• The Journal of Engineering Geology
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• v.21 no.4
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• pp.349-359
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• 2011

The consolidation behavior of soft clay is controlled mainly by its compressibility and deformation characteristics. Soil permeability depends on various soil characteristics, including the soil type and anisotropy. The coefficient of permeability of soft clay is determined by using a laboratory test (the Oedometer test) or a piezocone test. The latter test is useful for estimating the permeability characteristics from $c_h$ and $k_h$ by performing an excess pore-pressure dissipation test. This study seeks to validate an existing theoretical formula in applying it to marine clay, and to assess the relation between $k_h/k_c$ and the mechanical properties of soft clay. Piezocone tests and laboratory tests were performed using sediment from the Yellow Sea and from the South Sea near Korea. We compared $k_h/k_v$ values obtained using the piezocone test and using laboratory consolidation tests. The obtained values are similar to the values obtained by Jamiolkowski et al. (M application); therefore, the latter values are recommended to be used as $k_h/k_v$.

• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.29-39
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• 2004

The prediction of landfill settlement is very important for managing land properly, especially in small national land like Korea. It is difficult to express settlement using the consolidation theory because biochemical decomposition is main reason of settlement, and organic materials in landfill are decomposed far long time. In this study, LFG (Landfill Gas) generation characteristics are studied to find long-term settlement analysing model landfills. Two lysimeters are made; one is leachate recycled, and the other is not leachate recycled. The relationship between gas generation and settlement is analysed as a function of time. A mathematical gas generation model is suggested to predict long-term settlement due to biodegradation, and correction coefficient is recommended for long term settlement through model tests. The leachate recirculation system is more effective to accelerate landfill settlement. The appropriate coefficients of gas correction for non-recycled leachate model are 1.4 and 1.7 for recycled system from tests showing 22% of acceleration.

• Journal of the Korean Geosynthetics Society
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• v.7 no.1
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• pp.39-44
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• 2008

Recently, the demand for industrial and residential lands are being increased with economic growth, however, it is difficult to acquire the land for development with good ground condition. For efficient and balanced development of land, new development projects are being carried out not only the areas with inland but those with the soft ground as well. As soft grounds have complex engineering properties and high variations such as ground settlement especially when their strength is low and depth is deep, it needs to accurately analyze the engineering properties of soft grounds and find general measurement for stabilization and economic design and management. Prefabricated vertical drain technology is widely used to accelerate the consolidation of soft clay deposits and dredged soil under the preloading and various types of vertical drain are being used with the discharge capacity. Under field conditions, the discharge capacity is changed with various reason, such as soil condition, confinement pressure, long-term clogging and folding of vertical drains, and so on. Therefore, many researcher and engineer recommend the use of required discharge capacity. In this paper, the experimental study were carried out for two different types of vertical drains by utilizing the large-scale model tests and waste lime.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.292-308
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• 1992

Recently agricultural situations are being placed in unfavourable socio-economic environment as followed by rapid decrease of rural population, poor labor quality and high wages of rural society due to high speedy industrialization of social structure in Korea. In addition to those circumstances, under the UR system to be expected in the early future, free trade of agricultural products will be faced inevitably in Korea. Practically prices of rice as a principle food in this country are expensive about three times compared to those of foreign rice markets, and so how to increase the international competitiveness and food supplies are important problems to be solved rapidly. Accordingly an urgent goal is reduction of agricultural production cost by the improvement of labour productivity as a labour saving and cost down cultivation methods as the direct seeding cultivation in rice. But there are many problems in the direct seeded rice cultivation. The important things to be improved in that cultivation are development of rice varieties with lodging tolerance, effective seedling stand, weed control, irrigation management and fertilizing and so on. Moreover agricultural basis as irrigation facilities, land consolidation and farm machineries must be improved for the stability of rice cultivation in the future.

• Journal of Korean Society of Rural Planning
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• v.3 no.2
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• pp.90-101
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• 1997

The objectives of the study are to identify the issues and problems encountered in Korea's current integrated rural regional development(IRRD) program and to suggest policy remedies to cope with them. Secondary data and materials ate mainly used for the study. Since the mid-1980s, rural settlement planning has been carried out in the Republic of Korea, In the planning process,'scale of economy'perspectives and settlement policy have been emphasized for increasing the efficiency of investment. During the 1990s, rural settlement and major village development projects have been implemented under the rural structure transformation programs. Agricultural structure adjustment projects for land consolidation and sizable farming have been separated from the rural settlement and mojor village development projects. Based on the evaluative analysis for the rural structure transformation policy and program, some problematic issues were raised as follows: (a) lack of integrative control function in the program'(b) weak linkage between living environment improvement and agricultural development projects: and (c) lack of comprehensive village development planning and implementation system. The policy issues to solve the problems were suggested as follows: (a) adoption of bottom-up approach in new IRRD planning and project system : (b) projection of comprehensive development planning and project at the village level; and (c) introduction of new regional agriculture development projects such as direct payment system for farming in less favorable areas and organic farming.

• International Journal of High-Rise Buildings
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• v.6 no.4
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• pp.327-332
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• 2017

This paper discusses several topics associated with the densification caused by supertall buildings and their impact on city systems. The paper covers five key areas where a supertall tower creates a concentration of needs and effects. First, the paper comments on population shifts towards the city and how they affect carbon footprint, utilities infrastructure and transport. The effect of single- and mixed-use towers is discussed in the context of population density. The second section brings the issues of transit, accessibility and master planning into focus. The use and criticality of public transport, cycling and walking is described. Servicing and deliveries using freight consolidation and shared systems is also discussed along with their contribution to the culture of sustainable travel. In the third section the paper reflects on supertall buildings' below-ground utilities and drainage provision, particularly the challenges faced in established city infrastructures. The utilities issues associated with supertall concentration (in land-use terms) compared to equivalent low-rise distribution is also commented on in the context of surface water runoff. In the fourth section, the topic of supertall sustainability is discussed and how city systems need to respond to create desirable and affordable space for occupiers. The changing need for vertical communities, 'stacked neighbourhoods' and the notion of a micro-city is described. Finally, the paper considers the energy consumption and resilience of supertall buildings in the context of basic geometry, façade design, climate and mixed-use benefits as they impact city systems.

• Journal of Korean Society of Rural Planning
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• v.2 no.2
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• pp.81-90
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• 1996

In this paper, the basic planning for the creation of consolidated agricultural institutions of Choongcheongnam -Do and its management schemes were established. These institutions, including rural development office, farmers'training institution, original seeding field of farm crops, agriculturial information center, packing design center, agricultural machinery repair center, agricultural scientific conference hall, agricultural museum, agricultural park, farmers'hall and event plaza, are planned to be created. The required area for the site is 1,246,781 m2. 281-22 Jongkyung-Ri, Sinam-Myun, Yesan-Gun, Choongcheongnam-Do and its surroundings is a proper site for the creation of'consolidated agricultural institution because the actual conditions of the soil, traffic network, irrigation and drainage, tourist routes and human resources are very good. The layout of the facilities that would comprise an agricultural institution was organized in consideration of the functions and roles of each facility and the relationships among facilities in this consolidated agricultural institution. It is desirable that the headquaters of consolidated agricultural institution oversees the management department, the planning $.$ administration $.$ information department, the rural development office, the farmers'training institution, the original seeding field of farm crops and the agricultural park.

• Journal of the Korean GEO-environmental Society
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• v.20 no.10
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• pp.29-38
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• 2019

In stability and settlement management of soft ground, the settlement prediction technology has been continuously developed and used to reduce construction cost and confirm the exact land use time. However, the preexistence prediction methods such as hyperbolic method, Asaoka method and Hoshino method are difficult to predict the settlement accurately at the beginning of consolidation because the accurate settlement prediction is possible only after many measurement periods have passed. It is judged as the reason for estimating the future settlement through the proportionality assumption of the slope which the preexistence prediction method computes from the settlement curve. In this study, ARIMA technique is introduced among time series analysis techniques and compared with preexistence prediction methods. ARIMA method was predictable without any distinction of ground conditions, and the results similar to the existing method are predicted early (final settlement).

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.475-483
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• 2012

Recently, agricultural lands decrease sharply, which was caused by urbanization, land consolidation, road construction, and innovation city construction, etc. In particular, Goyang, Chenan and Wonju city were had severe land use change. Therefore, we analyzed changes of land use, soil properties, and soil information in order to provide the basic soil information and soil management practice in these cities. The results are summarized as follows. The area of crop cultivated land in Korea (2011) was reduced to 17.3ha compared to ones from the previous year (2009). The paddy field decreased by 24.2 ha but, upland field increased by 7.0 ha. The reasons for the reduction of the paddy field were converting paddy field to upland (20.7 ha) > public facilities (3.2) ${\geq}$ building (3.2) > idle land (1.3) > and others (0.9). Other reasons for reduction in the upland field were switching upland to paddy field, (20.7 ha) > land developed (4.5) > and restoration (0.3) respectively. The main reason of converting paddy field to upland was changing from rice to more profitable upland or greenhouse crops. The cropland area (paddy fields, upland, orchard) of Goyang, Cheonan, and Wonju city were reduced to 1,466 ha, 9,708 ha and 6,980 ha respectively. The ratio of cropland area in each city was reduced by 45~25% dramatically compared to upland soil survey project in Korea (1995~1999). These data were compared with MiFAFF statistics data to use for land use cover map of Ministry of environment. But they were differences significantly. Therefore, intensive investigation should be advised throughout the utilization plan. The paddy fields located in small valley in Wonju city were changed into upland or orchard. The drainage classes of soil have been deteriorated because the flows of water were intercepted by road construction and other disturbance to water flows. In particular, paddy fields have been changed to not only upland, orchard, greenhouse cultivation but also to fallow and soil dressing on paddy in Wonju city. The soil suitability classes of paddy field in Wonju innovation city were the 3rd grade for 70.8% of the area and the 4th grade for 29.2%. The soil suitability classes of upland was the 4th grade for 88.7% of the area. Fortunately, good soil suitability classes were not belong to innovation city in Wonju. So, the good farm land should be conserved and revise the related law.

• Korean Journal of Agricultural Science
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• v.23 no.2
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• pp.301-322
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• 1996

This study is first aimed at identifying the possibility of labour saving and production cost decreasing in rice production with respect to seed broad casting technology. Comparison of labour inputs and production costs of rice in-between USA and Korea and recommendation of policy guidelines for the continous rice cultivation are the second objective of this study. Under the WTO system, rice enterprice is the most vulnerable crop in the sense of labour productivity and price competitiveness in the international market. How to adapt labour saving technology and how to decrease production costs are the most imminent problems to be solved in rice production. To achieve the objectives, survey on nine rice enterprice farms were made in Daeho tidal farmland with respect to the size of farm, labour inputs, productivity, farm mechanization and farm land base development. The existing data on labour saving technology by seed broadcasting which had surveyed by Rural Development Administration were collected to compare the surveyed data from Daeho tidal farm land The study results and policy recommendation are summarized as follows; 1. Labour requirements per 10a for rice enterprise farms with seed broadcasting and with transplanting were estimated 11.4 and 18.5hours respectively. 'This above labour inputs were equivalent to 1/3-1/5 of the national average labour inputs of 53.6 hours which were included transplanting and harvesting by machinery. Considering the labour requirement of 1.7 hours per 10a for the USA rice production, Korea rice culture has possibility to decrease labour demand upto USA level of labour inputs. 2. Production cost of rice in Korea were estimated US$4,181 per ha which were higher than that of USA by 3.00 times and production costs per ton were shown as US$313 for USA rice and US$1,018 for Korean rice. 3. Land productivity of rice per 10a in America was reached to 4,325kg and the counterpart of Korea was about 4,181kg in recent year. In the sense of land productivity, both yields of rice were comparable. 4. The price of japonica type rice similar to Korean traditional rice in international market in 1994 was f.o.b US$466 per ton which was equivalent to import parity price of US$830 per ton in domestic market. The price of rice purchased by Korean G't and received by farmers were amounted to US$ 2,013 and US$ 1,663 respectively in the same year. Domestic prices mentioned above were higher than the import parity price as US$830 by 2.0-2.4 times. 5. American rice production competitive to Korean rice was equivalent to 17,012 thousand tons, 1.28% of the world production of rice in 1991 and consumption of rice in America was amounted to 2,633 thousand tons. Exportable quantity of USA rice were estimated as 4,379 thousand tons of which 52.3%, 2,300 thousand tons, were exported indeed in the same year. 6. The quantity of Korean rice produced in 1991 was estimated 1.00% of the world production. The world amount of rice exported in 1991 was reached to 2.45% of the world production of which 34.2% was occupied by USA The remaining quantities of world exported rice were dominated by Tiland, Pakistan and Vietnam where produced indica variety. 7. Under the given technology, labour inputs per 10a for rice production could be possible to save by 70% of the national average labour requirement of 53.6 hours through implmenting complete farm mechanization with land consolidation and on-farm development and improvement of fanning practices like seedbroad casting txchnology etc. On the other hand, prduction costs of rice could be decreased by 10% rather than 49% as target indicated in the Rural Development Counter Measures of Korean Government in 1994 owing to increasing farm mechanization cost and interest on land service with high price. Accordingly production cost of rice per kg could be decreased only by 10% of the 1994 production cost. 8. Rice policy of Korean government in the future should take into account the labour saving technology to solve labour shortage in rural area and to enhance off-farm incomes by creating job opportunities in agro-industrial zones and special production area. On account of the staple food and main energy source for people's health, rice production even encountered vulnerable economic settings should be continued without price distortion policies and discouraging farmer's intention to cultivate rice by importing institutionally the direct income subsidy system.