• Title/Summary/Keyword: Deterioration factors

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Role of 'Spot Sign' on CT Angiography to Predict Hematoma Expansion in Spontaneous Intracerebral Hemorrhage

  • Park, Soo-Yong;Kong, Min-Ho;Kim, Jung-Hee;Kang, Dong-Soo;Song, Kwan-Young;Huh, Seung-Kon
    • Journal of Korean Neurosurgical Society
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    • v.48 no.5
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    • pp.399-405
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    • 2010
  • Objective : Patients with spontaneous intracerebral hemorrhage (ICH) presenting within 24 hours of symptom onset are known to be increased risk of hematoma expansion which is closely correlated with morbidity and mortality. We investigated whether tiny enhancing foci ('Spot sign') on axial view of 3-dimensional computed tomography angiography (3D-CTA) source images can predict subsequent hematoma expansion in spontaneous ICH. Methods : During a 2-year period (March 2007-March 2009), we prospectively evaluated 3D-CTA of 110 patients with spontaneous ICH. Based on source images of 3D-CTA, patients were classified according to presence or absence of 'Spot sign'; 'Spot sign' (+) group, 'Spot sign' (-) group. Radiological factors and clinical outcomes were compared between two groups. Results : Hematoma expansion occurred in 16 patients (15%). Mean Glasgow Coma Scale (GCS) score of patients with hematoma expansion was significantly different compared to score of patients without hematoma expansion (5 vs. 9, P < 0.001). Nineteen patients (16%) of 110 ICH patients demonstrated 'spot sign' on 3D-CTA. Among the 'spot sign' (+) group, 53% of patients developed hematoma expansion. Conversely 7% of patients without 'spot sign' demonstrated the hematoma expansion (p < 0.001). Initial volume and location of hematoma were significantly not associated with hematoma expansion except shape of hematoma. Conclusion : Our study showed that patients with hematoma expansion of spontaneous ICH had significant clinical deterioration. And the fact that 'spot sign' (+) group have higher risk of hematoma expansion suggests the presence of 'spot sign' on source images of 3D-CTA can give a clue to predict hematoma expansion in spontaneous ICH.

Evaluation on the Basic Properties of Polyurethane Composite Sheet Reinforced with Non-Woven Fabric (면섬유가 보강된 폴리우레탄계 복합시트의 기초 물성 평가)

  • Kim, Ji-Hyun;Do, Seung-Bae;Park, Jeong-Won;Nam, Gee-Yoong;Chung, Chul-Woo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.05a
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    • pp.238-239
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    • 2017
  • Waterproofing is a very important process in terms of durability of buildings. The materials used for waterproofing work to protect the concrete structure from external deterioration factors. In particular, the waterproofing materials applied to the exterior of the concrete structure have various problems due to changes in the external environment and variables in the construction process. The waterproof layer is repeatedly dried and shrunk according to changes in the external moisture environment, and the surface may be deteriorated due to exposure to long-term sunlight. In the case of the roof waterproofing in the structure, the waterproof layer which does not have a sufficient curing period shows much swelling and floating phenomenon. These defects, such as swelling and lifting, account for most of the defects that occur in the waterproof layer of the concrete slabs. Generally, it is difficult to expect the same level of performance as the initial state even if the waterproofing work is repaired when a defect occurs. Therefore, it is possible to reduce the defects of the waterproof layer such as swelling and lifting by forming a waterproof layer which can be integrated with the concrete surface by using a polyurethane type waterproofing material having a relatively low defective ratio compared to other waterproofing materials. So in this study, the basic properties of polyurethane waterproof sheet reinforced with non-woven fabric are investigated in order to understand field applicability.

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A Study of Crack Shape Analysis based on Properties of Member in Apartment Exterior Wall (부재속성에 따른 균열 형상 분석에 관한 연구 - 공동주택 외벽 균열을 중심으로 -)

  • Kim, Man-Jang
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.3
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    • pp.143-151
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    • 2015
  • The Crack, occurred in the concrete structure, is a major cause of function deterioration such as strength, durability and waterproof. Therefore the need for crack reduction will continue as long as there is concrete structure. But, it is not easy to reduce or prevent crack cause of impact factor of it. There are so many factors of crack such as material, construction and maintenance environment, and structure, and these are acting in combination. So, this study derives a correlation between the cracks and members through reviewing member crack occurred. And member's attribute, related crack, is analyzed by it. It consider that the basic attribute of member is similar when its requirements are similar. Through this study, therefore, foundation of countermeasure of crack will be provided by prediction of crack shape through member's attribute.

Long-Termed Behavior and Durability of Foam-Mixed Concrete Containing Porous Aggregates (다공성 골재를 함유한 기포혼합콘크리트의 장기거동 및 내구특성)

  • Kim, Sang Chel;Yi, Seong Tae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.6
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    • pp.113-123
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    • 2012
  • The technology developed for the decrease of applying loads and self-weight of a structure is to improve conventional Foam Cement Banking Method (FCB) by applying mixed slurry of bottom ash, cement and foams. Since the foam-mixed concrete, which is a major material of the Bottom ash-mixed Light weight concrete Banking method (BLB) developed, contains mineral admixture such as cement, the behavior shows time-dependent deformation and deterioration of durability due to environmental exposure. Thus, this study is subject to figure out the characteristics of long-termed behavior and durability of the developed method by carrying out experiments for schemed parameters, which are considered to be factors affecting mainly on concrete's characteristics from mechanical analysis. As results of tests, it was found that the developed concrete offers higher resistance than conventional foamed concrete in terms of long-termed behaviors associated with drying shrinkage and creep, and durability problems of freeze-thaw and carbonation processes, especially with addition of bottom ash.

Meteorological Data Acquisition System for the Changkyeonggak (장경각 기상 자료 수집 체계)

  • Yu, Byung Yong;Jeon, Chai Ik;Lee, Kang Su;Shin, Kyo Cheol;Pyun, Chong Hong;Kim, Chang Hong
    • Journal of Conservation Science
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    • v.5 no.1 s.5
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    • pp.69-86
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    • 1996
  • More than eighty thousands of wooden printing blocks of the Tripitaka Koreans are accommodated in the Changkyeonggak which consists of two open structured wooden buildings, Peoppojeon and Sudarajang. These blocks are virtually in pristine state even after three quarters of a millennium. The excellent preservation could be attributed to the careful preparation and meticulous finish of the blocks. But the meteorological environment or microclimate should be one of the key factors for the preservation. To keep the blocks intact as it is or at least do not accelerate the deterioration, we should study the blocks and its microclimatic environment supplied by the Changgyeonggak and the topology of the site. As a Part of this effort we designed a computerized meteorological data acquisition system, which can handle up to 4,096 sensors. A partial but operative installation of 16 temperature/humidity sensors was set up in the Peoppojeon. We hope to have a chance to install a full fledged system in the near future for the compilation of the fuller environmental data base.

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Spatial and Temporal Distribution of Epilithic Diatom Communities in Major Harbors of Korean Peninsula (국내 하구역 부착돌말의 시, 공간적 분포에 미치는 몬순의 영향)

  • Kim, Ha-Kyung;Kim, Yong-Jae;Won, Du-Hee;Hwang, Soon-Jin;Hwang, Su-Ok;Kim, Baik-Ho
    • Journal of Korean Society on Water Environment
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    • v.29 no.5
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    • pp.598-609
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    • 2013
  • Spatial and temporal distribution of environmental factors and epilithic diatom communities in major rivers (30 rivers and 58 sampling points) of the Korean peninsula were surveyed each one time before (May) and after the monsoon (October) 2012. The stream of the east harbor (EAST), the south harbor (SOUTH), and the west harbor (WEST) was sampled in order. Over the survey, a total of 284 taxa were classified, and the number of diatom species in each harbor did not show significant changes after the monsoon, but a biomass significantly decreased. Results also showed that EAST deterioration of water quality and chlorophyll-a after the monsoon, was opposite to SOUTH. Five major dominant species including Nitzschia inconspicua, which contained higher biomass over the survey, were common species which widely distributed in brackish water. Indicator Species Analysis showed that a large number of clean water species in EAST and polluted water species in SOUTH and WEST were emerged respectively. In sum, the Asian monsoon significantly decreased a biomass of epilithic diatoms and water qualities over the harbors (lower stream) in the Korean peninsula, but did not change the major species indicating water quality.

Effects of Activity Limitations on the Health-Related Quality of Life and Depression in Osteoarthritis Patients (골관절염 환자의 활동제한이 건강관련 삶의 질과 우울증에 미치는 영향)

  • Lee, Do-Youn;Nam, Seung-Min
    • Journal of the Korean Society of Physical Medicine
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    • v.15 no.3
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    • pp.109-116
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    • 2020
  • PURPOSE: The objective of this study was to provide a basis for the need to apply psychological factors-based rehabilitation programs to osteoarthritis patients by understanding how the limitations on the activities of osteoarthritis patients relate to the health-related quality of life and depression. METHODS: This study assessed 1,994 osteoarthritis patients from the 7th Korea National Health and Nutrition Examination Survey (KNHANES, 2016-2018). The subjects were divided into two categories: with activity limitation and without activity limitation. A Chi-square test and logistic regression analysis were conducted. RESULTS: The EQ-5D index of subjects with activity limitation was .84 ± .16, it was .94 ± .12 in those with no activity limitation (p < .05). The diagnosis of depression was 16.8% and; 8.3% in those with and without activity limitation, respectively (p < .05). There was a significant difference in the odds ratio for each item in the EQ-5D. Moreover, the odds ratio for depression with an activity limitation was 2.171 (1.512 - 3.118) compared with no activity limitation. CONCLUSION: The activity limitation of osteoarthritis patients reduces the health-related quality of life significantly and increases the probability of depression. Therefore, the treatment of osteoarthritis patients should be approached considering the psychological conditions. Moreover, early diagnosis of depressive symptoms is needed to prevent symptom deterioration and increase the compliance with rehabilitation therapy.

The Study of the Roughness of the Pavement on the Bridge Deck and Approach Slab using a 5year(2003 to 2007) Pavement Condition Survey Data (HPMS 데이터를 이용한 고속도로 교량 및 뒷채움구간 평탄성 특성 연구)

  • Park, Sang-Wook;Suh, Young-Chan
    • International Journal of Highway Engineering
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    • v.10 no.3
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    • pp.189-197
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    • 2008
  • Using a 5 year(2003 to 2007) pavement condition survey data from the highway pavement management system(HPMS), the roughness of the bridge deck pavement was analyzed. Based on the result of this analysis, this study tried to identify the factors affecting the deterioration of the bridge deck pavement condition. The data from HPMS indicates that the roughness of the bridge deck pavement is worse than that of the general pavement on the roadbed. The worse roughness of the bridge deck pavement is caused by the settlement of approach slab as well as the surface distress on the bridge deck pavement. In order to improve effectively the roughness of the bridge deck pavement, a management system was established in which not only the regular automated pavement condition survey to check the distress of surface of the bridge deck pavement was adopted but an automated surface profiler to check the degree of settlement of approach slab was applied.

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Effects of Sand Supply and Artificial Floods on Periphyton in the Downstream of a Dam (Yangyang Dam, Korea) (모래 공급과 인공 홍수가 양양댐 하류하천의 부착조류에 미치는 영향)

  • Park, Misook;Lee, Jaeyong;Jung, Sungmin;Park, Chang-Keun;Chang, Kun;Kim, Bomchul
    • Journal of Korean Society on Water Environment
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    • v.28 no.3
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    • pp.418-425
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    • 2012
  • Dam construction in a river can change its hydrological pattern and trap sediments, which results in ecological changes in the downstream. It is a common phenomenon in the downstream of dams to have decreased sediment flow and increased periphyton. Artificial floods and sediment application are suggested as mitigation practices in order to simulate natural process of flood; transporting sediment and sloughing periphyton off. In this study the effects of artificial floods on periphyton were examined by applying sand artificially and discharging water from a dam (Yangyang Dam, Korea). The study area has been suffering from turbidity problems caused by shore erosion of the dam. The accumulation of inorganic sediments and increase of periphyton on the river bottom are the major factors of habitat deterioration in the downstream reaches. Artificial flood and artificial addition of sand was performed in summer and the effects were measured. Piles of applied sands were washed off easily by discharge and it enhanced the periphyton sloughing effect. The removal efficiency of periphyton was 50 ~ 80% within the 2 km reach from the dam. In conclusion artificial floods and sand application can be a good mitigation measure for the habitat rehabilitation after a dam construction in streams.

International PMC Project Competency Enhancement Strategies for Domestic Engineering Companies (국내 엔지니어링 기업의 해외 PMC 사업 역량강화 방안)

  • Lee, Baul;Lee, Changjun;Han, Seung Heon;Lee, Jeonghun
    • 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.