Jo Dec 15, 2021
Kim Myong Chol, teacher from Faculty of Heat Engineering succeeded in building and introducing a cogeneration power system, which can provide steam for production of higher pressure and raise the utility rate of energy to the maximum by the mode of combining electricity and heat.
He remodeled the ventilation part of bleeder condensing turbine in order to minimize the loss of effective work arising in steam depressing process for the supply of production steam.
Thus, he provided scientific and technological guarantee of saving natural resources of our country and supplying electricity and steam for production according to consumption process by raising the utility rate of energy in many factories and enterprises.
The pressure of production bleeder steam of the cogeneration system is 1MPa, the temperature of the steam is 270℃ and the amount of supply of steam for production is 0~30t/h.
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Jo Dec 13, 2021
A research group including Kim Ryo Chol, teacher from Faculty of Information Science & Technology fulfilled the big data process, an important part of the smart manufacturing system of an enterprise to build industrial big data aggregation and analysis system in cloud computing environment in which economic technical indices such as norms for the consumption of materials per unit, production time, quality, power consumption etc. can be analyzed in real time.
The group built a platform which can collect and analyze the information of overall process of technical preperation, equipment management and production activity in big data of cloud computing system.
On the basis of it they fulfilled the faulty ratio factor analysis in quality control, big data analysis for the reduction of production period and production optimization analysis based on predictive estimation of quality factor of equipment to provide the assurance of higher economic effectiveness and to contribute to the building of smart manufacturing system.
Thus they not only reduced the management cost, but also improved the quality and productivity of manufactures.
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Jo Dec 10, 2021
A research team including Ri Se Hyong, section leader from Faculty of Automation Engineering succeeded in building the internet of things in an enterprise.
The team built internet of things, the overall system of interconnected physical objects that can make material transportation IT-based and effectively observe and control various kinds of equipment and different processes.
Accordingly, they converted the enterprise into an intelligent factory where production lines are made IT-based and automated, and improved the quality and productivity of products.
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Jo Dec 7, 2021
Kim Kon, researcher from Faculty of Applied Chemical Engineering studied and introduced gas-saving heat radiation fire-grate with our own raw materials, which is useful to reduce food processing time and save gas by promoting combustion and thermal efficiency.
He designed the most appropriate structure of heat radiation fire-grate to apply it to various kinds of gas cooker, and put the synthesizing method, materials and thermodynamic characteristics etc. on a scientific basis.
Flame temperature of heat radiation fire-grate is 70~120℃ higher than those of general cast fire-grates, flame color is orange and thermal efficiency is more than 75%.
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Jo Nov 24, 2021
Although semiconductor capacitive pressure sensor is more sensible and less affected by temperature than resistance pressure sensor and thus more often used in pressure measurement in harsh situations, it has the disadvantage due to the nonlinearity of output characteristic. Therefore, in order to improve this nonlinearity, previous studies proposed various complex forms of electrode structures including double electrode, step electrode, complex electrode. However, these generate several difficult problems in device manufacturing process. Also, many assumptions were needed in mathematical analysis of operation characteristic of device due to the complexity in structure and an exact prediction about the operation characteristic was difficult because the error of analytic model is large.
For the enhancement of overload protection capacity and linearity as well as the sensitivity of device, the structure of capacitive pressure sensor operating in the contact mode is proposed and the structure of electrode is designed in the form of curved surfaces, with which micro-machining is possible, on the basis of MEMS technology, which is developing rapidly throughout the world. In this case, the simple structure leads to simple manufacturing process and lower cost.
The virtual radius model, the analytic model used to analyze contact deformation characteristic in previous studies, correspond to the case in which the electrode is plane and the curved surface electrode and contact deformation characteristic of diaphragm cannot be interpreted with this model.
New mathematical model, which is able to interpret the curved surface electrode and the contact deformation characteristic of diaphragm, was proposed on the basis of previous virtual radius model.
Also, the contact deformation characteristic of diaphragm depending on pressure in concave well substrate touch-mode capacitive pressure sensor is interpreted with the new analytic model and on the basis of it, the response characteristic of sensor was interpreted. The correctness of proposed analytic model and the result of interpretation are tested through simulation using finite element interpreter.
The proposed analytic model is new and esteemed to be useful to design various types of capacitive pressure sensor and to predict and estimate the characteristics of them in the future.
This paper is published by Kang Myong Chol, section leader from Semiconductor Institute on the title of “Capacitance response of concave well substrate touch-mode capacitive pressure sensor: mathematical analysis and simulation” in the SCI magazine, “Microelectronics Journal”.
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Jo Nov 23, 2021
Choe Chol Min, section leader from Faculty of Materials Science and Technology manufactured centrifugal compressor impeller using FDM and investment casting.
Centrifugal compressor impeller, which enables to enhance engine output and combustion efficiency, is very difficult to manufacture as it’s very thin and propene is twisted.
He proposed a new method for manufacturing centrifugal compressor impeller using FDM and investment casting, and a scientific method for raising the extraction rate in casting up to more than 90% by fixing reasonable indices of investment casting process based on the optimal indices of FDM process and simulation analysis.
His paper titled “Manufacture of centrifugal compressor impeller using FDM and investment casting” is published in the SCI magazine, “International Journal of Advanced Manufacturing Technology”.
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