• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.21 no.1
• /
• pp.97-124
• /
• 1976

To find out the most effective method of treatments for the induction of sprouting of dormant seed potato pieces for the fall crop production of Irish cobbler, this experiment was carried out with sprout inducing bed and field performance trial. In GA treatments, about 10 days were required to sprout and resulted uniform and thin 3-4 sprouts per tuber piece, but sprouts were slender and rooting was not observed. In Ethrel treatments, 20-25 days were required, and sprouts were inferior than that of GA treatment in uniformity of sprouting, and percentage of rotten pieces and of healthy sprouted tuber pieces, but number of sprouts per tuber pieces was low, being 1-2, and sprouts were short, thick, and healthy, and showed good rooting. In GA and Ethrel mixture treatments, 1-2 more days were required to sprout than GA treatments, but sprouts were relatively healthy, and other sprouting pattern were like that of GA treatments. In Ethylene chlorohydrin and 6-Benzyl-adenine treatments, sprouting was like that of Ethrel treatments, but much more days were required than Ethrel treatments and tendency of severe rotting was observed. Optimum treating methods of promising chemicals found to be 1-2 and 2-5 ppm GA solution, 500 and 1000-2000 ppm Ethrel solution, and 1-2＋250-500 and 5＋250-500 ppm GA and Ethrel mixture solution for 60 min. treatment of tuber piece and whole-tuber, respectively. Induction of sprouting in dry and hot time resulted severer rotting of tuber pieces during the induction of sprouting and with the advancement of dormancy, being delayed in date of treatment, tendency of promotion of sprouting and rooting was observed. When sprouted tuber piece was transplanted at the same date, yields were in order of Ethrel, GA and Ethrel mixture, and GA treatment, indicating the correlation between yield and healthiness of sprout and rooting status of sprouted tuber piece. In all treatments, earlier transplanting resulted higher yields.

• Korean Journal of Environmental Biology
• /
• v.40 no.4
• /
• pp.455-463
• /
• 2022

To understand functional changes of forest ecosystems due to climate change, correlation between decomposition rate of leaf litter, an important function of forest ecosystems, and microclimatic factors was analyzed. After 48 months elapsed, percent remaining weight of Quercus mongolica leaf litter was 27.1% in the east aspect and 37.0% in the west aspects. Decay constant of Q. mongolica leaf litter was 0.33 in the east aspect and 0.25 in the west aspect after 48 months elapsed. Initial C/N ratio of Q. mongolica leaf litter was 38.5. After 48 months elapsed, C/N ratio of decomposing Q. mongolica leaf litter decreased to 13.43 in the east aspect and 16.72 in the west aspect. Average air temperature and soil temperature during the investigation period of the research site were 8.2±9.0 and 9.1±9.3 in the east and 8.5±7.4 and 9.3±7.3℃ in the west aspect, respectively, with the west aspect showing higher air and soil temperatures. Soil moisture showed no significant difference between east and west aspects (average soil moisture: 19.4±11.0% vs. 20.5±5.7%). However, as a result of analyzing the correlation between decomposition rate and microclimatic factors, it was found that the decomposition rate and soil moisture has a positive correlation(r=0.426) in the east aspect but not in the west aspect. Our study shows that the correlation between decomposition rate and microclimatic factors can be significantly different depending on the direction of the aspect.

• Korean Journal of Environment and Ecology
• /
• v.37 no.6
• /
• pp.429-438
• /
• 2023

The forest in the lower Tumen River serves as an important ecosystem spanning the territories of North Korea, Russia, and China, and it provides habitat and movement corridors for diverse mammals, including the endangered Amur tiger (Panthera tigris) and Amur leopard (Panthera pardus). This study focuses on the Mijiang area, situated as a potential ecological corridor connecting North Korea and China in the lower Tumen River, playing a crucial role in conserving and restoring the biodiversity of the Korean Peninsula. This study aimed to identify mammal species and estimate their relative abundance, occupancy, and distribution based on the 48 camera traps installed in the Mijiang area from May 2019 to May 2021. The results confirmed the presence of 18 mammal species in the Mijiang area, including large carnivores like tigers and leopards. Among the dominant mammals, four species of ungulates showed high occupancy and detection rates, particularly the Roe deer (Capreolus pygargus) and Wild boar (Sus scrofa). The roe deer was distributed across all areas with a predicted high occupancy rate of 0.97, influenced by altitude, urban residential areas, and patch density. Wild boars showed a predicted occupancy rate of 0.73 and were distributed throughout the entire area, with factors such as wetland ratio, grazing intensity, and spatial heterogeneity in aspects of the landscape influencing their occupancy and detection rates. Sika deer (Cervus nippon) exhibited a predicted occupancy rate of 0.48, confined to specific areas, influenced by slope, habitat fragmentation diversity affecting detection rates, and the ratio of open forests impacting occupancy. Water deer (Hydropotes inermis) displayed a very low occupancy rate of 0.06 along the Tumen River Basin, with higher occupancy in lower altitude areas and increased detection in locations with high spatial heterogeneity in aspects. This study confirmed that the Mijiang area serves as a habitat supporting diverse mammals in the lower Tumen River while also playing a crucial role in facilitating animal movement and habitat connectivity. Additionally, the occupancy prediction model developed in this study is expected to contribute to predicting mammal distribution within the disrupted Tumen River basin due to human interference and identifying and protecting potential ecological corridors in this transboundary region.

• Journal of agricultural medicine and community health
• /
• v.26 no.1
• /
• pp.37-56
• /
• 2001

This study was conducted to analyze the degree of changes in knowledge and attitude toward smoking and to examine the factors affecting knowledge and attitude for smoking after providing a smoking prevention program based on social influence model for a year to middle school students. Study population consists of 665 subjects of middle school students(aged 14 years) in Gumi city in Kyeongsangbukdo Province. Among them three-hundred sixty-seven students(intervention group) were educated to a smoking prevention program for 1 year from April 1999 to April 2000. School-based four-class program to prevent smoking was developed. The program provides instruction about short and long-term negative physiologic and social consequences of smoking and also discussed the health hazards of smoking, social pressure to smoke, peer norms regarding tobacco use, and refusal skill. A 45-item self-administered structured questionnaire was designed to evaluate the change of knowledge, attitude, smoking rate and the amount of smoking. The instrument was comprised of 11 knowledge items, thirteen attitude item and demographic items. Each scales were created by summing responses to each items within each scales and high scores on the knowledge, attitude, and smoking behavioral intention scales indicated positive responses. Based on the changes before and after the implementation of smoking prevention program between intervention and control group, the change of scores on knowledge were significantly different between the control group and the intervention group(p<0.05) and the change of scores on the attitude toward smoking was significantly different between intervention and control group. The change of smoking rate were not showing a significant difference between two groups but the amount of smoking were significantly reduced in intervention group than control group. In multiple regression analysis on changes of knowledge about smoking, the variables of smoking prevention program education, previous knowledge on smoking and students' school performance were selected the significant variables. In multiple regression to analysis of the factors influencing changes in attitude toward smoking, the variables of smoking prevention program education, previous knowledge on smoking were shown to be significant. The smoking prevention program was effective on change of knowledge and attitude of middle school students. In considering that the policy should be needed to extent of implementation of school-based health education curricula based on social influence model and it would contribute to reduce smoking of students.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.36 no.5
• /
• pp.407-428
• /
• 1991

The eastern coastal area having variability of climate is located within Taebaek mountain range and the east coast of Korea. It is therefore ease to cause the wind damages in paddy field during rice growing season. The wind damages to rice plant in this area were mainly caused by the Fohn wind (dry and hot wind) blowing over the Taebaek mountain range and the cold humid wind from the coast. The dry wind cause such as the white head, broken leaves, cut-leaves, dried leaves, shattering of grain, glume discolouration and lodging, On the other hand the cold humid wind derived from Ootsuku air mass in summer cause such symptom as the poor rice growth, degeneration of rachis brenches and poor ripening. To minimize the wind damages and utilize as a preparatory data for wind injury of rice in future, several experiments such as the selection of wind resistant variety to wind damage, determination of optimum transplanting date, improvement of fertilizer application methods, improvement of soils and effect of wind break net were carried out for 8 years from 1982 to 1989 in the eastern coastal area. The results obtained are summarized as follows. 1. According to available statisical data from Korean meteorological services (1954-1989) it is apperent that cold humid winds frequently cause damage to rice fields from August 10th to September 10th, it is therefore advisable to plan rice cultivation in such a way that the heading date should not be later than August 10th. 2. During the rice production season, two winds cause severe damage to the rice fields in eastern coastal area of Korea. One is the Fohn winds blowing over the Taebaek mountain range and the other is the cold humid wind form the coast. The frequency of occurrence of each wind was 25%. 3. To avoid damage caused by typhoon winds three different varieties of rice were planted at various areas. 4. In the eastern coastal area of Korea, the optimum ripening temperature for rice was about 22.2$^{\circ}C$ and the optimum heading date wad August 10th. The optimum transplanting time for the earily maturity variety was June 10th., medium maturity variety was May 20th and that of late maturity was May 10th by means of growing days degree (GDD) from transplanting date to heading date. 5.38% of this coastal area is sandy loamy soil while 28% is high humus soil. These soil types are very poor for rice cultivation. In this coastal area, the water table is high, the drainage is poor and the water temperature is low. The low water temperature makes it difficult for urea to dissolve, as a result rice growth was delayed, and the rice plant became sterile. But over application of urea resulted in blast disease in rice plants. It is therefore advise that Ammonium sulphate is used in this area instead of urea. 6. The low temperature of the soil inhibits activities of microorganism for phosphorus utilization so the rice plant could not easily absorb the phosphorus in the soil. Therefore phosphorus should be applied in splits from transplanting to panicle initiation rather than based application. 7. Wind damage was severe in the sandy loamy soil as compared to clay soils. With the application of silicate. compost and soil from mointain area. the sand loamy soil was improved for rice grain colour and ripening. 8. The use of wind break nets created a mocro-climate such as increased air. soil and water temperature as well as the reduction of wind velocity by 30%. This hastened rice growth, reduced white head and glume discolouration. improved rice quality and increased yield. 9. Two meter high wind break net was used around the rice experimental fields and the top of it. The material was polyethylene sheets. The optimum spacing was 0.5Cm x 0.5Cm. and that of setting up the wind break net was before panicle initiation. With this set up, the field was avoided off th cold humid wind and the Fohn. The yield in the treatment was 20% higher than the control. 10. After typhoon, paddy field was irrigated deeply and water was sprayed to reduce white head, glume discolouration, so rice yield was increased because of increasing ripening ratio and 1, 000 grain weight.

• Korean Journal of Environmental Agriculture
• /
• v.14 no.2
• /
• pp.221-231
• /
• 1995

The objectives of the present study were to find out the differences in growth and weed competition of rice under the foggy and non-foggy condition, and finally, the fundamental data for the establishment of the paddy weed control system under the locational foggy regions. The research was carried out on tin trays ($0.12m^2$) in greenhouse equipped with an Auto Foggy System(SAE KI RTN Co.). The results are summarized as follows: Exp. I. Difference in rice growth under the foggy and non-foggy condition. 1. While the plant height was not affected, the number of tillers was decreased by the foggy condition. The ratio of the number of effective tiller, however, became higher under the foggy condition. 2. Due to the fog present, the heading rate was decreased and heading time was delayed. 3. The foggy condition did not affect the dry weight of rice straw whether they were grown under the foggy or non-foggy condition. However, yield components such as the number of ears, the number of grains per ear, thousand kernel weight and percentage of ripeness were reduced. Particularly, weights of perfect brown and unpolished rice were also decreased. Exp. II. Effect of the duration of competition between weed and rice grown under the foggy condition on the growth of rice plant. 1. There was no difference in the height of rice grown under a different duration of competition. There was a clear tendency that the number of tillers of rice grown under the foggy condition was decreased as the duration of competition was decreased. 2. When the duration of competition was longer than 60 days, the heading rate was decreased and the initiation of heading was also delayed by 2-4 days. 3. Under the foggy condition, the duration of competition for more than 40 days affected dry weight of rice straw and the difference in yield was greatest in the non-competition and competition for more than 40 days.

• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.33B no.11
• /
• pp.140-149
• /
• 1996

Cursive characters are written on an economical principle to reduce the motion of a pen in the limit of distinction between characters. That is, the pen is not lifted up to move for writing a next stroke, the pen is not moved at all, or connected two strokes chance their shapes to a similar and simple shape which is easy to be written. For these reasons, strokes and korean alphabets are not only easy to be changed, but also difficult to be splitted. In this paper, we propose a curvature stroke modeling method for splitting and matching by using a structural primitive. A curvature stroke is defined as a substroke which does not change its curvanture. Input strokes handwritten in a cursive style are splitted into a sequence of curvature strokes by segmenting the points which change the direction of rotation, which occur a sudden change of direction, and which occur an excessive rotation Each reference of korean alphabets is handwritten in a printed style and is saved as a sequence of curvature strikes which is generated by splitting process. And merging process is used to generate various sequences of curvature strikes for matching. Here, it is also considered that imaginary strokes can be written or omitted. By using a curvature stroke as a unit of recognition, redundant splitting points in input characters are effectively reduced and exact matching is possible by generating a reference curvature stroke, which consists of the parts of adjacent two korean alphasbets, even when the connecting points between korean alphabets are not splitted. The results showed 83.6% as recognition rate of the first candidate and 0.99sec./character (CPU clock:66MHz) as processing time.

• The Journal of Engineering Geology
• /
• v.7 no.3
• /
• pp.191-205
• /
• 1997

Measurements on subsurface movement of the Songsanri tomb site including the Muryong royal tomb was conducted using a tiltmeter system for the period of 15 months form July 7, 1996 to September 30, 1997. Two coordinate tilt monitoring data shows the biggest movement rate of 2.3mm/m/yr toward south in the frontal wall(N-S tilt) of the Muryong royal tomb. Southward tilting of bricks above the southern fire place in the western wall of the Muryong royal tomb is a proof of southward tilting of the royal tomb since its excavation in 1971. The eastern wall of the Muryong royal tomb is also tilting toward inside the tomb with the rate of 1.523mm/m/yr. Furthermore, tilting rate of wall increases twice in rainy season. It is interpreted tbat infiltration of water into the tomb and nearby ground in rainy season results in dangerous status for the safety of tomb structure. On the whole, normal component tilting of the walls of the 5th tomb is large than its shear component. It shows a small displacement toward one direction without no abrupt change in its direction and amount of tilting. The tilting rate of walls of the 6th tomb is about 8.8mm/m/yr in the dry season which is much bigger than those of other tombs in rainy season. Deformation events of walls of the tombs are closely related to amount of precipitation and variation of temperature. In comparison with different weather conditions, tilting is much bigger during the period of rainy weather than sunny weather. It is interpreted that rainwater flew into the turm through faults and nearby ground. High water content in nearby ground resulted strength of ground. The tilting event of walls shows a hysterisis phenomenon in analysis of temperature effect on tilting event. The walls tilt rapidly with steep rising of temperature, but the tilted walls do not come back to original position with temperature falling. Therefore, a factor of steep increase of the temperature must be removed. It means the tomb have to be kept with constant temperature. The observation of groundwater level using three boreholes located in construction site and original ground represented that groundwater level in construction site is higher than that of original ground during the rainy season from the end of June to August. It means that the drainage system of the Muryong royal tomb is worse than original ground, and it is interpreted that the poor drainage system is related to safety of tomb structure. As above mentioned, it is interpreted that artificial changes of the tomb environment since the excavation, infiltration of rainwater and groundwater into the tomb site and poor drainage system had resulted in dangerous situation for the tomb structure. According to the result of the long period observation for the tomb site, it is interpreted that protection of the tomb site from high water content should be carried out at first, and the rise of temperature by means of the dehumidifier inside the tomb must be removed.

• Journal of Animal Science and Technology
• /
• v.46 no.3
• /
• pp.347-354
• /
• 2004

Four Holstein cows were used in a 4 ${\times}$ 4 Latin square experiment to study effects of fat sources on rumen metabolism and digestibility of nutrients. All cows were fed a total mixed diets containing 60% silage and 40% concentrate. The four concentrates were formulated to contain either Megalac(MEG), formaldehyde-treated whole linseed(LIN), a mixture (50 : 50, oil basis) of fish oil and formaldehyde-treated whole linseed(MIX), or no fat source in the concentrate but 500g per day of linseed oil being infused into the duodemm (OIL). The rumen pH was lowest in OIL among the treatments(P < 0.05), but ammonia N concentration in the rumen was not significantly different among the treatments. The differences of total VFA, acetate, propionate, iso-butyrate and iso-valerate concentrations were not significant among the treatments. While, butyrate and valerate were highest in OIL and lowest in MEG(P < 0.05 and P <0.01, respectively). In addition, A:P ratio was also highest in OIL and lowest in MEG(P < 0.05). As expected, intake of nutrients(DM, OM, NDF and ADF) was lowest in OIL among the treatments(P < 0.01). However, all nutrients flow to the duodenum, and digestion in the rumen and total tract were not significantly different among the treatments. Intake of N was highest in MEG, but lowest in OIL treatment(P < 0.01). Duodenal flow of total N, nonammonia N and microbial N was not significantly different across the treatments. In addition, microbial synthesis and ammonia N and total N digestibility were not affected by different dietary fat sources. The present results show that fermentative characteristic and microbial efficiency in the rumen, and nutrients digestibility in the rumen and total tract were not depressed by supplementation of as much as 6% dietary fat sources.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.33 no.2
• /
• pp.109-117
• /
• 1997

In order to hold the behavior of fish school to the set-net, a series of tag-recapture experiments were carried out in two fishing grounds of the middle sized set-nets which were located in 20m depth on the coast of Keojedo and Namhaedo in the Southern part of Korea from September to October in 1996. In the experiments, the leading ability of the leader and the fish court and the recapturing ability of the bag nets were checked out for the six species of fish in method of discharging the tagged fishes at side points of leader, and the middle points of the fish court and the bag nets in a hauling step, and recapturing them at the bag nets in the next hauling. The results obtained are as follows; 1. The ratio recaptured at the both side bag-nets in the next hauling after discharged from the fish court in the previous step was 20.3% in small size of mackerel Scomber japonicus, 16.2% in small size of horse mackerel Trachurus japonicus, 10.3% in black sea-bream Acanthopagrus schlegelii, 19.1% in red barracuda Syhyraena pinguis, 16.3% in halfbeak Hemiramphus sajori, 20.0% in gizzard shad Konosirus punctatus individually, and totally in six species of fish, that was 17.2%. 2. The ratio recaptured at the same bag net after discharged in the both side bag-nets was 21.7% in small size of mackerel, 21.5% in small size of horse mackerel, 6.7% in black sea-bream, 17.8% in red barracuda, 16.8 in half-beak, 19.1% in gizzard shad individually, and totally in six species of fish, that was 18.8%. 3. The leading ratio from side points of the leader departed from door in 25m to fish court was 58.9% in small size of mackerel, 74.6% in small size of horse mackerel, 38.0% in black sea-bream, 54.7% in red barracuda, 58.6% in half-beak, 54.5% in gizzard shad individually, and totally in six species of fish, that was 57.8%. So it was assumed that the leader of set-net was very effective in leading to the swimming direction of small size of mackerel, small size of horse mackerel, red barracuda, half-beak and gizzard shad. 4. Red barracuda, half-beak and gizzard shad entered into bag net of upstream in large numbers than bag net of downstream, and small size of horse mackerel and black sea-bream entered into bag net of downstream in large numbers than bag net of upstream. 5. Small size of mackerel and small size of horse mackerel had high remaining rate in the bag net of downstream, and black sea-bream, red barracuda and half-beak had high remaining rate in the bag net of upstream.