• Journal of the Korean housing association
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• v.17 no.4
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• pp.65-72
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• 2006

Most of buildings have been deteriorated with time-elapse by reflection of the building location, material, environmental circumstances and so on. The performance would go down and be demolished if anything could not be done after constructed. The maintenance should be required to preserve a decent living condition or improve a inferior condition by various plans and practices. The maintenance plan needs various data such as a repair scope, a repair time, a forecasted cost, a plan of management and so forth. Among the above required data for planning the maintenance, the deterioration characteristics of the building components would be first analyzed. The deterioration pattern would be a key role to affect and make a maintenance plan. In this paper, it aimed at classifying the deterioration patterns of building components. A deterioration pattern would be analyzed between the cumulative repair cost and time-elapse and modeled with these relations. A deterioration patterns are classified into 4 types-a accelerated type, a straight type, a temporary type and a slowly type. As a result of this research, a accelerated type includes window, window frame, general paintings, general water proofing in building components. A straight type includes the lacquer paintings, furnishings in building components and water supply pipe, boiler, sanitaries in mechanical facilities and lighting in electric facilities. Based on these research results, further study should be conducted to include any other components and an estimating model.

• Journal of Sasang Constitutional Medicine
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• v.23 no.3
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• pp.340-350
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• 2011

1. Objectives: This clinical study was conducted to understand the differences between Sasang constitutional types and to identify the physical symptoms presentation specific to each Sasang constitutional type. 2. Methods: In this descriptive study, 2,629 subjects (1,061 Taeeum-type, 683 Soeum-type, 885 Soyang-type) were surveyed between Nov 1, 2007 and Jul 31, 2010. The subjective symptoms experienced by the subjects were collected using a Physical Symptoms questionnaire, and the subjects were interviewed by Sasang specialists who determined the subjects' constitutional type. The data (in crude number and percentage) was analyzed on the general characteristics, Sasang constitutional type, and physical symptoms using the SPSS 17.0 software. The symptomatic presentation in men and women were analyzed on Sasang constitutional distribution using the chi-square test. 3. Results: 1) The physical symptoms specific to each Sasang constitutional type were as follows: 'frequent aphthous lesions in the oral cavity', 'lingering fatigue after sleep', 'headache', 'common cold symptoms presenting as loss of appetite or indigestion', and 'physical deterioration presenting as problems with digestion' in the Soeum type; 'physical deterioration presenting as problems in perspiration' and 'swelling and puffiness' in the Taeeum type; and 'excessive forgetfulness' in the Soyang type. 2) The physical symptoms specific to each Sasang constitutional type in men were as follows: 'Unilateral or bilateral headaches, 'frequent aphthous lesions in the oral cavity', 'common cold symptoms presenting as rhinorrhea or nasal congestion', 'common cold symptoms presenting as loss of appetite or indigestion', and 'physical deterioration presenting as problems with digestion' in the Soeum type; and 'swelling and puffiness' in the Taeeum type. 3) The physical symptoms specific to each Sasang constitutional type in women were as follows: 'common cold symptoms presenting as headaches', 'common cold symptoms presenting as loss of appetite or indigestion', 'physical deterioration presenting as problems with digestion' in the Soeum type; and 'pain in knees', 'redness of eyes', 'dryness of mouth', 'common cold symptoms presenting as coughing', 'physical deterioration presenting as problems in perspiration', 'swelling and puffiness' in the Taeeum type. 4. Conclusions: This study demonstrates that physical symptoms present in constitutional type-specific patterns. Understanding of the personal Sasang constitutional type and systematic, personalized healthcare based on constitutional typology is anticipated to contribute to improved health management strategy.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.7-15
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• 2017

PURPOSES : Infiltration of moisture, polluted material, and deicer into concrete, accompanied by freeze and thaw can cause significant deterioration of concrete pavement. In order to protect concrete from deterioration, it is necessary to prevent the infiltration of these concrete external materials. The moisture-repellent agent, which is a surface treatment and maintenance material added to concrete structures to render them water resistant, has advantages such as prevention of water infiltration and security against air permeation. Nano-coat, which is referred to as silicon hydride, is typically used as a moisture-repellent agent. Therefore, in this study, an attempt is made to use penetration-type Nano-coat as an alternative in order to evaluate its applicability through environmental resistance tests. METHODS : This study aimed to evaluate the applicability of penetration-type Nano-coat, which can provide water repellency to concrete, in concrete pavements, through various environmental resistance tests such as freezing and thawing resistance, chloride ion penetration resistance, and surface scaling resistance tests. The applicability of penetration-type Nano-coat was demonstrated based on the specification of KS F 2711, KS F 2456, and ASTM C 672. RESULTS :In the case of penetration-type Nano-coat applied on sound concrete, an increase in concrete durability was demonstrated by the negligible chloride ion penetrability and the absence of scaling, as revealed by visual observation of the surface, after 50 cycles of scaling resistance test. In addition, test result of the application of penetration-type Nano-coat on deteriorated concrete established that concrete surface pretreated by grinding provided improved durability than non-treated concrete. CONCLUSIONS :This study indicates that penetration-type Nano-coat is applicable as an effective alternative, to increase the durability of concrete structures. In addition, it was known that pretreatment of deteriorated concrete surface, such as grinding, is required to improve the long-term performance of concrete pavement.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.209-212
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• 2006

Until now, sulfate attack is not completely understood. The purpose of this study is to provide a fundamental data to understand deterioration mechanism by sulfate attack. Chemical processes for products formed by sulfate attack were explained in this study. ASTM C1012 test and microstructural observations such as XRD and BSE analysis were carried out to manifest behavior and role of the products formed during sulfate attack. Regarding the dominant causes of sulfate attack, the main deterioration modes could be divided into 3 types; (1) expansive type, (2) onion-peeling type, and (3) acidic type.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.17-27
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• 2012

The purpose of this study is to analyze the trail deterioration condition and to obtain the information for the desirable maintenance and restoration of trail in national parks. The results obtained from this study were summarized as follows; The physical characteristics of trail were surveyed at the total 778 point for 204.5 km in length. As a result, the average degree of trail was $14.6^{\circ}$, average trail width was 1.5m and average bared trail width was 1.1 m. Major deterioration types of trail were trail deepen (37%), root exposed, widen, diverged, rock exposed and slope erosion in order of frequency. Deterioration class of trail were that non-deterioration was 165.34 km (80.9%), heavy class was 9.08 km, middle class was 12.69 km and light class was 17.39 km and the deterioration rate was 19.1%.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.239-244
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• 2022

In this study, the key parameters affecting the deterioration of each track type were derived based on field inspections and laboratory tests. The existing track deterioration model was limited to the ballasted tracks, and the deterioration evaluation of concrete tracks was insufficient. In this study, the laboratory test was performed to evaluate the performance and condition of track components to derive the deterioration factors reflecting the characteristics of various track structures. In addition, through analysis of track maintenance history data, parameters affecting track deterioration and maintenance were derived. The key parameters for presenting a track deterioration model based on the track performance of ballasted and concrete tracks through field inspection, track maintenance history data analysis, and performance test of track components using on-site specimens were identified as track support stiffness, Ballast gravel, track settlement and Resilience pad were presented.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.3
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• pp.73-81
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• 1999

Measurements of ultrasonic signals caused by partial discharges were perlonnrl by using an ultrasonic measurement technique to diagnose the electrical treeing deterioration in an epoxy mold-type power transformer. We also examined the characteristics of tree growth, partial discharge magnitude and ultrasonic pulse number with the increase of the deterioration time. From these results, it was found that the shape of the tree was a branch-type, and the rates of the tree growth were examined when ac voltages of 16[kV] and 20[kV] were applied Ultrasonic pulse number and discharge magnitude were rapidly increased as the length of the tree grows after the middle stage of the deterioration time, and it appeared that ultrasonic pulse number was proportional to discharge magnitude. Attenuation, time-delaying and directivity characteristics of ultrasonic signals propagated into epoxy resin by using ultrasonic oscillation and receiving systems are also re[prted as a basic data of ultrasonic mesasurements in mold-type power transformer.former.

• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.9-13
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• 2015

This paper describes the analysis of deterioration characteristics for connection factor used in grounding system. The connection method of grounding system is specified in IEC standard. In order to analyze the deterioration characteristics for connection factor, deterioration test was carried out when the connection factor was buried in salt water and underground. The test connection factors were C-type sleeve, clamp, and exothermic welding. As a consequence, most of the connection factor was corroded, and the electrical resistance decreased after deterioration. The analytical results can be used to establish the safety of grounding system.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.5
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• pp.669-683
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• 2012

The water supply pipes are buried across wide range of areas, so it is hard to spot them using excavation and takes a large amount of expense. Thus, there is a high risk for direct research and application, accompanying many difficulties in implementation of them. Therefore, it is more economical and convenient to use indirect evaluation variables than direct evaluation of the buried pipes in assessing the degree of pipe deterioration. To assess the degree of pipe deterioration using the indirect evaluation variables, it should be done first to identify how and to what extent they affect the degree of deterioration. This study measured the evaluation variables for pipe deterioration using the pipe endoscope and analyzed the measurement results and the degree of impact on the pipes. In addition, this study attempted to evaluate the adequateness of the pipe deterioration evaluation using the indirect variables based on the analysis results. The evaluation variables measured through the pipe endoscope were the thickness of sediments, size of scale, degree of desquamation and condition of connections. For the indirect evaluation variables, the data such as the property data from GIS pipe network map as well as the material, diameter, age and pipe lining material of the pipe, road type, leakage frequency, average water velocity and water pressure using the leakage repair records was collected. Using the collected data, this study comparatively analyzed the indirect evaluation variables for the degree of pipe deterioration and the results from the pipe endoscope to choose appropriate variables for pipe deterioration evaluation and calculated the weights of the indirect variables on the degree of deterioration. The results showed that the order of the impact of indirect variables on deterioration was pipe age > pipe lining material > road type > leakage frequency > average water velocity with their weights of 0.45, 0.20, 0.15, 0.10, and 0.10, respectively. Conclusively, the results suggest that the measures of sediment thickness, scale size, degree of desquamation and condition of connections are appropriate for the evaluation of pipe deterioration and sufficient for the analysis of the impact of the indirect variables on deterioration.

• Journal of the Korea Concrete Institute
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• v.13 no.4
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• pp.397-405
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• 2001

In clod weather regions, a strong seasonal wind brings sea salts to the land. In addition to it, recently, the spreading amount of deicing salts has increased numerously for purpose of removing snow and ice. Thus the salts environment around concrete structures becomes so severe that various damages of concrete due to applied salts will be brought up. Much of countries such as America, Europe etc. is carried out study for effects of deicing salts on concrete. However, there are not test methods for deterioration of concrete subjected to both freezing-thawing and chloride in Korea. In this study, we carried out test for the compound deterioration subjected to both freezing-thawing and chloride attack, to investigate the effects of sodium chloride on the deterioration of concrete. The test was performed to investigate the effects of cement type, strength and air content on the scaling deterioration of concrete. As a result, the scaling deterioration was accelerated in the presence of salts. And the resistance to scaling was strongly influenced by the type of cement, the strength and air content of concrete.