Revenue Optimization of Service Compositions using Conditional Request Retries

2013 ◽  
Vol 10 (2) ◽  
pp. 1-22 ◽  
Author(s):  
Miroslav Živković ◽  
Hans van den Berg

Due to the inherent stochastic nature of services execution environment within service oriented systems, a runtime adaptation of the given composition may be required. The authors investigate a runtime service adaptation mechanism based on conditional retries for orchestrated web services. The conditional retry may be issued while a concrete service within composition is executed. The retry could either invoke the same concrete service or a functionally equivalent web service that implements the same task. The authors use dynamic programming to determine the optimal time instances at which the current request should be terminated before request replication. The calculation takes into account different QoS parameters like services' response-time distributions and cost-related parameters, and the solution optimizes the expected revenue of the composite service provider. The authors illustrate the benefits of their approach by numerical calculations, and discuss the impact of considered QoS parameters to the solution at hand.

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Chao Wang ◽  
Daya Luo

AbstractMetastasis is a complex multistep cascade of cancer cell extravasation and invasion, in which metabolism plays an important role. Recently, a metabolic adaptation mechanism of cancer metastasis has been proposed as an emerging model of the interaction between cancer cells and the host microenvironment, revealing a deep and extensive relationship between cancer metabolism and cancer metastasis. However, research on how the host microenvironment affects cancer metabolism is mostly limited to the impact of the local tumour microenvironment at the primary site. There are few studies on how differences between the primary and secondary microenvironments promote metabolic changes during cancer progression or how secondary microenvironments affect cancer cell metastasis preference. Hence, we discuss how cancer cells adapt to and colonize in the metabolic microenvironments of different metastatic sites to establish a metastatic organotropism phenotype. The mechanism is expected to accelerate the research of cancer metabolism in the secondary microenvironment, and provides theoretical support for the generation of innovative therapeutic targets for clinical metastatic diseases.


2021 ◽  
Vol 13 (7) ◽  
pp. 168781402110346
Author(s):  
Yunyue Zhang ◽  
Zhiyi Sun ◽  
Qianlai Sun ◽  
Yin Wang ◽  
Xiaosong Li ◽  
...  

Due to the fact that intelligent algorithms such as Particle Swarm Optimization (PSO) and Differential Evolution (DE) are susceptible to local optima and the efficiency of solving an optimal solution is low when solving the optimal trajectory, this paper uses the Sequential Quadratic Programming (SQP) algorithm for the optimal trajectory planning of a hydraulic robotic excavator. To achieve high efficiency and stationarity during the operation of the hydraulic robotic excavator, the trade-off between the time and jerk is considered. Cubic splines were used to interpolate in joint space, and the optimal time-jerk trajectory was obtained using the SQP with joint angular velocity, angular acceleration, and jerk as constraints. The optimal angle curves of each joint were obtained, and the optimal time-jerk trajectory planning of the excavator was realized. Experimental results show that the SQP method under the same weight is more efficient in solving the optimal solution and the optimal excavating trajectory is smoother, and each joint can reach the target point with smaller angular velocity, and acceleration change, which avoids the impact of each joint during operation and conserves working time. Finally, the excavator autonomous operation becomes more stable and efficient.


2021 ◽  
pp. 85-94
Author(s):  
Ja.A. Vakhrusheva ◽  
◽  
D.N. Smirnov ◽  
I.S. Makushchenko ◽  
◽  
...  

The work carried out studies of the physicomechanical properties of polysulfide sealants of brands of U-30M and UT-31 after thermal, light aging, and the assessment of mushrooms. The data on the resistance of sealants of brands U-30M and UT-31 are investigated and summarized after the impact of accelerated climatic tests and aggressive environments. The optimal time and conditions for the storage of vulcanized sealants in the unattended state and components of sealants in warehouse conditions are determined, as well as the causes of different storage of sealing pastes based on liquid thiocola.


Author(s):  
V.A. Logvin ◽  
◽  
S.A. Sheptunov ◽  

The conditions for the hardening of tools in accordance with the author’s technological routes in the optimal time interval are considered using the functional dependence of the serviceability of plasma generators. This dependence takes into account the workability of the technical devices involved in processing the laying batch of tools in the speci ed time interval. The probability of performing the production process in the estimated time is represented by the product of the trouble-free operation of each glow discharge plasma generator involved in the nishing processing of tools that require a different type of plasma exposure in a certain sequence and duration.


2018 ◽  
Vol 48 (4) ◽  
pp. 559-578 ◽  
Author(s):  
Ritu Tayal ◽  
Rajesh Kumar Upadhya ◽  
Mohit Yadav ◽  
Santosh Rangnekar ◽  
Reena Singh

Purpose The purpose of this study is to empirically examine the association between transformational leadership and employee acceptance to change while establishing the mediating effects of innovative behaviour and the moderating effect of the use of information technology (IT) on this association. Design/methodology/approach In total, 378 employees of ten banks from Uttarakhand, India, participated in a questionnaire-based survey. The proposed hypotheses and the proposed conceptual model were tested using macro process (Hayes, 2013). Findings The results indicated that there exists a positive association between transformational leadership and employee acceptance to change. Furthermore, it was found that this association was mediated by employee innovative behaviour and moderated by the use of IT. Practical implications The findings of this study will help managers to comprehend the significance of the innovative behaviour of employees in moulding their acceptance towards change. This paper should encourage bank managers to perceive the significance of the working practice and the infusion of IT. Furthermore, this study accentuates the significance of an effective leadership style, i.e. transformational leadership, as an essential phenomenon to positively impinge on employee acceptance to change in a service-oriented industry, namely banking. Originality/value The present study enriches the extant research on transformational leadership and employee acceptance to change by demonstrating the use of IT and innovative behaviour as vital and the important factors that influence the level of persuasion that transformational leadership has on employee acceptance to change.


2021 ◽  
Author(s):  
Xu Tian ◽  
Yan-Fei Jin ◽  
Zhao-Li Zhang ◽  
Hui Chen ◽  
Wei-Qing Chen ◽  
...  

Abstract Background: Enteral immunonutrition (EIN) has been extensively applied in cancer patients, however its role in esophageal cancer (EC) patients receiving esophagectomy remains unclear. We performed this network meta-analysis to investigate the impact of EIN on patients undergoing surgery for EC and further determine the optimal time of applying EIN.Methods: We searched PubMed, EMBASE, Cochrane library, and China National Knowledgement Infrastructure (CNKI) to identify eligible studies. Categorical data was expressed as the odds ratio with 95% confidence interval (CI), and continuous data was expressed as mean difference (MD) with 95% CI. Pair-wise and network meta-analysis was performed to evaluate the impact of EIN on clinical outcomes using RevMan 5.3 and ADDIS V.1.16.8 softwares. The surface under the cumulative ranking curve (SUCRA) was calculated to rank all nutritional regimes.Results: Total 14 studies involving 1071 patients were included. Pair-wise meta-analysis indicated no difference between EIN regardless of the application time and standard EN (SEN), however subgroup analyses found that postoperative EIN was associated with decreased incidence of total infectious complications (OR=0.47; 95%CI=0.26 to 0.84; p=0.01) and pneumonia (OR=0.47; 95%CI=0.25 to 0.90; p=0.02) and shortened LOH (MD=-1.01; 95%CI=-1.44 to -0.57; p<0.001) compared to SEN, which were all supported by network meta-analyses. Ranking probability analysis further indicated that postoperative EIN has the highest probability of being the optimal option in terms of these three outcomes.Conclusions: Postoperative EIN should be preferentially utilized in EC patients undergoing esophagectomy because it has optimal potential of decreasing the risk of total infectious complications and pneumonia and shortening LOH.OSF registration number: 10.17605/OSF.IO/KJ9UY.


2020 ◽  
Vol 51 (5) ◽  
pp. 341-353
Author(s):  
David L. Dickinson ◽  
Andrew R. Smith ◽  
Robert McClelland

Abstract. Many people suffer from insufficient sleep and the adverse effects of sleep deprivation are well documented. Research has shown that people’s judgments can be affected by circadian timing. Across three studies, we examined the impact of time-of-day on people’s judgments about hypothetical legal scenarios, hypothesizing that participants responding at a suboptimal time of day (3–5 a.m.) would give higher guilt ratings and be less sensitive to case information (e.g., evidence strength) than participants responding at a more optimal time of day (2–4 p.m.). Although the time-of-day manipulation influenced participants’ self-reported alertness levels, time-of-day did not affect guilt judgments or sensitivity to case information. This research adds to the literature on how extraneous factors may and may not impact probability assessments.


2021 ◽  
Author(s):  
Zahra A. Padhani ◽  
Rehana A. Salam ◽  
Zohra S. Lassi ◽  
Faareha Siddiqui ◽  
Emily C. Keats ◽  
...  

Abstract Background: The complementary feeding (CF) period accompanies a critical window of vulnerability. During this time, failure to consume adequate energy, protein, vitamins and minerals is a significant concern and can lead to poor growth outcomes, increased susceptibility to infections, allergies, and diseases, and lower developmental potential. It is therefore of utmost importance to determine the most optimal time to start CF. The objective of this review is to assess the impact of early and late of introduction of CF on infant health, nutrition and developmental outcomes.Methods: We will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We will search MEDLINE, Embase, CINAHL, CENTRAL, Web of Science, and other databases and key organizational websites using terms related to complementary feeding and infants. We will also search clinicaltrials.gov for ongoing trials. We will include experimental (randomized trials (individually or cluster) and quasi-randomized trials) and observational studies with a concurrent comparison group (cohort (prospective and retrospective), controlled before-after studies and nested case control studies). We will only include studies that enroll infants, living in low, middle- or high-income countries. Outcomes will be assessed for the following two comparisons:1. Early introduction of CF (before 5 months of age) compared to introduction at 5 to 6.9 months of age2. Late introduction of CF (after 7 months) compared to introduction at 5 to 6.9 months of age All the included studies will be screened on Covidence software and analyzed on Review Manager (version 5.4.1) software.Discussion: There are inconsistencies in the existing recommendations for the introduction of CF, as the recommended age for introducing CF ranges between four and six months of age in various international guidelines. It is imperative to evaluate of consequences of both early and late introduction of complementary foods since optimal timing of introduction may have potential beneficial short- and long-term health effects. Systematic review registration: PROSPERO CRD42020218517


PLoS Biology ◽  
2021 ◽  
Vol 19 (4) ◽  
pp. e3001211
Author(s):  
Seyed M. Moghadas ◽  
Thomas N. Vilches ◽  
Kevin Zhang ◽  
Shokoofeh Nourbakhsh ◽  
Pratha Sah ◽  
...  

Two of the Coronavirus Disease 2019 (COVID-19) vaccines currently approved in the United States require 2 doses, administered 3 to 4 weeks apart. Constraints in vaccine supply and distribution capacity, together with a deadly wave of COVID-19 from November 2020 to January 2021 and the emergence of highly contagious Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants, sparked a policy debate on whether to vaccinate more individuals with the first dose of available vaccines and delay the second dose or to continue with the recommended 2-dose series as tested in clinical trials. We developed an agent-based model of COVID-19 transmission to compare the impact of these 2 vaccination strategies, while varying the temporal waning of vaccine efficacy following the first dose and the level of preexisting immunity in the population. Our results show that for Moderna vaccines, a delay of at least 9 weeks could maximize vaccination program effectiveness and avert at least an additional 17.3 (95% credible interval [CrI]: 7.8–29.7) infections, 0.69 (95% CrI: 0.52–0.97) hospitalizations, and 0.34 (95% CrI: 0.25–0.44) deaths per 10,000 population compared to the recommended 4-week interval between the 2 doses. Pfizer-BioNTech vaccines also averted an additional 0.60 (95% CrI: 0.37–0.89) hospitalizations and 0.32 (95% CrI: 0.23–0.45) deaths per 10,000 population in a 9-week delayed second dose (DSD) strategy compared to the 3-week recommended schedule between doses. However, there was no clear advantage of delaying the second dose with Pfizer-BioNTech vaccines in reducing infections, unless the efficacy of the first dose did not wane over time. Our findings underscore the importance of quantifying the characteristics and durability of vaccine-induced protection after the first dose in order to determine the optimal time interval between the 2 doses.


Blood ◽  
2017 ◽  
Vol 129 (5) ◽  
pp. 547-552 ◽  
Author(s):  
Patrick Auberger ◽  
Alexandre Puissant

AbstractAutophagy is a lysosomal pathway involved in degradation of intracellular material. It appears as an adaptation mechanism that is essential for cellular homeostasis in response to various stress conditions. Over the past decade, many studies have linked alteration of autophagy with cancer initiation and progression, autoimmune, inflammatory, metabolic, and degenerative diseases. This review highlights recent findings on the impact of autophagy on leukemic transformation of normal hematopoietic stem cells and summarizes its role on leukemic cell response to chemotherapy.


Sign in / Sign up

Export Citation Format

Share Document