• Title/Summary/Keyword: scale-up factors

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An Experimental Study on the Manufacture Ultra-High Strength Concrete of 1800kg/$\textrm{cm}^2$ Compressive Strength (Part 2 The Experiment on the Manufacture of the U.H.S Concrete) (압축강도 1800kg/$\textrm{cm}^2$의 초고강도콘크리트 개발에 관한 실험적 연구 (제2보 초고강도콘크리트의 제조에 관한 실험))

  • 남상일;김진만;최민수;김규용;최희용;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 1994.10a
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    • pp.171-174
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    • 1994
  • To reduce the size of structural members, high strength concrete has recently been utilized for structure such as ultra-high-rise buildings and prestressed concrete bridges in North America, and its compressive strength has gone up to 1300kg/$\textrm{cm}^2$. In Japan, research on high-strength concrete has been undertaken on a large scale by the national enterprise so-called New RC Project. And high-strength concrete with a design compressive strength over 450kg/$\textrm{cm}^2$ has recently been employed for high rised reinforced concrete building. As a result of the serious land availability situation of metropolitan areas in the world, buildings will become taller, and even higher strengths will be required. In the future, the utilization of high-strength concrete will spread widely through the development of new structural concepts, application of steels of a higher yield stress, silica fume, and other new materials. Considering these circumstance, the aim of this experimental study is to develop ultra-high-strength concrete with compressive strength over 1800kg/$\textrm{cm}^2$ with domestic current materials. There are so many factors which influence the manufacturing of ultra-high-strength concrete. The experimental factors selected in this study are mixing methods, curing methods, water-binder ratio, maximum size of coarse by silica fume. The results of this experimental study show that it is possible to develop the ultra-high-strength concrete with compressive strength over 1700kg/$\textrm{cm}^2$ at 28days, 1800kg/$\textrm{cm}^2$ at 56 days.

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Therapeutic Effect of Gamma Knife Radiosurgery for Multiple Brain Metastases

  • Lee, Chul-Kyu;Lee, Sang-Ryul;Cho, Jin-Mo;Yang, Kyung-Ah;Kim, Se-Hyuk
    • Journal of Korean Neurosurgical Society
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    • v.50 no.3
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    • pp.179-184
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    • 2011
  • Objective : The aim of this study is to evaluate the therapeutic effects of gamma knife radiosurgery (GKRS) in patients with multiple brain metastases and to investigate prognostic factors related to treatment outcome. Methods : We retrospectively reviewed clinico-radiological and dosimetric data of 36 patients with 4-14 brain metastases who underwent GKRS for 264 lesions between August 2008 and April 2011. The most common primary tumor site was the lung (n=22), followed by breast (n=7). At GKRS, the median Karnofsky performance scale score was 90 and the mean tumor volume was 1.2 cc (0.002-12.6). The mean prescription dose of 17.8 Gy was delivered to the mean 61.1% isodose line. Among 264 metastases, 175 lesions were assessed for treatment response by at least one imaging follow-up. Results : The overall median survival after GKRS was $9.1{\pm}1.7$ months. Among various factors, primary tumor control was a significant prognostic factor ($11.1{\pm}$1.3 months vs. $3.3{\pm}2.4$ months, p=0.031). The calculated local tumor control rate at 6 and 9 months after GKRS were 87.9% and 84.2%, respectively. Paddick's conformity index (>0.75) was significantly related to local tumor control. The actuarial peritumoral edema reduction rate was 22.4% at 6 months. Conclusion : According to our results, GKRS can provide beneficial effect for the patients with multiple (4 or more) brain metastases, when systemic cancer is controlled. And, careful dosimetry is essential for local tumor control. Therefore, GKRS can be considered as one of the treatment modalities for multiple brain metastase.

Tabbed Tissue Expanders Improve Breast Symmetry Scores in Breast Reconstruction

  • Khavanin, Nima;Gust, Madeleine J.;Grant, David W.;Nguyen, Khang T.;Kim, John Y.S.
    • Archives of Plastic Surgery
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    • v.41 no.1
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    • pp.57-62
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    • 2014
  • Background Achieving symmetry is a key goal in breast reconstruction. Anatomically shaped tabbed expanders are a new tool in the armamentarium of the breast reconstruction surgeon. Suture tabs allow for full control over the expander position and thus inframammary fold position, and, in theory, tabbed expanders mitigate many factors responsible for poor symmetry. The impact of a tabbed expander on breast symmetry, however, has not been formally reported. This study aims to evaluate breast symmetry following expander-implant reconstruction using tabbed and non-tabbed tissue expanders. Methods A chart review was performed of 188 consecutive expander-implant reconstructions that met the inclusion criteria of adequate follow-up data and postoperative photographs. Demographic, oncologic, postoperative complication, and photographic data was obtained for each patient. The photographic data was scored using a 4-point scale assessing breast symmetry by three blinded, independent reviewers. Results Of the 188 patients, 74 underwent reconstruction with tabbed expanders and 114 with non-tabbed expanders. The tabbed cohort had significantly higher symmetry scores than the non-tabbed cohort ($2.82/4{\pm}0.86$ vs. $2.55/4{\pm}0.92$, P=0.034). Conclusions The use of tabbed tissue expanders improves breast symmetry in tissue expander-implant-based breast reconstruction. Fixation of the expander to the chest wall allows for more precise control over its location and counteracts the day-to-day translational forces that may influence the shape and location of the expander pocket, mitigating many factors responsible for breast asymmetry.

The influencing factors of denture satisfaction in the low income elderly people (저소득층 노인의 의치만족도에 영향을 미치는 요인)

  • Lee, Ji-Hui;Cho, Mi-Hyang;Moon, Deog-Hwan
    • Journal of Korean society of Dental Hygiene
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    • v.15 no.1
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    • pp.73-79
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    • 2015
  • Objectives: The purpose of this study was to investigate the factors influencing on the denture satisfaction in the low income elderly people. Methods: The subjects were 143 elderly people from 60 to 75 years old wearing dentures and receiving consistent follow-up in the public health center in Busan. A self-reported questionnaire was filled out by the elderly people from February 1 to March 1, 2013. The questionnaire consisted of denture satisfaction, social variables, and psychological variables. Data were analyzed by ANOVA and multiple regression analysis using SPSS 18.0. The sociodemographic characteristics included gender, age, and chronic diseases. The recognition of oral health included pronunciation, denture maintenance, mastication ability, and education for denture care. The questionnaire was measured by Likert 5 scale. Results: Gender, chronic disease, denture care instructions, and the self-preception of the oral health after denture treatment were closely correlated with denture satisfaction(p<0.001). Age and the number of repairs were very important factor to denture satisfaction(p<0.05). Elderly women were more satisfied with denture than men and those who had no chronic diseases tended to be more satisfied with denture. Those who received oral care instructions were more satisfied with the denture than those who did not. The younger age group and no repairing prosthetic group tended to be more satisfied with the denture. Conclusions: It is important to provide the denture management services to the low income elderly when they demand the services. The national dental health policy must be focused on connection of the elderly people denture services with the public health center.

Prospective Study on Factors Related to Development in Premature Infants at Six-Months (미숙아로 출생한 영아의 6개월 발달 관련 요인에 대한 전향적 연구)

  • Bang, Kyung-Sook;Kang, Hyun-Ju;Lee, Buhyun;Kwon, Mi-Kyung
    • Child Health Nursing Research
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    • v.22 no.3
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    • pp.199-206
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    • 2016
  • Purpose: This study was conducted to monitor the development of Korean premature infant at six-month age and to explore factors related to developmental status of the premature infants. Methods: Participants were 58 premature infants whose corrected age was six-months old and their mothers. The developmental states of infants were followed-up with the Korean Prescreening Developmental Questionnaire (KPDQ-II). Clinical characteristics of the infants were identified from the medical records. Other characteristics including Edinburgh Postnatal Depression Scale, husband's support, social support, and mother-infant attachment were assessed using self-report questionnaires from the mothers. Results: Forty three percent of the infants were in the group of questionable status of development on the KPDQ-II. There were significant differences between the premature infants with normal developmental status and those with questionable developmental status depending on gender ($x^2$=5.03, p=.034), gestational age (t=2.59, p=.012), hospital stay (p=.013), revised Neurobiologic Risk Score (p=.005) and mother-infant attachment score (t=2.12, p=.040). Conclusion: Mother-infant attachment, as well as physiological state of premature infants, is an important variable in early development. Therefore, early monitoring for the development has to be done for physiologically vulnerable premature groups. Also, providing proper nursing support to improve maternal attachment needs to be considered.

An Investigation of the Overseas Project Core Factors of Public New Town Development Company (신도시개발 공기업의 해외시장 진출을 위한 핵심경쟁요소 고찰)

  • Jeon, Ji-Ho;Choi, Seok-Jin;Park, Sang-Hyuk;Han, Seung-Heon;Kim, Hyoung-Kwan
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2007.11a
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    • pp.626-631
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    • 2007
  • New town development project which has manifold operations is usually on a large scale and its spin-off spreads widely. Although international new town development market is widely increasing, new town development market in Korea is now decreasing. Thus, Korean public new town development company which has a lot of business experiences in local new town development market is now facing the necessity of making a foray. This study had a Focus Group Interview with people who experienced in international construction market to set up the core factors of international new town development market. After that, Importance Performance Analysis and Content Analysis were performed with questionnaire to determine the present condition of Korean public new town development company.

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Electrochemical Factors Affecting the Magnetic Properties of Co based Magnetic Nanowires (Co계 자성합금 나노와이어의 특성에 영향을 미치는 전기화학적 변수)

  • Lee, Jong-Wook;Park, Ho-Dong;Lee, Kwan-Hyi;Kim, Gyeung-Ho;Jeung, Won-Young
    • Journal of the Korean Electrochemical Society
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    • v.8 no.3
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    • pp.125-129
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    • 2005
  • We have investigated the electrochemical factors affecting the magnetic properties of hard magnetic CoP nanowires and soft magnetic CoFe nanowires fabricated by ac electrodeposition into self-made AAO(anodic aluminum oxide) nano-templates. AAO template having nano scale pores of high aspect ratio has been prepared through 2-step anodizing of aluminum foil in sulfuric acid. Hard Magnetic properties of CoP nanowires were highly conditional on the applied ac potential which could be a decisive factor to make CoP nanowires made up of either pure hcp crystals or a mixture of hop crystals and fcc crystals. On the contrary to CoFe films, there was no anomalous codeposition in the electrodeposition of soft magnetic CoFe nanowires which exhibited their best saturation magnetization of 238 emu/g at the composition of $Co_{30}Fe_{70}$.

Prognostic Factor Analysis for Management of Chronic Neck Pain : Can We Predict the Severity of Neck Pain with Lateral Cervical Curvature?

  • Seong, Han Yu;Lee, Moon Kyu;Jeon, Sang Ryong;Roh, Sung Woo;Rhim, Seung Chul;Park, Jin Hoon
    • Journal of Korean Neurosurgical Society
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    • v.60 no.4
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    • pp.456-464
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    • 2017
  • Objective : Although little is known about its origins, neck pain may be related to several associated anatomical pathologies. We aimed to characterize the incidence and features of chronic neck pain and analyze the relationship between neck pain severity and its affecting factors. Methods : Between March 2012 and July 2013, we studied 216 patients with chronic neck pain. Initially, combined tramadol (37.5 mg) plus acetaminophen (325 mg) was administered orally twice daily (b.i.d.) to all patients over a 2-week period. After two weeks, patients were evaluated for neck pain during an outpatient clinic visit. If the numeric rating scale of the patient had not decreased to 5 or lower, a cervical medial branch block (MBB) was recommended after double-dosed previous medication trial. We classified all patients into two groups (mild vs. severe neck pain group), based on medication efficacy. Logistic regression tests were used to evaluate the factors associated with neck pain severity. Results : A total of 198 patients were included in the analyses, due to follow-up loss in 18 patients. While medication was successful in reducing pain in 68.2% patients with chronic neck pain, the remaining patients required cervical MBB. Lateral cervical curvature, such as a straight or sigmoid type curve, was found to be significantly associated with the severity of neck pain. Conclusion : We managed chronic neck pain with a simple pharmacological management protocol followed by MBB. We should keep in mind that it may be difficult to manage the patient with straight or sigmoid lateral curvature only with oral medication.

Sleep Onset Insomnia and Depression Discourage Patients from Using Positive Airway Pressure

  • Park, Yun Kyung;Joo, Eun Yeon
    • Journal of Sleep Medicine
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    • v.15 no.2
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    • pp.55-61
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    • 2018
  • Objectives: Despite the accumulating evidence of the effectiveness of positive airway pressure (PAP) therapy in obstructive sleep apnea (OSA) syndrome, adherence to PAP therapy is not high. Several factors reportedly affect PAP adherence; however, it remains unclear whether patients' symptoms were detrimental to adherence rate. This study is aimed at investigating the relationship between insomnia symptoms and adherence. Methods: Retrospective analyses were performed in 359 patients with OSA (mean age $58.4{\pm}13.2$ years; females, n=80). Logistic regression analyses were performed between PAP adherence with clinical factors and questionnaires, such as Epworth Sleepiness Scale, Insomnia Severity Index, and Beck Depression Inventory (BDI). Results: PAP adherence was defined as the use of PAP for ${\geq}4h$ per night on 70% of nights during 30 consecutive days. The median follow-up time was 55 days (interquartile range, 30-119 days), and 54.3% showed poor adherence. Non-adherent patients showed more severe sleep onset insomnia, higher BDI, and higher nadir oxygen saturation ($SaO_2$). Patients with good adherence had higher apnea-hypopnea index, oxygen desaturation index, and respiratory arousal to total arousal ratio. Sleep onset insomnia [odds ratio (OR)=1.792, p=0.012], BDI (OR = 1.055, p=0.026), and nadir $SaO_2$ (OR=1.043, p=0.040) were independently associated with PAP non-adherence. Conclusions: Not the severity of insomnia but sleep onset insomnia was associated with PAP adherence, as well as depressive mood. It suggests that different interventions for reducing insomnia and depressive mood are needed to increase PAP adherence in patients with OSA.

Effect Measurement of Government and Public Service Advertising: Focused on Acceptance Process of Government and Public Service Advertising (정부광고와 공공광고의 효과 측정: 정부·공공광고의 수용과정을 중심으로)

  • Kim, Byoung Hee;Son, Yeong-Gon;Jo, Chang-Hwan;Lee, Hui-Jun
    • (The) Korean Journal of Advertising
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    • v.28 no.6
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    • pp.7-34
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    • 2017
  • The debate surrounding advertising effectiveness is not to be overstated as a major source of advertising research. However, there is still a lack of discussion on the model for measuring the effects of government and public service advertising. This study focuses on this point and develops an index model that can evaluate government advertising. For this purpose, we conducted a survey of 800 respondents in 7 major cities. Based on the creativity evaluation factors (originality, clarity, and appropriateness) of government advertising and the evaluation factors (interest, avoidance, and relevance) of policy contents, a causal model that affects the cognition, attitude, and behavioral responses of the audience was set up. As a result of analysis, originality, clarity, interest, and relevance except for appropriateness and avoidance were meaningful variables for creating government advertising effect such as policy understanding, audience attitude, word of mouth intention of policy. In addition, policy understanding and audience attitude were the main mediating variable influencing the word of mouth intention of policy. Based on research results, this paper discussed the direction for creating effective government and public service advertising in the future.