scholarly journals Largely reduced OAR doses, and planning and delivery times for challenging robotic SBRT cases, obtained with a novel optimizer

2021 ◽  
Author(s):  
Marta K. Giżyńska ◽  
Linda Rossi ◽  
Wilhelm Toom ◽  
Maaike T. W. Milder ◽  
Kim C. Vries ◽  
...  
Keyword(s):  
Delivery Times

Decompensation placental dysfunction: diagnostics and delivery tactics

2017 ◽  
pp. 66-68
Author(s):  
V.I. Boyko ◽  
◽  
S.A. Tkachenko ◽  
Keyword(s):  
Pregnant Women ◽  
Key Words ◽  
Retrospective Analysis ◽  
Control Group ◽  
Present Stage ◽  
Placental Dysfunction ◽  
Perinatal Pathology ◽  
Delivery Times ◽  
Case Rate ◽  
Major Factors

The objective: depression of frequency of perinatal pathology at women with decompensation form of placental dysfunction by improvement of the main diagnostic and treatment-and-prophylactic actions. Patients and methods. 154 pregnant women in gestation term from 22 to 40 weeks were surveyed. Depending on features of course of pregnancy and families of all surveyed it was divided into 4 groups. The group of the retrospective analysis was made by 45 pregnant women with decompensation placental dysfuction, the group of prospective research included 109 pregnant women of whom the main group was made by 38 women with decompensation form of placental dysfunction, the group of comparison included 47 pregnant women with the compensated form of placental dysfunction. The control group was made by 24 pregnant women with the uncomplicated course of pregnancy and labors. The complex of the conducted researches included clinical, ehografical, dopplerometrical, laboratory, morphological and statistical methods. Results. Use of advanced algorithm of diagnostic and treatment-and-prophylactic actions allows to increase efficiency of diagnostics of decompensation form of placental dysfunction for 33.3%, and rational tactics of a delivery leads to depression of perinatal pathology for 22.7%. Conclusion. Decompensation placental dysfuction is one of the main reasons for perinatal mortality and a case rate at the present stage. Use of the algorithm of diagnostic and treatment-and-prophylactic actions improved by us allows major factors of risk of this complication and the indication for change of tactics and delivery times. Key words: decompensation placental dysfunction, diagnostics, delivery tactics.

scholarly journals Dosimetric comparison of MR-linac-based IMRT and conventional VMAT treatment plans for prostate cancer

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Vanessa Da Silva Mendes ◽  
Lukas Nierer ◽  
Minglun Li ◽  
Stefanie Corradini ◽  
Michael Reiner ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Target Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Coverage ◽  
Treatment Delivery ◽  
Ptv Margin ◽  
Delivery Times ◽  
Low Field ◽  
Treatment Plans

Abstract Background The aim of this study was to evaluate and compare the performance of intensity modulated radiation therapy (IMRT) plans, planned for low-field strength magnetic resonance (MR) guided linear accelerator (linac) delivery (labelled IMRT MRL plans), and clinical conventional volumetric modulated arc therapy (VMAT) plans, for the treatment of prostate cancer (PCa). Both plans used the original planning target volume (PTV) margins. Additionally, the potential dosimetric benefits of MR-guidance were estimated, by creating IMRT MRL plans using smaller PTV margins. Materials and methods 20 PCa patients previously treated with conventional VMAT were considered. For each patient, two different IMRT MRL plans using the low-field MR-linac treatment planning system were created: one with original (orig.) PTV margins and the other with reduced (red.) PTV margins. Dose indices related to target coverage, as well as dose-volume histogram (DVH) parameters for the target and organs at risk (OAR) were compared. Additionally, the estimated treatment delivery times and the number of monitor units (MU) of each plan were evaluated. Results The dose distribution in the high dose region and the target volume DVH parameters (D98%, D50%, D2% and V95%) were similar for all three types of treatment plans, with deviations below 1% in most cases. Both IMRT MRL plans (orig. and red. PTV margins) showed similar homogeneity indices (HI), however worse values for the conformity index (CI) were also found when compared to VMAT. The IMRT MRL plans showed similar OAR sparing when the orig. PTV margins were used but a significantly better sparing was feasible when red. PTV margins were applied. Higher number of MU and longer predicted treatment delivery times were seen for both IMRT MRL plans. Conclusions A comparable plan quality between VMAT and IMRT MRL plans was achieved, when applying the same PTV margin. However, online MR-guided adaptive radiotherapy allows for a reduction of PTV margins. With a red. PTV margin, better sparing of the surrounding tissues can be achieved, while maintaining adequate target coverage. Nonetheless, longer treatment delivery times, characteristic for the IMRT technique, have to be expected.

scholarly journals Organ motion in linac-based SBRT for glottic cancer

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Annarita Perillo ◽  
Valeria Landoni ◽  
Alessia Farneti ◽  
Giuseppe Sanguineti
Keyword(s):  
Early Stage ◽  
Displacement Vector ◽  
Thyroid Cartilage ◽  
Three Dimensional ◽  
Target Volume ◽  
Glottic Cancer ◽  
Organ Motion ◽  
Delivery Times ◽  
Significant Difference ◽  
Pre Treatment

Abstract Purpose The purpose of this study is to evaluate inter- and intra-fraction organ motion as well as to quantify clinical target volume (CTV) to planning target volume (PTV) margins to be adopted in the stereotactic treatment of early stage glottic cancer. Methods and materials Stereotactic body radiotherapy (SBRT) to 36 Gy in 3 fractions was administered to 23 patients with early glottic cancer T1N0M0. Patients were irradiated with a volumetric intensity modulated arc technique delivered with 6 MV FFF energy. Each patient underwent a pre-treatment cone beam computed tomography (CBCT) to correct the setup based on the thyroid cartilage position. Imaging was repeated if displacement exceeded 2 mm in any direction. CBCT imaging was also performed after each treatment arc as well as at the end of the delivery. Swallowing was allowed only during the beam-off time between arcs. CBCT images were reviewed to evaluate inter- and intra-fraction organ motion. The relationships between selected treatment characteristics, both beam-on and delivery times as well as organ motion were investigated. Results For the population systematic (Ʃ) and random (σ) inter-fraction errors were 0.9, 1.3 and 0.6 mm and 1.1, 1.3 and 0.7 mm in the left-right (X), cranio-caudal (Y) and antero-posterior (Z) directions, respectively. From the analysis of CBCT images acquired after treatment, systematic (Ʃ) and random (σ) intra-fraction errors resulted 0.7, 1.6 and 0.7 mm and 1.0, 1.5 and 0.6 mm in the X, Y and Z directions, respectively. Margins calculated from the intra-fraction errors were 2.4, 5.1 and 2.2 mm in the X, Y and Z directions respectively. A statistically significant difference was found for the displacement in the Z direction between patients irradiated with > 2 arcs versus ≤ 2 arcs, (MW test, p = 0.038). When analyzing mean data from CBCT images for the whole treatment, a significant correlation was found between the time of delivery and the three dimensional displacement vector (r = 0.489, p = 0.055), the displacement in the Y direction (r = 0.553, p = 0.026) and the subsequent margins to be adopted (r = 0.626, p = 0.009). Finally, displacements and the subsequent margins to be adopted in Y direction were significantly greater for treatments with more than 2 arcs (MW test p = 0.037 and p = 0.019, respectively). Conclusions In the setting of controlled swallowing during treatment delivery, intra-fraction motion still needs to be taken into account when planning with estimated CTV to PTV margins of 3, 5 and 3 mm in the X, Y and Z directions, respectively. Selected treatments may require additional margins.

scholarly journals Driver Shift Planning for an Online Store with Short Delivery Times

2021 ◽  
Vol 180 ◽  
pp. 517-524
Author(s):  
Matthias Horn ◽  
Nikolaus Frohner ◽  
Günther R. Raidl
Keyword(s):  
Online Store ◽  
Delivery Times ◽  
Shift Planning

scholarly journals Cost Analysis of a Novel Method for Ecological Compensation—A Study of the Translocation of Dead Wood

2021 ◽  
Vol 13 (11) ◽  
pp. 6075
Author(s):  
Ola Lindroos ◽  
Malin Söderlind ◽  
Joel Jensen ◽  
Joakim Hjältén
Keyword(s):  
Cost Efficiency ◽  
Dead Wood ◽  
Road Transportation ◽  
Ecological Value ◽  
Ecological Compensation ◽  
Work Time ◽  
Delivery Times ◽  
Novel Method ◽  
Cost Efficient ◽  
The Cost

Translocation of dead wood is a novel method for ecological compensation and restoration that could, potentially, provide a new important tool for biodiversity conservation. With this method, substrates that normally have long delivery times are instantly created in a compensation area, and ideally many of the associated dead wood dwelling organisms are translocated together with the substrates. However, to a large extent, there is a lack of knowledge about the cost efficiency of different methods of ecological compensation. Therefore, the costs for different parts of a translocation process and its dependency on some influencing factors were studied. The observed cost was 465 SEK per translocated log for the actual compensation measure, with an additional 349 SEK/log for work to enable evaluation of the translocation’s ecological results. Based on time studies, models were developed to predict required work time and costs for different transportation distances and load sizes. Those models indicated that short extraction and insertion distances for logs should be prioritized over road transportation distances to minimize costs. They also highlighted a trade-off between costs and time until a given ecological value is reached in the compensation area. The methodology used can contribute to more cost-efficient operations and, by doing so, increase the use of ecological compensation and the benefits from a given input.

scholarly journals Collaborative Robots and Knowledge Management - A Short Review

2017 ◽  
Vol 69 (1) ◽  
pp. 143-147 ◽  
Author(s):  
Flaviu-Constantin Mușat ◽  
Florin-Constantin Mihu
Keyword(s):  
Knowledge Management ◽  
Management System ◽  
Short Review ◽  
Knowledge Management System ◽  
Work Place ◽  
Collaborative Robots ◽  
Delivery Times ◽  
Parallel Tasks ◽  
To Come ◽  
Automated Lines

Abstract Because the requirements of the customers are more and more high related to quality, quantity, delivery times at lowest costs possible, the industry had to come with automated solutions to improve these requirements. Starting from the automated lines developed by Ford and Toyota, we have now developed automated and self-sustained working lines, which is possible nowadays-using collaborative robots. By using the knowledge management system we can improve the development of the future of this kind of area of research. This paper shows the benefits and the smartness use of the robots that are performing the manipulation activities that increases the work place ergonomically and improve the interaction between human - machine in order to assist in parallel tasks and lowering the physically human efforts.

A best on-line algorithm for the single machine parallel-batch scheduling with restricted delivery times

2007 ◽  
Vol 17 (2) ◽  
pp. 206-213 ◽  
Author(s):  
Jinjiang Yuan ◽  
Shisheng Li ◽  
Ji Tian ◽  
Ruyan Fu
Keyword(s):  
Single Machine ◽  
Batch Scheduling ◽  
Delivery Times ◽  
On Line

PPS als Integrationsplattform*/PPS as integration platform. Efficient networking of production supporting IT systems

2019 ◽  
Vol 109 (05) ◽  
pp. 377-381
Author(s):  
C. Brecher ◽  
C. Fimmers ◽  
P. Blanke ◽  
S Storms ◽  
W. Herfs
Keyword(s):  
Control System ◽  
Production Planning ◽  
Production Planning And Control ◽  
Integration Platform ◽  
Planning And Control ◽  
Delivery Times ◽  
Kleine Und Mittlere Unternehmen ◽  
It Systems ◽  
And Control

In der heutigen Zeit sind durch steigende Variantenvielfalt und Individualfertigung sowie enge Lieferzeiten unterstützende IT-Systeme in der Fertigung unerlässlich. Gerade für kleine und mittlere Unternehmen (KMU) stellt dies eine Herausforderung dar, weil individuelle Schnittstellenentwicklungen und maschinenspezifische Anbindungen zeit- und kostenintensiv sind. Mit einer Produktionsplanungs- und Steuerungssystem als Integrationsplattform sowie einer allgemeingültige Schnittstelle zur Maschinenanbindung kann dem bestehenden Handlungsbedarf entsprochen werden.   Nowadays, due to the increasing variety of variants and individual production as well as tight delivery times, supporting IT systems are indispensable in production. This poses a particular challenge for SMEs, since individual interface developments and machine-specific connections are time-consuming and costly. These challenges can be met by using a Production Planning and Control system as an integration platform and a generally valid interface to the machine connection.

Rekonfiguration von Produktionsnetzwerken*/Planning of reconfigurable production networks

2018 ◽  
Vol 108 (03) ◽  
pp. 137-142
Author(s):  
J. Atug ◽  
S. Braunreuther ◽  
G. Reinhart
Keyword(s):  
Production Planning ◽  
Wird Eine ◽  
Production Networks ◽  
Short Term ◽  
Delivery Times ◽  
Future Production ◽  
Planning Approach ◽  
High Adherence ◽  
Demand Volatility ◽  
Increasing Demand

Starke Nachfrageschwankungen insbesondere in der auftragsbezogenen Produktion sowie die Forderung nach kürzeren Lieferzeiten und höherer Termintreue führen zu erhöhten Anforderungen an die zukünftige Produktion. Um diesen Anforderungen gerecht zu werden, bedarf es dynamischer Produktionsnetzwerke. In diesem Fachbeitrag wird eine Methode zur kurzfristigen Anpassung von Produktionsnetzwerken durch Rekonfiguration in der auftragsbezogenen Produktion vorgestellt.   Increasing demand volatility in order-based production as well as the need of shorter delivery times and high adherence to schedules leads to high requirements of the future production. To meet these essential requirements dynamic production networks are needed. In this technical contribution a production planning approach of short-term reconfiguration of production networks in the order-based production is given.

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