• Journal of Plant Biology
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• v.15 no.s
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• pp.1-32
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• 1972

In order to utilize for the prevention and preservation of the Han River from the environmental pollution the present studies were carried out to clarify the microflora and estimation of the water pollution levels of the Han River. In addition to the above regional and seasonal fluctuation of the phytoplankton was also examined. Samples of phytoplankton were collected from 6 stations in the South Han River during the period from December, 1971 to October, 1972. The results obtained during the present studies are as follows: 1. The phytoplankton samples collected from 6 stations, Yeoju, Hajapo-ri, Yangpyeong, Daruraegi, Giduwon and Paldang were identified and classified by Engler's classification system(1954). It resulted in 2 phylum, 2 classes, 7 orders, 10 families, 29 genera, 137 species, 1 sub-species, 49 varieties, 6 forma and 2 variety-forma. The total numbers of phytoplankton identified were 195 species, of which 7 families, 27 species, 26 varieties, 4 forma and 2 variety-forma are new to Korea, that of 54 species are first described in Korea. 2. In lower area of the Han River it is found 53 species from Paldang and in middle area it is found 114 species from Giduwon, 95 species from Daruraegi, 66 species from Yangpyeong, 71 species from Hajapori and 81 species from Yeoju. In standpoint of seasonal fluctuation of phytoplankton, the total numbers of the plankton is more abundant in summer than in winter season and it shows bimodal pattern. 3. As compared with previous data which obtained from 30 stations covering estuary to upper area, both South and North Han River, during the period from 1965-1972 it is shown that 10 species of the South Han River and 11 species of the North Han River are found throughout all seasons. Among the above species two are common in both area. In the other hand it is found that 9 species in spring season and 6 species in fall season in the South Han River and 10 species in spring, 23 species in summer, 4 species in fall and 15 species in winter season in the North Han River shows their seasonal fluctuation in this area. Among the seasonal occurrence of phytoplankton 10 species were consider to be indicator for the estimation of biological water pollution levels. 4. According to Fjerdingstad's water pollution level system (1963) the total numbers of 1, 230 species which have been collected from the Han River since 1965 includes 27 species of phytoplankton as indicator; 3 species of blue-green algae, 20 species of diatom, and 4 species of green-algae. 5. With 27 indicator species new estimation of water pollution level system was arranged for water pollution in the Han River. 6. The lower part of the central area of the Han River indicates mesosaprobic. In central area of the Han River shows mesosaprobic and oligosaprobic, but predominant in mesosaporobic. And it is indicated that mesosaprobic, oligosaprobic, and polysaprobic factors mixed up in the North Han River. Compare with their water pollution level in the South and North Han River, with author's new system, it is estimated that North Han River is more polluted than South Han River. 7. The reason why North Han River is more polluted suggested that the selfpurification action was limited by their circulation speed. The rapid speed of water in the North Han River is mainly caused by their topography and water-drainage from waterpower plant. In conclusion the central area of the Han River consist of mesosaprobe zone, as a part with oligosaprobe zone. But the presence of polysaprobe zone in the North Han River gives us many problems in future for the nationa development programme and natural conservation in this area.

• Journal of the Korean association of regional geographers
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• v.2 no.1
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• pp.51-67
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• 1996

There are three main rice-growing regions in the United States: the prairie region along the Mississippi River Valley in eastern Arkansas; the Gulf Coast prairie region in southwestern Louisiana and southeastern Texas; and the Central Valley of California. The Central Valley of California is producing about 23% of the US rice(Fig. 1). In California. most of the crop has been produced in the Colusa, Sutter, Butte, Glenn Counties of the Sacramento Valley since 1912, when rice was commercially grown for the first time in the state(Fig. 2). Roughly speaking, the average annual area sown to rice in California is about 300,000 acres to 400,000 acres during the last forty years(Fig. 3). California rice is grown under a Mediterranean climate characterized by warm, dry, clear days, and a long growing season favorable to high photosynthetic rates and high rice yields. The average rice yield per acre is probably higher in California than in any other rice-growing regions of the world(Fig. 4). A dependable supply of irrigation water must be available for a successful rice culture. Most of the irrigation water for California rice comes from the winter rain and snow-fed reservoir of the Sierra Nevada mountain ranges. Less than 10 percent of rice irrigation water is pumped from wells in areas where surface water is not sufficient. It is also essential to have good surface drainage if maximum yields are to be produced. Rice production in California is highly mechanized, requiring only about four hours of labor per acre. Mechanization of rice culture in California includes laser-leveler technology, large tractors, self-propelled combines for harvesting, and aircraft for seeding, pest control, and some fertilization. The principal varieties grown in California are medium-grain japonica types with origins from the cooler rice climates of the northern latitudes (Table 1). Long-grain varieties grown in the American South are not well adapted to California's cooler environment. Nearly all the rice grown recently in California are improved into semidwarf varieties. Choice of variety depends on environment, planting date, quality desired, marketing, and harvesting scheduling. The Rice Experiment Station at Biggs is owned, financed, and administered by the rice industry. The station was established in 1912, as a direct result of the foresight and effort of Charles Edward Chambliss of the United States Department of Agriculture. Now, The station's major effort is the development of improved rice varieties for California.

• Tuberculosis and Respiratory Diseases
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• v.67 no.4
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• pp.318-324
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• 2009

Background: A diagnosis and treatment of chest wall tuberculosis (CWTB) is both difficult and controversial. The aim of this study was to collect information on the optimal treatment for CWTB. Methods: The clinical features, radiographic findings, and treatment outcomes of 26 patients, who underwent surgery and were diagnosed histopathologically, were retrospectively analyzed. Results: The most common presenting symptom was a palpable mass found in 24 patients (92.3%). In all patients, CT revealed a soft tissue mass that was accompanied by a central low density, with or without peripheral rim enhancement. The sensitivity and specificity of the bone scintigram for bone involvement were 87.5% and 100%, respectively. CWTB was diagnosed preoperatively by aspiration cytology and smear for acid-fast bacilli in five out of 11 patients. Twenty-three patients (88.5%) underwent a radical excision and three underwent incision/drainage or an incisional biopsy. The duration of antituberculous medication was 7.5${\pm}$3.98 months with a follow-up period of 28.2${\pm}$26.74 months. Among the 20 patients who completed their treatment, nine received chemotherapy for six months or less and 11 received chemotherapy for nine months or more. Two patients had a recurrence four and seven months after starting their medication. Conclusion: A 6 month regimen may be appropriate for CWTB patients who have undergone a complete excision.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.6
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• pp.419-424
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• 2008

Objective of this study was to evaluate the adaptation and the soil conservation effect of improved wild vine in sloped upland of highland about 600m from sea level in Korea. A mainly producing district of the improved wild vine in Korea was distributed 230m to 540m from sea level, and its rainfall ranged 1,200 to 1,700 mm. The lowest temperature was from -19.6 to $-25.4^{\circ}C$. Their soil texture was from sandy loam to clay loam, where drainage class was well drained and the contents of soil organic matter and total nitrogen in the improved wild vine's cultivation area were higher than those of Chinese cabbage's cultivation area in the highland. According to improved wild vine's cultivation methods, the amounts of soil erosion were 25.5,4.1, and $1.8MT\;ha^{-1}$ in clean culture, part sod + mulching, and nature sod, respectively. Those were below 30 to $80MT\;ha^{-1}$ of sloped upland at highland in Korea. The result suggests that it is possible to cultivate the improved wild vine over wintering at 600m of highland above the sea level. We can substitute the improved wild vine for Chinese cabbage in the highland for soil conservation.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.308-308
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• 2017

The low and unstable yield of soybean has been a major problem in Japan. Excess soil moisture conditions are one of the major factors to restrict soybean productivity. More than 80 % of soybean crops are cultivated in converted paddy fields which often have poor drainage. In central and eastern regions of Japan, the early vegetative growth of soybean tends to be restricted by the flooding damage because the early growth period is overlapped with the rainy season. Field observation shows that induced excess water stress in early vegetative stage reduces dry matter production by decreasing intercepted radiation by leaf and radiation use efficiency (RUE) (Bajgain et al., 2015). Therefore, it is necessary to evaluate the responses of soybean growth for excess water conditions to assess these effects on soybean productions. In this study, we aim to modify the soybean crop model (Sinclair et al., 2003) by adding the components of the restriction of leaf area development and RUE for adaptable to excess water conditions. This model was consist of five components, phenological model, leaf area development model, dry matter production model, plant nitrogen model and soil water balance model. The model structures and parameters were estimated from the data obtained from the field experiment in Tsukuba. The excess water effects on the leaf area development were modeled with consideration of decrease of blanch emergence and individual leaf expansion as a function of temperature and ground water level from pot experiments. The nitrogen fixation and nitrogen absorption from soil were assumed to be inhibited by excess water stress and the RUE was assumed to be decreasing according to the decline of leaf nitrogen concentration. The results of the modified model were better agreement with the field observations of the induced excess water stress in paddy field. By coupling the crop model and the ground water level model, it may be possible to assess the impact of excess water conditions for soybean production quantitatively.

• Journal of Chest Surgery
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• v.40 no.8
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• pp.569-573
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• 2007

A 3 month old female baby, who had been diagnosed with right atrial isomerism associated with total anomalous pulmonary venous return (TAPVR), a functional single ventricle and major aortopulmonary collateral arteries (MAPCA), underwent left MAPCA unifocalization and left Blalock-Taussig shunt (3.5 mm) at 3 months of age. The post-operative course was complicated by pulmonary venous congestion, and the drainage site of the TAPVR was found to be stenotic on echocardiography. We performed sutureless repair of the TAPVR along with unifocalization of the right MAPCA. She was put on an extracorporeal membrane oxygenator for 8 days after the 2nd operation, and she was able to come off the oxygenator with the placement of a central shunt (3 mm). She developed tracheal stenosis, which was presumably due to longstanding endotracheal intubation, and she then underwent tracheostomy. She was discharged to home on day 104 after the 1st operation, and she has been followed up for 2 months in a good clinical condition.

• Economic and Environmental Geology
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• v.17 no.3
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• pp.215-230
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• 1984

Petrological, paleomagnetic, geomorphological and structural studies on the southern part of, so called, Chugaryeong rift valley, have been carried out in order to clarify the nature of the rift valley. Three stages of volcanic activities characterized by Jijangbong acidic volcanic rocks and tholeiitic and andesitic basalt of Cretaceous age(?), and Jongok Quaternary olivine basalt occurred along the Dongducheon fault line. Jijangbong acidic volcanic rocks distributed in the central part of the studied area consist of rhyodacite, acidic tuff and tuff breccia, which are bounded by Dongsong fault on the east and Daegwangri fault on the west. The Jongok basalt differs from those of Ulrung and Jeju islands in mineralogy, chemical composition and differentiation. Jongok basalt distributed along the Hantan river dilineates the vesicles curved toward downstream direction and increment of numbers and thickness of lava flow toward upstream direction. These facts suggest that lava flowed from upstream side of the river. Rectangular drainage patterns also support the presence of the Dongducheon, Pocheon, Wangsukcheon and Kyonggang faults which were previously known. LANDSAT image, however, does not show any lineaments which could be counted as a graben or rift valley. Displacement of Precambrian quartzite and Jurassic Daedong supergroup along the southwestern extension of the Dongducheon fault shows the right lateral movement. The Paleomagnetic study of the tholeiitic and andesitic basalts from Baegeuri, Jangtanri and Tonghyeonri located at 2. 3km east, 0km east, and 1.5km west of Dongducheon fault respectively shows that their VGP(Virtual Geomagnetic Pole) being to intermediate geomagnetic field of short duration which suggests that they formed in almost same period. Mean VGP of Jongok basalt is located 82.4N and 80.6E. This is in good coincidence with worldwide VGP of Plio-Pleistocene indicating that Jongok basalt was extruded during Plio-Pleistocene epoch, and suggesting that the studied area has been tectonically stable since then. From the present study, the tectonic episode of the region is concluded as following three stages. 1. The 1st period is worked by the Daebo orogeny of Jurassic during which granodiorite was intruded in Precambrian basement. 2. The 2nd period is the time when right lateral strike-slip fault of NNE-SSW direction was formed probably during late Cretaceous to Paleogene and the Jijangbong acidic volcanic rocks and the older basalts were extruded. 3. The 3rd period is the time when the fault was rejuvenated during Pliocene or Pleistocene accompanied by the eruption of Jongok basalt. As a conclusion, geologic structure of the studied area is rather fault line valley than graben or rift valley, which is formed by differential erosion along the Dongducheon fault suggesting a continuation of the Sikhote-Alin fault. The volcanic rocks including the Jijangbong acidic rocks, tholeiitic-andesitic basalt and olivine basalt are associated with this fault line.

• Journal of the Korean association of regional geographers
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• v.5 no.2
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• pp.119-132
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• 1999

The Korean Peninsula, jutting southward from the Asian mainland into the Pacific Ocean, is surrounded by numerous bays and islands on three sides. The study area of this research is the coastal area surrounding the Sacheon Bay, which is located in the mid-southern tip of the peninsula. Historically, the bay region took the role of the main gate leading to the western part of Kyung-nam Do(Province) due to the fact that the bay is the nearest coast to Chinju, the central city of the province. The Sacheon Bay had provided important sea routes from the old days until the early twentieth century. Because of the bay's sea routes, the bay region has been militarily of great significance. Recently, road/rail/highway/airplane transportation functions have become gradually increased but sea transportation function has been decreased in the region. As the Sacheon Bay was rich in fishery resources, dozens of fishing villages in the bay region depended on fishery and marine product industries for long years. But the inflow of the fresh water used to cause serious damage to the fishing industry in the bay region after a drainage canal from the Nam River was constructed in 1969. As a result, the industry has dwindled gradually for last decades. Recently, a couple of industrial parks were constructed along the coast and many manufacturing factories were built on the parks. It has been expected that many jobs lost in fishery and agriculture are replaced by new opportunities in industry. More than half of the workers employed in the parks' factories commute from the city of Chinju. It is asserted in this paper that the transportation, fishery, manufacturing, and tourism functions of the Sacheon Bay region are closely associated with. The characteristics of the region can be well understood through the functional changes and associations.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.15-24
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• 2004

The Seokgatap pagoda composed of mainly alkali granite and other minor pink-feldspar granite, fine-grained granite, granodiorite, diorite, gabbro, and tuff. Despite the small loss and damage derived from joints, its peel-off and exfoliation are serious enough to cause the heavy deterioration on the stone surface. The chemical and petrological weathering has partly replaced the original rock-forming minerals with clay minerals and iron oxyhydroxides. Based on the petrogenesis, rock materials of the pagoda is very similar to rocks of Dabotap pagoda and the Namsan granite in the Gyeongju. The central fart of the pagoda has sunken highly, which caused all the corners to split and the structural transformation to become worse. The reverse V-shaped gaps between the materials have broken stones filled in a coarse way. The iron plates inserted between the upper flat stone laid on other stones and tile pagoda body in the north and east side has been exposed in the air and corroded, discoloring of the adjacent stones. The overall diagnosis of the Seokgatap pagoda is the deteriorated functions of the stone materials, which calls for a long-term monitoring and plans to reinforce the stone surfaces. But the main body including the pagoda roof stone needs washing on a regular basis, and the many different cracks should be fixed with glue by using the fillers or hardeners designed for stone cultural properties after removing the cement mortar. In case of the replacement of the stone materials with new stones, it's necessary to examine the pagoda for the center of gravity and support intensity of the materials. The structural stability of the pagoda can be attained by taking a reinforce measure in geotechnical engineering and making a drainage. The ground humidity, which has aggravated weathering and structural instability, should be resolved by setting up a humidity reduction facility. The contamination of lichens and bryophyte around the pagoda and on the surface is serious. Thus biochemical treatments should be given too in order to prevent further biological damages and remove the vegetation growing on the discontinuous planes.

• Journal of Chest Surgery
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• v.3 no.2
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• pp.73-90
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• 1970

Clinical perfusion data on 16 cases of cardiopulmonary bypass using Sigmamotor pump and RyggKyvsgaard Oxygenator which performed at Seoul National University Hospital during the period of Aug. 1968 to Aug. 1970 was analized. AIl cases were hemodiluted and the perfusion was carried out under the normothermic condition. The age of the patients ranged between 6 and 43 years. The b:dy weight varied between 18.3 and 54.0 kg and the body surface area between 0.78 and 1. 59$M^2$. The priming solution was consiste:I with fresh ACD blood. Hartmann solution and Mannitol. The average amount of priming was approximately 2242 ml. The average hemodilution rate was 17%. The flow rate ranged from 1.7L to 3.5L/Min/$M^2$ and averaged 2.4L/Min/$M^2$ or 78mI/Min/kg. The duration of perfusion varied from 22 to 110 min with average of 56.9 minutes. Some hemodynamic responses were observed. The arterial pressure dropped immediately after the initiation of partial perfusion and was more marked after the total perfusion foIlowed by gradual increase to the safety level. The central venous pressure reflected the reduced blood volume especially in the cases of prolonged perfusion which lasted over 60 min. In most of the cases, red blood cell count decreased and white blood ceIl count increased after the perfusion. Hemoglobin level was decreased, averaging of 12.5mg%, Hct 3.3% and platelets count of 18% postoperatively. Plasma hemoglobin increased mildly, from pre-perfusion average value of 4. 06mg% to postperfusion value of 22.5mg%. Serum potassium was 4.4mEq/L pre-operatively and was decreased to 3.7mEq/L postoperatively. Five cases showed definite hypopotassemia immediately after the operation. Sodium and chloride decreased mildly. These electrolyte changes are thought to be related with hemodilution. diuretics and reduced blood volume during and after the perfusion. Arterial blood pH value revealed minimal to moderate elevation from preperfusion average value of 7.376 to 7.461 during perfusion and then 7.365 after perfusion. The pC02 and hicarbonate showed minimal to moderately lowered values. The total CO2 was decreased. Buffer base decreased during perfusion (Av. 42.6mEq/L) and further decreased after the perfusion (Av. 40.8mEq/L). These arterial blood acid base changes suggested that the metabolic acidosis was accompanied by respiratory alkalosis during and immediately after the perfusion. Authors belived that the acidosis could more effectively be corrected with the more additional dose of bicarbonate than we used by this study. The chest tune drainage during the first 24 hours following operation was 1158 ml in average. One case (Case No. 15) showd definite bleeding tendency and it was believed that the cause might be due to the defect of heparin and protamine titration. The average urinary out put during 24 hours post-perfusion was 1291ml. One case (Case No. ]) showed definite post perfusion oliguria. As conclusion hemodilution using fresh ACD blood. Hartmann and Mannitol solution added with Bivon and high flow rate unler normothermia. was thought to amelioratc the severity of mctabolic acidosis during and after perfusion with relatively satisfactory effect on the diuresis and bleeding tendency.