• Hwankyungkyoyuk
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• v.10 no.2
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• pp.87-100
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• 1997

This research aims to collect informations which is necessary to develop a curriculum for the environmental education of elementary and secondary schools. We developed a questionnaire concerning the present situations of environmental education in schools and needs assessment items about environmental education. The questionnaire were distributed to a sample of elementary and secondary school teachers with diverse grades and locations. The results of our reserch are as fellows: 1. The awareness of key concepts related to environment problems. They are not aware of ecological interdependence but just focus on the result of environmental deterioration 2. The awareness of importance of environmental education: Teachers prefer campaigns or legislations to environmental education. They want to take an Immediate action rather than a fundmental method like education in order to solve environmental problems 3. The awareness of relationships between environmental problems and natural or man-made circumstances: Most teachers emphasize recycle and reuse of the materials such as batteries, papers, plastics, cans. and bottles. but do not teach the importance of ecology. Only science and environment teachers do. 4. Environmentalism or ecology? Ideally teachers accept the importance of ecology, but in reality they cohoose environmentalism. 5. On the content and method of environmental education: Teachers insist that both environmental instruction and practical, first-hand experience should be given to not only elementary but secondary students, and that most of subject matters should deal with environmental issues. 6. On the situations and tasks of environmental education: School teachers indicate that they could not instill positive patterns of conduct toward environment in students. They think that both insufficient in-service training about environment and cooperation among teachers themselves are partially responsible for it.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.864-868
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• 2008

Water transmission and distribution systems play a important role to deliver safe and clean water and are responsible for the most direct impacts of water utilities to customers. Although the performance of WDS(Water Distribution Systems) should be evaluated by a certain standards, interests has not been in WDS and developed due to invisible, hard-working and insufficient information in the evaluation process in Korea till now. The investigations and researches were carried out to develop software to assist the evaluation of WDS with respects to hydraulics, water quality and structural analysis methods. The methodologies have been developed which can be used to estimate the performance to water distribution network and software are implemented by the process. Developed systems are consisted with database, analysis techniques, simulation models, decision support systems and other tools. The concepts and functions are introduced in this paper and the performance index are discussed for accurate assessment of water distribution systems.

• Journal of the Korea Institute of Building Construction
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• v.12 no.2
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• pp.142-151
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• 2012

Despite the changes to demands and perceptions according to building deterioration, most of the previous studies on remodeling have focused on apartment buildings, which are residential buildings. Few studies have been conducted on buildings for general commercial use, or office buildings. Accordingly, this study set out to prepare a set of performance criteria to assess the remodeling feasibility of office buildings. For that purpose, 23 assessment items were devised, their importance was tested, 13 were extracted, and a set of scoring criteria for each item was prepared. Case analysis was conducted to check the reliability of the assessment items and scoring criteria. Through this analysis, it was found that the criteria were reliable.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.1
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• pp.121-132
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• 2018

Korea's construction engineering companies are facing difficulties in deterioration of international construction profitability because they focus on traditional engineering fields such as design and construction supervision. Therefore, it is necessary to strengthen competency of high-add-value engineering field such as Project-Management-Consultancy (PMC). This paper aims to suggest the strategies to enhance the international PMC competency. This study identified the competency factors for international PMC, using Borich needs assessment and Locus for focus model. As a result, step-by-step strategies were suggested according to the competency level in domestic engineering companies. The results of this study will assist Korean engineering companies to consider the important competencies for international PMC projects. Furthermore, enhancement strategies are going to be proper references for domestic engineering companies which prepare the international PMC project.

• Journal of Korean Neurosurgical Society
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• v.47 no.2
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• pp.102-106
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• 2010

Objective : To evaluate the clinical results of gross total resection in the surgical approach to spinal ependymoma. Methods : Between June 1995 and May 2009,13 males and 8 females (mean age 34) diagnosed with intramedullary or extramedullary spinal ependymoma were surgically treated at our centre. The neurological and functional state of each patient were evaluated according to the modified McCormick scale. Results : The average follow-up duration was 54 months (ranging from 12 to 168 months). The locations of the lesions were : thoracic region (4, 19%), lumbar region (7, 34%), cervical region (4, 19%), cervicothoracic region (3, 14%) and conus medullaris (3, 14%). Four patients (19%) had deterioration of neurological function in the early postoperative period. The neurological function of three patients was completely recovered at the 6th postoperative month, while that of another patient was recovered at the 14th month. In the last assessment of neurological function, 20 patients (95%) were assessed as McCormick grade 1. No perioperative complications developed in any of our patients. In one patient's 24-month assessment, tumour recurrence was observed. Re-operation was not performed and the patient was taken under observation. Conclusion : Two determinants of good clinical results after spinal ependymoma surgery are a gross total resection of the tumour and a good neurological condition before the operation. Although neurological deficits in the early postoperative period can develop as a result of gross total tumour resection, significant improvement is observed six months after the operation.

• Smart Structures and Systems
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• v.31 no.4
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• pp.335-349
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• 2023

Bridges constantly undergo deterioration and damage, the most common ones being concrete damage and exposed rebar. Periodic inspection of bridges to identify damages can aid in their quick remediation. Likewise, identifying components can provide context for damage assessment and help gauge a bridge's state of interaction with its surroundings. Current inspection techniques rely on manual site visits, which can be time-consuming and costly. More recently, robotic inspection assisted by autonomous data analytics based on Computer Vision (CV) and Artificial Intelligence (AI) has been viewed as a suitable alternative to manual inspection because of its efficiency and accuracy. To aid research in this avenue, this study performs a comparative assessment of different architectures, loss functions, and ensembling strategies for the autonomous segmentation of bridge components and damages. The experiments lead to several interesting discoveries. Nested Reg-UNet architecture is found to outperform five other state-of-the-art architectures in both damage and component segmentation tasks. The architecture is built by combining a Nested UNet style dense configuration with a pretrained RegNet encoder. In terms of the mean Intersection over Union (mIoU) metric, the Nested Reg-UNet architecture provides an improvement of 2.86% on the damage segmentation task and 1.66% on the component segmentation task compared to the state-of-the-art UNet architecture. Furthermore, it is demonstrated that incorporating the Lovasz-Softmax loss function to counter class imbalance can boost performance by 3.44% in the component segmentation task over the most employed alternative, weighted Cross Entropy (wCE). Finally, weighted softmax ensembling is found to be quite effective when used synchronously with the Nested Reg-UNet architecture by providing mIoU improvement of 0.74% in the component segmentation task and 1.14% in the damage segmentation task over a single-architecture baseline. Overall, the best mIoU of 92.50% for the component segmentation task and 84.19% for the damage segmentation task validate the feasibility of these techniques for autonomous bridge component and damage segmentation using RGB images.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.1 s.53
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• pp.97-105
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• 2009

Development and use of blended cement concrete is gaining more importance in the construction industry with reference to durability mainly due to the pore refinement and reduction in permeability. Cracks play a major role on important parameters like permeability, rate of chloride ingress, compressive strength and thus affect the reinforcement corrosion protection. Furthermore, when a crack occurs in the cover concrete, the corrosion of the steel reinforcement may be accelerated because the deterioration causing factors can pass through the crack. In recent years the effect of cracking on the penetration of concrete has been the subject of numerous investigations. Therefore assessing the service life using blended concrete becomes obviously in considering the durability. In the present study, the corrosion assessment of composite concrete beams with and without crack with of 0.3mm using OPC, 30% PFA, 60% GGBS, 10% SF was performed using half cell potential measurement, galvanic potential measurement, mass loss of steel over a period of 60days under marine environmental conditions and the results were discussed in detail.

• Geomechanics and Engineering
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• v.38 no.5
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• pp.529-539
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• 2024

A high-level nuclear waste (HLW) repository is designed for the long-term disposal of high-level waste. Positioned at depths of 500-1000 meters, it offers an alternative to the insufficient storage space for spent fuels, providing a long-term solution. High-level waste emits heat and radiation, causing structural deterioration, including strength reduction and cracks. Therefore, the use of piezoelectric sensors for structural health monitoring is essential for evaluating the safety of the structure over time. Unlike other structures, the HLW repository restricts human access after the disposal of HLW, rendering sensor replacement impossible. Therefore, it is necessary to assess both the lifespan and suitability of sensors under the disposal conditions in the HLW repository. This study employed an accelerated life test (ALT) to assess the sensor's lifespan under disposal conditions. Failure modes, failure mechanisms, and operational limits were analyzed through accelerated stress test (AST). Additionally, the parameters of the Weibull life probability distribution and the Arrhenius accelerated life model were estimated through statistical methods, including the likelihood ratio test, maximum likelihood estimation, and hypothesis testing. Results confirmed that the sensor's lifespan decreases significantly with the increase in the temperature limit of the HLW repository. The findings of this study can be used for improving sensor lifespan through shielding, development of alternative sensors, or lifespan evaluation of alternative monitoring sensors.

• Journal of the Korean Geotechnical Society
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• v.21 no.4
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• pp.51-63
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• 2005

Concrete pavement may suffer from material deterioration or structural problems, which lead to surface cracks and deflection of a concrete pavement. Degraded concrete pavement, when it is still under operation, should be recovered by an urgent maintenance to avoid the discontinued service leading to the significant traffic problems and economic loss. Seismic techniques are good tools to assess the structural integrity of concrete runway. It is because seismic techniques can evaluate engineering properties nondestructively and quickly and the evaluation can be extended to subgrade. In this study, a series of numerical simulations of stress-wave propagation were performed to verify feasibility of seismic techniques as an assessment tool. Based on the results of the numerical simulation, a framework of using seismic techniques was presented fur the nondestructive integrated assessment fur structural integrity of concrete runway. And the presented framework was applied to $\bigcirc\bigcirc$ concrete runway with surface cracks, which required urgent maintenance, to identify the causes of the surface cracks. The results obtained from the structural integrity assessment were compared with the measurements of the cores collected from the same runway for verification of the presented framework.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.299-305
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• 2019

As the damage factors of the three­storey stone pagoda of the Bulguksa Temple in Gyeongju could cause a reduction in the historical and artistic value and accelerate the deterioration of the stone, an appropriate solution is needed. The aim of stone conservation is to conserve the original shape and convey originality from the ancestors to their descendants. This procedure includes a record of the condition, being available in the future. In particular, the damage assessment could be used in conservational research, educational data, conservational treatment, and preventive data. As a result of quantitative damage assessment, biological damage indicated 159 %, chemical damage 114 %, and physical damage 16 %. The west direction revealed 95 % because of the amount of sunshine, moisture, and expansion of rock. Complex factors and high range damage were observed on the foundation and body of the pagoda. Since the top of pagoda was restored in the 1970s, the state presented a good condition. By doing this, the number of organisms could be reduced by cleaning and the physical damage could be minimized by bonding. On the other hand, continuous monitoring will be needed because there is a possibility of reforming the damage in the future.