic. Objectives of the study is (1) to develop the BWIM system, (2) to verified the system in bridges in Highways.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1782-1788
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• 2003

A mathematical model has been constructed to estimate the amino acid requirements for growing Taihe silky fowls in early stage. A requirement was taken as the sum of the needs for maintenance, for gain in carcass weight without feathers, and for the feathers. The maintenance requirement was considered to be the sum of the needs for replacing skin and intestinal losses and for the obligatory creatinine excretion in the urine. A comparative slaughter trial and nitrogen balance trials with growing and adult Taihe silky fowls, respectively, were conducted to estimate the parameters in the model. The amino acid requirements were then calculated with the constructed models. The results showed as following: the replacement needs for skin nitrogen loss was determined at 213.41 mg/d for adult male fowls (body weight 1.60 kg); creatinine excretion in these birds was 4.04 mg/d. when fed an nitrogen-free diets, the adult male fowls with body weight 1.60 kg excreted a total of 246.10 mg/d endogenous nitrogen. The net protein requirement for maintenance was estimated at $11.24mg/w_g{^{0.75}}/d$Per gram of body weight gain contained 27.18 mg carcass nitrogen for growing birds in early stage, but feathers nitrogen in per gram of body weight gain increased with age. The amino acid requirements for growing Taihe silky fowls were slightly higher than for starting and growing pullets, but lower than that of broiler chicks. The amino acid requirements patterns changed with weeks of age.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.2
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• pp.85-89
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• 1990

Sixteen Harnai lambs were used in a completely randomized design to study the nutritive value of fourwing saltbush as a winter maintenance browse in comparison to native range grazing with or without protein and energy supplementation at Tomagh Range Livestock Research Station, in Loralai District, Balochistan. The animals were divided into four groups of four lambs each. These four groups were assigned four treatments at random: fourwing saltbush grazing alone, range grazing plus lucerne hay (100 g/head/day), range grazing plus barley grain (100 g/head/day) and range grazing alone for ten weeks. The results indicate that the two range grazing plus supplementation treatments produced weight gains which were not significantly different from each other (p < 0.05). Both of these treatments yielded significantly higher weight gains (p < 0.05) than did range grazing alone except for the last week of the study. Fourwing saltbush grazing provided cumulative weight gains at 3, 4, 6, 7 and 8 weeks which were not significantly different from the range grazing plus lucerne hay treatment and gained an average of 6 percent in body weight over the 10 week period of study. The carrying capacity for sheep of a mature stand of fourwing saltbush was approximately 20 Sheep-kg-days (SKD) of grazing per cubic meter of foliage. Results of this study suggest that under fourwing saltbush grazing alone, lambs do not only maintain their body weights but can also gain weight in winter.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.2
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• pp.7-13
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• 2011

Turbine journal bearings are designed to support the weight of the rotors on a hydrodynamic oil film and to provide dynamic stability to the rotor system. The life time of journal bearings is infinite theoretically because the journal bearings are separated from the shaft journal by oil film. But poor design, assembly, operation and maintenance can cause problems to the journal bearings. The FMEA(Failure Mode and Effects Analysis) results of the journal bearings show that frequent maintenance of the journal bearings can cause failures and reduction of the bearing life. Therefore, the maintenance periods and history of the journal bearings with the bearing FMEA results are reviewed in order to establish the optimized maintenance period of the journal bearing for the nuclear power plants. Consequently it is necessary to maintain a best condition of lubrication system, reject time-based maintenance and perform the condition-based maintenance of journal bearings in order to maintain optimum condition of the journal bearing.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1359-1370
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• 2008

In the track geometry such as rails, sleepers, ballasts and fastener, track deterioration occurs by repetitive train weight and the high-speed railway takes a trend faster than normal. Track deterioration of over threshold value harms ride comfort and furthermore affect in trains safety seriously. An organic and systematic track maintenance system is very important because a trend of the track deterioration effects on track life-cycle and running safety. Also costs of the railway track permanent way and its maintenance are extremely large, forming a significant part of the total infrastructure expenditure. Therefor reasonable and efficient track maintenance has to be planed on a budget. It is required to carry out not only corrective maintenance but preventive maintenance for the track maintenance. In order to perform maintenance jobs in the boundary of the machines and resources given regarding the type and amount jobs, it is necessary to determine feasible or optimal scheduling considering the priority. In this study, the system organization and required functions for the development of track maintenance system supported track deterioration prediction and optimal scheduling are proposed.