Jo Nov 10, 2026
Energy audit compares energy consumption and energy efficiency of different enterprises in the same industry by investigating the overall energy consumption, energy consumption increase, energy consumption per unit of product, etc.
The aim of energy audit is to find a real energy saving solution, to create new ideas, and to prepare energy management improvements while saving costs.
To achieve this goal, it is very important to set up detailed audit indicators and, on this basis, to perform detailed audit on each indicator.
To Sang Il, a researcher at the Faculty of Industrial Economic Management, established general and detailed energy audit indicators for industrial enterprises and proposed a standard energy audit method based on them.
First of all, he set indicators in terms of energy utilization technology, energy management method, energy self-production and energy environmental impact. Based on the indicators, he proposed a method of conducting the survey and analysis of energy use of industrial enterprises. Then, he used the attribute hierarchy model (AHM) and the entropy method to determine the weights of evaluation indicators and to comprehensively evaluate the energy use level. After that, he proposed a method to identify improvement measures by prioritizing the alternatives.
For more information, please refer to his paper “Energy Auditing Method for Industrial Enterprises” in “Proceedings of KUTIC-2025”.
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Jo Nov 9, 2026
A separate type thermosyphon is a two-phase device with extremely high effective thermal conductivity that utilizes the thermodynamic pressure difference that develops between the evaporator and the condenser to circulate working fluid through a closed loop. With long-distance heat transport capability unlike traditional heat pipes, SHPs have been widely utilized in difference areas.
Based on the analysis of preceding research papers, Pak Yong Nam, a researcher at the Faculty of Thermal Engineering, proposed a novel separate type thermosyphon with a jacketed condensation section and conducted a theoretical study of the installation height of evaporation and jacketed condensation sections.
He considered the installation height of evaporation and jacketed condensation sections while varying the input heat under 150W. The results indicate that the installation height rises with the increase in the input heat and the installation height may be 30cm under the input of 150W.
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Jo Nov 8, 2026
With the increasing availability of computer networks and the ever-increasing demand for network security, it is important to ensure confidentiality and reduce computational costs in access to databases.
Access control encryption plays a key role in ensuring confidentiality of databases and efficient management of computer networks. There has been active research on access control encryption, which has resulted in various modes and kinds. Particular intensity has been directed to the attribute-based encryption, which combines attribute-based access control model and encryption scheme, and many approaches have been proposed to improve security and efficiency for different applications.
Pak Su Ryon, a researcher at the Faculty of Information Science and Technology, has proposed an attribute-based multilayer access control scheme, which has 3 layers of attributes for performing different functions, with a purpose to ensure confidentiality and access control efficiency and to reduce computational cost.
The validity result of the effectiveness of the proposed method shows that the time of access control is reduced by less than 70% and the system ensures the confidentiality of databases while providing partial access to them and enables the system manager and the data owner to control access together.
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Jo Nov 6, 2026
The frequency is an important operating parameter of power systems and electrical equipment, and the frequency measurement is the basis of the operation and monitoring of power systems and electrical equipment and of relaying protection. The frequency of power systems is an important index of power quality, and it is very important for the fault diagnosis of power systems. Larger power system capacity increases the stability requirement of power systems, which consequently leads to higher measurement accuracy of the frequency of power systems.
Many frequency measurement theories and calculation methods have been developed so far. Although they can be used in real applications with relatively accurate frequency measurements and small measurement errors, they are all based on discrete Fourier transform (DFT) under asynchronous samples, and approximate computational methods have been employed for real frequency measurement calculations.
Im Jung Bin, a researcher at the Faculty of Electrical Engineering, used vector theory to accurately measure the frequency under asynchronous sampling conditions for sinusoidal signals with constant frequency offset. He proposed a frequency measurement principle based on the vectors at three sampling points and calculated the frequency based on the calculation of the real and imaginary parts at each sampling point using DFT transform. Likewise, he proposed a frequency calculation method under asynchronous sampling and verified through simulation that the frequency measurement method under asynchronous sampling using three sampling values is accurate.
This provides a method for accurately and quickly measuring the frequency in the development of power measuring devices and protective devices.
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Jo Nov 5, 2026
The reliability problems of shock tube initiation systems have been a focus in mining and demolition blasting. Current blasting practices widely use shock tubes as a non-electrical initiation means. Shock tube initiation systems typically consist of shock tubes coupled with a donor detonator. Shock tubes are used to transmit an initiation impulse to the target detonators. The shock tubes are initiated and detonated by the adiabatical pressing of the mixture of explosive material and air due to the explosion shock by detonators.
Reliability is the most important for any initiation system, and efficient initiation of shock tubes is an important factor.
There has been some research on initiating a bunch of shock tubes so far. However, all the researchers have concentrated on the experimental study of lateral coupling mode.
Choe Yong Chol, a researcher at the Faculty of Mining Engineering, numerically investigated the influence of coupling modes on the explosion shocks and their propagation to shock tubes, and validated it through the test results of the initiation reliability of shock tubes in bunch.
He used lateral and frontal bunch-series coupling modes for the numerical simulations and tests.
The results showed that the peak pressures of explosion shock acting on the inside of shock tubes, and initiation rates were higher for frontal bunch-series coupling mode than for lateral mode, and that the peak pressures acting on the inside of shock tubes by numerical analysis were in good relation with the initiation rate of shock tubes in bunch by tests.
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Jo Nov 3, 2026
Nowadays, rail failure in low temperature environments is a serious problem in many countries across the world. Generally, rails are often damaged due to the large amount of fluctuating stress and impact forces during operation. Rails tend to be damaged in winter when it is cold and the difference between low and high temperatures is great. In addition, the abnormal climate caused by global warming causes a rapid decline in winter temperature and the railroads in extreme regions cannot avoid rail failure at low temperatures, which is a serious problem. According to the research, 60-80% of the rails were damaged in winter from November to March, and 83-121 rails were damged between November and February with relatively low temperature conditions.
In general, different methods of heat treatment and alloying of various elements are widely used to enhance the microstructure and properties of steel. In the past, Ni and V were traditionally used to improve the low temperature properties of steel. Recently, the use of Ti and RE has also been being investigated. Therefore, research has been carried out to apply such alloying or heat treatment methods to rail steels. However, Ni, Ti, RE, etc. are resource-poor and cost-inefficient.
Jon Song Won, a researcher at the Faculty of Material Science and Technology, fabricated rails by adding barium to enhance the low temperature properties of rails and investigated the effect of barium on their microstructure and properties.
He carried out tensile, hardness and impact tests at low temperature to measure and analyze the mechanical properties of the rail steel with Ba addition. The test results showed that the tensile strength of rail steel with 0.03% Ba increased to 1 020MPa, the elongation to 8.0%, and the hardness to HB275 and impact value to 6.8J/cm2 at low temperature.
He investigated the low-temperature toughness mechanisms on the metallic structure of the samples by metal microscopy and scanning electron microscopy. At 0.025wt.% Ba, the average size of pearlite grains in the rail steel was 15μm, and grain refinement was observed in the microstructure. Changes in the size, distribution and shape of inclusions were also observed.
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