Dredging Material Application Lightweight Foamed Soil Full Scale Test Bed Verification (준설토 활용 경량기포혼합토 실규모 현장 실증 연구)
-
- Journal of Coastal Disaster Prevention
- /
- v.5 no.4
- /
- pp.163-172
- /
- 2018
To propose the design technique and the execution manual of the LWFS(Lightweight Foamed Soil) method using dredged soil, the operation system for the test-bed integrated management, and to establish an amendment for the domestic quantity per unit and specifications, and a strategy for its internationalization. In order to utilize the dredged soil from the coastal area as a construction material, we constructed the embankment with LWFS on soft ground and monitored its behavior. As a result, it can be expected that the use of LWFS as an embankment material on the soft ground can improve the economic efficiency by reducing the depth and period of soil improvement as well as the uses of nearby dredged soil. To verify the utilization of the dredged soil as a material for light-weighted roadbed, soft ground and foundation ground, and surface processing, perform an experimental construction for practical structures and analyze the behavior. It is expected to be able to improve the soft ground with dredged soil and develop technique codes and manuals of the dredged soil reclamation by constructing a test-bed in the same size of the fields, and establish the criteria and manual of effective dredged soil reclamation for practical use. The application technology of the dredged soil reclamation during harbor constructions and dredged soil reclamation constructions can be reflected during the working design stage. By using the materials immediately that occur from the reclamation during harbor and background land developments, the development time will decrease and an increase of economic feasibility will happen. It is expected to be able to apply the improved soil at dredged soil reclamation, harbor and shore protection construction, dredged soil purification projects etc. Future-work for develop the design criteria and guideline for the technology of field application of dredged soil reclamation is that review the proposed test-bed sites, consult with the institutions relevant with the test-bed, establish the space planning of the test-bed, licensing from the institutions relevant with the test-bed, select a test-bed for the dredged soil disposal area.
The purpose of this study is to present the implications of the rural living area setting and rural spatial structure analysis of the rural spatial strategy plan through case analysis. Following the decentralization of autonomy and the promotion of the transfer of state affairs to local areas, some of the general agricultural and fishing village development projects of the Ministry of Agriculture, Food and Rural Affairs were transferred to local areas. In addition, in 2020, the Ministry of Agriculture, Food and Rural Affairs introduced a rural agreement system for 113 cities and counties. However, since the understanding of the field is still low, this study attempted to present implications through a case analysis of the structure of rural space and the establishment of rural living areas in three local governments in Chungcheong. As a result of the study, in the stage of establishing the living zone, it is necessary to comprehensively review the contents reviewed in the analysis of the current status and conditions. However, the two local governments had insufficient interpretation of the axis by function and the establishment of the base area, or were using the upper plan as it was. Second, the source of the data used in the survey on the distribution status of living SOC facilities is unclear. Since the distribution status of living SOC facilities overlaps with accessibility analysis, OD data analysis, and resident survey results and is used as the basis for setting living areas, the data source should be clearly marked, and verification should be possible. Third, amenity (facility) resources were classified and analyzed according to the conditions and characteristics of local governments. The local government that applied the guidelines as they were was A local government, and the remaining local governments conducted surveys and analysis according to the current status. Forth, since the establishment of the rural living area is the minimum unit supported by government policies through future rural agreements, it is necessary to distinguish them based on quantitative standards in the process of establishing them. Only one case area presented clear grounds and standards, and the rest of the case areas presented standards but are based on non-quantitative standards. In order for rural agreements to be sustainable in the future and benefit local residents, it is necessary to use or establish a government-level institution that can collect and produce objective data. In addition, it is necessary to find ways to specify and standardize the standards for setting the living area and specify them in the guidelines.
A drastic development of modern cities and transportation means as part of a rapid industrialization and urbanization for the past half-century has consistently broaden the boundaries of urban dwellers while, at the same time, raising issues as to establishing relationships among them throughout the society following the materialization of modern urban planning. Within the framework of the postmodern concept, there have been consistent efforts to create a community space in appropriate size and, in particular, the concept of New Urbanism and Urban Village that emerged in mid 1800s along with the effort to build a community by building an ideal city provides an important meaning today when people are seeking to restore a healthy community. Against this backdrop, this study aims to explore the concept of community and to determine its optimal scope of implementation in the sense of healing environment under the premise that organizing a healthy city is based on building a solid urban community. The study findings and conclusions are as follows. First, a community is a subject of constant consideration in the process of historical development of the city and has required us to take a variety of strategic approaches and to determine the scope of implementation. Second, the activities of a healthy community have been conducted under various types of environments, including churches, commercial facilities, urban plazas, parks, and streets in various scales, reflecting their unique characteristics. Third, in the process of designing a healthy and sustainable city, determination of location carries significant implications along with building a community of appropriate size, which requires multidisciplinary considerations in addition to functional approaches. Fourth, the composition and design of a modern urban community need to seek practical ways of its implementation within the concept of healing environment.
Bikes have recently emerged as an alternative to carbon neutrality. To understand the demand for public bikes, we endeavored to estimate travel frequency of public bike by considering the intermediate stops. Using the GPS trajectory data of 'Ttareungyi', a public bike service in Seoul, we identified a stay point and estimated travel frequency reflecting population, land use, and physical characteristics. Application of map matching and a stay point detection algorithm revealed that stay point appeared in about 12.1% of the total trips. Compared to a trip without stay point, the trip with stay point has a longer average travel distance and travel time and a higher occurrence rate during off-peak hours. According to visualization analysis, the stay points are mainly found in parks, leisure facilities, and business facilities. To consider the stay point, the unit of analysis was set as a hexagonal grid rather than the existing rental station base. Travel frequency considering the stay point were analyzed using the Zero-Inflated Negative Binomial (ZINB) model. Results of our analysis revealed that the travel frequency were higher in bike infrastructure where the safety of bike users was secured, such as 'Bikepath' and 'Bike and pedestrian path'. Also, public bikes play a role as first & last mile means of access to public transportation. The measure of travel frequency was also observed to increase in life and employment centers. Considering the results of this analysis, securing safety facilities and space for users should be given priority when planning any additional expansion of bike infrastructure. Moreover, there is a necessity to establish a plan to supply bike infrastructure facilities linked to public transportation, especially the subway.
This work attempted to study the properties of expression of ground, the composition of outlook and the implications of the connotative symbolic scenery throughout investigating the properties of expression content and method of the scenery, outlook, viewpoint, natural features for each drawing and intention of making 4 old maps, which had been made in the period of the Great Korean Empire and had been called 'Wansan-dohyoung(完山圖形),' 'Jogyeongdan- bigak-jaesil-dohyoung(肇慶壇碑閣齋室圖形),' 'Jeonju-geonjisan-dohyoung(全州乾止山圖形)' and 'Jogyeongmyo-gyounggijeon-dohyoung(肇慶廟慶基殿圖形),' and analyzing the correlation between their drawings. For this aim, observatory investigation by using a map, on-spot investigation, analysis involving the satellite images and internet were carried out with literature review simultaneously. The result of investigation could be sum up as follows. Gyounggijeon(1410), Jogyeongmyo(1771) and Jogyeongdan(1899), where are the core space to lay the historically firm foundation for securing the fact Jeonju is the home of the Royal Family of Joseon, had been built, fixed and extended for giving legitimacy to the Joseon Dynasty and a part of strengthening of royal authority. And these had played an important role of spiritual mainstay from early in the Joseon Dynasty to the era of the Great Korean Empire and had been managed and maintained continuously. It is grasped that the 4 maps consist of Sanhyuoungdo(山形圖; a kind of a mountain map), which is the map for showing a burial place of Lee Han(李翰), the founder of the Joseon Dynasty, and its auxiliary drawings and these had been drawn intensively to justify dignity and authority of the Imperial Family and the Emperor after the name of country was renamed the Great Korean Empire as a part of national undertaking. In detail, Wansan-doghyoung is the key map for announcing the existence of Jogyeong-myo, Gyounggijeon and Jogyeongdan in Jeonju and informing their locations and Geonjisan-dohyoung is the map of divination based on topography for highlighting the geomantic justification of the founder's mausoleum. Jogyeongdan-bigak-jaesil-dohyooung is the partial map detailing for Geonjisan-dohyoung. Jeonju-geonjisan-dohyoung and Jogyeongmyo-gyounggijeon-dohyoung had employed the binary reduced scale and the bird-eye view method and in the above maps, Geonji Mountain is the main mountain and these maps make an exaggeration of the main geographical features, centering Wangjabong and Euimyoso, unlike the real geographical features. Also, the other main geographical features, which are found in the burial place, are expressed in detail by changing the view. In the point of view of 1 set being consisted of 4 maps, 'Wansan-dohyoung' has the property not only as Gunhyoundo, which Gun and Hyoun mean a unit of the administrative district, respectively and Gynhyoundo is a kind of the map for recording their locations, but also as the map of showing their locations. On the other side, 'Jogyoungmyogyounggijeondohyoung' is a kind of lay-out drawing as a partially detailed map. In addition, it has been found out that 'Jeonju-geonjisan-dohyoung' and 'Jogyeongdan-bigak-jaesil-dohyoung' is not only Pungsu- hyounggukdo having the function of Sanhyoungdo but also a detail drawing. On the base of these properties, it is considered that the functionality as a serial map had been strengthened, unlike the existing old maps.
As a results of researches on the cultivation processes and settlement developments on the Mangyoung river valley as a whole could be have four 'Space-Time Continuity' through a [Origin-Destination] theory model. On a initial phases of cultivation, the cultivation process has been begun at mountain slopes and tributory plains in upper part of river-basin from Koryo Dynasty to early Chosun Dynasty. At first, indigenous peasants burned forests on the mountain slopes for making 'dryfield' for a cereal crops. Following population increase more stable food supply is necessary facets of life inducing a change production method into a 'wetfield' in tributory plains matching the population increase. First sedentary agriculture maybe initiated at this mountain slopes and tributory plains on upper part of river basin through a burning cultivation methods. Mountain slopes and tributory plains are become a Origin area in cultivation processes. It expanded from up to down through the valleys with 'a bits of land' fashion in a steady pace like a terraced fields expanded with bit by bit of land to downward. They expanded their land to the middle part of river basin in mid period of Chosun Dynasty with dike construction techniques on the river bank. Lower part of river cultivated with embankment building techniques in 1920s and then naturally expanded to the tidal marshes on the estuaries and river inlets of coastal areas. 'Pioneer fringes' are consolidated at there in modern times. Changes in landscapes are appeared it's own characters with each periods of time. Followings are results of study through the Mangyoung river valley as a whole. (1) Mountain slopes and tributory plains on the upper part of river are cultivated 'dryfields' by indigenous peasants with Burning cultivation methods at first and developed sedentary settlements at the edges of mountain slopes and on the river terrace near the fields. They formed a kind of 'periphery-located cluster type' of settlement. This type of settlement are become a prominant type in upper part of river basin. 'Dryfields' has been changed into a 'wetfields' at the narrow tributory plains by increasing population pressure in later time. These wetfields are supplied water by Weir and Ponds Irrigation System(제언수리방법). Streams on the tributory plains has been attracted wetfields besides of it and formed a [water+land] complex on it. 'Wetfields' are expanded from up to downward with a terraced land pattern(adder like pattern, 붕전) according to the gradient of valley. These periphery located settlements are formed a intimate ecological linkage with several sets of surroundings. Inner villages are expanded to Outer villages according to the expansion of arable lands into downward. (2) Mountain slopes and tributory plains expanded its territory to the alluvial deposited plains on the middle part of river valley with a urgent need of new land by population increase. This part of alluvial plains are cultivated mainly in mid period of Chosun Dynasty. Irrigation methods are changed into a Dike Construction Irrigation method(천방수리방법) for the control of floods. It has a trend to change the subjectives of cultivation from community-oriented one who constructed Bochang along tributories making rice paddies to local government authorities who could be gather large sums of capitals, techniques and labours for the big dike construction affairs. Settlements are advanced in the midst of plains avoiding friction of distances and formed a 'Centrallocated cluster type' of settlements. There occured a hierarchical structures of settlements in ranks and sizes according merits of water supply and transportation convenience at the broad plains. Big towns are developed at there. It strengthened a more prominant [water+land] complex along the canals. Ecological linkages between settlements and surroundings are shaded out into a tiny one in this area. (3) It is very necessary to get a modern technology of flood control at the rivers that have a large volume of water and broad width. The alluvial plains are remained in a wilderness phase until a technical level reached a large artificial levee construction ability that could protect the arable land from flood. Until that time on most of alluvial land at the lower part of river are remained a wilderness of overgrown with reeds in lacks of techniques to build a large-scale artificial levee along the riverbank. Cultivation processes are progressed in a large scale one by Japanese agricultural companies with [River Rennovation Project] of central government in 1920s. Large scale artificial levees are constructed along the riverbank. Subjectives of cultivation are changed from Korean peasants to Japanese agricultural companies and Korean peasants fell down as a tenant in a colonial situation of that time in Korea. They could not have any voices in planning of spatial structure and decreased their role in planning. Newly cultivated lands are reflected company's intensions, objectives and perspectives for achieving their goals for the sake of colonial power. Newly cultivated lands are planned into a regular Rectangular Block settings of rice paddies and implanted a large scale Bureaucratic-oriented Irrigation System on the cultivated plains. Every settlements are located in the midst of rice paddies with a Central located Cluster type of settlements. [water+land] complex along the canal system are more strengthened. Cultivated space has a characters of [I-IT] landscapes. (4) Artificial levees are connected into a coastal emnankment for a reclamation of broad tidal marshes on the estuaries and inlets of rivers in the colonial times. Subjectives of reclamation are enlarged into a big agricultural companies that could be acted a role as a big cultivator. After that time on most of reclamation project of tidal marshes are controlled by these agricultural companies formed by mostly Japanese capitalists. Reclaimed lands on the estuaries and river inlets are under hands of agricultural companies and all the spatial structures are formed by their intensions, objectives and perspectives. They constructed a Unit Farming Area for the sake of companies. Spatial structures are planned in a regular one with broad arable land for the rice production of rectangular blocks, regular canal systems and tank reservoir for the irrigation water supply into reclaimed lands. There developed a 'Central-located linear type' of settlements in midst of reclaimed land. These settlements are settled in a detail program upon this newly reclaimed land at once with a master plan and they have planned patterns in their distribution, building materials, location, and form. Ecological linkage between Newly settled settlemrnts and its surroundings are lost its colours and became a more artificial one by human-centred environment. [I-IT] landscapes are become more prominant. This region is a destination area of [Origin-Destination] theory model and formed a 'Pioneer Fringe'. It is a kind of pioneer front that could advance or retreat discontinously by physical conditions and socio-cultural conditions of that region.
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70