The estimation method of economical leakage management target utilized upon planning business for improvement of revenue water ratio in South Korea is presented and applicability of methods developed in this study is assessed through application on site. With a consideration of revenue water ratio in application target area, estimation method of long-term economical leakage management target is applied. Three leakage reduction methods such as replacement of residual aged pipe, leakage investigation and restoration and water pressure management are applied with a consideration of characteristics of site. Due to difficulty of obtaining data, analysis of cost/benefit by leakage reduction methods is performed by applying method of leakages estimation equation among statistical methods. As a result of application, revenue water ratio corresponding to long-term economical leakage management target is 91.6 %.

This study concerned the analysis on the efficiency of the conversion of water tank type supply system to direct water supply system to examine the feasibility of the conversion, as well as the calculation of optimal conversion range that enables the supply of safe, high-quality water at stable pressure in accordance with the standards of water supply facility. The results of this research showed that when converting water supply system from water tank type supply system to direct water supply system, more nodal points could be properly converted and more reduction of electricity usage was expected in case water pressure rather than residence time was fixed. This means that higher efficacy can be obtained by fixing water pressure when converting water supply system. However, since the number of the locations that received on-spot inspection was small and the electricity usage measured was not exclusively by water supply facility, it is difficult to judge that such reduction of electricity usage accurately represents reduced electricity usage by water supply facility alone. therefore, after having secured on-spot information about a larger number of locations in apartment complexes that have converted water supply system, and utilizing information about electricity usage exclusively by water supply facility, the proposed method of this research could be applied to accurately deducing expected reduction of electricity usage by water supply facilities of various other apartment complexes. It is also considered possible to deduce an effective operation method of water supply system by finding out an area that shows low pressure or low residual chlorine concentration in the optimal conversion range of water supply, followed by estimating the proper location of pumping station or the proper chlorine dosage at the power purification plant that supply water to the target area.

It is considered necessary to renewal a considerable number of water supply facilities in Korea because they began to be intensively buried in the period of rapid economic growth. Accordingly, local water providers are required to take measures against this situation, but they have currently been caught in a vicious circle of the lack of budget spent in renewing water supply facilities because county-based small-scale local water supply cannot afford to cover annual expenditures with their revenues from water rates. Therefore, this study developed an optimal renewal planning model capable of achieving a balance of financial revenue and expenditure in local water supply using nonlinear programming and furthermore of minimizing the total cost incurred during the analysis. To this end, this study selected the water supply area located in County Y as a research area to build the financial revenue and expenditure and used Solver function provided by Microsoft Excel to use nonlinear programming. As a result, this study developed an optimal renewal planning model minimizing incurred costs in consideration of 6 items in the financial revenue and expenditure. The optimal renewal plan was modeled according to the available annual budget. As a result, this study proposed SICD, a scenario to minimize total costs from the perspective of water suppliers, and SITS, a scenario to minimize the increase in water rates from the perspective of consumers. It can be said that the method proposed in this study is the core of the optimal financial and renewal plans as a final stage of asset management for water supply facilities. Therefore, it is considered possible for local water providers to use the method proposed in this study according to circumstances for the asset management of water supply facilities.

The waterworks company is in charge of managing water facilities buried underground, and the management has been centered on manholes. However, since there is no standard management manual, it has been impossible to introduce and operate a systemized managing tool by water service providers and managers, and manhole management has been carried out by individual data recording personnel for each water service provider. When the management is carried out individually, the data to be shared by other waterworks managers tend to be privatized, and consequently, it may become a big obstacle to proceed with many civil works such as emergency leak repair, road excavation, replacement of old buildings. This report introduces RFID (Radio Frequency Identification) system which is based on the magnetic field capable of IOT. It also describes the necessity of leveraging the system for smart managing of pipe management record that has been done by hand writing. The RFID system includes RFID marker, data reader, portable computer operating program, and data base server operating program. In this system, the data is managed with a single communication device, and it would be possible to share the information on the underground facilities and water treatment facilities. This RFID technology is expected to provide water service providers with opportunities to develop more scientific and modernized underground facilities information systems.

Profitability of farmers has decreased mainly owing to low price while the gross amount of mushroom production has increased continuously in South Korea. In this regard, analyzing patterns of mushroom consumption is believed to be meaningful. We used a panel data set consisting of 667 families, from 2010 to 2015. Based on the panel data, mushroom consumption patterns of people living in city areas were examined. Multiple descriptive analysis methods and frequency analysis approaches were adopted in this study in terms of time and space dimensions, demographic properties, and purchase behaviors. The findings of this studyshow that mushroom purchase is highly dependent on seasonal events, which implies that the product consumption timing is predictable. In addition, yearly purchase amount patterns reflect that superstores have become the major mushroomtrading venues. This directly supports the need to establish supply chain capabilities for mushroom farmers so that they gain more bargaining power against enterprise-type groceries. Finally, functional features of mushroom can be linked with marketing promotion because purchase patterns demonstrate potential needs for healthcare food in mushroom categories. Based on the analyzed patterns, this paper provides insightful implications for policy makers who want to promote mushroom consumption.

본 연구는 한반도 통일 이후의 수도로서 개성권에 대한 타당성을 풍수적으로 논의하는데 있다. 즉 남북한 중간에 위치하면서 용수가 풍부하고 물류가 편리하면서 통일한반도의 상징성이 깊은 古都개성과 그 인근지 역에 대한 풍수적 타당성을 검토하였다. 또한 개성은 물론 고려왕조와 조선왕조에 의해 천도(遷都) 후보지로 거론되었던, 불일사(佛日寺), 마하갑 (摩河岬), 장원정(長源亭), 백마산(白馬山) 우소궁(右蘇宮), 중흥궐(重興闕)과 흥왕사(興王寺) 이궁(離宮)을 그 연구대상으로 하였다. 위의 장소들을 검토 해 본 결과, 불일사 일대는 수몰되었고, 마하갑(摩河岬)은 국면이 작은데다 그 분지에 영통사(靈通寺)가 복원되었으며, 장원정(長源亭)은 조강(祖 江)까지의 거리가 불과 8백여 미터로 국면이 작고, 백마산(白馬山) 우소궁 (右蘇宮) 역시 당국(堂局)이 협소하며, 중흥궐(重興闕)은 개성권을 벗어나 서쪽으로 치우쳤다. 고려의 성왕(聖王)으로 일컬어지던 문종(文宗)이 실제적인 도읍지로서의 기능을 부여한 만큼, 심혈을 기울여 창건한 흥왕사(興 王寺)는, 사신사(四神砂)와 조산(朝山)이 잘 갖추어져 있고 그 남쪽으로 도시가 발전할 충분한 공간이 있어 입지가 유망해 보이는 바, 실제 현장답사를 통해 통일수도 입지로서의 가능성과 타당성을 심도 있게 검토하는 것이 반드시 필요하다고 본다.

For the asset management of a water pipe network, it would be necessary to understand the extent of the maintenance cost required for the water pipe network for the future. This study would develop a method to draw the optimum cost required for the maintenance of the water pipe network in waterworks facilities to maintain the aim revenue water ratio and to achieve the target revenue water ratio, considering the water service providers’ waterworks condition and revenue water ratio comprehensively. This study conducted a survey with 96 water service providers as of the early 2015 and developed models to estimate the optimum maintenance cost of the water pipe network, considering the characteristics of the water service providers. Since the correlation coefficient of all the developed models was higher than 0.95, it turned out that it had significant reliability, which was statistically significant. As a result of applying the developed models to the actual water service providers, it was drawn that increasing revenue water ratio to more than a certain level can reduce the maintenance cost of the water pipe network by a great deal. In other words, it is judged that it would be the most efficient to secure the reliability of waterworks management by increasing the short-term revenue water ratio to more than a certain level and gradually increase the revenue water ratio from the long-term perspective. It is expected that the proposed methodology proposed in this study and the results of the study will be used as a basic research for planning the maintenance of water pipe network or establishing a plan for waterworks facilities asset management.

In general, polyethylene (PE), polyvinyl chloride (PVC), and ductile cast iron pipes are widely used in the water supply pipeline system. However, they have some disadvantages such as reduced durability due to material degradation, defects in connections, breakage of pipelines, and difficulties in continuous maintenance. To mitigate such problems, recently, research on durable and outstanding corrosion resistant glass fiber reinforced polymer plastic (GFRP) pipe is being actively conducted. GFRP is classified into the flexible pipe and when soil pressure and live load act on buried GFRP pipe, the load acting on the pipe is transferred to the surrounding soil. So, it should review the structural behavior and interaction between buried pipe and its surrounding soil because pipe will support the load with the surrounding soil together at the same time. To apply GFRP pipe for the water supply pipeline system, the structural reliability of GFRP water supply pipe buried underground should be investigated by examining the mechanical properties of GFRP pipe as well as the soundness of the pipe under buried state. The field test of buried pipe is conducted and the results are analyzed and discussed.

This study conducted a survey with 203 single households among men and women in their 20s to 40s who were living in metropolitan areas from October 6 to November 4, 2012 in order to investigate the dietary attitude of the single households. The ratio of single households who had three meals a day regularly was 2.85 points, which was lower than the normal level, and it turned out that those in their 20s and 30s had meals more regularly than those in their 40s did (p<0.001). As for the irregular meal time, most were breakfast (85.9%), and it turned out that they often skipped meals mostly because they did not have time to eat and (41.7%) or because that bothered them (26.0%). 62.6% of the single households did overeating and most of them (39.4%) did overeating because of their irregular meals. Of the single households, women or persons who had lived alone for less than 3 years or more than 7 years cooked at home, more often (p<0.05), and most of them (42%) cooked noodles, easy to cook, but women cooked Korean food-based homemade food such as rice (31.7%) or soup and stew (21.2%), often (p<0.05). It turned out that 36.9% of the single households often ate out about two to three times a day, and as for their favorite eating-out menus, 39.4% were Korean food, followed by Western food (23.8%), flour-based food (13.5%), fast food (9.8%), Chinese food (7.3%) and Japanese food (6.2%). Lastly, as for inconveniences when they ate out, most were the ‘price’ (22.8%), followed by ‘too much amount of food for one person’ (20.2%) and ‘limitations in menu selection’ (19.2%). As a result of this study, it appeared that the single households had an irregular dietary life, often did overeating and often ate out, so it is judged that it would be necessary to develop a variety of nutritionally-balanced HMR food and eating-out menus in a reasonable price range for their healthy dietary life.

In this study, seismic fragility analysis are carried out for the water supply facilities. To consider the uncertainty of ground characteristics, the variability of soil in several cases is considered based on RSM and the winkler Foundation method is adopted to model the ground. Limit state of water supply facilities defined as two steps.: the collapse prevention level and the serviceability level. As an input ground motion for evaluating seismic fragilities, foreign surveyed real earthquakes and artificial earthquakes which can be generated in the Korean peninsula are used. The destruction ability according to peak ground acceleration of an earthquake for the water supply facility is evaluated in this paper. From the analysis results, the probability of failure of the ductile iron pipe and wrapped steel pipe under real earthquakes have shown as upper than the Korean artificial earthquakes. It could evaluate the damage of water supply facilities to an earthquake and could be applied as basic data for seismic design of water supply facilities.

A variety of methods for detecting the location of an underground water pipeline are being used across the world; the current main methods used in South Korea, however, have the problems of low precision and efficiency and the limitations in actual application. On this, this study developed locator capable of detecting the location of a water pipe by the use of an IMU sensor, and technology for using the extended karman filter to correct error in location detection and to plot the location on the coordinate system. This study carried out a tract test and a road test as basic experiments to measure the performance of the developed technology and equipment. As a result of the straight line, circular and ellipse track tests, the 1750 IMU sensor showed the average error of 0.08-0.11%; and thus it was found that the developed locator can detect a location precisely. As a result of the 859.6-m road test, it was found that the error was 0.31 m in case the moving rate of the sensor was 0.3-0.6 m/s; and thus it was judged that the equipment developed by this study can be applied to long-distance water pipes of over 1 km sufficiently. It is planned to evaluate its field applicability in the future through an actual pipe network pilot test, and it is expected that locator capable of detecting the location of a water pipe more precisely will be developed through research for the enhancement of accuracy in the algorithm of location detection.

Although the Hazen-Williams C factors are very important in the design, operation, and maintenance of water supply pipes, sufficient studies for them have been not reported in korea, which are based on experiments or measured data. Because of this, we have estimated C factors by measurement considering constraints in time precise safety diagnosis for multi-regional water supply system were performed. In this study, we confirmed constraints and variables characteristics of Hazen-Williams equation, and collected reliable C factors data of 174 by measurement, and analyzed their characteristics. According to collected data, the average value is 115.35, which is almost equal to the value of design standard or a little higher than it in korea. Also, among the equations suggested to determine C factor in the past, the C factors calculated by Sharp and Walski equation was closest to them in this study. In addition, to analyze collected C factors, use year and pipe diameter having high correlation with them were respectively divided into there categories. Analysis results showed that C factors evidently decreases depending on increases in use year, on the other hand, size of pipe diameter is proportional to value of them. In conclusion, this research showing evaluation and characteristics for C factors based on measured data will be used as practical reference in determining C factor in multi-regional water supply systems at a later date.

Owing to time and cost constraints, new methods that would make it possible to evaluate the safety of the water supply pipeline in a less time- and cost-consuming manner are urgently needed. In response to this exigency, the present study developed a new statistical model to assess the safety of the water supply pipeline using the quantification theory type Ⅱ. In this research, the safety of the water supply pipeline was defined as ‘a possibility of the pipeline failure’. Quantification analysis was conducted on the qualitative data, such as pipe material, coating, and buried condition. The results of analyses demonstrate that the hit ratio of the quantification function amounted to 77.8% of hit ratio, which was a fair value. In addition, all variables that were included in the quantification function were logically valid and demonstrated statistically significant. According to the results derived from the application of the safety evaluation model, the coefficient of determination (R2) between K-region’s water supply pipeline safety and the safety inspection amounted to 0.80. Therefore, these findings provide meaningful insight for the measured values in real applications of the model. The results of the present study can also be meaningfully used in further research on safety evaluation of pipelines, establishing of renewal prioritization, as well as asset management planning of the water supply infrastructure.