• 한국작물학회지
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• 제46권1호
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• pp.47-52
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• 2001

In order to develop more stable seedling stand method in wet direct rice seeding culture, the effect of making the drainage ditches was studied in both methods of broadcast seeding on floody paddy surface and puddled-soil drill seeding. In a broadcast seeding on floody paddy surface, the ditching after seeding using a tractor or small ditch maker improved the seedling stand, and reduced the floating seedling and herbicide injury by accelerating the drainage. Suitable ditching time was at 2 days after seeding (DAS) for the tractor and at 3 DAS for the ditch maker. In the puddled-soil drill rice seeding culture, the ditching before seeding with a ditch maker at 3 days after draining effectively improved the seedling stand due to quick draining through well formed the seeding furrows. In the puddled-soil drill seeding, seedling stand number showed higher in both ditching plots synchronized with seeding compared with both only draining treatment at 1 DAS without ditching and the flooding plot condition for 6 DAS. And the suitable ditching depth was 6 cm, as considered the ditching status and drained status. These results suggest that the ditching in wet direct rice seeding is an resonable practice for improving the seedling stand through the accelerating drainage of field.

• 대한토목학회논문집
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• 제14권5호
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• pp.1167-1175
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• 1994

본 연구는 도시 배수구역에서 지표면유출과 우수로의 홍수추적 과정을 통하여 홍수량을 산정하는데 있어서, 지표면유출 해석방법이 결과치에 미치는 영향을 분석하였다. 지표면유출 해석이론의 비교연구를 위해서는 RUNOFF, ILLUDAS, SBUH, RRL 등의 해석모형들을 사용하였으며, 배수관망내 흐름 해석에는 EXTRAN을 사용하였다. 가상 및 실측 강우, 유출량자료가 있는 유역에 대하여 각각 유출해석을 실시하였다. 각 도시 소배수구역의 유출모형에 의한 결과는 도시홍수량 산정에 상당한 영향을 미치고 있음을 보여주고 있다. 지표면유출 해석 결과치에 가장 큰 영향을 미치는 인자는 도달시간으로 판단되었다. 적용 모형 중 RUN-EX(RUNOFF-EXTRAN) 법이 포장, 비포장유역의 해석에 모두 적합하였으며, 다른 모형들에 비해 실측치에 가장 근사하였다.

• 생태와환경
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• 제40권4호
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• pp.560-568
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• 2007

The objectives of this study were to analyze ecological effects on effluents from the Sagok Stream (Chonnam province) as an abandoned mine drainage through necropsy-based health assessments and fish exposure tests, and to conduct In situ field pilot tests for restoration of stream water. Also, we analyzed water quality including general parameters and heavy metals. The tests were performed three times on April 2005, April 2006, and April 2007. Also, we constructed a reactor facility in the outflowing point of the abandoned mine for the remediation of AMD wastewater. In lab test, death rates in all three treatments were ${\geq}50%$ in the experiments. Necropsybased fish tissue assessments using the Health Assessment Index (HAI), indicated that the most frequently damaged tissue was liver (average: 20.8). Values of Health Assessment Index were lower in the control than any other treatments of T1, T2, and T3 and three treatments showed a distinct toxicity impacts by the AMD. In situ lethal test, concentration of Fe, Al and Zn decreased particularly by 85%, 99% and 94%, respectively through the disposal facility. Values of pH, ranged from 3.1 to 7.0, increased by 2.3 fold (mean=5.1) along with the reduction of metal contents. All fishes in P1 cage died 100% on 3 days later after the experimental setting, while all fishes in the P6 died 100% on 9 days later. Overall, these results evidently provide a key methodology for pilot test using the disposal facility and also clarify the toxicity of AMD once again, so this approach used in the pilot facilities here may reduce the acidic and toxic effects in the abandoned mining drainage.

• 한국작물학회지
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• 제62권2호
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• pp.134-142
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• 2017

Crop production in rice paddy fields is of great importance because of declining rice consumption and the low self-sufficiency ratio for field crops in Korea. A controlled drainage system (CDS) is recognized as an effective means to adjust water table (WT) levels as needed and control soil water content to improve the soil environment for optimum crop growth. The present study evaluated the effects of a CDS on soil characteristics, including soil water distribution and soybean development in paddy fields. The CDS was installed with two drain spacing (3 m and 6 m) at the experimental paddy field at the National Institute of Crop Science, Miryang, Korea. It was managed with two WT levels (0.3 m and 0.6 m) during the growing season. Soil water content, electrical conductivity and plant available nitrogen content in the soil were significantly greater in the 0.3 m WT management plots than in the 0.6 m plot and the control. At the vegetative stage, chlorophyll content was significantly lower with higher WT control because of excess soil moisture, but it recovered after the flowering stage. Soybean yield increased with WT management and the 0.6 m WT treatment produced the greatest grain yield, $3.38ton\;ha^{-1}$, which was 50% greater than that of the control. The CDS directly influenced outflow through the drains, which significantly delayed nutrient loss. The results of this study indicated that WT management by CDS can influence soil characteristics and it is an important practice for high yielding soybean production in paddy fields, which should be considered the crop growth stages for stable crop production.

• 한국관개배수논문집
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• 제3권2호
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• pp.57-67
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• 1996

The purpose of this environmental study is to predict the environmental consequences of human development activity and to plan appropriate measures to eliminate or reduce adverse effects and to augment positive effects. The need to avoid adverse impacts a

• 한국토양비료학회지
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• 제49권3호
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• pp.287-292
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• 2016

The objectives of this study were to investigate the effects of soil neutralizing treatments on soil characteristics and growth of Aster koraiensis in the acid soil of abandoned metal mine for selection of proper neutralizer. The most effective neutralizers were acid mine drainage sludge, waste lime + oyster and compost. Those neutralizing treatments showed promoting growth of Aster koraiensis. According to this study, it is applicable of acid mine drainage sludge, waste lime + oyster and compost to neutralize acid soil for rehabilitation in abandoned metal mine. However, follow-up study is necessary to calculate proper ratio of each neutralizer.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.363-366
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• 2005

Social survey and auditory experiment on residential noises such as floor impact, air-bome, bathroom, drainage and traffic noises were conducted to investigate the effects of sensitivity and background noise levels on subjective response to residential noises. Results of survey showed that multiple questions for sensitivity to noise have a more power for discrimination against subjective response to noise than single question. It was also found that the correlation between sensitivity and annoyance was relatively low, but the differences in annoyance between sensitivity groups were significant. Result of auditory experiment showed that effects of sensitivity on annoyance were different according to noise type and noise level. It was also shown that the difference in annoyance between the lowest sensitive stoup and the highest sensitive group was significant in low noise level. The effects of background noise on subjective responses to noise was also different according to noise source and noise level, and were significant in low noise level of airborne and drainage noise.

• 대한통합의학회지
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• 제9권4호
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• pp.19-28
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• 2021

Purpose : The purpose of this study was to apply manual lymphatic drainage (MLD) and high-frequency diathermy (HFD) to patients with axillary web syndrome (AWS), one of the side effects of breast cancer surgery, and to treat upper extremity pain, volume, function of the upper extremity, (joint range of motion; ROM, disabilities of the arm, shoulder and hand; DASH) and quality of life before and after treatment. It is to determine the effect of treatment by checking the level change. Methods : This study is a case series. A total of 5 patients diagnosed with AWS after breast cancer surgery voluntarily participated in this study. The intervention program consisted of stretching, MLD and HFD. It was conducted 3 times a week for 30 minutes for 4 weeks. In order to compare the effects of pain (numeric pain rating scale; NPRS), volume, upper limb function (ROM, DASH) and quality of life (the European organization for research and treatment of cancer quality of life questionnaire-breast, EORTC QLQ-BR23) evaluations were compared before and after 4 weeks of intervention. All measured variables were analyzed and expressed as mean, standard deviation and percentage. Results : The shoulder NPRS level of the subjects in all case groups decreased, the volume decreased and the shoulder flexion, abduction ROM increased. It showed improvement in DASH and quality of life, QLQ-BR23. Conclusion : After breast cancer surgery, we confirmed the possibility that MLD and HFD treatments could be effective in improving pain, decreasing volume, increasing upper extremity function, and quality of life for patients who have difficulties with AWS. The possibility has been confirmed, and additional research is needed by increasing the number of participants in the experiment in the future.

• 한국조경학회지
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• 제33권5호통권112호
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• pp.69-82
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• 2005

These studies were carried out (1) to investigate the growth characteristics of Sedum album L. in the field, (2) to propose a suitable shallow peen roof system for this plant, and (3) to evaluate plant growth in the proposed system over the long term. The growth characteristics, such as morphological properties, growth habit, shade tolerance, and flowering, were surveyed. In experimental shallow green-roof systems, the effects of drainage type, substrate type, and soil depth on plant growth were investigated. Then drought tolerance was investigated. After planting Sedum album L. in the proposed system survival rate, cover, and resistance to insects, heal and cold were evaluated for about 2 years. The results of these studies are summarized below. 1. In the field, the aboveground part of Sedum album L. did not die back during the winter. Plant height was 4$\sim$7 cm. Roots were distributed to a depth of 5$\sim$7 cm. Sedum album L. is a compact ground-cover plant that spreads vigorously. Shading condition of less than $30\%$ of full sunlight didn't cause any trouble, but shading conditions above $87\%$ made the shape of the shoots and leaves abnormal. The plant bloomed from June to August and had a rather large compound umbel of white, star-shaped flowers. 2. Two systems, a drainage-blend-10 cm soil depth and a reservoir$\cdot$drainage-blend-15 cm soil depth, performed best in terms of cover, fresh weight, and dry weight. The first has an advantage for green roofs because it is lighter than the latter. 3. In drainage-blend-10 m soil depth and modified reservoir · drainage-blend-10 cm soil depth system no plants died for about 4 months after stopping the irrigation. The visual quality of the latter system was above 5 for 4 months and that of the former was under 5 after 2 months. In the field, however, the drought tolerance of Sedum album L. grown in the former would be enough to withstand the dry season. Considering the urban ecosystem and the importance of healthy growth the modified reservoir $\cdot$ drainage-blend-10 cm soil depth system was finally recommended. This system was composed of a 4 cm thick drainage layer and drain outlets placed at a height of 2.5 cm. 4. In the proposed system, the survival rate was $100\%$, and there was no injury induced by insects and heat. The leaf density decreased a little in winter. Cover increased throughout the year. Sedum album L. was planted with a cover of 72$cm^{2}$ on 3 April 2003; on 16 June 2003 and 15 June 2004, cover was $132.66\pm$5.87 $cm^{2}$(1.8 times) and $886.98\pm$63.51 $cm^{2}$(12.3 times), respectively.

• 농업과학연구
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• 제10권2호
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• pp.371-381
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• 1983

This study is aimed at identifying the economic effects of drainage improvement projects. The total area of poor drainage is equivalent to 170,000ha, 13% of the total area of paddy field in Korea. The development of poor drained paddy is an urgent problem considering the low rate of self-sufficiency of food grain and the limitation of farmer's income increase. Rapid development of Korean economy has brought labor shoriage in rural farming sector. Accordingly farm mechanization is an important agricultural policy to hike labor productivity and to save production costs of rice farming. The expected economic benefits of the drainage improvement project are derived from increasing land productivity, expanding double cropped area and farming the farm mechanization base in paddy fields. The economic and financial rate of return of the project are considered very important decision making criteria for project implementation by resource allocation. Therefore this study covered benefit and cost analysis of the sampled area, the estimated financial rate of returns in $Buy{\check{o}}$ and Jinsung are represented 15% and 51% respectively and the economic rate of returns in both project area are also showing 1% and 26% respectively. The rate of return of the projects has showed an outstanding variance according to the locational and natural characteristics of the project area. As showing the above economic rate of return, $Buy{\check{o}}$ is very low Jinsung is very high. But the financial rate of return of both projects are considered comparatively high. Cosequently, the drainage improvement projects should be promoted from the view point of farm income increase to make narrow the income gap between rural and urban incomes and farm mechanization to solve labor shortage in the rural area.