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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Jo Dec 20, 2022
Kim Jang Hak, a section head at the Faculty of Distance Education, has proposed a new learning content model and a communication interface with interactivity and feedback structure considering the requirements and levels of learners while meeting the pedagogical requirements for distance education.
Generally, distance education system consists of three components, namely, learner, learning content and learning management system.
Learning-based interaction is mainly of three types, i.e. learner-content, content-management system and learner-management system.
Learning content consists of a content object and an interaction object with communication interface. The content object is Sharable Content Object (SCO) for teaching activities like lecture, experiment, practice, etc. The interface object is for interaction with learners through the communication interface and standardized communication with the management system.
If the structure of content is properly defined and standardized for interaction and feedback control, the reusability, extension and inter-operability of content can be ensured and it can be used in other management systems. The design of the content in hierarchical structure allows reuse of some of the content object in other contents.
On the basis of SCORM, the content model and learning object metadata are defined in the figure above. In the figure, “organization” is a learning unit and “item” is learning resources. “Resource” is a reference set, that is, SCO or asset of minimum unit. The root folder of the content has index.html, imsmanifest.xml, XSD and DTD, metadata.xml and resources. The content model is in imsmanifest.xml and metadata files.
Finally, he managed to form the content by adding communication interface with four control objects for interactivity and feedback control to the content model in hierarchical structure. The communication interface is made up of display control object, learning control object, communication control object and evaluation control object.
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Jo Dec 18, 2022
There is a man who has amused and pleased everyone for hundreds of years only with his sleeping posture. It is a figure in the picture “Draught Ox Driver” by painter Kim Tu Ryang (1696-1763) during the feudal Joson dynasty.
The picture gives a lifelike portrayal of a draught ox driver who has fallen into a deep sleep under the shadow after all day’s tiring work. In the middle of the picture is painted a big ox and on the right is an ox driver fast asleep on the grass, which gives a glimpse into the country life in our country at that time. The ox driver in the nap in the shadow of the summer is portrayed in a simple and plain way. The thick untrimmed hair, firmly closed lips, dangling earlobes, raised corners of the eyes, undone front of the jacket and untied cord of the trousers are so impressive. The ox chewing the grass in the middle shows the gentleness and strength of Korean oxen and the neatness of the owner who values and takes good care of it. The surroundings like the bottom of the willow, the drooping branches and the grass feel as if they were emitting the fragrance of soil.
Well-composed and soft with thin coloring, the painting is an excellent masterpiece in the aspect of portrayal of that time. On the one hand, it looks as if you can hear cicadas and other insects buzzing and the farmer snoring, and the ox driver, on the other hand, looks so fast asleep that nobody would be willing to awaken him.
In a word, the painting “Draught Ox Driver” by Kim Tu Ryang exhibited in the Korean Art Gallery is a masterpiece that has stimulated extraordinary interest of a lot of people for hundreds of years only with a sleeping figure.
Jo Hwi Nam, section head at the Academy of Social Sciences
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