• Title/Summary/Keyword: concrete rehabilitation

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Behavior of Hollow Box Girder Using Unbonded Compressive Pre-stressing (비부착 압축 프리스트레싱을 도입한 중공박스 거더의 거동)

  • Kim, Sung Bae;Kim, Jang-Ho Jay;Kim, Tae Kyun;Eoh, Cheol Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.3A
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    • pp.201-209
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    • 2010
  • Generally, PSC girder bridge uses total gross cross section to resist applied loads unlike reinforced concrete member. Also, it is used as short and middle span (less than 30 m) bridges due to advantages such as ease of design and construction, reduction of cost, and convenience of maintenance. But, due to recent increased public interests for environmental friendly and appearance appealing bridges all over the world, the demands for longer span bridges have been continuously increasing. This trend is shown not only in ordinary long span bridge types such as cable supported bridges but also in PSC girder bridges. In order to meet the increasing demands for new type of long span bridges, PSC hollow box girder with H-type steel as compression reinforcements is developed for bridge with a single span of more than 50 m. The developed PSC girder applies compressive prestressing at H-type compression reinforcements using unbonded PS tendon. The purpose of compressive prestressing is to recover plastic displacement of PSC girder after long term service by releasing the prestressing. The static test composed of 4 different stages in 3-point bending test is performed to verify safety of the bridge. First stage loading is applied until tensile cracks form. Then in second stage, the load is removed and the girder is unloaded. In third stage, after removal of loading, recovery of remaining plastic deformation is verified as the compressive prestressing is removed at H-type reinforcements. Then, in fourth stage, loading is continued until the girder fails. The experimental results showed that the first crack occurs at 1,615 kN with a corresponding displacement of 187.0 mm. The introduction of the additional compressive stress in the lower part of the girder from the removal of unbonded compressive prestressing of the H-type steel showed a capacity improvement of about 60% (7.7 mm) recovery of the residual deformation (18.7 mm) that occurred from load increase. By using prestressed H-type steel as compression reinforcements in the upper part of cross section, repair and rehabilitation of PSC girders are relatively easy, and the cost of maintenance is expected to decrease.

Study on the Utilization of Complementary Alternative Therapy in elder Arthritics (노인 관절염 환자의 보완.대체요법 이용실태)

  • Park, Kyung-Sook;Ryoo, Eon-Na;Moon, Kyung-Sun;Lee, Won-Yu;Lee, Sung-Ock;Kim, Myung-Hee;Youn, Mi-Sun;Oh, Jung-Mi;Hwang, Yun-Young;Kim, Hyung-Aee
    • Journal of muscle and joint health
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    • v.10 no.2
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    • pp.142-155
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    • 2003
  • The purpose of this study was to investigate the rate of utilization, kinds and effective complementary-alternative therapy in elder arthritics, and then utilize the results as basic data for nursing intervention for elder arthritics. Study subjects consisted of 157 elder arthritics over 60 years old, data were collected through a structured questionnaire and face to face interviews. Data collection was done from July 2001 to August 2001. Subjects were sampled out from outpatients of department of rehabilitation of a university hospital in S city, outpatients of a local hospital in D city, and outpatient at public heath center in K and S city. Sexual distribution of subjects showed male 19.1% and the female 80.9%. The diagnosis distribution showed degenerative arthritis at 91% and reumatoid arthritis at 8.9% Duration of arthritics was 10 years over by 46.5%, duration of hospital treatment was 1-5 years by 41% The degree of pain by arthritis pointed out a mean point of 3.37 on a 5-point numeric scale 94.2% of subjects have experience complementary-alternative therapies used. Of the kind the subjects used, physiotherapy occupied 38.2%, Oriental medicine 36.3%, physical exercise 35.7%, nutritional therapy 22.3%, animal diet 8.9%, herbal diet 3.8%. The hardest thing due to arthritis represented disability in daily life by 59.8% and the pain problem by 30.5%. In conclusion, results of the study reveal that elder arthritics have used physiotherapy, Oriental medicine, physical exercise. Concrete strategies for nursing intervention about these complementary-alternative therapy are required to the established soon.

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Development of a Diagnosis Manual to Evaluate the Pedestrian Safety in a Neighborhood Using the Mixed Research Method (혼합연구방법을 활용한 근린환경의 보행안전성 진단 매뉴얼 개발)

  • Kim, Jaecheol
    • Journal of Digital Convergence
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    • v.15 no.8
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    • pp.1-14
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    • 2017
  • This study is a descriptive and exploratory one aiming to develop a systematic/diagnostic manual that is necessary for the improvement of the pedestrian safety of a neighborhood and show the practical application and usefulness of the manual through a case study. The diagnostic manual developed on the basis of the previous research review adopted a mixed research method including three investigation tools of map/data analysis using secondary data, field observation by investigators, and resident survey interview. In the case study applying the manual to Changsin-dong, Seoul, the author analyzed the results of the three investigations in integrative ways and showed the usefulness of the manual by systematically deriving the places prone to pedestrian-vehicle accidents and the influencing factors. This study contributes to the practical field in that it provides planners with a systematic tool to diagnose the pedestrian safety in the neighborhood environment while it contributes to the academic field in that it provides the concrete process that empirically compares the differences between different environmental investigative methods and deduce integrative implication from them. In a follow-up study, the author plan to apply the diagnostic manual presented in this study to more cases and improve them to work in various contexts.

The Differences of Naming by Word Frequency, Length, and Animacy in Nonfluent Aphasic Patients (비유창성 실어증 환자의 단어빈도 및 길이, 생물성에 따른 이름대기 수행의 차이)

  • Kwon, Jung Hee;Choi, Hyun Joo
    • 재활복지
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    • v.20 no.1
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    • pp.171-188
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    • 2016
  • The purpose of this study is to investigate effects of three conditions-words frequency, word length, and animacy-on the performance of naming in nonfluent aphasic patients. 15 nonfluent aphasic patients and 15 normal adults were participated in this study. The words consist only of concrete nouns and confrontational naming test was used. The test consisted of 40 questions and the condition of word were frequency(low-frequency/high-frequency), length(1 syllable/3 syllables) and animacy(animate/inanimate). The result of the study was as follows. First, naming was performed better with high-frequency words than with low-frequency words in both groups. Second, naming was performed better with 1 syllable words than with 3 syllable words in both groups. Third, naming performance depending on animacy did not show significant differences in both groups. These results indicate that compared to animacy of word, word frequency and length have bigger influence on the naming, and the difference by word frequency was more pronounced for nonfluent aphasic patients than for normal adults. The results of this study suggest that target word for the assessment and intervention of nonfluent aphasic patients, words frequency should be considered first in clinical setting.

Present State and Conservation Counterplan for the Wetlands of the Tributaries around Namgang-River (남강 주변 습지의 보전 현황과 보전 대책)

  • Ha, Hye-Jeong;Oh, Kyung-Hwan
    • Journal of Wetlands Research
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    • v.12 no.3
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    • pp.21-37
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    • 2010
  • The abiotic factors and the vegetation naturalness of the 13 tributary wetlands around Namgang-River were assessed to investigate the present state and to present the conservation counter plan for the wetland ecosystem of the tributaries. Assessment indices for the abiotic factors were estimated based on the dominant land use types of the riparian zone, ecological function of the upper levee, levee slope structure, artificiality and utilization intensity of the waterfront, artificiality of the revetment structure, diversity of the substrate, and severance of the transverse. The assessment index of Omi-cheon is the highest among 13 tributaries. The second was Banseong-cheon and third was Hyangyang-cheon, followed by Nabul-cheon and Yeongcheon-gang and Sugok-cheon, Jungchon- cheon, and Daegok-cheon in their order and Munsan-cheon got the lowest assessment index. Assessment indices for the vegetation naturalness were estimated based on the vegetation diversity, exotic species dominance, annual herb dominance, naturalness and peculiarity of the vegetation, and species diversity. The assessment index of Omi-cheon is the highest among 13 tributaries. The second was Sugok-cheon and third was Banseong-cheon, followed by Yeongcheon-gang, Jungchon- cheon, Jinae-cheon, Nabul-cheon, and Jisu-cheon in their order, and Yonga-cheon got the lowest assessment index. The grades of the stream naturalness were estimated based on the the naturalness indices for the abiotic factors and the vegetation naturalness. The grades of Omi-cheon is the highest among 13 tributaries as the grade I. Those of Banseong-cheon, Sugok-cheon, Yeongcheon-gang, Nabul-cheon and Jungchon-cheon, Hyangyang-cheon, Jinae-cheon, Jisu-cheon, Daegok-cheone, and Munsan-cheon and Doksan-cheon were grade II in their order, and Yonga-cheon got the lowest as the grade III. It was suggested that restoration of the simple and flat substrate, create the natural vegetation on the levee slope constructed with concrete or stone wall, and rehabilitation of the eco-bridge were demanded to improve the grades of the stream naturalness through the restoration of the tributaries for the diverse aquatic wildlife, high vegetation diversity and species diversity with the vegetation consisted of perennial herbs and trees.