• Proceedings of the Korea Water Resources Association Conference
• /
• 2005.09a
• /
• pp.492-492
• /
• 2005

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.9 no.1
• /
• pp.112-120
• /
• 2006

It is possible to divide the historical changes of slope revegetation in Japan into five periods as follows; 1) The early period after creation(1927-1948), 2) The spreading period of modern revegetation work with manpower(1947-1958), 3) The spreading period of rapid revegetation technique using exotic grasses with machineries(1959-1985${\dots}$), 4) The spreading period of rapid reforestation technique by fast growing species mainly using leguminous shrub species(1986-1995${\dots}$), 5) The developing period of nature restoration technique using endemic arborous species(1996-). Recently main purpose of slope revegetation has been developing from the erosion protection to the nature restoration in the current of the 5th period. It is said that the role of the Japanese Society of Revegetation Technology(JSRT) is critical to the history of slope revegetation in Japan. 'The tentative guidelines of slope nature restoration' was announced by JSRT in 2004. In the guidelines, it was proposed that the planning techniques of using suitable seeds/plants based on the preservation level at the each construction sites. Moreover, the use of soil seed bank is the new and important study theme in the field of nature restoration. Consequently, at present the importance of advanced monitoring methods for vegetation maintenance and plant sociologic survey to evaluate the plant succession is increasing. Finally, some critical concepts are necessary to develop the field of restoration in Korea as follows; 1) monitoring of constructed sites, 2) ensuring of biodiversity, 3) recognition of slow revegetation and mosaic arrangement in revegetation, 4) reuse and recycle on the construction sites, and 5) promotion of specialist.

• Environmental Engineering Research
• /
• v.16 no.2
• /
• pp.69-79
• /
• 2011

Rapid population growth and land use changes have severely degraded streams across the United States. In response, there has been a surge in the number of stream restoration projects, including stream restoration for mitigation purposes. Currently, most projects do not include evaluation and monitoring, which are critical in the success of stream restoration projects. The goal of this study is to review the current status of assessment methodologies and restoration approaches for streams in Virginia, with the aim of assisting the restoration community in making sound decisions. As part of the study, stream restoration projects data from a project in Fairfax County, Virginia was assessed. This review revealed that the stream assessment methodologies currently applied to restoration are visuallybased and do not include biological data collection and/or a method to incorporate watershed information. It was found from the case study that out of the twenty nine restoration projects that had occurred between 1995 and 2003 in Fairfax County, nineteen projects reported bank stabilization as a goal or the only goal, indicating an emphasis on a single physical component rather than on the overall ecological integrity of streams. It also turned out that only seven projects conducted any level of monitoring as part of the restoration, confirming the lack of evaluation and monitoring. However, Fairfax County has recently improved its stream restoration practices by developing and incorporating watershed management plans. This now provides one of the better cases that might be looked upon by stakeholders when planning future stream restoration projects.

• Journal of information and communication convergence engineering
• /
• v.6 no.1
• /
• pp.15-18
• /
• 2008

WDM is an incredibly promising technique in which multiple channels are operated along a single fiber, providing the facilities of terabit per second bandwidth. Thus, the survivability of WDM networks becomes critical for the success of the next generation internet architecture. Despite the fact that the path-based proactive restoration scheme guarantees 100% restoration as it computes a backup light path while the primary light path is being set up, this method results in additional capacity consumption. In this paper, an ideal technique is proposed that modifies the active multi-backup paths method and results in a better restoration scheme. Based on a theoretical analysis, a new method is shown to reduce the number of hopes as well as the restoration time.

• Journal of architectural history
• /
• v.10 no.2 s.26
• /
• pp.55-71
• /
• 2001

This study reviewed the preservation status of the Early Western Style Architecture in Korea based on the on-site research of church buildings which are registered as National Cultural Properties. I have investigated 21 church buildings regarding the frequency, content and concept of restoration. The results are summarized as follows First, the churches have been restored extensively in every 17 years on the average. Second, the main restorations are replacement of bricks, painting, waterproofing, repair of roof and timber. And the main changes are extension of plan, removal of Interior posts, and replacement of floor. Third, the main concept of restorations are historical restoration(62%), critical restoration(23%), stylistic restoration(14%). Forth, the category of restoration have been changed, that is extending of incompletion (1st stage), functional improvement and extension of the span of life(2nd stage), improvement of facilities(3rd stage), restoration to the original state and conservation(4th stage). Fifth, the issues of repairing techniques are revival and replacement of weathered bricks, the removal of painting, and structural reinforcement. This study will be able to be used as the fundamental materials to improve the techniques of restoration of Early Western style masonry buildings.

• The Korean Journal of Ecology
• /
• v.25 no.1
• /
• pp.1-7
• /
• 2002

The ecological background of a restoration project is complex and difficult to betermine without experimentation. A useful context for experiments is the well-studied process of natural succession, because the factors that drive or inhibit succession are also at work during reclamation (a form of primary succession) and restoration (which often resembles secondary succession). Using experimental studies on urban wasteland reclamation, we have tested for factors that stimulate or inhibit succession during early phases of woodland development in the Northeastern United states. The emphasis has been on mutualisms (seed dispersal, pollination, and mycorrhizae) and microsite limitations in the recruitment, growth, and reproduction of woody plants. Using plantings of seeds, seedlings, and clusters of reproductively mature plants on abandoned landfills, we have observed that (1) soil microsite deficiencies lead to very poor germination (<0.1$\%$) and seedling survival (<0.01$\%$) of most native species; (2) seed dispersal by birds is a significant and reliable source of woody plant recruitment; however (3) proximity effects are strong, with most (up to 95$\%$) of seed rain falling in the vicinity of planted clusters that are closest to putative seed sources; and (4) remnant natural woodlands are critical components of the recruitment process. To emphasize the last point, in one case, we found that the destruction of approximately 50$\%$ of nearby natural woodland vegetation led to a commensurate decline in seed rain. In another case, we found that the species richness of recruits was strictly limited by the species composition of nearby source plant communities, with no evidence of community enrichment by long distance dispersal over 5 years. We conclude from these results that the size and proximity of remnant natural populations are critical considerations when planning reclamation and restoration programs that rely on natural successional processes.

• International conference on construction engineering and project management
• /
• 2015.10a
• /
• pp.339-343
• /
• 2015

To rapidly recover ceased functionality of a facility after a catastrophic seismic event, critical decisions on facility repair works are made within a limited period of time. However, prolonged damage assessment of facilities, due to massive damage in the surrounding region and the complicated damage judgment procedures, may impede restoration planning. To assist reliable structural damage estimation without a deep knowledge and rapid interactive analysis among facility damage and restoration operations during the approximate restoration project planning phase, we developed a prototype of distributed facility restoration simulations through the use of high-level architecture (HLA) (IEEE 1516). The simulation prototype, in which three different simulations (including a seismic data retrieval technique, a structural response simulator, and a restoration simulation module) interact with each other, enables immediate damage estimation by promptly detecting earthquake intensity and the restoration operation analysis according to estimated damage. By conducting case simulations and experiments, research outcomes provide key insights into post-disaster restoration planning, including the extent to which facility damage varies according to disaster severity, facility location, and structures. Additional insights arise regarding the extent to which different facility damage patterns impact a project's performance, especially when facility damage is hard to estimate by observation. In particular, an understanding of required type and amount of repair activities (e.g., demolition works, structural reinforcement, frame installation, or finishing works) is expected to support project managers in approximate work scheduling or resource procurement plans.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.50 no.12
• /
• pp.575-583
• /
• 2001

Dynamic Voltage Restorer(DVR) which is installed between the supply and a critical load can restore voltage disturbances in distribution system. The restoration is based on injecting the same voltages as voltage sags. The ideal restoration is compensation to make the load voltages be unchanged. But voltage restoration involves real power or energy injection and the capability of energy storage is limited. So it must be considered how injection energy can be minimized and voltages can be made close to the voltages before fault. This paper describes conventional restoration techniques, which draw minimum energy from the DVR in order to correct a given voltage sag or swell. And this paper proposes a new concept of restoration technique to inject minimum energy. The proposed method is based on the definition of voltage tolerance in load side. Hence using the proposed method a particular disturbance can be corrected with less amount of storage energy compared to those of conventional methods.

• Journal of Environmental Impact Assessment
• /
• v.18 no.6
• /
• pp.411-417
• /
• 2009

Lately the master plan for the Four Major Rivers Restoration Project has been released by the Ministry of Land and Maritime Affairs and relevant ministries. According to the master plan compared with the interim report made on 15 December 2008, the number of weirs for irrigation has increased from 5 to 16, the amount of dredging has increased from 220 million cubic metres to 570 million cubic metres, and the total cost estimated has increased from 14 trillion won to 22 trillion won. A critical review of the master plan by some research group will be summarized focused upon budget, objectives, securing water resource, dredging, and flood control etc. After various experts' forums and field surveys, it is concluded that the government should implement a joint-research program on assessing the impact of the project together with experts and citizens' groups as co-partners, in order to truly save or restore the four major rivers.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.18 no.6
• /
• pp.73-83
• /
• 2015

The objective of this study is to establish implications for forest restoration planning in North Korea by analyzing spatio-temporal forest changes and detecting bio-physical factors driving forest degraded. We measured the relationship and spatial distribution between shifting cultivation and sparse forest. We also analyzed between degraded forest land and ecological variables by binary logistic regression to find biophysical drivers of forest degradation and deforestation in North Korea. Between the sparse forest and the shifting cultivation, a positive relationship is found (r=0.91) and scattered discontinuously throughout the country (Moran's I = -1, Z score = -13.46 (p=0.000)). The sparse forest showed a negative relationship with the warmest month(bio 9), the coldest month(bio10), and the minimum of soil water contents (swc_min), while the shifting cultivation had a negative relationship with the warmest month(bio 9) and the minimum of soil water contents(swc_min). However, the most critical drivers convert forests into sloping farmland were the three months rainfall in summer(bio8) and the yearly mean of soil water contents. Such results reflect the growth period of crops which overlaps with the rainy season in North Korea and the recent land reclamation of uplands where the soil water contents are maintained with a dense forest. When South Korea aids forest restoration projects in North Korea, in consideration of food shortage due to North Korea's cropland deficiency, terrace farmlands where soil water contents can be maintained should be excluded from the priority restoration area. In addition, an evaluation method for selecting a potential restoration area must be modified and applied based on multiple criteria including altitude and socio-economic factors in the respective regions.