Jo Dec 27, 2022
Every country has their symbolic animals that reflect the history and culture, excellent dispositions and extraordinary abilities of their people. Among them is a dog.
Phungsan Dog is a native breed of Korea that has left an indelible mark in the history of our nation for thousands of years. It has been tamed for ages by our ancestors in severe natural environments of the northern uplands where there were a large number of beasts such as a tiger, a bear, a wild boar, a wolf, etc.
Well adapted to the topography and climate of the mountainous forest areas in our country, the dog has features of a typical hunting dog. It is famous for its cleverness, persistence, bravery and swiftness. Though this dog is of smooth nature and quite obedient to its keeper at ordinary times, it shows a strong fighting spirit and bravery at the time of hunting and it never gives a fight up. Full of vitality, it is resistant to the cold and diseases.
It was registered as a state natural monument in April, Juche 45 (1956) thanks to the state measure taken by President
When visiting Ryanggang Province in May, Juche 47(1958), the President said that Phungsan Dog thoroughbred is a very good breed, underscoring the need to survey its thoroughbred.
Chairman
On November 7, Juche 103(2014), the respected Comrade
Today, Phungsan Dog is widely known as a national dog that symbolizes the spirit of properous Juche Korea and as a world’s famous dog.
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Jo Dec 25, 2022
Time-dependent deformations of rock are important factors for the design and construction of tunnels in the rock masses with time-dependent strength and deformation properties. Therefore, determination of the displacement and the stable time of tunnels is an indispensable task in geotechnical engineering, especially the design and construction of underground structures.
However, in some types of rock masses, tunnel displacement may increase for months or years after excavation owing to the rheological behavior of the surrounding rock masses, which greatly influences the selection of an initial tunnel support system, excavation layout, and determination of its load-carrying capacity.
Therefore, Han Un Chol, a researcher at the Science Engineering Institute, has made it possible to predict the final displacement of rock mass surrounding a tunnel, which is gradually stabilized in the shape of an S-type saturated curve by using the improved nonequidistant grey Verhulst model (INGVM) with Fourier series.
The traditional non-equidistance grey model (NGM(1,1)) and non-equidistance grey Verhulst model (NGVM) were compared to examine the feasibility of INGVM application. He only used the monitored displacements during excavation to predict the final displacement and stable time of the tunnel excabated in time-dependent rock mass.
The results showed that the proposed model was highly accurate and adaptable.
The details of this are carried in his paper “Prediction of Final Displacement of Tunnels in Time-Dependent Rock Mass Based on the Nonequidistant Grey Verhulst Model” published in the SCI Journal “Mathematical Problems in Engineering”.
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Jo Dec 24, 2022
The Korean people, who have loved cleanliness from ancient times, invented methods of making and altering national clothes suited to their physiques and hobbies in the course of creative labor. Constantly developing them, they have been proud of being dressed in neat clothes.
While washing their clothes, our people discovered effective washing methods to wash dirt away in consideration of the material for clothes. Laundry usually went through primary washing, main washing and boiling before being rinsed and dried. In the primary washing, the first step in the washing, laundry is dipped in warm water for a light rub. It was mainly for heavily soiled laundry such as the inside of quilts. In the main washing, detergents are applied to the primarily washed ones before rubbing, clubbing or stamping. Due attention should be paid to the washing of silk fabric or velvet that are widely used for Korean clothes.
When ironing velvet, it should be held up from the floor, with its naps facing downwards.
Korean clothes should be carefully stored according to the seasons. Neatly folded clothes should be placed layer upon layer in a drawer: those for the present season on the top, those for the next season under them and those for the last season on the bottom. Those for a long time of storage need special care. For example, Korean jackets are placed with their right and left skirts aligned before the breast-ties are brought together, and then they are folded on the shorter breast-tie. The sleeves are folded on the armpit line. The skirt trimly folded in five to six folds is folded in half length. It is a good idea to hang skirts on a hanger.
It is important to be well aware of the methods of washing and keeping Korean clothes and to get dressed culturally.
Kang Hyon Sim, researcher at the Academy of Social Sciences
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Jo Dec 23, 2022
Ozone is one of the strongest oxidizers and disinfectants, and it does not leave any residual toxin as it is decomposed into oxygen. That is why it has been widely used in domestic and industrial areas such as disinfection of drinking water and air, wastewater treatment, pulp bleaching, food processing, decolorization and deodorization.
A research team led by Kim Jong Guk, a researcher at the Nano Physics Engineering Institute, has developed enamel ozone tubes and different types of DBD ozone generators. The most effective and practical one of all ozone generation methods is dielectic barrier discharge (DBD), which generates non-thermal equilibrium plasma.
A DBD ozone generator consists of an ozone tube and high-frequency high-voltage power supply. The ozone tube has an enameled steel tube as an internal electrode and a stainless steel tube as an external electrode. It shows stronger resistance to thermal shock and better heat dissipation than glass or ceramic material.
Addition of nano-powders as mill additive increases adhesive strength, dielectric constant and dielectric strength, which ensures a long lifespan of the generator and produces high efficiency of ozone generation. Water cooling for internal and external electrodes effectively prevents temperature rise when the ozone tube discharges, thus ensuring safe operation and high ozone concentration output. By using high-frequency power supply and intelligent control system, ozone output can be changed on demand.
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Jo Dec 22, 2022
Apatite is an important mineral resource that plays an important role in many fields such as production of phosphoric acid and phosphate fertilizer.
Flotation technology is the most important method for beneficiation of apatite, and anionic fatty acid and their salt collectors are most-commonly used collectors in the direct flotation of phosphate ores.
Anionic fatty acid collectors have been proven both theoretically and in plant practice to be highly efficient in the flotation of apatite. Under basic conditions (pH10), fatty acid is saponified, which results in a negatively charged carboxylate ion. The negatively charged carboxylate ion then reacts with calcium on the apatite surface to form calcium carboxylate. This chemisorption method is generally considered to be the primary method of fatty acid adsorption onto the apatite surface in alkaline conditions.
Although a flotation mechanism of apatite using sodium oleate as a collector has been studied by several investigators, the flotation mechanism, reaction processes and associated surface reaction products still remain controversial.
Jong Kwang Sok, a researcher at the Faculty of Mining Engineering, synthesized a new collector for apatite flotation by a series of reactions including sulfation and amidation, using sodium oleate as raw material. Then, he carried out an investigation on the flotation behavior and mechanism of oleic acid amide onto apatite by micro flotation tests, zeta potential measurements, and XPS analysis.
The flotation results showed that mixing sodium oleate and oleic acid amide could float apatite well in a pH range of 7.5–9.5 even at the acid number of 120 mgKOH/g and it exhibited better collecting capacity on apatite than a sodium oleate collector. The XPS analysis data correlated with zeta potential showed that the zeta potential of apatite became more negatively charged at around pH8.5 and the oleic ions (C17H33COO−, (C17H33COO)22− and C17H33CONH−) in the mixing collector suspension could get chemisorbed by Ca-O bond formation on the apatite surface, and that the molecular (C17H33CONH2) and micelles ((C17H33CONH2)m) in oleic acid amide could get chemisorbed on the apatite surface by Ca-O or Ca-N bond formation.
You can find more information about this in his paper “Flotation mechanism of oleic acid amide on apatite” published in the SCI Journal “Colloids and Surfaces A: Physicochemical and Engineering Aspects”.
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Jo Dec 21, 2022
The peasant dance created and developed by our people over a long period of time is a Korean folk art where people sing and dance merrily drumming several kinds of percussion instruments like a drum, a gong, a small gong, janggu and a small drum and skillfully turning round decorative tassels. Loved and enjoyed most by our people, it fully reflects the national feelings and sentiments by dint of peculiar depictive elements such as Korean dance moves, Korean tune, Korean folk songs and national instruments, national costumes and decorative tassels, all of which are full of national flavor.
The peasant dance is the oldest of all forms of folk art created by our people. Its birth and development are based on the farm work of our ancestors in early primitive years. Being passed down along with the long national history, it has given our people a hope of life and romance and developed into a folk art reflecting the peculiar emotion of the Korean nation. There are several arrangements of the peasant dance, but it is largely divided into three ― a road dance where a peasant music and dancing group advances in procession to attract people to the dancing venue; a concert dance where several kinds of dancing, instrumental music performance and folk songs are harmoniously combined; a private dance where individual dancers demonstrate their dancing techniques one after another. Unlike other forms of folk art, the peasant dance has a unique feature, i.e. turning of 12-fathom decorative tassels, which adds a lot more excitement to the atmosphere of the dancing venue. Such dancing props as decorative tassels are seen only in the peasant dance of our country.
The peasant dance is a popular folk dance that has always existed in the lives of our people. In popular folk games and on holidays, it boosted merry atmosphere and when they were working, it encouraged their spirit for raising the work efficiency. In the anti-aggression, anti-feudal struggles, it was the cause of horror for enemies but the source of confidence for our people.
The peasant dance still plays an important part in carrying forward the unique traditions of our national art. Today, it resounds even louder all over the cooperative fields of our country and it is giving a full rein to the vitality as a popular form of mass art.
Kim Son Yong, researcher at the Academy of Social Sciences
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