scholarly journals Queuing system in E- Commerce

This paper explores an investigation on Queuing framework in E-trade. Online business (electronic trade) is the acquiring and selling of product and adventures, or the transmitting of benefits or data, over an electronic system, basically the web. It is the trading of things or administrations using PC systems like Internet or online casual networks. Here the Business is led utilizing PCs, phones, fax machines, standardized tag per users, Visas, ATM or other electronic apparatuses without the trading of paper-based records or physically moving to a strip mall. It incorporates exercises, for instance, acquirement, request passage, trade handling, online installment, verification, stock control, request satisfaction, shipment, and client support. In the Queuing arrangement of E trade, the clients touches base in Batch with Reneging happens at the set-up time organize and Optional second stage where breakdown happens just as fix procedure will be done. Moreover, we accept that the clients may renege amid the Initial stage because of eagerness (Slow server) or Non-Satisfaction in acquiring the items from the specific site. At the season of Repair process, Strictly Non-acceptability of the clients is executed. The model is well analyzed and solved by supplementary variable method .The system performance measures are derived. Numerical analysis and graphical representation of the model clearly justifies the model to a fullest satisfaction.

In this paper, we study about a M/G/1 Queuing model with single stage of service. Service interrupts during the time of service. The server does not get into the repair process immediately. It gets into a Set up time stage for the prior work to be done. On completion of set up stage service, the server will get into the repair process consisting of two stages, in which first stage is compulsory and the second stage of service is optional. For the model defined, we get the steady state results in closed form in terms of the probability generating functions and all the other execution performance measures of the model defined.


Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2218
Author(s):  
Sylwia Słupik ◽  
Joanna Kos-Łabędowicz ◽  
Joanna Trzęsiok

The issue of energy behaviour among Polish consumers, and especially the motives and attitudes they manifest, is relatively under-researched. This article attempts to identify individual attitudes and beliefs of energy consumers using the example of the residents of the province of Silesia (Poland). The authors conducted the expert segmentation of respondents in terms of their motivation for saving energy, based on the results of their proprietary survey. The second stage of the study involved using a classification model that allowed for the characterisation of the obtained groups. Psychological and financial factors were of greatest significance, which is confirmed by the results of other studies. Nonetheless, the obtained results explicitly indicate the specificity of the region, which requires transformation towards a low-emission economy. Despite the initial stage of changes both in the awareness of the consumers and the public interventions of the authorities, it should be emphasized that a majority of the respondents—at least to a basic extent—declared taking energy-saving measures. Financial motives are predominant among the respondents, although pro-environmental motives can also be noticed, which might translate into increased involvement and concern for the environment and climate.


Mathematics ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 52
Author(s):  
José Niño-Mora

We consider the multi-armed bandit problem with penalties for switching that include setup delays and costs, extending the former results of the author for the special case with no switching delays. A priority index for projects with setup delays that characterizes, in part, optimal policies was introduced by Asawa and Teneketzis in 1996, yet without giving a means of computing it. We present a fast two-stage index computing method, which computes the continuation index (which applies when the project has been set up) in a first stage and certain extra quantities with cubic (arithmetic-operation) complexity in the number of project states and then computes the switching index (which applies when the project is not set up), in a second stage, with quadratic complexity. The approach is based on new methodological advances on restless bandit indexation, which are introduced and deployed herein, being motivated by the limitations of previous results, exploiting the fact that the aforementioned index is the Whittle index of the project in its restless reformulation. A numerical study demonstrates substantial runtime speed-ups of the new two-stage index algorithm versus a general one-stage Whittle index algorithm. The study further gives evidence that, in a multi-project setting, the index policy is consistently nearly optimal.


2021 ◽  
Vol 9 (1) ◽  
pp. 28-35
Author(s):  
Mariya Podshivalova ◽  
S. Almrshed

The starting point of research on assessing the innovative capacity of an enterprise is the question of definitions. In this regard, authors initially turned to review of scientific literature on the subject of definitions variety for the term "enterprise innovative capacity". These data show that the wording of this term by both foreign and Russian researchers differs significantly. Authors propose a systematization of approaches to the definition and a corresponding graphical classification model, which highlights the evolutionary, resource, functional and process approaches. Further, a critical analysis of approaches to assessing enterprise innovative capacity is carried out. At the first stage, the content of modern assessment methods was studied, and at the second stage, the mathematical tools used were studied. Authors have formed a graphical representation of critical analysis results and based on it, they have concluded that among the approaches to assessing enterprise innovative capacity, the evolutionary approach should be recognized as promising, and among the methods of quantitative assessment – tools of economic statistics.


2016 ◽  
Vol 5 (1) ◽  
Author(s):  
A. Pastorino ◽  
L. Todisco ◽  
E. Cazzulo ◽  
L. Berretta ◽  
A. Orecchia ◽  
...  

From mega-voltage portal images acquired on an electronic system (EPID), technological research has developed 3D and recently 4D volumetric verification modalities, allowing a direct visualization of the target, a direct comparison with the planning-TC and an optimization of the treatment (reduction of set-up errors, verification of the need for re-planning), leading to the very modern Image Guided RadioTherapy (IGRT). IGRT allows different technical solutions through direct or indirect visualization of the tumor and the acquisition of pre-treatment verification images, allowing to identify, quantify and correct errors related to set-up and organ-tumor motion, obtaining a greater compliance of the delivered dose, decreasing the risk of "geographic miss" and toxicity to healthy tissues and reducing the margins from CTV to PTV for the implementation of "dose escalation" protocols.


1981 ◽  
Vol 25 (03) ◽  
pp. 147-180
Author(s):  
Takao Inui

Trends of 20 years' research on ship waves at the Tokyo University Tank since 1960 are briefly sketched. Stress is focused on the importance of dialogues between man and nature. The process of these dialogues is exemplified by some typical cases, including the development of bulbous bows and the finding of free-surface shock waves. Wave-pattern pictures are shown to be indispensable for the initial stage of the di alogues, while wave contours and velocity-field measurements serve well in the second stage. The current wave analysis and wake survey may be the third. The relationship between "wavebreaking" and the "free-surface shock wave" is also discussed.


Author(s):  
Rizwan Aqeel ◽  
Saif Ur Rehman ◽  
Saira Gillani ◽  
Sohail Asghar

This chapter focuses on an Autonomous Ground Vehicle (AGV), also known as intelligent vehicle, which is a vehicle that can navigate without human supervision. AGV navigation over an unstructured road is a challenging task and is known research problem. This chapter is to detect road area from an unstructured environment by applying a proposed classification model. The Proposed model is sub divided into three stages: (1) - preprocessing has been performed in the initial stage; (2) - road area clustering has been done in the second stage; (3) - Finally, road pixel classification has been achieved. Furthermore, combination of classification as well as clustering is used in achieving our goals. K-means clustering algorithm is used to discover biggest cluster from road scene, second big cluster area has been classified as road or non road by using the well-known technique support vector machine. The Proposed approach is validated from extensive experiments carried out on RGB dataset, which shows that the successful detection of road area and is robust against diverse road conditions such as unstructured nature, different weather and lightening variations.


2020 ◽  
Vol 105 (9) ◽  
pp. e1.2-e2
Author(s):  
Nicola Wilson

Situation16 year old girl admitted with suspected ingestion of ethylene glycol. She was treated with fomepizole and continuous renal replacement therapy (CRRT).How the Pharmacy Team ContributedEthanol was prescribed until fomepizole arrived. The volume of ethanol to be administered was calculated wrongly by the consultant due to confusion about the available strength. The Paediatric Intensive Care Unit (PICU) pharmacist intervened and the correct dosage information was given.PICU pharmacist used Toxbase to determine the correct treatment of ethylene glycol poisoning and advised on dosing regime, including adjustment due to CRRT. The pharmacist facilitated prescribing on the electronic system (added drug to system, set up administration instructions and assisted with prescribing – pharmacist was not an Independent Prescriber). This allowed medical staff to concentrate on resuscitation, monitoring cardiac function, inserting intravenous lines and obtaining access for CRRT.The PICU pharmacist and pharmacy technician co-ordinated initial supply of fomepizole. Fomepizole is usually ordered directly from the manufacturer during office hours. The patient presented in the early evening so further supply had to be obtained from a hospital hundreds of miles away after referring to the Rarely Used Medicines list. Pharmacist contacted appropriate on-call pharmacist and arranged for transfer of medicines via courier. Pharmacy technician arranged for further supply form the manufacturer the following day.Pharmacy technician arranged supply of additional dialysis fluids for CRRT due to the higher than usual administration rate.Without contribution from the pharmacy team the patient is likely to have been given the wrong dose of ethanol and fomepizole, and there would have been delay in initiation of treatment followed by an interruption, as it was wrongly assumed that it was kept as stock in the adjoining ‘adult hospital’ and subsequent supply from a local hospital would not have been sought by ward staff until original supply ran out.OutcomeEthylene glycol poisoning was confirmed on laboratory testing. Levels of ethylene glycol fell steadily over 36 hours, allowing CRRT and fomepizole to stop. Patient was discharged from PICU after 48 hours with no apparent long-lasting effects, but was referred to various specialities including renal, gastroenterology and psychology.Patient and family denied knowledge of intentional or accidental ingestion. Police investigation was inconclusive.Lessons to be LearnedLarger supplies of fomepizole are now kept in stock within Health Board. Supplies were missing from emergency cupboards when stock was needed, despite being on stock lists, necessitating courier fees to transfer stock from elsewhere. Procedures reviewed to ensure that stock is available in emergency cupboards at all times.This patient demonstrated that current (target) stock levels of fomepizole were inadequate for providing treatment during CRRT as the required doses are substantially higher (administered every four hours rather than every twelve hours) and would have lasted less than 12 hours for this average sized teenager. National Rarely Used Medicines list was updated to reflect actual stock levels and other hospitals increased their stockholding due to the realisation that existing stock was inadequate and that further supplies were hard to obtain out of working hours.


2019 ◽  
Vol 79 (10) ◽  
pp. 1060-1078 ◽  
Author(s):  
Hans-Georg Schnürch ◽  
Sven Ackermann ◽  
Celine D. Alt-Radtke ◽  
Lukas Angleitner ◽  
Jana Barinoff ◽  
...  

Abstract Purpose This is an official guideline, published and coordinated by the Gynecological Oncology Working Group (AGO) of the German Cancer Society (DKG) and the German Society for Gynecology and Obstetrics (DGGG). Vaginal cancers are rare tumors, which is why there is very little evidence on these tumors. Knowledge about the optimal clinical management is limited. This first German S2k guideline on vaginal cancer has aimed to compile the most current expert knowledge and offer new recommendations on the appropriate treatment as well as providing pointers about individually adapted therapies with lower morbidity rates than were previously generally available. The purpose of this guideline is also to set up a register to record data on treatment data and the course of disease as a means of obtaining evidence in future. Methods The present S2k guideline was developed by members of the Vulvar und Vaginal Tumors Commission of the AGO in an independently moderated, structured, formal consensus process and the contents were agreed with the mandate holders of the participating scientific societies and organizations. Recommendations To optimize the daily care of patients with vaginal cancer: 1. Monitor the spread pattern; 2. Follow the step-by-step diagnostic workup based on initial stage at detection; 3. As part of individualized clinical therapeutic management of vaginal cancer, follow the sentinel lymph node protocol described here, where possible; 4. Participate in the register study on vaginal cancer.


1991 ◽  
Vol 235 ◽  
Author(s):  
Q. Z. Hong ◽  
J. M. E. Harper

ABSTRACTThe temperature dependence of 300 eV argon ion sputtering of CoSi2 thin films in the range 50–600°C has been investigated. At temperatures above 400°C, the etch rate of CoSi2 on Si is significantly reduced, while the underlying Si reacts with the Co atoms diffusing from the silicide surface. As a result, the silicide layer effectively moves into the substrate during Ar bombardment. During sputtering of CoSi2 on Sio2, the thickness of the silicide layer decreases almost linearly with bombarding time until all the silicide is removed. Similar behavior is observed in low temperature sputtering of CoSi2 on (100) Si and evaporated Si. However, at elevated temperatures (400°C< <600°C), sputtering of CoSi2 on Si undergoes two consecutive stages. During the initial stage, the thickness of the silicide layer decreases at the same rate as that of the silicide on SiO2, and is accompanied by an enrichment in Co concentration near the surface. During the second stage, the etch rate of the silicide is reduced to only one third of the rate during the initial stage.


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