• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.11a
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• pp.3-31
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• 1997

Water has always played a significant role in the lives of people. In urbanised Rome, with its million people. sophisticated supply systems developed and then fled with the empire. only to be rediscovered later But it was the industrial Revolution commencing in the eighteenth century that ushered in major paradigm shifts In use and altitudes towards water. Rapid and concentrated urbanisation brought problems of expanded demands for drinking supplies, waste management and disease. The strategy of using water from local streams, springs and village wells collapsed under the onslaughts of rising urban demands and pollution due to poor waste disposal practices. Expanding travel (railways. and steamships) aided the spread of disease. In England. public health crises peaks, related to water-borne typhoid and the three major cholera outbreaks occurred in the late eighteenth and early nineteenth century respectively. Technological, engineering and institutional responses were successful in solving the public health problem. it is generally accepted that the putting of water into pipe networks both for a clean drinking supply, as well as using it as a transport medium for removal of human and other wastes, played a significant role in towering death rates due to waterborne diseases such as cholera and typhoid towards the end of the nineteenth century. Today, similar principles apply. A recent World Bank report Indicates that there can be upto 76％ reduction in illness when major water and sanitation improvements occur in developing countries. Water management, technology and thinking in Australia were relatively stable in the twentieth century up to the mid to late 1970s. Groundwater sources were investigated and developed for towns and agriculture. Dams were built, and pipe networks extended both for supply and waste water management. The management paradigms in Australia were essentially extensions of European strategies with the minor adaptions due to climate and hydrogeology. During the 1970s and 1980s in Australia, it was realised increasingly that a knowledge of groundwater and hydrogeological processes were critical to pollution prevention, the development of sound waste management and the problems of salinity. Many millions of dollars have been both saved and generated as a consequence. This is especially in relation to domestic waste management and the disposal of aluminium refinery waste in New South Wales. Major institutional changes in public sector water management are occurring in Australia. Upheveals and change have now reached ail states in Australia with various approaches being followed. Market thinking, corporatisation, privatisation, internationalisation, downsizing and environmental pressures are all playing their role in this paradigm shift. One casualty of this turmoil is the progressive erosion of the public sector skillbase and this may become a serious issue should a public health crisis occur such as a water borne disease. Such crises have arisen over recent times. A complete rethink of the urban water cycle is going on right now in Australia both at the State and Federal level. We are on the threshold of significant change in how we use and manage water, both as a supply and a waste transporter in Urban environments especially. Substantial replacement of the pipe system will be needed in 25 to 30 years time and this will cost billions of dollars. The competition for water between imgation needs and environmental requirements in Australia and overseas will continue to be an issue in rural areas. This will be especially heightened by the rising demand for irrigation produced food as the world's population grows. Rapid urbanisation and industrialisation in the emerging S.E Asian countries are currently producing considerable demands for water management skills and Infrastructure development. This trend e expected to grow. There are also severe water shortages in the Middle East to such an extent that wars may be fought over water issues. Environmental public health crises and shortages will help drive the trends.

• Journal of Soil and Groundwater Environment
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• v.18 no.4
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• pp.19-31
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• 2013

To figure out the decay characteristics of naturally occurring radionuclides, eight sampled groundwaters from a monitoring borehole having high levels of uranium and radon concentrations in a two mica granitic area have analyzed by liquid scintillation counters (LSC) for over 1 year. In December 2011, three groundwater samples (DJ1, DJ2, DJ3) were obtained from each aquifer system located at -20 m, -40 m, -60 m of the monitoring borehole below the ground surface, respectively. Five samples (DJ4, DJ5, DJ6, DJ7, DJ8) were additionally gained from each aquifer positioned -20 m, -40 m, -60 m, -100 m, -105 m of the borehole in February 2012, respectively. Temporal variation characteristics of uranium and radon concentrations have showed over maximum 2.1 times and 1.4 times fluctuations of the values in the same sampling intervals over time, respectively. The intervals of -40 m and -105 m in the borehole have the highest values of uranium and radon concentrations, respectively. This may imply that the concentrations of naturally occurring radionuclides such as uranium and radon in groundwater have been changed over time and indicate that the qualities of groundwaters from the aquifers developed at each interval in the borehole are different each other. This discrepancy, moreover, could be caused by behaviour differences between uranium which is in ionic status having a half life of 4.6 billion years and is transported along with the flowing groundwater, and radon which is in gaseous status having a 3.82 day's half life in the aquifer systems. Physicochemical characteristics of groundwaters from the aquifer systems could be identified by the results of the on-situ measuring items such as pH and Eh, and the major ionic contents. The CPM values of eight groundwater samples analysed by LSC over one year have shown not to follow the theoretical decay curve of the radon. The CPM values of the samples have ranged from 2 to 7.5 after it had passed two months when the theoretical CPM values of the radon started zero since the initial analysis. Alpha and beta particle spectrums have shown the peaks of radium-226, however they have not revealed any peaks of radon and it's daughter products such as polonium-218 and 214, bismuth-214 for the late stage of the analysis. This implies that the groundwater from the borehole may contain radium-226 having a half life of 1,600 years which decays continuously.

• Journal of the Korean Wood Science and Technology
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• v.38 no.3
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• pp.223-229
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• 2010

In this study diverse dehydrogenative polymers (DHPs) were synthesized with three precursors of native lignin [p-coumaryl alcohol (PCA), coniferyl alcohol (CA), sinapyl alcohol (SA)] in the presence of horseradish peroxidase (HRP, EC. 1.11.1.7)/$H_2O_2$. To compare the structural features between DHPs and native lignin, the DHPs as well as pine/poplar milled wood lignins were simultaneously subjected to gel permeation chromatography (GPC) to determine average molecular weights and derivatization followed by reductive cleavage (DFRC) to investigate the frequency of ${\beta}$-O-4 linkage. The highest yield of DHP was measured to 71% when CA was solely injected (G-DHP) and the yield of H-DHP was 42%. However, single injection of SA could not form any polymer in this system. The average molecular weights of DHPs were ranged between 3,000~4,700, which were only 1/2 fold compared with that of pine MWL (G-type lignin: Mw 7,340) and 1/3 scale compared with that of poplar MWL (GS-type lignin: Mw 13,250). DFRC analysis revealed that the formation of ${\beta}$-O-4 linkage during dehydrogenative polymerization was the highest in the GS-DHP with ca. 502 ${\mu}mol$/g, which was, however, remained to only 50% compared to that in poplar MWL (1107 ${\mu}mol$/g). The ${\beta}$-O-4 linkage was estimated to ca. 286 ${\mu}mol$/g In the G-DHP, which was twice as much as that of H-DHP(127 ${\mu}mol$/g). Similar to GS-DHP, only half amount of ${\beta}$-O-4 linkage, compared to pine MWL, was formed during in vitro polymerization of CA by horseradish peroxidase/$H_2O_2$.

• Journal of the Korean Institute of Gas
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• v.23 no.6
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• pp.90-96
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• 2019

Natural gas has been regarded as one of major alternative fuels, because of the increment of mining shale gas and supplying PNG(Pipeline Natural Gas) from Russia. Thus, it needs to broaden the usage of natural gas as the increasing its supplement. In this situation, application of natural gas on the transport area is a good suggestion to reduce exhaust emissions such as CO₂(carbon dioxides) and soot from vehicles. For this reason, natural gas can be applied to SI(spark ignition) engines due to its anti-knocking and low auto-ignitibility characteristics. Recently, since turbocharged SI engine has been widely used, it needs to apply natural gas on the turbocharged SI engine. However, there is a major challenge for using natural gas on turbocharged SI engine, because it is hard to make natural gas direct injection in the cylinder, while gasoline is possible. As a result, there is a loss of fresh air when natural gas is injected by MPI (multi-point injection) method under the same intake pressure with gasoline-fueled condition. It brings the power reduction. Therefore, in this research, intake pressure was increased by controling the turbocharger system under natural gas-fueled condition to improve power output. The goal of improved power is the same level with that of gasoline-fueled condition under the maximum torque condition of each engine speed. As a result, the maximum power levels, which are the same with those of gasoline-fueled conditions, with improved brake thermal efficiency could be achieved for each engine speed (from 2,000 to 6,000 rpm) by increasing intake pressure 5-27 % compared to those of gasoline-fueled conditions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.5
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• pp.1135-1146
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• 2015

This thesis aims to improve the safety of bicycle traffic for activating the use of bicycle, main means of non-powered and non-carbon transportation in order to cope with worldwide crisis such as climate change and energy depletion and to implement sustainable traffic system. In this regard, I analyzed the problem of bicycle roads currently installed and operated, and developed the bicycle accident forecasting model. Following are the processes for this. First, this study presented the current status of bicycle road in Korea as well as accident data, collect the data on bicycle traffic accidents generated throughout the country for recent 3 years (2009~2011) and analyzed the features of bicycle traffic accidents based on the data. Second, this study selected the variable affecting the number of bicycle accidents through accident feature analysis of bicycle accidents at Jeollanam-do, and developed accident forecast model using the multiple regression analysis of 'SPSS Statistics 21'. At this time, the number of accidents due to extension per road types (crossing, crosswalk, other single road) was used. To verify the accident forecast model deduced, this study used the data on bicycle accident generated in Gwangju, 2011, and compared the prediction value with actual number of accidents. As a result, it was found out that reliability of accident forecast model was secured through reconciling with actual number of cases except certain data. Third, this study carried out field survey on the bicycle road as well as questionnaire on satisfaction of bicycle road and use of bicycle for analysis of bicycle road problems, and presented safety improvement measures for the problems deduced as well as bicycle activation plans. This study is considered to serve as the fundamental data for planning and reorganizing of bicycle road in the future, and expected to improve safety of bicycle users and to promote activation of bicycle use as the means of transportation.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.676-683
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• 2007

In an attempt to develop an efficient method for the propagation of mature Prunus yedoensis (45 to 55 years old), green wood cuttings from normal branch and sprouts branch were treated with three different kinds of auxin (Rootone < 1-naphthylacetamide 0.4% >, IBA 100 ppm, and control and two different kinds of fog systems (0.9 L/min. and 0.54 L/min.). The Rootone treatment showed higher values in the percentage of rootings (PR) and the mean number of roots per cutting (NR) than the IBA treatment in the early stage. However, in the late stage, the values of PR and NR in the Rootone treatment become lower than those in the IBA 100 ppm treatment. On the other hand, root development ceased 62 days after taking cuttings for all of the treatments. The IBA 100 ppm treatment showed the best performance in root development (PR= 89.5%, NR = 6.5, LR=6.4 cm). The values of PR (76.5%) and NR (6.4) in the 0.9 L/min. of fog treatment was higher than those (PR = 71.7% and NR = 5.4) in the 0.54 L/min. of fog treatment. The cuttings from sprouts (PR: 74.8%, NR: 5.9, LR: 5.7 cm) showed slightly better performance in rooting rate that the cuttings from shoots (PR : 73.3%, NR: 5.9, LR: 5.4 cm). Statistically significant interactions were presented among most of the different combinations of three factors (auxin treatments, fog treatments, and types of cuttings). The PR showed the highest value of 98.0% in the combination of cuttings of shoots+IBA 100 ppm+0.54 L/min. fog treatments. In case of NR, the cuttings from normal branch showed a higher value than the cuttings from sprouts branch under the fog treatment of 0.9 L/min., while this tendency was reversed under the fog treatment of 0.54 L/min.. The perigon development of roots, which reflects the number and the direction of roots, was best in the IBA treatment (85.6%).

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.6
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• pp.81-90
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• 2009

This study seeks those elements that form a sense of place in Yen-Ben Street, which represents a typical ethnic enclave in Seoul, to provide a basic resource in the creation of an urban landscape that can provide a positive space for cultural diversity. The results of the study can be summarized as follows: First, the element of a physical environment that develops a sense of place was in fact the poor dwellings that correspond to the economic condition of Korean Chinese. While this element has a negative cognition to outsiders, Korean Chinese feel positively toward it. Secondly, signboards were a physical element of sense of place which retains cultural identity as a means of communication inside the community. Thirdly, it was found that activities such as shopping, recreation, and the exchange of information that are found in the pursuit of daily life act as an essential element in the formation of a sense of place even more than architectural elements. Fourthly, the appropriation of space by Korean Chinese and the isolation from the surroundings were obvious. This isolation is perceived as a negative sense of place formation to outsiders in Yen-Ben Street. Fifthly, the aspects of cultural dualism, mingling the concepts of home country, language, writing, and food have also affected the formation of a sense of place in the area. Sixthly, transience was a prominent phenomenon of Yen-Ben Street and is strengthened by illegal immigration. Although transience causes negative impacts such as in a lack of concern for the residential environment, it acts as a positive factor in the sense of place by mitigating uneasiness, and strengthening insider ties and cooperation.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.3
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• pp.21-32
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• 2009

As an alternative for restoring a sense of community which has been broken up due to urban residence redevelopment, this study focuses on structural characteristics according to physical location of central squares in apartment complexes. Central squares do not simply function as inner-aiming and self-completed spaces for the residents, but their role can be expanded to a core location which encourages neighbors to communicate and interact with each other. The suppositions for this study are as follows. Structural characteristics according to the physical locations of the central squares in apartment complexes affect apartment residents' openness toward their neighbors and non-residents' accessibility to the square. At the same time, it influences the sense of community. In addition, psychological distance which is represented as psychological openness and accessibility forms a reciprocal relationship with the sense of community. For the study, we first categorized central squares as either open-structure or closed-structure based on how accessible it is from outside the apartment complex. According to these types of central squares, Sillim Prugio, Banghak Deasang Town Hyundai, Gwanak Prugio and Banghak Samsung Raemian 1 which have similar conditions and different structures were selected as sites of the study. Then each apartment complex was classified by apartment residents and non-residents so that eight groups were prepared for the survey. The results of the questionnaire survey especially regarding measuring the sense of community, psychological openness and accessibility indicated that the suppositions were right. Hence, the sense of community, psychological openness and accessibility are high in a central square with an open-structure while high standards of psychological openness and accessibility guarantee a positive sense of community. This study is meaningful in that it verifies that the physical location of central squares is reciprocally related to psychological openness, accessibility and a sense of community. At the same time, this study may serve as theoretical grounds for the planning and construction of practical central squares.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.5
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• pp.1-12
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• 2014

Recently, the reenaction of place's memories that were considered sense of place based on its historical and structural characteristic were assumed important topics for recovering and making the park from industrial sites, such as factory, industrial complex, industrial city, labor residential development, landfill, etc., to the public all over the world. This research aimed to conduct some preliminary data for making the park's sense of place highly. So, after conducting the structural forms of sense of place for Seoul Forest and Seonyudo Park that were designed and built by considering its place memories actively, park planning and design implications that were considered its sense of place were suggested. The research results those were derived from the structural forms of sense of place for Seoul Forest and Seonyudo Park's are the following. First, the Structural Equation Modeling(SEM) on Seoul Forest and Seonyudo Park were determined that the natural-physical, artificial-physical, and experiential environmental factors' satisfaction of Seoul Forest and Seonyudo Park have an effect on forming the Sense of Place. In addition, the sense of place was affected by the willingness to visit. Second, according to its physical environment, the experiential factors, such as plays, exercises and etc., were more important relatively. Therefore, experiential factors should be considered significantly with physical factors to make the sense of place highly. Third, even the places were under similar category, the factors' and valuables' relative importance were changed. As the results of structural equation modeling said, specific valuables' related with each factors would be differentiated due to the places' characteristics. For example, the results were showed that natural-physical factor was more important than artificial-physical factor in Seoul Forest. On the other hand, artificial-physical factor was more important than the natural- physical factor. This research carries some significance for applying a quantitative research method(structural equation modeling) to various place to conduct the sense of place's structural model, for suggesting relative specific methods to make the sense of place, and for being a step forward to substance of sense of place. If further studies conduct focusing on various places to draw the forming models of sense of place that were based this research's analysis methods and results, those researches would contribute to make the urban place meaningful, characteristically and affectionately. Furthermore, those researches would contribute in making a humane and competitiveness city.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.2
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• pp.11-26
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• 2013

Designing large parks such as Yongsan Park requires the open-ended process-oriented design approach in complex layers rather than the conventional self-completed master plan method. This study aims to examine the characteristics of process-oriented design in the eight invited entries of "International Competition for the Master Plan of the Yongsan Park, Korea"(2012). For this purpose, it analyzed each entry according to three criteria: objects of process-oriented approach, time factor and its features of phasing plan, and presentation method of the process. This analysis can not only critically review the current level of the process-centered design methodology but also suggest strategic future directions for Yongsan Park. The objects of process-oriented design in the eight works were order of physical space development, restoration process of ecosystem, recovering process of publicity, and economic operation and management. Main considerations in the objects were connections to adjacent urban fabrics, links to regional green and water system, reuse of existing buildings and infrastructures in the site. The temporal criteria of the phasing plan had two aspects. One was planning a certain time and period, and the other was just establishing an order of phases. Most of the presentation method of process was the phasing plan, but some of the entries suggested a scenario plan. The eight works of "International Competition for the Master Plan of Yongsan Park" did not attempt process-oriented designs entirely and completely. Rather, they tried to introduce the phasing plan as part of a process-centered design. Also, they took an eclectic approach between master plan and process-oriented design instead of rejecting the conventional master plan approach.