• International Journal of Highway Engineering
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• v.12 no.3
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• pp.17-26
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• 2010

Maintenance of the roads and bridges is a major issue for all road administrators around the world, and various initiatives are being implemented in each region for the purpose of controlling the ever increasing road maintenance cost while ensuring the safety of the vehicles driving. Efforts for such initiatives have also been made in Asia and initiatives for managing heavy-weight vehicles have recently gained momentum in Korea and Japan. We have developed a technology for unevenly installing bar-shaped sensors (piezo quartz sensors) to enable dynamic axle load measurement at a highly accurate level, and have estimated our measurement accuracy of axle load/gross weight, etc. on an actual road. The measurement accuracy of the axle load/gross weight varies significantly depending on the number of sensors installed. In our implementation, the target accuracy was set to below ${\pm}5%$ for gross weight measurement so that automatic regulation can be applied. We have achieved our target by installing 8-point measurement system. However, to have this technology widely accepted, it was necessary to reduce the system size so that it can be easily implemented. Therefore, we have estimated the relationship between the measurement accuracy and the system size (number of measurement points), and have come up with the proposal of 3-point measurement as an optimum number of measurement points, and have estimated its performance on an actual road. Additionally, we evaluated the relationship between the measurement accuracy and vehicle velocity.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.221-221
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• 2015

Sustainable use of water resource and conservation of water quality are essential problems in the world. Especially, problems of water quality are serious one for human health as well as ecological system of all creatures on the earth. Recently, the importance of total effluent load as well as the concentrations of pollutant materials has been recognized not only for the conservation of water quality but also for sustainable water use in watersheds. However, the measurement or estimation of total effluent load from non-point source area such as farm lands or forests may be more difficult because both of concentration and discharge of the water are greatly changed depending on various factors especially metrological conditions such as rainfall, while the measurement from a point source area may be easy because the concentration of pollutant materials and amount of discharge water are relatively steady. Therefore, the total effluent load from a non-point source is often estimated by statistical relationships between concentration and discharge, which is called as L-Q equation. However, a lot of work and time are required to collect and analyze water samples and to get the accurate relationship or regressive equation. So, we proposed a new system for direct measurement of total effluent load of water quality from non-point source areas to solve the problem. In this system, the overflow depth at a hydraulic weir is measured with a pressure gage every hourly interval to calculate the amount of hourly discharge at first. Then, the operating time of a small electric pump to collect an amount of water which is proportional to the discharge is calculated to intake the water into a storage tank. The stored water is taken out a few days later in a case of storm event or several weeks later in a case of non-rainfall event and the concentrations of water quality such as total nitrogen and phosphorous are analyzed in a laboratory. Finally, total load of the water quality can be calculated by multiplying the concentration by the total volume of discharge. The system was installed in a small experimental forestry watershed to check the performance and know the total load of water quality from the forest. It was found that the system to collect a proportional amount of water to actual discharge operated perfectly and a total load of water quality was analyzed accurately. As the result, it was expected that the system will be very available to know the total load from a non-point source area.

• Structural Monitoring and Maintenance
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• v.9 no.4
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• pp.323-336
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• 2022

Steel truss bridge is one of the most widely used bridge types in Indonesia. Out of all Indonesia's national roads, the number of steel truss bridges reaches 12% of the total 17,160 bridges. The application of steel truss bridges is relatively high considering this type of bridge provides advantages in the standardization of design and fabrication of structural elements for typical bridge spans, as well as ease of mobilization. Directorate of Road and Bridge Engineering, Ministry of Works and Housing, has issued a standard design for steel truss bridges commonly used in Indonesia, which is designed against the design load in SNI 1725-2016 Bridge Loading Standards. Along with the development of actual traffic load measurement technology using Bridge Weigh-in-Motion (B-WIM), traffic loading data can be utilized to evaluate the reliability of standard bridges, such as standard steel truss bridges which are commonly used in Indonesia. The result of the B-WIM measurement on the Central Java Pantura National Road, Batang - Kendal undertaken in 2018, which supports the heaviest load and traffic conditions on the national road, is used in this study. In this study, simulation of a sequences of traffic was carried out based on B-WIM data as a moving load on the Australian type Steel Truss Bridge (i.e., Rangka Baja Australia -RBA) structure model with 60 m class A span. The reliability evaluation was then carried out by calculating the reliability index or the probability of structural failure. Based on the analysis conducted in this study, it was found that the reliability index of the 60 m class Aspan for RBA bridge is 3.04 or the probability of structural failure is 1.18 × 10^-3, which describes the level of reliability of the RBA bridge structure due to the loads from B-WIM measurement in Indonesia. For this RBA Bridge 60 m span class A, it was found that the calibrated nominal live load that met the target reliability is increased by 13% than stated in the code, so the uniform distributed load will be 7.60 kN/m² and the axle line equivalent load will be 55.15 kN/m.

• Proceedings of the KIEE Conference
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• 2002.06a
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• pp.79-82
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• 2002

Non-linear loads are the sources of power systems harmonics, and the power quality is influenced by harmonics, Recently, the requirements of power quality is important. For the power quality problems. it is very important that the development of power measurement circuit for non-linear load. In this paper, it is discoursed on that high speed sampling circuit and efficient power analysis algorithms. The sampling circuit is implemented using FPGA. Since the power measurement circuit system is composed by FPGA and efficient power algorithms. it is practicable application that accurate power measurement, stable protection relaying, and low cost system configuring.

• Journal of Sensor Science and Technology
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• v.13 no.1
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• pp.1-11
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• 2004

Due to various types of errors added to dynamic weight measurement data, proper methods to reduce measurement errors are required to produce reliable weights. To cope with parasitic types of errors in real systems, information provided by the various sensors is utilized and combined in such a way to reduce the measurement errors of load cells. In addition to four channels of load cells from a trailer, an accelerometer is used to obtain the information to compensate the error induced from vertical movement of the vehicle due to the variation of ground level. A model trailer system is run to verify the effectiveness of the proposed method to reduce noise of dynamic weight measurements. Experiments show that the processed error magnitudes of less than 20 g can be obtained for 10 Kg experimental loads.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.325-327
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• 1999

In this research, selection of component load and measurement device is considered for accurate component load modeling. The procedure of component load characteristic experiments is also presented.

• Journal of Biosystems Engineering
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• v.32 no.3
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• pp.190-196
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• 2007

The purpose of this study is to develop a measurement system of cutter conditions for combine header diagnosis during rice harvesting. A load cell was installed at the locker-arm to measure load fluctuation and an acceleration senor was used to monitor vibration signal of cutter bar. The data were collected from a paddy field during harvesting. The tests were conducted with a normal cutter, a loosened cutter, a broken cutter, and a worn-out connecter pin at the field. The vibration signals converted by FFT (Fast Fourier Transformation), filtered, and normalized. The load data and peak values of vibration signals in four different frequency ranges were used to determine the cutting operation and the cutter conditions of combine. The multiple comparison tests showed that the load data and peak values of vibration signals were important to monitor the cutting operation and cutter conditions of combine header.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.4
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• pp.75-81
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• 2012

In this study, vibration characteristics in according to the load type of cast resin transformer using vibration measurement device were compared. Measurement conditions are the same installation and operation of the three-phase cast resin transformer. If the load increases in transformer using the rotating machinery, the frequency is growing. In the transformer using the lighting and heating loads, it's detected the 55 [${\mu}m/s$] in or outside and 120 [${\mu}m/s$] or more at 60[Hz], the 30 [${\mu}m/s$] in or outside at 120[Hz], and the 70 [${\mu}m/s$] in or outside at 420[Hz]. When increases the loads, it's appeared the 60 [${\mu}m/s$] or less at 450[Hz] or more in rotating machinery, but the velocity of lighting and lighting loads are appeared from 5[${\mu}m/s$] to 115[${\mu}m/s$] inside the 420[Hz] in the same load condition of 20[%]. Through this study, it's verified that there are differences the internal vibration in according to the type of load in cast resin transformer.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.116-118
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• 2004

This paper gives a measurement data of the feeder demand factor in small size apartments. The power load measurement data of the feeder shows that the feeders have $10{\sim}30[%]$ margin in capacity. But this margin is not enough to keep up with the trend of power consumption increase from long term standpoint. So it is necessary to measure the feeder power load periodically for the purpose of optimal feeder capacity estimation

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.12
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• pp.1088-1094
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• 2003

Case study was peformed to analyze energy load for department stores and develop energy load model to be applied to a cogeneration system. Energy loads of 14 departments were analyzed based on energy load sheets written by operators and energy load of one department store was measured through modem communication for a year. Energy load of department stores shows various variations depending on when they are opened or closed and, hours, days and months. In this paper, the measurement was compared with data in energy load sheets and resolved, and energy load model for a department store was built. It is important to use an accurate energy load model for an accurate feasibility study applying a cogeneration system to buildings.