• Title/Summary/Keyword: attrition rate

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A Study on the Reactivity of Zinc-based Sorbents Using Yellow Earth as Support at Middle Temperatures (황토를 지지체로 사용한 중온건식 아연계 탈황제의 반응특성 연구)

  • 박노국;정용화;이종대;류시옥;이태진
    • Journal of Energy Engineering
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    • v.12 no.4
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    • pp.302-308
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    • 2003
  • The peformence tests of zinc-based desulfurization sorbents using the yellow earth as support for the hot gas clean up were carried out. The zinc-based sorbent with 25 wt% yellow earth was prepared, and their properties such as the reaction rate, the sulfur capacity and the attrition resistance, were investigated. The reactivity tests for hot gas desulfurization was performed at middle temperatures (sulfidation/regeneration:480$^{\circ}C$/580$^{\circ}C$). During multi-cyclic desulfurization, the deactivation of zinc-based sorbent was decreased by the addition of yellow earth, and their efficiency was enhanced. The ZnO/yellow earth sorbent had high reactivity, good regenerability, long-term durability (about 19 gS/100 g sorbent for 10-cycles) and high attrition resistance (AI=19.1%). It was concluded that the peroperties of zinc-based sorbent were improved by metal oxides (Fe$_2$O$_3$, Na$_2$O, MnO$_2$, etc) in the yellow earth. From these results, it was confirmed that the desulfurization properties of zinc-based sorbents at middle temperatures could be improved by the yellow earth using as support.

Barriers to Participation in a Randomized Controlled Trial of Qigong Exercises Amongst Cancer Survivors: Lessons Learnt

  • Loh, Siew Yim;Lee, Shing Yee;Quek, Kia Fatt;Murray, Liam
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.12
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    • pp.6337-6342
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    • 2012
  • Background: Clinical trials on cancer subjects have one of the highest dropout rates. Barriers to recruitment range from patient-related, through institutional-related to staff-related factors. This paper highlights the low response rate and the recruitment barriers faced in our Qigong exercises trial. Materials and Method: The Qigong trial is a three-arm trial with a priori power size of 114 patients for 80% power. The University Malaya Medical Centre database showed a total of 1,933 patients from 2006-2010 and 751 patients met our inclusion criteria. These patients were approached via telephone interview. 131 out of 197 patients attended the trial and the final response rate was 48% (n=95/197). Results: Multiple barriers were identified, and were regrouped as patient-related, clinician-related and/or institutional related. A major consistent barrier was logistic difficulty related to transportation and car parking at the Medical Centre. Conclusions: All clinical trials must pay considerable attention to the recruitment process and it should even be piloted to identify potential barriers and facilitators to reduce attrition rate in trials.

A study on the characteristic of grinding by spark-out (불꽃소멸에 의한 연삭특성에 관한 연구)

  • 이연종;김정두
    • Journal of the korean Society of Automotive Engineers
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    • v.15 no.3
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    • pp.120-125
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    • 1993
  • The surface roughness of workpiece is reduced during spark-out. The reduction of roughness is a benefit of spark-out, but spark-out lowers productivity. The characteristics of spark-out are different to those of plunge grinding to which feed is applied. This difference is due to overlapping cutting during spark-out. Effect of spark-out is in proportion to volume of grain wear. This phenomenon is due to different overlapping area. Dressing interval can be enlarged by spark-out, when volume of grain wear is large. In this study, the characteristic of spark-out was studied by spark-out obserbation in various grinding conditions. For this purpose thrust force, spark-out time and surface roughness of workpiece were experimentally investigated in various grinding conditions.

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A Study on the Development of a Lanchester-Type Model Incorporating Firing & Observing States in the Direct Fire Engagement (Firing State와 Observing State를 갖는 Lanchester형 전투모형에 관한 연구)

  • Ham Il-Hwan;Choe Sang-Yeong;Song Mun-Ho
    • Journal of the military operations research society of Korea
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    • v.17 no.2
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    • pp.44-53
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    • 1991
  • This paper is aimed to develop a Lanchester type combat model for the direct-fire engagement. This model incorporates number of combatants, inter-firing time, detection time by movement, detection probability by the signature of fire, where the inter-firing time and the detection time are assumed to follow a negative exponential distribution. The approach to modeling is as follows : in the process of an engagement, a combatant takes one of the states('observing' state or 'firing' state), a combatant is initially in the observing state, if the combatant detects a target, he changes his state from 'observing' to 'firing' and will cause attrition to the opposing forces. Thus this transition mechanism is embodied into the differential equation form with each transition rate. A limited examination of the validity has been conducted by comparison with the Monte-Carlo simulation model 'BAGSIM', and with a traditional Deterministic Lanchester model.

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EFFECTIVE USAGE OF FIXED AMOUNT OF SCATTERABLE MINES ON THE INFANTRY BATTLEFIELD

  • Lee, Jae-Yeong
    • Journal of the military operations research society of Korea
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    • v.16 no.1
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    • pp.94-112
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    • 1990
  • The basic mathematical tools are developed to determine the optimum emplacement of limited numbers of scatterable mines on the infantry battlefield. A deterministic model is developed for heterogeneous infantry battalion level battle using APL version 7.0. The Helmbold-type combat equation is applied to claculate comparative casulties, and range dependency is also considered to establish the correlation between attrition rate coefficients and the distance of opposing forces, Based on this deterministic model the effective range for employment of scatterable mines is determined. Because mines are primarily effective when employed in conjunction with direct fire weapons, it is inferred that minefield are best employed when used within the maximum effective range of infantry weapons systems such as the M16Al rifle. The model developed verifies this fact.

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An Inclusive Method for Application of Combat Termination Rules (전투종료규칙의 포괄적 적용방법)

  • 백자성;하석태
    • Journal of the military operations research society of Korea
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    • v.26 no.1
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    • pp.125-144
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    • 2000
  • Occasionally, there are combat situations which one or both forces can´t terminate the combat using selected combat termination rule according to given relationship between ratio of attrition rate coefficient and threshold values. In this study, we classify the situations that one or both forces can´t terminate the combat with selected combat termination rule into four conditions. Condition${\circled1}$ is the situation which both Blue and Red can terminate the combat using all selected combat termination rules. condition${\circled2}$ and condition${\circled3}$ are those which neither Blue or Red can terminate the combat using selected proportional decision rule, and condition${\circled4}$ is that which both Blue and Red can´t terminate the combat using selected proportional decision rule. We analyze the effect of combat termination rules on parity number, final combat power, and combat durations for each conditions. Also, we propose the method to apply the analyzed effect of combat termination rules to combat analysis.

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Attrition Effect of Beads on Enzymatic Saccharification of Raw Starch (생전분의 효소당화에서 유리구 마찰효과)

  • Choi, Seong-Hyun;Kim, Chan-Jo;Lee, Seuk-Keun
    • Applied Biological Chemistry
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    • v.32 no.4
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    • pp.374-377
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    • 1989
  • To optimize the enzymatic saccharification of raw-starch, reaction conditions by shaking with glass beads were adapted together with ${\alpha}-amylase$ from Streptomyces sp. 4M-2 and amyloglucosidase from commercial source. When raw-starch was degraded by the ${\alpha}-amylase$ in shaking flask with beads (raw-starch : bead in diam. of 3mm=1 : 5 by weight) at the shaker speed of 300rpm, the saccharification rate of corn and potato starch were increased up to 88% and 69% after 30 hrs of reaction, respectively. Application of the amyloglucosidase in combination with the ${\alpha}-amylase$ enhanced the rate of saccharifcation: 88% of saccharification was obtained in 6 hrs for raw-corn starch under the same reaction conditions as above.

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Statistical review and explanation for Lanchester model (란체스터 모형에 대한 통계적 고찰과 해석)

  • Yoo, Byung Joo
    • The Korean Journal of Applied Statistics
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    • v.33 no.3
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    • pp.335-345
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    • 2020
  • This paper deals with the problem of estimating the log-transformed linear regression model to fit actual battle data from the Ardennes Campaign of World War II into the Lanchester model. The problem of determining a global solution for parameters and multicollinearity problems are identified and modified by examining the results of previous studies on data. The least squares method requires attention because a local solution can be found rather than a global solution if considering a specific constraint or a limited candidate group. The method of exploring this multicollinearity problem can be confirmed by a statistic known as a variance inflation factor. Therefore, the Lanchester model is simplified to avoid these problems, and the combat power attrition rate model was proposed which is statistically significant and easy to explain. When fitting the model, the dependence problem between the data has occurred due to autocorrelation. Matters that might be underestimated or overestimated were resolved by the Cochrane-Orcutt method as well as guaranteeing independence and normality.

Quitline Activity in Rajasthan, India

  • Gupta, Rakesh;Verma, Vinit;Mathur, Pankaj
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.sup2
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    • pp.19-24
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    • 2016
  • Quitline activity in Rajasthan, India is a voluntary activity of Rajasthan Cancer Foundation (RCF) since April 2013. To kick-off, it took the benefit of the State Government- PIRAMAL SWASTHYA (PS)1 collaborative 104 Health Information Helpline that existed already in public-private partnership. It is a reactive quitline that helps callers through the counselors and nursing staff trained specifically through the weekly sessions held by the first author, the RCF resource on quitline. Besides structuring of the scripts for primary intervention and follow-ups after 1 week, 1 month, 6 months and a year, he also monitors calls, advices and coordinates with the supervisors to manage and analyze the data base, and reports to the PS lead at the Jaipur Center on overall performance and to plan strategic communication with the State Government on its outcomes. The quitline has limitations of its informal existence through a voluntary effort of RCF, no specific resource allocation, suboptimal data management, minimal awareness in the masses due to poor IEC (Information, Education and Communication; except its efforts made by RCF in last 1 year through the government-run State TV and City Radio) and staff shortage and its attrition due to lack of plan for career advancement. Despite these challenges in the year 2013, the quit line has registered a quit rate (for complete abstinence) of 19.93% amongst 1525 callers. The quit rate were 58.01% (304/ 524) among the responders at the 3rd follow-up at 18 months (in September 2014)2. In view of an increase in quit rate by 5- 9 times over the prevailing quit rate in the former ever daily users [both smokers and the users of smokeless tobacco (SLT)], efforts are being made by RCF in concurrence with PS to have this cost-effective model established formally with optimal resource allocation in collaboration with willing agencies (the State and Central Governments and the International Quitline Agencies) and its replication in 4 more states where PS is collaborating with the respective state governments similarly (Assam, Chhattisgarh, Jharkhand and Karnataka).

Using Analytic Network Process to Construct Evaluation Indicators of Knowledge Sharing Effectiveness in Taiwan's High-tech Industries

  • Liu, Pang-Lo;Tsai, Chih-Hung
    • International Journal of Quality Innovation
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    • v.9 no.2
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    • pp.99-117
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    • 2008
  • High-tech industry has been the principal economic source for Taiwan in recent years. The characteristics of high-tech industries in Taiwan are changeable product markets, short product life cycles and high company attrition rate. In the globalization trend, the high-tech industry has gradually increased corporate competitiveness and reached the goal of sustainable operations through knowledge management, knowledge sharing and new product research and development. Firms have aggressively strengthened and integrated their internal and external resources and enhanced knowledge sharing to increase industry operational performance. Effectively strengthening the knowledge management operation and performance evaluation of knowledge sharing in Taiwan's high-tech industry has become a critical issue. In the selection of knowledge sharing Key Performance Indicators (KPI), this research divided the knowledge sharing indicators into representative strategic indicators such as organizational knowledge learning, organizational knowledge resources, organizational information capacity and organizational knowledge performance through screening using Factor Analysis. The characteristics of the constructs were interdependent. This research calculated and adjusted the correlation among the key performance knowledge sharing indicators using ANP and determined the relative weight of knowledge sharing.