• Title/Summary/Keyword: Total uncertainty

Search Result 490, Processing Time 0.03 seconds

Cost Effectiveness Analysis of Different Management Strategies between Best Supportive Care and Second-line Chemotherapy for Platinum-resistant or Refractory Ovarian Cancer

  • Luealon, Phanida;Khempech, Nipon;Vasuratna, Apichai;Hanvoravongchai, Piya;Havanond, Piyalamporn
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.2
    • /
    • pp.799-805
    • /
    • 2016
  • Background: There is no standard treatment for patients with platinum-resistant or refractory epithelial ovarian cancer. Single agent chemotherapies have evidence of more efficacy and less toxicity than combination therapy. Most are very expensive, with appreciable toxicity and minimal survival. Since it is difficult to make comparison between outcomes, economic analysis of single-agent chemotherapy regimens and best supportive care may help to make decisions about an appropriate management for the affected patients. Objective: To evaluate the cost effectiveness of second-line chemotherapy compared with best supportive care for patients with platinum-resistant or refractory epithelial ovarian cancer. Materials and Methods: A Markov model was used to estimate the effectiveness and total costs associated with treatments. The hypothetical patient population comprised women aged 55 with platinum-resistant or refractory epithelial ovarian cancer. Four types of alternative treatment options were evaluated: 1) gemcitabine followed by BSC; 2) pegylated liposomal doxorubicin (PLD) followed by BSC; 3) gemcitabine followed by topotecan; and 4) PLD followed by topotecan. Baseline comparator of alternative treatments was BSC. Time horizon of the analysis was 2 years. Health care provider perspective and 3% discount rate were used to determine the costs of medical treatment in this study. Quality-adjusted life-years (QALY) were used to measure the treatment effectiveness. Treatment effectiveness data were derived from the literature. Costs were calculated from unit cost treatment of epithelial ovarian cancer patients at various stages of disease in King Chulalongkorn Memorial Hospital (KCMH) in the year 2011. Parameter uncertainty was tested in probabilistic sensitivity analysis by using Monte Carlo simulation. One-way sensitivity analysis was used to explore each variable's impact on the uncertainty of the results. Results: Approximated life expectancy of best supportive care was 0.182 years and its total cost was 26,862 Baht. All four alternative treatments increased life expectancy. Life expectancy of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 0.510, 0.513, 0.566, and 0.570 years, respectively. The total cost of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 113,000, 124,302, 139,788 and 151,135 Baht, respectively. PLD followed by topotecan had the highest expected quality-adjusted life-years but was the most expensive of all the above strategies. The incremental cost-effectiveness ratios (ICER) of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 344,643, 385,322, 385,856, and 420,299 Baht, respectively. Conclusions: All of the second-line chemotherapy strategies showed certain benefits due to an increased life-year gained compared with best supportive care. Moreover, gemcitabine as second-line chemotherapy followed by best supportive care in progressive disease case was likely to be more effective strategy with less cost from health care provider perspective. Gemcitabine was the most cost-effective treatment among all four alternative treatments. ICER is only an economic factor. Treatment decisions should be based on the patient benefit.

Development of Estimation Methods of Pollutant Emissions from Railroad Diesel Rolling Stocks (철도디젤차량에서 배출되는 오염물질의 배출량 산정방법 개발)

  • 박덕신;김동술
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.20 no.4
    • /
    • pp.539-553
    • /
    • 2004
  • Up to the present time, many methods to estimate emissions from a particular diesel engines have wholly depended on the quantity of diesel fuel consumed. Then, the recommended emission factors were normalized by fuel consumption, and further total activity was estimated by the total fuel consumed. One of main purposes in the study is newly to develop emission factors for the railroad diesel rolling stock (RDRS) and to estimate a total amount of major gaseous pollutants from the RDRS in Korea. Prior to develop a Korean mode emission factor. the emission factor from the USEPA was simply applied for comparative studies. When applying the USEPA emission factors, total exhaust emissions from the RDRS in Korea were estimated by 28,117tons of NOx, 2,832.3tons of CO, and 1,237.5tons of HC, etc in 2001. In this study, a emission factor for the RDRS, so called the KoRail mode (the Korean Railroad mode) has been developed on the basis of analyzing the driving pattern of the Gyeongbu-Line especially for the line-haul mode. Explicitly to make the site specific emission factors, many uncertainty problems concerning weighting factors for each power mode, limited emission test, incomplete data for RDRS, and other important input parameters were extensively examined. Total exhaust emissions by KoRail mode in Korea were estimated by 10,960tons of NOx, and 4,622tons of CO, and so on in the year of 2001. The emissions estimated by the USEPA mode were 2.6 times higher for NOx, and 1.6 times lower for CO than those by the KoRail mode. As a conclusion, based on the emission calculated from both the USEPA mode and the KoRail mode, the RDRS is considered as one of the significant mobile sources for major gaseous pollutants and thus management plans an(1 control strategies for the RDRS must be established to improve air quality near future in Korea.

Stochastic Probability Model for Preventive Management of Armor Units of Rubble-Mound Breakwaters (경사제 피복재의 유지관리를 위한 추계학적 확률모형)

  • Lee, Cheol-Eung;Kim, Sang Ug
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.33 no.3
    • /
    • pp.1007-1015
    • /
    • 2013
  • A stochastic probability model based on the non-homogeneous Poisson process is represented that can correctly analyze the time-dependent linear and nonlinear behaviors of total damage over the occurrence process of loads. Introducing several types of damage intensity functions, the probability of failure and the total damage with respect to mean time to failure has been investigated in detail. Taking particularly the limit state to be the random variables followed with a distribution function, the uncertainty of that would be taken into consideration in this paper. In addition, the stochastic probability model has been straightforwardly applied to the rubble-mound breakwaters with the definition of damage level about the erosion of armor units. The probability of failure and the nonlinear total damage with respect to mean time to failure has been analyzed with the damage intensity functions for armor units estimated by fitting the expected total damage to the experimental datum. Based on the present results from the stochastic probability model, the preventive management for the armor units of the rubble-mound breakwaters would be suggested to make a decision on the repairing time and the minimum amounts repaired quantitatively.

MEANING OF 'EXHAUSTED ECLIPSES' IN ANCIENT EPHEMERIDES (고대 역법에 나오는 일식기(日食旣)의 의미)

  • Ahn, Sang-Hyeon
    • Publications of The Korean Astronomical Society
    • /
    • v.23 no.2
    • /
    • pp.65-71
    • /
    • 2008
  • It has been considered that 'exhausted eclipses' (日食旣) were total eclipses. However, modern precise calculations show that a significant fraction of such records are not realized to be total. Thus we doubt that the two concepts are equivalent. Here we investigate the meaning of 'exhausted eclipses' in the east-Asian history. We first find that eclipses of magnitude greater than 0.8 were regarded as 'exhausted eclipses' by a Korean astronomer of the 18th-century Choson dynasty. His notion was based upon the definition of 'exhausted eclipses' in the ephemerides of pre-modern Chinese dynasties. According to those ephemerides, the 'exhausted eclipses', whose magnitude is greater than 0.8, have the first contact at the western part of the solar disk and the fourth contact at the eastern part of the solar disk. A simple geometrical calculation shows that such cases really occur when the magnitude of eclipse is greater than 0.7. We pointed out that such an ancient definition might not be impractical for ancient astronomers, because the uncertainty of eclipse magnitude estimated by ancient Chinese ephemerides was 10% and the human sight has a spatial resolution of 1.2 arcmin, which is approximately one twentieth of the Sun's angular diameter.

A Computerized Construction Cost Estimating Method based on the Actual Cost Data (실적 공사비에 의한 예정공사비 산정 전산화 방안)

  • Chun Jae-Youl;Cho Jae-ho;Park Sang-Jun
    • Korean Journal of Construction Engineering and Management
    • /
    • v.2 no.2 s.6
    • /
    • pp.90-97
    • /
    • 2001
  • The paper considers non-deterministic methods of analysing the risk exposure in a cost estimate. The method(referred to as the 'Monte Carlo simulation' method) interprets cost data indirectly, to generate a probability distribution for total costs from the deficient elemental experience cost distribution. The Monte Carlo method is popular method for incorporating uncertainty relative to parameter values in risk assessment modelling. Non-deterministic methods, they are here presented as possibly effective foundation on which to risk management in cost estimating. The objectives of this research is to develop a computerized algorithms to forecast the probabilistic total construction cost and the elemental work cost at the planning stage.

  • PDF

Development of the Control System for the Motor-Driven Electromechanical Total Artificial Hearta

  • Kim, Hee-Chan;Lee, Sang-Hun;Kim, Jong-Won-;Kim, Jin-Tae-;Min, Byoung-Goo
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1988.10b
    • /
    • pp.858-863
    • /
    • 1988
  • A micro-processor based control system for a brushless DC motor used in the motor-driven electromechanical total artificial heart was developed. Functionally, the control system is composed of two parts. The first part is the velocity and position controller to assure that the motor follows a predetermined optimal velocity profile with minimal energy consumption, and to guarantee the full stroke length. This part also utilize the passive adaptive control method to be robust against the load disturbance, system parameter variation, and uncertainty which is the environment of artificial heart system. The pump output control is the second part, and this part provides the required responses of the artificial heart to the time-varying physiologic demands. The basic requirements of these responses are preload sensitivity, afterload insensitivity, and the balanced ventricular outputs. The performance and reliability of this control system was evaluated through a series of mock circulation tests and animal implantation, and the results are very encouraging.

  • PDF

Nonlinear Interferometry for Measuring the Nonresonant Third Order Susceptibilities of Gases (비선형분광간섭을 이용한 여러가지 기체의 비공명 3차 감수율 측정)

  • 한재원;이은성
    • Korean Journal of Optics and Photonics
    • /
    • v.5 no.4
    • /
    • pp.473-480
    • /
    • 1994
  • We have applied nonlinear interferometry of coherent anti-Stokes Raman spectroscopy (CARS) to measure the nonresonant third order susceptibilities of various gases. For the experiment, we placed two gas cells serially and filled the first cell with argon as a calibration standard and the second cell with gases under test. The interference fringes of the CARS signals generated in the two gas cells were obtained by changing the thickness of the phase shifting unit which was made of BK-7 glass. The total effective nonresonant susceptibilities were determined from the measured amplitudes of the interference fringes of the CARS signals of the gases. The nonresonant susceptibilities were obtained by subtracting off resonant vibrational contributions from the total effective susceptibilities. The results of this work are compared with the published data and the overall uncertainty is estimated to be less than 5%. an 5%.

  • PDF

Fair Power Control Using Game Theory with Pricing Scheme in Cognitive Radio Networks

  • Xie, Xianzhong;Yang, Helin;Vasilakos, Athanasios V.;He, Lu
    • Journal of Communications and Networks
    • /
    • v.16 no.2
    • /
    • pp.183-192
    • /
    • 2014
  • This paper proposes a payment-based power control scheme using non-cooperative game with a novel pricing function in cognitive radio networks (CRNs). The proposed algorithm considers the fairness of power control among second users (SUs) where the value of per SU' signal to noise ratio (SINR) or distance between SU and SU station is used as reference for punishment price setting. Due to the effect of uncertainty fading environment, the system is unable to get the link gain coefficient to control SUs' transmission power accurately, so the quality of service (QoS) requirements of SUs may not be guaranteed, and the existence of Nash equilibrium (NE) is not ensured. Therefore, an alternative iterative scheme with sliding model is presented for the non-cooperative power control game algorithm. Simulation results show that the pricing policy using SUs' SINR as price punishment reference can improve total throughput, ensure fairness and reduce total transmission power in CRNs.

Related Loan on Real Estate Firm Performance in an Emerging Market

  • PURWANTO, Purwanto
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.7 no.10
    • /
    • pp.697-706
    • /
    • 2020
  • This study investigates the relationship between related loan, ownership concentration and real estate firm performance. The data was collected from 35 real estate firms listed on Indonesia Stock Exchange from 2007 to 2012. Related loans are viewed from the angle of related lending and loan. Related lending and loan is measured by the related lending on total lending ratio and related loan on total loan ratio. Firm performance is measured by the asset turnover ratio and return on assets ratio. Ownership concentration is measured by the right cash flow. The data analysis was done with regression analysis and panel data. The results of the study found that related loans had a positive effect on sales but had no effect on profits. This supports the efficient transaction hypothesis. On the other hand, related lending has a positive effect on profits that supports opportunistic transactions. Ownership concentration moderates the effect of related loan on company's performance. The related lending are beneficial for mutually supporting activities in the real estate sector business group in Indonesia, but related loans have the potential to be used in tunneling activities. The paper contributes to the related party transaction in benefits-risks of related lending and related loan in uncertainty context.

The Simultaneous Measurement of Vibration and Applied forces at a Power tool handle for the Evaluation of Hand-transmitted Vibration (수전달 진동 평가를 위한 공구 핸들에서의 진동과 작용력의 동시 측정)

  • Choi, Seok-Hyun;Jang, Han-Kee;Park, Tae-Won
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2004.11a
    • /
    • pp.689-694
    • /
    • 2004
  • To increase accurateness and reliability of the evaluation of power tool vibration transmitted to an operator, it is necessary to measure grip and feed forces during the measurement of hand-transmitted vibration. In the study a system was invented to measure the vibration and the grip and/or feed force, which consists of a measurement handle and a PC with data acquisition system and the software. Strain gauges and an accelerometer were mounted on the handle for the simultaneous measurement of the forces and the vibration. The program in the system makes it possible to monitor the grip and feed force during the tool operation so that the operator keeps the applying forces within the pre-determined range. Investigating the vibration total values, frequency-weighted root mean square accelerations at the handle, obtained at various conditions with control of the grip and feed force showed more consistency than those measured without force control. By using the system the experimenter can reduce uncertainty of the measured vibration.

  • PDF