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Brilliant LeaderShip

With Heart of Mother

With the holiday of February approaching, Chairman Kim Jong Il happened to learn that the officials were racking their brains over his birthday spread, and flatly declined it. A few days later when ...

Going Only with Roast Potatoes

Once Chairman Kim Jong Il was on the field guidance to Taehongdan County. Time passed a lot, so the Chairman happened to have lunch there. When he pulled up at a vacant lot ...

Cherished View of Arms

One day in June 1995, Chairman Kim Jong Il said meaningful words about arms, sitting together with some commanding officers of the Korean People’s Army. He said: I value and love a pistol most. ...

Most Precise Prescription

One day in December 2016, the respected Comrade Kim Jong Un visited December 6 Children’s Camp of Kangwon Province, which was magnificently built on the scenic seashore. Noting that they produced finishing materials ...

Historic Event

It was when the liberated country was inundated with joy over the historic proclamation of the Law on Sex Equality. One day President Kim Il Sung heard from some women officials that the ...

Benevolence

One day in September 1961, President Kim Il Sung paid a visit to Pyongyang Hotel (then) to meet the delegates to the historical 4th Congress of the Workers’ Party of Korea and ...

News

Jo Dec 12, 2025

Lithium and its compounds have been widely used in several fields including battery, aerospace and light metal alloys due to their special properties. Recently, gradual exhaustion of lithium resources on land makes it important to extract lithium from seawater and salt lake brine which are rich in lithium.

There are several methods for recovering lithium from lithium resources including precipitation, solvent extraction and adsorption. Among them, adsorption method is suitable for recovering lithium from seawater and salt lake brine due to its simple process and high recovery.

Inorganic adsorbents are widely applied in the adsorption method. Among them, ion sieve materials are most widely used. At present, there are two types of lithium ion sieves―manganese type and titanium type. The ion sieve of manganese type has a disadvantage of big dissolution rate of manganese. Therefore, research on the titanium type with higher chemical stability is becoming more intensive.

Ri Song Ho, a section head at the Institute of Analysis, has prepared a titanium-type lithium ion sieve for recovering lithium from seawater and salt lake brine, and investigated its characteristics.

First, he prepared the precursor of lithium ion sieve (Li2TiO3) by the solid state reaction with lithium carbonate (Li2CO3) and titanium dioxide (TiO2) as raw materials. Then, he prepared a lithium ion sieve (H2TiO3) by extracting lithium from the precursor with HCl solution.

The extraction rate of lithium and the dissolution loss rate of titanium are 91.23% and 0.2%, respectively, during HCl treatment of the precursor. The equilibrium adsorption capacity of lithium on the prepared ion sieve is 38.8mg/g.

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Jo Dec 11, 2025

Saenap (a Korean brass wind instrument) is a peculiar national wind instrument.

Hard woods like paktal tree, date tree, etc. were used for its hollow pipe.

It is basically the same as a flute in the way of playing. It is characterized by bright and gorgeous timbre, fluency and strong appeal, and it produces great volume.

It is used as a melodic instrument in holiday amusements, instrumental music of peasants and dance music boasting of the pleasure of rich harvest, and in mixed orchestra it usually appears in the parts stimulating the national interest.

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Jo Dec 9, 2025

Currently, research on parameter tuning methods is active due to the widespread use of PID controllers in industrial practice. Many studies have been carried out on self-tuning methods to tune the parameters of PID controllers with varying plant parameters, bringing about remarkable successes.

Meanwhile, the Particle Swarm Optimization (PSO) algorithm is a kind of optimization method based on the theory of cluster intelligence, which has been widely applied in the field of function optimization, neural network learning, multiobjective optimization, fuzzy control system, etc. The population optimization algorithm is easily applicable to various types of problems because there are no complex crossover and mutation operations like in genetic algorithms. The greatest advantage of PSO algorithm is its fast convergence speed, simplicity of evolution operation, low computational cost and small number of parameters used in it.

The T-S fuzzy model approximates nonlinear characteristics, and inference using it can be used as a tool to implement controllers or fuzzy models with optimal and adaptive functions because it is simple and convenient for mathematical analysis and it can be easily combined with PID control or adaptive control.

Kim Yong Su, a researcher at the Faculty of Automatics, has proposed a method for designing a PID controller, based on the characteristics of PSO algorithm and T-S fuzzy model.

According to the proposed method, you first use the PSO algorithm to determine the position of a dominant pole which minimizes the judge function consisting of Integral of Absolute Error (IAE) and overshoot value and then express it as a T-S fuzzy model to determine the parameters of a PID controller using fuzzy inference.

The proposed method allows you to get both the optimal dominant pole and the exchanging frequency at the same time, and to get a good control result as the overshoot value is small.

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“Aggregated Blood Cells Separating Lamina” cleaning the blood

The scientists and researchers of Kim Chaek University of Technology developed a simple medical instrument using “Aggregated blood cells separating lamina” which radiates far infrared rays capable good health by cleaning the human blood.

Nov 15, 2024