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The purpose of this paper is to present an approach to a polar graph measurement by a flight testing technique and to propose a baseline research method for future tests of UAV polar graphs. The method presented can be used to demonstrate a conceptual and preliminary design process using a scaled, unmanned configuration. This shows how results of experimental flight tests using a scaled flying airframe may be described and analysed before manufacturing the full scale aircraft.

During the research, the flight tests were conducted for two aerodynamic configurations of a small UAV. This allowed the investigation of the influence of winglets and classic vertical stabilizers on the platform stability, performance and therefore polar graphs of a small unmanned aircraft.

A methodology of flight tests for the assessment of a small UAV’s polar graph has been proposed, performed and assessed. Two aerodynamic configurations were tested, and it was found that directional stability had a large influence on the UAV’s performance. A correlation between the speed and inclination of the altitude graph was found – i.e. the higher the flight speed, the steeper the altitude graph (higher descent speed, steeper flight path angle). This could be considered as a basic verification that the recorded data have a physical sense.

The polar graph and therefore glide ratio of the aircraft is a major factor for determining its performance and power required for flight. Using the right flight test procedure can speed-up the process of measuring glide ratio, making it easier, faster, robust, more effective and accurate in future research of novel, especially unorthodox configurations. This paper also can be useful for the proper selection of requirements and preliminary design parameters for making the design process more economically effective.

This paper presents a very efficient method of assessing the design parameters of UAVs, especially the polar graph, in an early stage of the design process. Aircraft designers and producers have been widely performing flight testing for years. However, these procedures and practical customs are usually not wide spread and very often are treated as the company’s “know how”. Results presented in this paper are original, relatively easily be repeated and checked. They may be used either by professionals, highly motivated individuals and representatives of small companies or also by ambitious amateurs.

Benchmarking is the search for best practices that will lead to superior performance in some business activity. Benchmarking can provide organisations with various benefits in process improvement, culture and, in actual financial terms, benchmarking can provide tremendous leverage. The generic process of benchmarking consists of four main steps, namely: plan, collect, analyse and adapt. A major part of the “plan” step is the benchmarking partner selection phase. This is arguably one of the most crucial factors for success. It involves analysing various attributes ranging from technical issues to cultural aspects. Clearly, this complicates the decision process for practitioners, but if this step is not accomplished properly, the organisation is unlikely to achieve effective results from its benchmarking initiative. In order to improve the chances of successful partner selection for benchmarking, multi‐attribute decision‐making tools are recommended. Explains how to use graphical techniques in order to evaluate the best practice among the potential candidates for benchmarking.

IN today's battle for greater productivity management is cast in a cardinal role. Like a military commander, it has first to recognize the nature and purpose of the opponent and then formulate the best strategy to encompass his defeat. One element in that is to know the strength and quality of the available resources, ways in which to improve both, and then deploy them to the best advantage.

This study explores the use of the information theory entropy equation in representations of videos for children. The calculated rates of information in the videos are calibrated to the corresponding perceived rates of information as elicited from the 12 seven‐ to ten‐year‐old girls who were shown video documents. Entropy measures are calculated for several video elements: set time, set incidence, verbal time, verbal incidence, set constraint, nonverbal dependence, and character appearance. As hypothesized, mechanically calculated entropy measure (CEM) was found to be sufficiently similar to perceived entropy measure (PEM) made by children so that they can be used as useful and predictive elements of representations of children's videos. The relationships between the CEM and the PEM show that CEM could stand for PEM in order to enrich representations for video documents for this age group.

While previous studies focused mainly on East Asia to Europe or United States trade routes, in recent years, trade among South-East Asian countries has increased notably. The price of transporting a container is not fixed and can fluctuate heavily over the course of a week. Besides, extant literature only identified seasonality patterns in the container freight market, but did not explore route-varying seasonality patterns. Hence, this study analyses container freight seasonality patterns of the six South-East Asian routes of the South-East Asian Freight Index (SEAFI) and the index itself and forecasts them.

Data of the composite SEAFI and six routes are collected from the Shanghai Shipping Exchange (SSE) including 167 weekly observations from 2016 to 2019. The SEAFI and individual route data reflect spot rates from the Shanghai Port to South-East Asia base ports. The authors analyse seasonality patterns using polar plots. For forecasting, the study utilize two univariate models, autoregressive integrated moving average (ARIMA) and seasonal autoregressive neural network (SNNAR). For both models, the authors compare forecasting results of original level and log-transformed data.

This study finds that the seasonality patterns of the six South-East Asian container trade routes are identical in an overall but exhibits unique characteristics. ARIMA models perform better than SNNAR models for one-week ahead test-sample forecasting. The SNNAR models offer better performance for 4-week ahead forecasting for two selected routes only.

Major industry players such as shipping lines, shippers, ship-owners and others should take into account the route-level seasonality patterns in their decision-making. Forecast analysts can consider using the original level data without log transformation in their analysis. The authors suggest using ARIMA models in one-step and four-step ahead forecasting for majority of the routes. The SNNAR models are recommended for multi-step forecasting for Shanghai to Vietnam and Shanghai to Thailand routes only.

This study analyses a new shipping index, that is, the SEAFI and its underlying six routes. The authors analyze the seasonality pattern of container freight rate data using polar plot and perform forecasting using ARIMA and SNNAR models. Moreover, the authors experiment forecasting performance of log-transformed and non-transformed series.

The Talydata graphical display system and modular electronics and recorders for use on all future RPI Talyrond roundness measuring instruments comprises a small, very fast, dedicated computer. Contained in just a few printed circuit boards, it will perform all the calculations needed to display the roundness graph on a cathode ray tube, and to display simultaneously either the least squares circle, or inscribed or circumscribed circles, or the minimum zone circles. During the first revolution of the measuring table signals from the measuring probe are fed into the computer store and a display obtained if required. During the second, the calculations made and applied to centre the workpiece; and a third revolution is required to obtain the centred least squares circle, or whatever measuring parameter is selected by pushbutton, displayed superimposed on the roundness graph. The graphical display means that in routine inspection applications the conventional paper disc polar graph need only be produced when something unusual is shown on the display.

Some parameters and techniques in use for describing the results of tests on IR systems are analysed. Several considerations outside the scope of the usual 2 x 2 table are relevant to the choice of parameters. In particular, a variable which produces a ‘performance curve’ of a system corresponds to an extension of the 2 x 2 table. Also, the statistical relationships between parameters are all‐important. It is considered that precision is not such a useful measure of performance (in conjunction with recall) as fallout. A more powerful alternative to Cleverdon's ‘inevitable inverse relationship between recall and precision’ is proposed and justified, namely that the recall‐fallout graph is convex.

In recent years, the increasing complexity of the hyper-connected world demands new approaches for social network analysis. The main challenges are to find new computational methods that allow the representation, characterization and analysis of these social networks. Nowadays, formal concept analysis (FCA) is considered an alternative to identifying conceptual structures in a social network. In this FCA-based work, this paper aims to show the potential of building computational models based on implications to represent and analyze two-mode networks.

This study proposes an approach to find three important substructures in social networks such as conservative access patterns, minimum behavior patterns and canonical access patterns. The present study approach considered as a case study a database containing the access logs of a cable internet service provider.

The result allows us to uncover access patterns, conservative access patterns and minimum access behavior patterns. Furthermore, through the use of implications sets, the relationships between event-type elements (websites) in two-mode networks are analyzed. This paper discusses, in a generic form, the adopted procedures that can be extended to other social networks.

A new approach is proposed for the identification of conservative behavior in two-mode networks. The proper implications needed to handle minimum behavior pattern in two-mode networks is also proposed to be analyzed. The one-item conclusion implications are easy to understand and can be more relevant to anyone looking for one particular website access pattern. Finally, a method for a canonical behavior representation in two-mode networks using a canonical set of implications (steam base), which present a minimal set of implications without loss of information, is proposed.

A numerical method is presented for analysis of the pneumatic forming process of axisymmetric superplastic thin shells. The governing non‐linear partial differential equations are derived from membrane shell theory, using total Lagrangian description and considering a hardening creep material model. The method of lines used in the computational algorithm, involves two steps: first the Cauchy problem in time is considered, then the boundary problem is solved by finite differences. The effectiveness of the proposed algorithm is illustrated by several examples.

Increasing endurance was a very appropriate subject for the biomimetic approach. The study aims to design and manufacture a long-lasting mini unmanned aerial vehicle (UAV) using active gliding and soaring.

The endurance of mini UAVs is limited by battery or fuel capacity, and it is not always possible to increase these energy sources due to the fuselage size. Long endurance aircraft are required in various areas such as silent environment and traffic monitoring or search and rescue. Literature research on bird flight performance conducted to determine design parameters. These parameters are used in the theoretical design of the UAV for optimization. Computational fluid dynamics simulation and flight tests of the UAV performed to figure out the success of the design.

For a mini UAV to be produced in this class, it has been observed that it is more accurate to examine birds instead of gliders due to the size similarity. The UAV design reaches a 27.5 L/D (Glide ratio) ratio in the theoretical approach. However, flight results approved max L/D ratio is around 25 at the sea level. This flight performance is enough to outperform in glide ratio of Wandering albatrosses.

Sailplanes are known as sport aircraft. However, recent projects focus on glider designs due to fuel efficiency and silent tracking. Stemme S-14 that carries a high-resolution camera is one of the examples of these projects. The unmanned glider design can lead to these implications in the UAVs at least during the stand-by period in the air. Thanks to low weight, UAVs do not require strong thermals, which allows flying almost all over the world.

Researchers generally focus on increasing the battery capacity or the performance of the UAV. However, this study’s concentration is to increase the flight duration of the UAV by using geographical currents. For this purpose, taking advantage of bird morphology is quite a new topic. Also, glider type designs are rarely found in the field.