scholarly journals An Open-Source Framework of Generating Network-Based Transit Catchment Areas by Walking

2020 ◽  
Vol 9 (8) ◽  
pp. 467
Author(s):  
Diao Lin ◽  
Ruoxin Zhu ◽  
Jian Yang ◽  
Liqiu Meng
Keyword(s):  
Open Source ◽  
Road Network ◽  
Related Factors ◽  
Shortest Path Tree ◽  
Source Program ◽  
Tree Construction ◽  
Catchment Areas ◽  
Open Source Framework ◽  
Support Research

The transit catchment area is an important concept for public transport planning. This study proposes a methodological framework to generate network-based transit catchment areas by walking. Three components of the framework, namely subgraph construction, extended shortest path tree construction and contour generation are presented step by step. Methods on how to generalize the framework to the cases of the directed road network and non-point facilities are developed. The implementation of the framework is provided as an open-source project. Using metro stations in Shanghai as a case study, we illustrate the feasibility of the proposed framework. Experiments show that the proposed method generates catchment areas of high geospatial accuracy and significantly increases computational efficiency. The open-source program can be applied to support research related to transit catchment areas and has the potential to be extended to include more routing-related factors.

Benefits and Pitfalls of Open Source in Commercial Contexts

2005 ◽  
pp. 222-241 ◽  
Author(s):  
Jiayin Hang ◽  
Heidi Hohensohn ◽  
Klaus Mayr ◽  
Thomas Wieland
Keyword(s):  
Decision Making ◽  
Open Source ◽  
Lessons Learned ◽  
Commercial Product ◽  
Decision Making Process ◽  
Business Opportunity ◽  
Open Source Framework ◽  
Open Source Communities ◽  
Communication Culture

This chapter intends to show how companies can benefit from open source software and its development culture and how the open source communities could, in turn, be stimulated and accelerated. One of the first major steps for businesses that plan to act in this context is to accept that open source projects have their own communication culture. After explaining this fact, we illustrate its relevance on the basis of a case study in which an open source framework was used to build a commercial product. The decision-making process and the lessons learned from it point out some guidelines, particularly for companies that offer projects rather than products. As there are, however, more parties involved than just the developers when OSS is discussed as a business opportunity, we also classify the different players in the software business such as distributors, system integrators, and software/hardware vendors. Findings on roles and their motivations and restraints, partially based on a survey carried out within our research project, point up this categorization. The authors hope that this overview of the benefits and pitfalls will encourage more companies to make use of and invest in the open source way to develop and deploy software.

scholarly journals pygrametl: A Powerful Programming Framework for Easy Creation and Testing of ETL Flows

2021 ◽  
pp. 45-84
Author(s):  
Søren Kejser Jensen ◽  
Christian Thomsen ◽  
Torben Bach Pedersen ◽  
Ove Andersen
Keyword(s):  
Open Source ◽  
User Interfaces ◽  
Graphical User Interfaces ◽  
Time Performance ◽  
Programming Framework ◽  
Open Source Framework ◽  
Full Power ◽  
Single Method ◽  
A Company

AbstractExtract-Transform-Load (ETL) flows are used to extract data, transform it, and load it into data warehouses (DWs). The dominating ETL tools use graphical user interfaces (GUIs) where users must manually place steps/components on a canvas and manually connect them using lines. This provides an easy to understand overview of the ETL flow but can also be rather tedious and require much trivial work for simple things. We, therefore, challenge this approach and propose to develop ETL flows by writing code. To make the programming easy, we proposed the Python-based ETL framework in 2009. We have extended significantly since the original release, and in this paper, we present an up-to-date overview of the framework. offers commonly used functionality for programmatic ETL development and enables the user to efficiently create effective ETL flows with the full power of programming. Each dimension is represented by a dimension object that manages the underlying table or tables in the case of a snowflaked dimension. Thus, filling a slowly changing or snowflaked dimension only requires a single method call per row as performs all of the required lookups, insertions, and assignment of surrogate keys. Similarly to dimensions, fact tables are each represented by a fact table object. Our latest addition to , Drawn Table Testing (DTT), simplifies testing ETL flows by making it easy to define both preconditions (i.e., the state of the database before the ETL flow is run) and postconditions (i.e., the expected state after the ETL flow has run) into a test. DTT can also be used to test ETL flows created in other ETL tools. also provides a set of commonly used functions for transforming rows, classes that help users parallelize their ETL flows using simple abstractions, and editor support for working with DTT. We present an evaluation that shows that provides high programmer productivity and that the created ETL flows have good run-time performance. Last, we present a case study from a company using in production and consider some of the lessons we learned during the development of as an open source framework.

scholarly journals SODALITE@RT: Orchestrating Applications on Cloud-Edge Infrastructures

2021 ◽  
Vol 19 (3) ◽  
Author(s):  
Indika Kumara ◽  
Paul Mundt ◽  
Kamil Tokmakov ◽  
Dragan Radolović ◽  
Alexander Maslennikov ◽  
...  
Keyword(s):  
Open Source ◽  
Open Source Framework ◽  
Relevant Case ◽  
Crucial Problem ◽  
Open Standards

AbstractIoT-based applications need to be dynamically orchestrated on cloud-edge infrastructures for reasons such as performance, regulations, or cost. In this context, a crucial problem is facilitating the work of DevOps teams in deploying, monitoring, and managing such applications by providing necessary tools and platforms. The SODALITE@RT open-source framework aims at addressing this scenario. In this paper, we present the main features of the SODALITE@RT: modeling of cloud-edge resources and applications using open standards and infrastructural code, and automated deployment, monitoring, and management of the applications in the target infrastructures based on such models. The capabilities of the SODALITE@RT are demonstrated through a relevant case study.

OpenPlaning: Open-Source Framework for the Hydrodynamic Design of Planing Hulls

2021 ◽  
Author(s):  
Esteban L. Castro-Feliciano
Keyword(s):  
Linear System ◽  
Open Source ◽  
Control Systems ◽  
Exact Results ◽  
Empirical Methods ◽  
Planing Craft ◽  
Tuning Parameters ◽  
Root Finding ◽  
Open Source Framework

The use of Dr. Savitsky's empirical methods for the hydrodynamic design of planing hulls is widespread in industry and academia. In spite of their common use, their implementations are frequently inconsistent among their users. This makes it difficult to share and replicate exact results, and apply those results to a reader's desired case study. This paper presents an open-source Python-based framework of the Savitsky '64 and Savitksy & Brown '76 papers that is suitable for industry and research purposes, named OpenPlaning. The original Savitsky method implementation required the use of charts and results interpolation to find the boat's equilibrium. OpenPlaning instead uses a root-finding algorithm to determine the equilibrium attitude, automating the process and assuring consistent use of the Savitsky method. This formulaic approach allows the users to change and explore variations among any desired hull characteristic (beam, deadrise, weight, flap size/deflection, etc.), and use Python packages to optimize these parameters. OpenPlaning includes Faltinsen's 2010 planing hull porpoising inception work, which expanded upon the Savitsky method to estimate the vessel's mass, damping, and restoring coefficients. Consequently, control engineers can also use OpenPlaning to obtain a linear system in the heave and pitch degree of freedoms, and obtain initial tuning parameters for control systems. To illustrate the use of OpenPlaning, an example planing craft is designed, explored and optimized with real-world constraints.

Hodgkin Disease and Pregnancy - A Case Report

2014 ◽  
Vol 68 (2) ◽  
pp. 104-106
Author(s):  
Aleksandra Pivkova Veljanovska ◽  
Sonja Genadieva Stavrik ◽  
Zlate Stojanoski ◽  
Lazar Cadievski ◽  
Adela Stefanija ◽  
...  
Keyword(s):  
Case Report ◽  
Pregnant Women ◽  
Hodgkin Disease ◽  
Morbidity And Mortality ◽  
Chemotherapy Treatment ◽  
Related Factors ◽  
Hematological Disorder

Abstract The article presents a case with diagnosed Hodgkin disease (HD) during pregnancy. The aim of this case study was to present diagnostic possibilities in determining HD stage during pregnancy and therapeutic dilemmas. The incidence of HD during pregnancy is 3.2% of all cases with this malignant hematological disorder. The treatment of this disease during pregnancy depends on disease-related factors, pregnancy-related factors, as well as possible implications for fetal morbidity and mortality. The need of analysis of the nature of the disease during pregnancy indicates examination of a larger series of pregnant women with HD and the drawn conclusions affect the decision whether chemotherapy treatment should start immediately or it should be postponed for after delivery.

Optimales Layout einer Walderschliessung

2016 ◽  
Vol 167 (5) ◽  
pp. 294-301
Author(s):  
Leo Bont
Keyword(s):  
Road Network ◽  
Spatial Arrangement ◽  
Problem Situation ◽  
Optimal Layout ◽  
Forest Road ◽  
The Road ◽  
Network Cost ◽  
User Friendly ◽  
Short Time

Optimal layout of a forest road network The road network is the backbone of forest management. When creating or redesigning a forest road network, one important question is how to shape the layout, this means to fix the spatial arrangement and the dimensioning standard of the roads. We consider two kinds of layout problems. First, new forest road network in an area without any such development yet, and second, redesign of existing road network for actual requirements. For each problem situation, we will present a method that allows to detect automatically the optimal road and harvesting layout. The method aims to identify a road network that concurrently minimizes the harvesting cost, the road network cost (construction and maintenance) and the hauling cost over the entire life cycle. Ecological issues can be considered as well. The method will be presented and discussed with the help of two case studies. The main benefit of the application of optimization tools consists in an objective-based planning, which allows to check and compare different scenarios and objectives within a short time. The responses coming from the case study regions were highly positive: practitioners suggest to make those methods a standard practice and to further develop the prototype to a user-friendly expert software.

Performance Comparison of Web Backend And Database: A Case Study Of Node.JS, Golang and MySQL, MongoDB

2019 ◽  
Vol 13 ◽  
Author(s):  
Faried Effendy ◽  
Taufik ◽  
Bramantyo Adhilaksono
Keyword(s):  
Response Time ◽  
Open Source ◽  
Poisson Distribution ◽  
Mobile Application ◽  
Web Applications ◽  
Performance Comparison ◽  
Memory Usage ◽  
Data Traffic ◽  
Cpu Utilization

: Substantial research has been conducted to compare web servers or to compare databases, but very limited research combines the two. Node.js and Golang (Go) are popular platforms for both web and mobile application back-ends, whereas MySQL and Go are among the best open source databases with different characters. Using MySQL and MongoDB as databases, this study aims to compare the performance of Go and Node.js as web applications back-end regarding response time, CPU utilization, and memory usage. To simulate the actual web server workload, the flow of data traffic on the server follows the Poisson distribution. The result shows that the combination of Go and MySQL is superior in CPU utilization and memory usage, while the Node.js and MySQL combination is superior in response time.

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