Jo Oct 4, 2022
Many countries and nations in the world have wrestling, one of strength events. However, hardly any of them are comparable with Korean wrestling, which has such a long history and tradition, a strong national character and a unique form and way of playing, and is imbued with rich and optimistic national sentiments.
Korean wrestling is one of the national sports events, in which two people try to take opponents down by strength and skills holding opponents’ thigh bands or waist bands. The term ssirum (Korean wrestling) came from an archaic word “hilhuda”, which meant making every effort not to be defeated. The sound “hilhum”, the noun form of “hilhuda”, changed little by little into silhum → silum → sirum → ssirum.
Created through the labour of our hard-working people to conquer the nature, ssirum became a typical event of our national sport in ancient times and entered the track of its development. Mural paintings in Koguryo tombs including Ssirum Tomb in the period of the Three Kingdoms (late 4th century) and Jangchon Tomb No.1 (mid-5th century) give a lifelike portrayal of scenes of ssirum which was very popular in those days. In the period of Koryo, too, ssirum was widely done as a popular sporting event. It was so popular that even one of the kings of the Koryo dynasty used to do ssirum with the officials at Court, far from looking after the affairs of the state. “Ssirum” painted by Kim Hong Do, a famous artist in the 18th century, shows that Korean wrestling is a popular national sport that is simple in preparation but diverse in the ways of playing, and that it can be played anywhere anytime.
Korean wrestling has three main features: diversity in the techniques by thigh bands, giving strong stamina, fighting spirit and herculean strength, and a popularized event that can be played without any restrictions on a place, time and players.
Thanks to the warm love of Chairman
Today, under the warm care of the respected Comrade
Im Sung Bin, section head at the Academy of Social Sciences
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Jo Oct 3, 2022
“Embedded Computer Technique” is a subject that covers the principle and method of building a control system around an embedded processor using the structure and function of the processor.
In the past, all students were given the same preparation tasks and they had them checked orally. Therefore, they paid little attention to preparation and some of them made no preparations for lectures.
That is why Choe Hak Gun, a researcher at the Faculty of Communications, focused his attention on attracting his students to doing preparation tasks.
It is true that “Embedded Computer Technique” at first attracted every student’s interest as an embedded computer system has positive applications in reality, but the lectures on making and running embedded computer systems tended to make many students discouraged since the lectures are mainly focused on theories.
In order to overcome such shortcomings, he selected a simulation tool method and gave preparation tasks for which students had to use the simulation tool. With the simulation tool, the students can design circuits, write and run a program and evaluate the accuracy anytime as they want.
First, he presented preparation tasks so that they could grasp the point of the coming lecture from them. As they have already learnt about PROTEUS, simulation tool which is widely used for an embedded system, it is quite possible for them to do so.
Second, he properly evaluated how well they did their preparation tasks.
Due to the time limit, it is impossible to check everybody’s work, so he asked the students to hand in their tasks in the form of e-documents in advance. He chose the best ones among them to point out the good sides and bad sides of their tasks. It helped raise their self-confidence. In addition, he gave them chances to have a full understanding of the main point of the lecture by providing time to explain on their own.
As a result, the trend of memorizing faded out and instead many of them tried to design a circuit and write and run a program all by themselves. Some of them came up with several creative design methods and programming methods while doing their preparation tasks by the simulation tool. It resulted in the improvement in the thinking ability of the students.
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Jo Oct 1, 2022
Codechef August Long Challenge went on from August 12 to 15, 2022.
Over 23 000 contestants from tens of countries and regions including our country, China and India took part. 170 contestants competed in Division 1.
A total of 30 contestants including 10 KUT students won the first place in Division 1.
Codechef September Long Challenge went on from Sep. 9 to 12. More than 20 000 contestants from tens of countries and regions took part. Division 1 drew 140 contestants.
A total of 28 contestants including 8 KUT students took the first place in Division 1.
KUT studenst are making constant effort to hold fast to its position in the contest, which will always lead to brilliant fruition.
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Jo Sep 29, 2022
Cadmium sulfide (CdS) is an important II–VI compound semiconductor material with applications in several heterojunction photovoltaic systems including CdTe and CIGS solar cells. There are several physical and chemical deposition techniques used for deposition of CdS thin films including RF sputtering , evaporation, close space sublimation (CSS), closed space vapor transport (CSVT), metal organic chemical vapor deposition (MOCVD), chemical bath deposition (CBD), spray pyrolysis, successive ionic layer adsorption and reaction (SILAR), etc.
Among these, CBD is one of the simple stand inexpensive large-area deposition techniques. CBD is most widely used since it is not only available at low temperatures and easy to control but also it helps produce uniform, compact and adherent films.
Kim Hyon Chol, a researcher at the Faculty of Electronics, has investigated the influence of deposition parameters such as reactant concentration, bath temperature and deposition time on the CdS thin film properties when a CdS thin film, a window layer of a CdTe solar cell, was deposited by the chemical bath deposition (CBD) method without stirring.
Influence of solution concentration: When the reactant concentration is too high, the reaction rate becomes fast and the color of solution turns yellow, resulting in films with brittle nature and poor uniformity due to the adherence of a great amount of CdS precipitates onto the surface, which is undesirable for solar cell fabrication. On the other hand, low concentration leads to a decrease in deposition rate and non-uniformity of thin films. When the reactant concentration is controlled suitably, the residual solution after the reaction can be colorless to obtain uniform, compact and transparent films.
Influence of bath temperature: The bath temperature affects the surface morphology, microstructure and adhesion of CdS thin films. At lower temperatures, an abundance of CdS particles are directly deposited because of lower solubility products of CdS (Ksp). Meanwhile, higher bath temperature yields thin films of poor quality due to the increase in Ksp and the decrease in the precipitation rate. The increase in the bath temperature decreases the grain size and promotes the formation of CdS thin films.
Influence of deposition time: Deposition time influences the thickness of films with constant reactant concentration. At the initial stage of the formation of a thin film, a large number of voids made by CdS colloid particles form discontinuous films. For CdS thin films with these voids, the performance of solar cell is strongly affected by the decrease in shunt resistance. As the deposition time increases, the surface of a film becomes compact, uniform and continuous.
The measurements of transmittance were carried out for all deposition parameters. The performances of solar cells with different S/Cd ratios, the variation of the crystal phase with NH4Cl concentration and the surface morphology with the bath temperature were studied. Finally, he determined the optimum deposition parameters through the systematic analysis.
You can find more information in his paper “Effect of the reactant concentration, bath temperature and deposition time on the properties of CdS thin film prepared by the chemical bath deposition method” presented to the SCI Journal “optical materials”.
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Jo Sep 27, 2022
A research group led by Choe Kwang Hyok, an institute head at the Faculty of Shipbuilding and Ocean Engineering, has developed a wave power device for providing power of a navigation and marking buoy.
The device is a floating WAB (wave activated body) and it consists of a point absorber, power take-off (PTO) of a wave energy converter, an electric generator, etc.
The point absorber consists of a floating body, a spar and a heave plate.
The floating body is heaved on wave surfaces and the spar is a relatively fixed body by a mooring system. The heave plate is strongly connected with the spar and it can effectively improve the heave response of the device by providing additional damping and added mass.
When the wave power device is on the water surface, the floating buoy and spar oscillate up and down vertically due to the wave. At that time, the link attached to the floating buoy moves up and down by relative amplitude differences occurring in the amplitude and phase of two buoys and the alternating motion of the link changes into rotary motion through the specially designed chain driving device.
The rotary motion of the chain driving device increases up to the rated rotary velocity of the generator and it is transmitted to the generator through the multiplying gear (1:3) and the belt (1:3), which generates power of up to 100w at the wave height 0.2~1m.
The diameters of the floating buoy, the spar and the heave plate are 1.2m, 0.3m, 1m respectively and the whole mass is 980kg.
The wave power device can be utilized to supply power not only to navigation and marking buoys, but also to other measuring and monitoring devices on the sea.
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Jo Sep 25, 2022
A research team led by Kim Pyong Hun, a section head at the General Assay Office, has developed an electrolytes analyzer whereby a rapid analysis of the concentration of ionic electrolytes in human serum is made by using selective ionic electrodes.
The electrolytes analyzer is a medical analytical instrument used to diagnose several diseases by rapidly determining the concentrations of ionic electrolytes such as potassium, sodium, chloride and calcium and pH in serum or urine.
It consists of power supply unit, sample injection unit, detection unit, waste disposal unit, etc.
The power supply unit supplies power to the signal amplifier and the controller. The sample injection unit has a sample injection needle which injects samples, and a switching valve which selects necessary liquor such as calibration solutions, elution solutions, activation solutions for electrodes, etc. The detection unit has six electrodes, that is, a potassium ionic selective electrode, a sodium ionic selective electrode, a chloride ionic selective electrode, a calcium ionic selective electrode, a pH electrode and a reference electrode. The waste disposal unit has a peristaltic pump for drainage and a box for wastes.
The application range of the electrolytes analyzer is 0.5~15.0mmol/L for potassium, 30.0~200.0 mmol/L for sodium, 20.0~200.0 mmol/L for chloride, 0.10~6.00 mmol/L for calcium and pH 4.00~9.00.
The CV of the electrolytes analyzer is ≤1.5% for potassium, sodium and chloride and ≤2.0% for calcium and pH.
The operation conditions are 220V, 170 W, 5~35℃ temperature and ≤65% humidity.
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