• Title/Summary/Keyword: Curing age

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A Transcultural Study for Testing Models of the Treatment-seeking Behaviors in Patients with Rheumatoid Arthritis (류마티스 관절염 환자의 치료행위 모형 검증을 위한 횡문화적 비교연구)

  • Lee, In-Sook;Lee, Eun-Ok;Eun, Young;Wilkie, Diana J.;Belza, Basia
    • Journal of muscle and joint health
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    • v.6 no.2
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    • pp.253-277
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    • 1999
  • Patients with chronic disease have various treatment patterns because it shows a progressive degenerative feature. Especially various physical and emotional problems of the rheumatoid arthritis patients leave them shopping around various types of treatment. According to previous studies, over 70% of patients with arthritis experienced the traditional oriental medicine or folk remedies simultaneously with medical treatment within one year after the onset of disease. The purposes of this study are 1) to compare the patterns of treatment-seeking behaviors between Korean arthritis patients and Americans ; and 2) test two models of treatment-seeking behaviors by path analysis, one for early treatment-seeking behavior model(ETBM) and the other is chronic treatment-seeking behavior model (CTBM) in Korean sample. The interview survey was performed to 133 RA patients with structured questionnaire at out-patient clinic or public health center. Patients characteristics such as age, duration of disease were similar in two countries except higher educational background in Americans. There were no patients using only alternative therapies or no medical treatment in the US. Most of the American patients have chosen both medical treatment and alternative therapy, while the Koreans less than American. In Korea, combined treatment group usually consists of the people who are younger, more educated and higher economic status than the characters of other groups in early or chronic stages. In early stage, they tend to have strong belief of curing from the disease, satisfy the relationship with their physicians and comply with direction of the medical professional. The paths of two models were explained by 70% in ETBM and 33% in CTBM. When the models were modified, almost all paths of the CTBM were the same as the previous one, but direct determinant factor was changed from the relationship with physicians to the lay referral system in chronic model. These two models' explanation powers became 94% and 88%, respectively. The attitude or perception of disease, lay referral system and the relationship with medical personnel are the main determinants of treatment-seeking behaviors.

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A Study on the Properties of Concrete for the Improvement of Early Strength (조기강도(早期强度) 증진(增進)을 위한 콘크리트의 강도특성(强度特性)에 관(關)한 실험적(實驗的) 연구(硏究))

  • Kim, Seong Wan;Sung, Chan Yong;Seo, Chong Kug
    • Korean Journal of Agricultural Science
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    • v.14 no.2
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    • pp.345-357
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    • 1987
  • This study was performed to obtain the basic data which can be applied to improve the early strength of concrete. The results obtained were as follows; 1. In case that water reducing-set accelerating agent was added 0.75% of the weight of cement, the weight of water was reducd 10%. And $CaCl_2$ did nearly not have an effect on the w/c ratio. 2. Compressive strength and tensile strength increased 25%, 43%, respectively, in case that $CaCl_2$ was 2.0% of the weight of cement, and showed 120%, 140%, respectively, in case that water reducing-set accelerating agent was 0.75% of the weight of cement. 3. In case of steam curing at $60^{\circ}C$, the strength increased with the ages. At $100^{\circ}C$, the increase of strength in 1 age was two times as compared with plain concrete. After 7ages, the strength was similer to plain concrete. 4. The relationship between compressive strength and tensile strength was linear and was highly significant in cases of plain concrete, $CaCl_2$ concrete, C-W concrete, steam cured concrete, respectively.

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A Study on the Status of Utilization of Health Care Institution by Geriatric Patients -Focus on the Utilization of Physical Therapy- (노인환자 보건의료기관 이용실태 분석)

  • Lee, Jong-Sub;Song, Myung-Soo
    • Journal of agricultural medicine and community health
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    • v.22 no.2
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    • pp.277-293
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    • 1997
  • This study was conducted to provide basic materials required to enforce and develop welfare policies, as well as the health system, for the aged, by surveying the status of health care utilized by the daily increasing old population and the importance of receiving physical therapy. Data that need in this research was gathered from over ages of 65, during the period from Jan 4, 1996 to Jan 31, using the inquiries previously made by geriatric researchers and through literatures investigator by this writer. The data were analyzed by $X^2$, Z-test, Likert scale. The findings were as follows : 1) General characteristics of subjects. People in the age group between 65 and 69 were 55.6% and the highest number, while male were 37% and female 63%. Analysis of income group disclosed 60.6% whose monthly income, including the pocket money given by children, was less than 200,000 won. 91.1% of the elderly people surveyed owned houses; only 36.4% live with spouses; while 15.6% live alone. 2) Characteristics with respect to utilization of health care institution. 56% of the total medical institutions used by the elderly people were clinics and the rates of chronic disease and musculoskeletal disease were 73.2%. 3) Characteristics with respect to approach of health care institution. 45.1% of the respondent stated it took 20 minutes to arrive at hospital, and bus accounted for 48.6% of all transportation means used to go to hospital. 4) Degree of cognition with respect to the rights of geriatric patients. (1) There is no financial support from the government for geriatric patients(71.4%). (2) Government financial support is needed for geriatric patients(95.3%). (3) Have never been regionally surveyed or called upon for interviews with respect to treatment desire and problems relating to geriatric patients(87.2%). (4) Health and medical policies for geriatric patients must be established rapidly(98.4). (5) Expansion and construction of specialized medical facilities for geriatric patients such as elderly hospital and medical center are needed(90.2%). (6) Government's welfare policies for the elderly people is insufficient(82.0%) 5) Degree of cognition on importance of physical therapy with respect to geriatric patient. (1) Physical therapy is considered most effective in treating geriatric patients(82.9%). (2) Physical therapists specializing in only elderly people must be need of separately(76.2%). (3) It is desirable for medical specialists to visit geriatric patients at home to provide physical therapy(82.9%). (4) Hospitals specializing in physical therapy for geriatric patient are required(85.6%). Based on the result for this research, the following suggestions are presented to facilitate the utilization of health care institution for the welfare of geriatric patients. Medical facilities such as elderly hospital and geriatric patient's medical center specializing in elderly people must be constructed as early as possible; and home-visiting physical therapist system must be important to treat chronic geriatric patients; our government must establish policies to provide the old ages with means for the health care and curing chronic diseases, and carry out the plans of reasonable distribution and effective untilization of medical resources.

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Autogenous Shrinkage Properties of High Strength Alkali Activated Slag Mortar (고강도 알칼리 활성 슬래그 모르타르의 자기수축 특성)

  • Oh, Sang-Hyuk;Hong, Sung-Hyun;Lee, Kwang-Myong
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.2 no.1
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    • pp.60-65
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    • 2014
  • Recently, lots of researches on alkali-activated slag (AAS) concrete have been carried out to resolve the environmental issues such as recycling by-products and global warming. AAS concrete would have high strength and high level of durability. On the other hand, it is known that large amount of shrinkage occurred in AAS concrete due to rapid alkaline reaction in the early age, and however, the related studies about autogenous shrinkage of high strength AAS mortar are relatively rare. In this study, fresh mortar properties such as flow and setting time, compressive strength and autogenous shrinkage of AAS mortar with W/B=0.40 to 0.50, were measured. AAS mortar was activated with sodium silicate (Ms=1.0) with 5, 6 and 7 % of $Na_2O$. Test results revealed that AAS morar shows larger autogenous shrinkage than OPC mortar and the lower W/B of AAS mortar, the greater autogenous shrinkage. Therefore, the application of appropriate curing and the use of shrinkage reduction admixture would be needed to reduce autogenous shrinkage of AAS mortar.

Durability Assessment of High Strength Concrete with High Volume Mineral Admixture (다량의 광물질 혼화재를 사용한 고강도 콘크리트의 내구성 평가)

  • Baek, Chul-Woo;Kim, Hoon-Sang;Choi, Sung-Woo;Jo, Hyun-Tae;Ryu, Deug-Hyun
    • Journal of the Korea Concrete Institute
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    • v.27 no.6
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    • pp.641-649
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    • 2015
  • The purpose of this study was to assess the durability of high-strength concrete with high volume mineral admixture (HVMAC) derived from previous studies within ternary blended concrete (TBC) and normal concrete (NC). Four durability evaluation types such as chloride penetration resistance, freezing and thawing resistance, carbonation resistance in two pre-treatment conditions, and sulfuric acid and sulfate resistance using 5% sulfuric acid ($H_2SO_4$), 10% sodium sulfate ($Na_2SO_4$), and 10% magnesium sulfate ($MgSO_4$) solution were selected and performed in this study. HVMAC showed the excellent chloride penetration resistance in any age and the freezing and thawing durability close to 100%. In addition, HVMAC affected more reduction in carbonation resistance than TBC. When the curing time was increased, to create a concrete internal organization densely improved resistance to carbonation. HVMAC also showed the most superior in sulfuric acid and sulfate resistance. As the reduction of calcium hydroxide and $C_3A$ to apply a large amount of admixture reduced the swelling and cracking of concrete, the strength reduction and mass change of concrete was found to be small indicated.

Fundamental Study on High Strength and High Durability Cement Concrete Pavement: Part II Strength and Durability Evaluations (시멘트콘크리트 포장의 고강도 고내구성을 위한 기초 연구 : Part II 최적배합콘크리트의 강도 및 내구특성 분석)

  • Yun, Kyong-Ku;Park, Cheol-Woo;Hong, Seung-Ho
    • International Journal of Highway Engineering
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    • v.11 no.3
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    • pp.51-60
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    • 2009
  • This study investigates the fresh state characteristics, strength, chloride ion penetration resistance and freeze-thaw resistance of the suggested high strength-high durability cement concrete pavement. The required workability and air content could be achieved by using an appropriate admixtures. However its dosage should be carefully determined through field trial batches. Compressive strength increased with the increased cement content and, in particular, high cement volume concrete continuously developed strength up to 90 days. No clear relationship, however, existed between flexural strength and cement content. Chloride penetration resistance seemed as a function of curing age rather than the cement content. Freeze-thaw resistance test was conducted using two different coolants, tap water and 4% NaCl solution. When the tap water was used no severe damage was observed up to 300 cycles regardless the air content. Under 4% NaCl solution, specimens of 326kg/$m^3$ cement content showed severe damage with surface scaling. Based on the experimental investigations herein, it is highly recommended that the cement content be greater than 400kg/$m^3$ for strength-high durability cement concrete pavement structures.

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A Study on Chloride Binding Capacity of Various Blended Concretes at Early Age (초기재령에서 각종 혼합콘크리트의 염소이온 고정화능력에 관한 연구)

  • Song, Ha-Won;Lee, Chang-Hong;Lee, Kewn-Chu
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.12 no.5
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    • pp.133-142
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    • 2008
  • This paper studies the early-aged chloride binding capacity of various blended concretes including OPC(ordinary Portland cement), PFA(pulversied fly ash), GGBFS(ground granulated blast furnace slag) and SF(silica fume) cement paste. Cement pastes with 0.4 of a free water/binder ratio were cast with chloride admixed in mixing water, which ranged from 0.1 to 3.0% by weight of cement and different replacement ratios for the PFA, GGBFS and SF were used. The content of chloride in each paste was measured using water extraction method after 7 days curing. It was found that the chloride binding capacity strongly depends on binder type, replacement ratio and total chloride content. An increase in total chloride results in a decrease in the chloride binding, because of the restriction of the binding capacity of cement matrix. For the pastes containing maximum level of PFA(30%) and GGBFS(60%) replacement in this study, the chloride binding capacity was lower than those of OPC paste, and an increase in SF resulted in decreased chloride binding, which are ascribed to a latent hydration of pozzolanic materials and a fall in the pH of the pore solution, respectively. The chloride binding capacity at 7 days shows that the order of the resistance to chloride-induced corrosion is 30%PFA > 10%SF > 60%GGBFS > OPC, when chlorides are internally intruded in concrete. In addition, it is found that the binding behaviour of all binders are well described by both the Langmuir and Freundlich isotherms.

Flowability and Compressive Strength of Cementless Alkali-Activated Mortar Using Blast Furnace Slag (고로슬래그를 사용한 무시멘트 알칼리 활성 모르타르의 유동성과 압축강도)

  • Koh, Kyung-Taek;Ryu, Gum-Sung;Lee, Jang-Hwa;Kang, Hyun-Jin;Jeon, Yong-Su
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.6 no.1
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    • pp.63-71
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    • 2011
  • Portland cement production is under critical review due to high amount of $CO_2$ gas released to the atmosphere. Attempts to increase the utilization of a by-products such as fly ash and ground granulated blast-furnace slag to partially replace the cement in concrete are gathering momentum. But most of by-products is currently dumped in landfills, thus creating a threat to the environment. Many researches on alkali-activated concrete that does not need the presence of cement as a binder have been carried out recently. In this study, we investigated the influence of alkali activator and superplasticizer on the flowability and compressive strength of the alkali-activated mortar in oder to develop cementless alkali-activated concrete using blast furnace slag. In view of the results, we found out that the type and mixture ratio of alkali activator, the type and adding order of superplasticizer results to be significant factors. When cementless alkali-activated mortar using blast furnace slag manufactured with 1:1 the mass ratio of 9M NaOH and sodium silicate, and added superplasticizer before alkali activator in the mixer, we can be secured workability with 180 mm of flow during 1 hours and compressive strength of about 50 MPa under $20^{\circ}C$ curing condition at age of 28days.

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Physical and Mechanical Properties of Polymer Concrete Using Recycled Aggregate (재생골재를 사용한 폴리머 콘크리트의 물리·역학적 특성)

  • Sung, Chan-Yong;Baek, Seung-Chul
    • Korean Journal of Agricultural Science
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    • v.32 no.1
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    • pp.19-27
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    • 2005
  • This study was performed to evaluate the physical and mechanical properties of polymer concrete using unsaturated polyester resin, initiator, heavy calcium carbonate, crushed gravel, recycled coarse aggregate, silica sand and recycled fine aggregate. The unit weight, compressive strength, flexural strength and dynamic modulus of elasticity were decreased with increasing the content of recycled aggregate. The unit weight, compressive strength, flexural strength and dynamic modulus of elasticity were showed in $2,127{\sim}2,239kg/m^3$, 80.5~88.3MPa, 19.2~21.5MPa and $254{\times}10^2{\sim}288{\times}10^2MPa$ at the curing age 7 days, respectively. Therefore, these recycled aggregate can be used for polymer concrete.

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The Effect of Human Appendage Muscle Strength on Increase in Vertical Dimension from Intercuspal Position of Mandible (교두감합위로부터 출발한 수직교합고경의 단계적 증가가 사지 근력에 미치는 영향에 관한 연구)

  • Hong, Dong-Hee;Lee, Sung-Bok;Choi, Dae-Kyun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.19 no.3
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    • pp.169-183
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    • 2003
  • According to our recent investigation that the increase in the occlusal vertical dimension made the appendage muscle strength got higher, the occlusal appliances were made by increasing the occlusal vertical dimension "from the centric relation" position of the mandible. In this experiment, the authors tried to study the change in the appendage muscle strength due to increase in occlusal vertical dimension from intercuspal position(ICP) of mandible with the same subjects and manner as the former experiment. For this study, ten male athletes in a mean age of 23 year who were joined the former study were selected. All the subjects had a complete or almost complete set of natural teeth and reported no subjective symptoms of temporomandibular disorders. Upper and lower casts were mounted on the semi-adjustable articulator at the intercuspal position and a point was marked on the attached gingival area between the right canine and the right 1st. premolar in each upper and lower cast. From the points, the occlusal vertical dimension was increased by 2mm, 3.5mm and 5mm, and then each 10 maxillary type occlusal splint at each 3-increased position were fabricated with heat curing clear acrylic resin. Including the intercuspal position, the 3 kinds of occlusal splints were placed on the subjects individually, and then isokinetic muscle strength on 7 parts of the human appendage which are shoulder, knee, ankle, wrist, forearm, elbow and hip was measured with the CYBEX 6000 SYSTEM (Lumex, NewYork, USA). The results were as follows: The highest mean value in muscular strength was shown at the position of 2mm-increased vertical dimension. The muscle strength during internal/external rotation of shoulder and knee, plantarflexion of ankle, flexion of elbow, and flexion and extension of hip at the increased occlusal vertical dimension position were significantly higher than them at the intercuspal position (p<0.05). Only in view of the increase in the appendage muscle strength, regardless of the way of making the occlusal splints by elevating the occlusal vertical dimension from the centric relation position or intercuspal position, the occlusal splints had an effect on the increase of isokinetic muscle strength at the occlusal vertical dimension which increased within the proper range on the habitual arc of closure.