• Title/Summary/Keyword: Variable Lead Time

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A Study on the Relationship Between Length of Time and Contamination in Open Intravenous Solutions (정맥주사용 수액의 개방후 시간경과에 따른 오염도에 관한 실험연구)

  • 김일원
    • Journal of Korean Academy of Nursing
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    • v.16 no.1
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    • pp.67-80
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    • 1986
  • The use of intravenous solutions for fluid replacement has become an integral part of patient care, This widespread use of intravenous solutions has increased the risk of contamination that can lead to septicemia and phlebitis. The literature regarding contamination of in use intravenous solutions recommends a standard 24-hour time limit on the use of these fluids. But the desings of these studies did not incorporate a time variable related to contamination. In other studies, however, time was a manipulated variable: but data regarding the onset of contamination were conflicting. Because published reports conflict with regard to a time standard related to the use of intravenous therapy, additional empirical data are needed upon which to base the standards of care regulating use of intravenous therapy. This study investigated rate of contamination in simulated in-use intravenous solutions to obtain data from which to recomend a standard time period for the administration of intravenous solutions. In this study samples were drawn from 60 bottles of 5% D/W solution at predetermined time intervals over 48 hours and samples were inoculated to Thio-glychollate Broth. After 10 days' culturing in that Broth, samples were cultured on blood agar plates for 18∼48 hours to determine the rate of contamination. was found at all time Period, regardless of the presence or absence of nurse's gloving in the preparation of fluids, the location in which the experimentations were performed, the contamination level of surrounding air, or the length of time during which solutions were opened. Data from this study support the use of a 48-hour time period on which to base the standard involved in ready-to-use simple intravenous solutions without additives. In emergency departments and critical care areas where intravenous solutions are prepared in advance, the suggested time standard supported by the data generated from this study is 48 hours, not 24 hour. Data from this study support a 24-hour time standard for changing in-use intravenous solutions when the contamination results from the manipulation of intravenous infusion system by hospital personnel, or from some other exogenous sources during administration. Because contamination that does occur within 48 hours in intravenous solutions must be introduced from some exogenous sources, further empirical studies based on the identification of sources of contamination and factors that affect the rate of contamination, are needed to investigate the currently employed standard of intravenous therapy and to provide the patient with more efficient and safer intravenous thereapy.

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MODELING ACCURATE INTEREST IN CASH FLOWS OF CONSTRUCTION PROJECTS TOWARD IMPROVED FORECASTING OF COST OF CAPITAL

  • Gunnar Lucko;Richard C. Thompson, Jr.
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.467-474
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    • 2013
  • Construction contactors must continuously seek to improve their cash flows, which reside at the heart of their financial success. They require careful planning, analysis, and optimization to avoid the risk of bankruptcy, remain profitable, and secure long-term growth. Sources of cash include bank loans and retained earnings, which are conceptually similar in that they both incur a cost of capital. Financial management therefore requires accurate yet customizable modeling capabilities that can quantify all expenses, including said cost of capital. However, currently existing cash flow models in construction engineering and management have strongly simplified the manner in which interest is assessed, which may even lead to overstating it at a disadvantage to contractors. The variable nature of cash balances, especially in the early phases of construction projects, contribute to this challenging issue. This research therefore extends a new cash flow model with an accurate interest calculation. It utilizes singularity functions, so called because of their ability to flexibly model changes across any number of different ranges. The interest function is continuous for activity costs of any duration and allows the realistic case that activities may begin between integer time periods, which are often calendar months. Such fractional interest calculation has hitherto been lacking from the literature. It also provides insights into the self-referential behavior of compound interest for variable cash balances. The contribution of this study is twofold; augmenting the corpus of financial analysis theory with a new interest formula, whose strengths include its generic nature and that it can be evaluated at any fractional value of time, and providing construction managers with a tool to help improve and fine-tune the financial performance of their projects.

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A Simulation Study for Evaluation of Alternative Plans and Making the Upper-limit for Improvement in Productivity of Flow-shop with Considering a Work-wait Time (흐름생산 공정에서의 작업 대기시간을 고려한 공정 개선 상한선 도출 : H사의 공정 개선 계획안 시뮬레이션 사례를 중심으로)

  • Song, Young-Joo;Woo, Jong-Hun;Lee, Don-Kun;Shin, Jong-Gye
    • Journal of the Korea Society for Simulation
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    • v.17 no.2
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    • pp.63-74
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    • 2008
  • The design of best efficient production process is common requirements of the production strategy department and the process planning department to maximize the revenue and accomplish target production volumes in the production periods. And they use several general methods for that-line-balancing, removing of the bottle-neck process, facility ramp-up, increasing of the worker's utilization, etc. But, those methods have depended on analytic, static and arithmetic calculations, yet. So, irregular work-waiting time causing the delay time isn't include in extracting production capacity, especially in the line production process. The work-waiting time is changed irregularly along the variation of each machine and very important for calculate real product lead-time and forecasting target production volumes. At this thesis, i'm going to mention the importance of the delay time of conveyor system which can be extracted by discrete-event simulation. And suggest it as a new main variable that must be considered at designing new production system. Then experimented and tested that's effects in the H-company case, conveyor based line production process.

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Factors Affecting Caregiver Burden in Caregivers of Patients with Parkinson's Disease (파킨슨병 환자 부양자의 부양부담에 영향을 미치는 요인)

  • Kim, Dong Won;Bae, Eun Sook
    • Korean Journal of Adult Nursing
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    • v.27 no.3
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    • pp.283-293
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    • 2015
  • Purpose: Depression is a common sign of suffering among the patients with Parkinson's disease (PD). Frequent and severe neuropsychiatric symptoms lead to high levels of distress in patients and their caregivers, which results in the high levels of caregiver burden. The aim of this study was to determine the predictors of caregiver burden in caregivers of the patients with Parkinson's disease (PD). Methods: The study included 183 consecutive PD patients and their caregivers. Patients were assessed using the Hoehn and Yahr scale, Mini Mental State Examination (MMSE), Beck Depression Inventory (BDI), and Schwab and England Activities of Daily Living Scale. Caregivers' depressive symptoms were evaluated using the Caregiver Burden Inventor (CBI), BDI, and World Health Organization Quality of Life Scale. Results: All of the patients reported one or more neuropsychiatric symptoms. Patients' and caregivers' depressive symptoms, caregivers' age and education, time for caregiving, and quality of life were significantly associated with the increased caregiver burden. After controlling the level of education as a potential confounding variable, depression in both patients and caregivers, time for caregiving, and quality of life explained 45.6% of the variance in caregiver burden. Conclusion: Substantial attention needs to be given to the early identification of depression in PD patients and their caregivers to improve caregivers' quality of life and burden.

A Study about the Relation of Product Environment and Supply Chain Structure (환경과 공급체인 구조와의 관계에 관한 연구)

  • 문성암;곽신영;박성훈
    • Journal of Distribution Research
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    • v.7 no.1
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    • pp.41-59
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    • 2002
  • Analysis about supply chain structure was achieved in product unit that is not 'business' dimension that is existent discussion target in surrounding and supply chain structure as that this study analyzes positively how supply chain structure according to business surroundings of product changes. This can do that analysis of product unit in synthetic supply chain management is essential when recognize the importance that supply chain management must consist by product special quality according to corporation's each product. Sort product environment and studied relation with supply chain structure to achieve study purpose hereupon. Structure variable of supply chain drew through existent literature study here. Executed question investigation for supply chain by product for study that is actual proof enemy, and figure method used analysis of variance (ANOVA) mainly. If summarize result of study, result that analyze relation between business environment of product and supply chain structure, according to business environment of product, showed that supply chain structure changes. Certified that relation of two group (environment group of uncertain product and environment group of stable product) of business environment of product and structure variable (that is number of participant of supply chain, lead time of supply chain, about administration's independence, response points of supply chain) of supply chain is significant relation all from all structure variables except number of participant of supply chain. Variable that express length of supply chain from structure Variable of supply chain is number of participant of supply chain and lead time of supply chain, and variable that display monitoring or trust aspect for supply chain is administration's independence degree and response points of supply chain. As analysis result, product that environment is uncertain is appearing more shortly than product that length of supply chain stabilizes, and also, monitoring or trust aspect for supply chain was proved that is consisting abuzzer than product that stabilize. Therefore, showed that put essential point in administration of 'hierarchy'putting first than 'market' when business environment designs supply chain structure in case of uncertain product, and proved that the other side business environment is focusing in administration way of 'market' putting first in case of stable product.

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Evaluation of Various Real-Time Reverse Transcription Quantitative PCR Assays for Norovirus Detection

  • Yoo, Ju Eun;Lee, Cheonghoon;Park, SungJun;Ko, GwangPyo
    • Journal of Microbiology and Biotechnology
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    • v.27 no.4
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    • pp.816-824
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    • 2017
  • Human noroviruses are widespread and contagious viruses causing nonbacterial gastroenteritis. Real-time reverse transcription quantitative PCR (real-time RT-qPCR) is currently the gold standard for the sensitive and accurate detection of these pathogens and serves as a critical tool in outbreak prevention and control. Different surveillance teams, however, may use different assays, and variability in specimen conditions may lead to disagreement in results. Furthermore, the norovirus genome is highly variable and continuously evolving. These issues necessitate the re-examination of the real-time RT-qPCR's robustness in the context of accurate detection as well as the investigation of practical strategies to enhance assay performance. Four widely referenced real-time RT-qPCR assays (Assays A-D) were simultaneously performed to evaluate characteristics such as PCR efficiency, detection limit, and sensitivity and specificity with RT-PCR, and to assess the most accurate method for detecting norovirus genogroups I and II. Overall, Assay D was evaluated to be the most precise and accurate assay in this study. A ZEN internal quencher, which decreases nonspecific fluorescence during the PCR, was added to Assay D's probe, which further improved the assay performance. This study compared several detection assays for noroviruses, and an improvement strategy based on such comparisons provided useful characterizations of a highly optimized real-time RT-qPCR assay for norovirus detection.

Investigating vibration behavior of smart imperfect functionally graded beam subjected to magnetic-electric fields based on refined shear deformation theory

  • Ebrahimi, Farzad;Jafari, Ali
    • Advances in nano research
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    • v.5 no.4
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    • pp.281-301
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    • 2017
  • In this disquisition, an exact solution method is developed for analyzing the vibration characteristics of magneto-electro-elastic functionally graded (MEE-FG) beams by considering porosity distribution and various boundary conditions via a four-variable shear deformation refined beam theory for the first time. Magneto-electroelastic properties of porous FG beam are supposed to vary through the thickness direction and are modeled via modified power-law rule which is formulated using the concept of even and uneven porosity distributions. Porosities possibly occurring inside functionally graded materials (FGMs) during fabrication because of technical problem that lead to creation micro-voids in FG materials. So, it is necessary to consider the effect of porosities on the vibration behavior of MEE-FG beam in the present study. The governing differential equations and related boundary conditions of porous MEE-FG beam subjected to physical field are derived by Hamilton's principle based on a four-variable tangential-exponential refined theory which avoids the use of shear correction factor. An analytical solution procedure is used to achieve the natural frequencies of porous-FG beam supposed to magneto-electrical field which satisfies various boundary conditions. A parametric study is led to carry out the effects of material graduation exponent, porosity parameter, external magnetic potential, external electric voltage, slenderness ratio and various boundary conditions on dimensionless frequencies of porous MEE-FG beam. It is concluded that these parameters play noticeable roles on the vibration behavior of MEE-FG beam with porosities. Presented numerical results can be applied as benchmarks for future design of MEE-FG structures with porosity phases.

Low-Complexity H.264/AVC Deblocking Filter based on Variable Block Sizes (가변블록 기반 저복잡도 H.264/AVC 디블록킹 필터)

  • Shin, Seung-Ho;Doh, Nam-Keum;Kim, Tae-Yong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.4
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    • pp.41-49
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    • 2008
  • H.264/AVC supports variable block motion compensation, multiple reference images, 1/4-pixel motion vector accuracy, and in-loop deblocking filter, compared with the existing compression technologies. While these coding technologies are major functions of compression rate improvement, they lead to high complexity at the same time. For the H.264 video coding technology to be actually applied on low-end / low-bit rates terminals more extensively, it is essential to improve tile coding speed. Currently the deblocking filter that can improve the moving picture's subjective image quality to a certain degree is used on low-end terminals to a limited extent due to computational complexity. In this paper, a performance improvement method of the deblocking filter that efficiently reduces the blocking artifacts occurred during the compression of low-bit rates digital motion pictures is suggested. In the method proposed in this paper, the image's spatial correlational characteristics are extracted by using the variable block information of motion compensation; the filtering is divided into 4 modes according to the characteristics, and adaptive filtering is executed in the divided regions. The proposed deblocking method reduces the blocking artifacts, prevents excessive blurring effects, and improves the performance about $30{\sim}40%$ compared with the existing method.

Time series Analysis of State-space Model and Multiplication ARIMA Model in Dissolved Oxygen Simulation (용존산소 농도모의시 상태공간모형과 승법 ARIMA모형의 시계열 분석)

  • 이원호;서인석;한양수
    • Journal of environmental and Sanitary engineering
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    • v.15 no.2
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    • pp.65-74
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    • 2000
  • The purpose of this study is to develop the stochastic stream water quality model for the intake station of Chung-Ju city waterworks in the Han river system. This model was based on the theory of Box-Jenkins Multiplicative ARIMA(SARIMA) and the state space model to simulate changes of water qualities. Variable of water qualities included in the model are temperature and dissolved oxygen(DO). The models development were based on the data obtained from Jan. 1990 to Dec. 1997 and followed the typical procedures of the Box-Jenkins method including identification and estimation. The seasonality of DO and temperature data to formulate for the SARIMA model are conspicuous and the period of revolution was twelve months. Both models had seasonality of twelve months and were formulates as SARIMA {TEX}$(2,1,1)(1,1,1)_{12}${/TEX} for DO and temperature. The models were validated by testing normality and independency of the residuals. The prediction ability of SARIMA model and state space model were tested using the data collected from Jan. 1998 to Oct. 1999. There were good agreements between the model predictions and the field measurements. The performance of the SARIMA model and state space model were examined through comparisons between the historical and generated monthly dissolved oxygen series. The result reveal that the state space model lead to the improved accuracy.

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Structural Optimization of a Joined-Wing Using Equivalent Static Loads (등가정하중을 이용한 접합날개의 구조최적설계)

  • Lee Hyun-Ah;Kim Yong-Il;Park Gyung-Jin;Kang Byung-Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.5 s.248
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    • pp.585-594
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    • 2006
  • The joined-wing is a new concept of the airplane wing. The fore-wing and the aft-wing are joined together in a joined-wing. The range and loiter are longer than those of a conventional wing. The joined-wing can lead to increased aerodynamic performance and reduction of the structural weight. In this research, dynamic response optimization of a joined-wing is carried out by using equivalent static loads. Equivalent static loads are made to generate the same displacement field as the one from dynamic loads at each time step of dynamic analysis. The gust loads are considered as critical loading conditions and they dynamically act on the structure of the aircraft. It is difficult to identify the exact gust load profile. Therefore, the dynamic loads are assumed to be (1-cosine) function. Static response optimization is performed for the two cases. One uses the same design variable definition as dynamic response optimization. The other uses the thicknesses of all elements as design variables. The results are compared.