• Korean Journal of Soil Science and Fertilizer
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• v.13 no.3
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• pp.77-83
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• 1981

In order to obtain an imformation on the exchangeable potassium and it's activity ratio to other cations in wet paddy top soil grown by rice, soil samples were taken from bottomless middle size (60cm in dia, and height, respectively) round concrete pot being car ride out with an experiment on the split application of potassium in relation to lime and analysed. The pot experiment was being conducted from 1974 at a farm of the City University of Seoul and the wet soil samples were taken from the paddy in the year of 1976. The samples were extracted with $0.1N-AlCl_3$ solution and analysed regarding the elements. Results obtained are as follows : 1. Less exchangeable potassium was extracted from the soils limed than those unlimed when the same amount of potassium was applied immediatly after flooding. However, when the Potassium was applied two weeks after flooding, the reverse was observed. The fact that the exchangeable potassium is increased in the case that potassium fertilizer applied two weeks after flooding explained as due either to the prohibiting effect of iron or less abserption of potassium by the crop. 2. A remarkable decrease of exchangeable potassium of soils was observed during the vigorous growth stage of rice. 3. The activity ratio of $\frac{K}{(Fe^{{+}{+}}){\frac{1}{2}}}$ was remarkabley low after July 16th at which the soil was considerably reduced. 4. The activity ratio $\frac{K^+}{NH^+}$ of limed soil lasted highly until July 16th. It may be resulted from slow progress of ammonification caused by high pH. 5. A positive correlation was found between $Fe^{{+}{+}}$ and $Ca^{{+}{+}}$ under reduced condition. But there was no correlation between $Fe^{{+}{+}}$ and $K^+$ or $NH^+_4$, because that the concentrations of $K^+$ and $NH^+_4$ in soil fluctuates during growing season.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.204-209
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• 2015

BACKGROUND: Radish (Raphanus sativus L.) is cultivated worldwide and one of important vegetables in Korea where year-round production of radish is possible. Most of radishes in autumn are cultivated with double-row spacing except for Gangwon-do where sing-row spacing is predominant. However, no research has been conducted on double-row spacing in radish cultivation so far. This study was conducted to reveal the optimum double-row spacing in autumn cultivation of radish. METHODS AND RESULTS: Using top two popular autumn radish cultivars 'S' and 'C', seeds were sown in spacing between rows of $55{\times}25$, $45{\times}25$, $35{\times}25$ and $25{\times}25cm$, and that within rows of $35{\times}28$, $35{\times}25$, $35{\times}22$ and $35{\times}19cm$. Plants were harvested 58 days after sowing and leaf weight, length and number, and root weight, length sugar content and pithiness were investigated. In the spacing between rows, no significant difference was observed in leaf weight, length and number in both cultivars; however, 25 cm of spacing between rows significantly reduced the root length and weight in 'S' and 'C' cultivars, respectively. In spacing within rows, 28, 25 and 22 cm did not affect fresh root weight in both cultivars, producing appropriate radish roots of 1,500g on average. However, 19 cm of spacing within rows did not reduced fresh root weight in 'S' cultivar but did significantly in 'C' cultivar (1148.3 g). Sugar contents and pithiness of roots were also affected by spacing but its effect was very small and different between cultivars. CONCLUSION: It is suggested that optimum double-row spacing in autumn radish cultivation is 35 cm and 22 cm of spacing between and within rows, respectively, the spacing that did not reduce the yield and quality of radish roots in two popular autumn radish cultivars.

• Journal of agriculture & life science
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• v.50 no.1
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• pp.211-222
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• 2016

This study was conducted to investigate the physico-chemical meat quality and sensory properties of Holstein steers(n=18, 4 months old, average body weight 160kg) which were divided into 3 groups and fed 2 different energy levels of total mixed rations(TMR)(T1, TDN 74~84%; T2, TDN 77~85%) until 18, 20 or 22 months old, respectively. For loin muscles, 22-month group of T1 and 20- and 22-month groups of T2 had higher fat contents than the other groups (P<0.05). T2 had higher WHC values for 18-month groups among 3 feeding groups (P>0.05). In sensory properties, T1 had higher tenderness, flavor-likeness and overall likeness for 20-month group than the other groups (P<0.05). T2 had higher tenderness, juiciness, flavor likeness and overall likeness in 20- and 22-months groups than 18-month group (P<0.05). For top round muscles, 22-month group had higher fat contents than the other groups of T1 and T2 (P<0.05). T1 had higher in redness(a* value) and yellowness (b* value) of 22-month group (P<0.05). T2 had higher WHC values, lower WBS and CL values in 18-month group than the other groups (P<0.05). In sensory properties, T1 had higher tenderness for 18 and 20-month groups and overall likeness (P<0.05). T2 had higher tenderness in 18-month group. The results of this study showed that longer feeding of agricultural by-product TMR increased the intramuscular fat contents, however, the 18 and 20-months finishing groups were advantageous for the meat quality and sensory properties of Holstein steers.

• The Korean Journal of Archival Studies
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• no.79
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• pp.5-32
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• 2024

The Korean government ranked 3rd among 193 UN member countries in the UN's 2022 e-Government Development Index. Korea, which has consistently been evaluated as a top country, can clearly be said to be a leading country in the world of e-government. The lubricant of e-government is data. Data itself is neither information nor a record, but it is a source of information and records and a resource of knowledge. Since administrative actions through electronic systems have become widespread, the production and technology of data-based records have naturally expanded and evolved. Technology may seem value-neutral, but in fact, technology itself reflects a specific worldview. The digital order of new technologies, armed with hyper-connectivity and super-intelligence, not only has a profound influence on traditional power structures, but also has an a similar influence on existing information and knowledge transmission media. Moreover, new technologies and media, including data-based generative artificial intelligence, are by far the hot topic. It can be seen that the all-round growth and spread of digital technology has led to the augmentation of human capabilities and the outsourcing of thinking. This also involves a variety of problems, ranging from deep fakes and other fake images, auto profiling, AI lies hallucination that creates them as if they were real, and copyright infringement of machine learning data. Moreover, radical connectivity capabilities enable the instantaneous sharing of vast amounts of data and rely on the technological unconscious to generate actions without awareness. Another irony of the digital world and online network, which is based on immaterial distribution and logical existence, is that access and contact can only be made through physical tools. Digital information is a logical object, but digital resources cannot be read or utilized without some type of device to relay it. In that respect, machines in today's technological society have gone beyond the level of simple assistance, and there are points at which it is difficult to say that the entry of machines into human society is a natural change pattern due to advanced technological development. This is because perspectives on machines will change over time. Important is the social and cultural implications of changes in the way records are produced as a result of communication and actions through machines. Even in the archive field, what problems will a data-based archive society face due to technological changes toward a hyper-intelligence and hyper-connected society, and who will prove the continuous activity of records and data and what will be the main drivers of media change? It is time to research whether this will happen. This study began with the need to recognize that archives are not only records that are the result of actions, but also data as strategic assets. Through this, author considered how to expand traditional boundaries and achieves reterritorialization in a data-driven society.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.67-83
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• 1983

The new microsporidia S80 isolated from, Bombyx mori L. in Korea showed ovoid in the morphology of the spores and the size were measured $2.9{\pm}0.28{\mu}$ in length and $1.7{\pm}0.29{\mu}$ width. No other microsporidian spore like this has not been so far isolated from Silkworm. The length of the polar filament extruded in hydrogen peroxide ($H_2O_2$) at $30^{\circ}C$ was $26{\mu}$ of a round cytoplasm on the top. The spores were partly stained with Giemsa, Safranin-O and Gram as the same staining properties as Nosema bombycis, Microsporidia K 79 and other microsporidian spores. The fine structures were observed under scanning eleceron microscope through ultrathin sectioning. The spore wall was composed of three layers ; the thin exospore of an electron dense rippled layer, the thick electron lucent endospore which was thinning considerably at the polar filament insertion point, and the inner limiting membrane. Polar cap present at the sporeapex, with a long polar filament of 12-13 coils, subtending angle of $60^{\circ}$ to spore axis, which is tubular made up of a multilayered and are a benes core, light ring structure enclosing the dance core, the dark ring structure enclosing the inner light ring structure and the other than and light ring structure bounded from cytoplasm. Lamellate polaroplast occupied the anterior part of the spore, and the two neclei with dense nucleoplasm bounded by a double nuclear envelope were cited in the slight downer middle portion of spore. From the characteristics of the shape, size and fine structures, it is certain to reason the Microsporidia S80 belong to the phylum Microspora, class Microspora, order Microsporida, order Microsporida. The shape of two nuclei cited seems to be genus Nosema, but in the classification for the suborder it should be defined wheather pansporoblasts be formed or not and for the genis especial attempts have been made to define the characters which distinguish the disporous genera in the life cycle. Survey through the infection of the bad cocoons during 1980 to 1982 in South Korea the areas contaminated with new microsporidia were revealed 5 provinces of Kyung-Gi, Kang-Won, Chung-Nam and Chun-Nam. Pathological effects inoculated per os at second instar larvae of silkworm, the LD 50 was $7.1{\times}10^7/ml$ as lower pathogenecity than that of Nosema bombycis Naegeli of $1.2{\times}10_7/ml$. While on the other hand the inoculation of the microsporidia at fourth instar larvae lowerd the whole cocoon weight and cocoon shell weight and significant at 1% level. The microsporidia S80 defined it can not be transmitted transovarially from the result of predictive and collective examination of 21 egg batches from the infected female moth.

• Journal of Korean Society of Forest Science
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• v.21 no.1
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• pp.1-34
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• 1974

The author intended to investigate external and internal changes in the cone structure, changes in water content, sugar, fat and protein during the period of seed maturation which bears a proper germinability. The experimental results can be summarized as in the following. 1. Male flowers 1) Pollen-mother cells occur as a mass from late in April to early in May, and form pollen tetrads through meiosis early and middle of May. Pollen with simple nucleus reach maturity late in May. 2) Stamen number of a male flower is almost same as the scale number of cone and is 69-102 stamens. One stamen includes 5800-7300 pollen. 3) The shape is round and elliptical, both of a pollen has air-sac with $80-91{\mu}$ in length, and has cuticlar exine and cellulose intine. 4) Pollen germinate in 68 hours at $25^{\circ}C$ with distilled water of pH 6.0, 2% sugar and 0.8% agar. 2. Female flowers 1) Ovuliferous scales grow rapidly in late April, and differentiation of ovules begins early in May. Embryo-sac-mother cells produce pollen tetrads through meiosis in the middle of May, and flower in late May. 2) The pollinated female flowers show repeated divisions of embryo-sac nucleus, and a great number of free nuclei form a mass for overwintering. Morphogenesis of isolation in the mass structure takes place from the middle of March, and that forms albuminous bodies of aivealus in early May. 3. Formation of pollinators and embryos. 1) Archegonia produce archegonial initial cells in the middle and late April, and pollinators are produced in the late April and late in early May. 2) After pollination, Oespore nuclei are seen to divide in the late May forming a layer of suspensor from the diaphragm in early June and in the middle of June. Thus this happens to show 4 pro-embryos. The organ of embryos begins to differentiate 1 pro-embryo and reachs perfect maturation in late August. 4. The growth of cones 1) In the year of flowering, strobiles grow during the period from the middle of June to the middle of July, and do not grow after the middle of August. Strobiles grow 1.6 times more in length 3.3 times short in diameter and about 22 times more weight than those of female flower in the year of flowering. 2) The cones at the adult stage grow 7 times longer in diameter, 12-15 times shorter diameter than those of strobiles after flowering. 3) Cone has 96-133 scales with the ratio of scale to be 69-80% and the length of cone is 11-13cm. Diameter is 5-8cm with 160-190g weight, and the seed number of it is 90-150 having empty seed ratio of 8-15%. 5. Formation of seed-coats 1) The layers of outer seed-coat become most for the width of $703{\mu}$ in the middle of July. At the adult stage of seed, it becomes $550-580{\mu}$ in size by decreasing moisture content. Then a horny and the cortical tissue of outer coats become differentiated. 2) The outer seed-coat of mature seeds forms epidermal cells of 3-4 layers and the stone cells of 16-21 layers. The interior part of it becomes parenchyma layer of 1 or 2 rows. 3) Inner seed-coat is formed 2 months earlier than the outer seed-coat in the middle of May, having the most width of inner seed-coat $667{\mu}$. At the adult stage it loses to $80-90{\mu}$. 6. Change in moisture content After pollination moisture content becomes gradually increased at the top in the early June and becomes markedly decreased in the middle of August. At the adult stage it shows 43~48% in cone, 23~25% in the outer seed-coat, 32~37% in the inner seed-coat, 23~26% in the inner seed-coat and endosperm and embryo, 21~24% in the embryo and endosperm, 36~40% in the embryos. 7. The content compositions of seed 1) Fat contents become gradually increased after the early May, at the adult stage it occupies 65~85% more fat than walnut and palm. Embryo includes 78.8% fat, and 57.0% fat in endosperm. 2) Sugar content after pollination becomes greatly increased as in the case of reducing sugar, while non-reducing sugar becomes increased in the early June. 3) Crude protein content becomes gradually increased after the early May, and at the adult stage it becomes 48.8%. Endosperm is made up with more protein than embryo. 8. The test of germination The collected optimum period of Pinus koraiensis seeds at an adequate maturity was collected in the early September, and used for the germination test of reduction-method and embryo culture. Seeds were taken at the interval of 7 days from the middle of July to the middle of September for the germination test at germination apparatus.