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The purpose of this paper is to increase flight performance of small unmanned aerial vehicle (UAV) using simultaneous UAV and autopilot system design.

A small UAV is manufactured in Erciyes University, College of Aviation, Model Aircraft Laboratory. Its wing and tail is able to move forward and backward in the nose-to-tail direction in prescribed interval. Autopilot parameters and assembly position of wing and tail to fuselage are simultaneously designed to maximize flight performance using a stochastic optimization method. Results are obtained are used for simulations.

Using simultaneous UAV and autopilot system design idea, flight performance is maximized.

Permission of Directorate General of Civil Aviation in Turkey is required for testing UAVs in long range.

Simultaneous design idea is very beneficial for improving UAV flight performance.

Creating a novel method to improve flight performance of UAV and developing an algorithm performing simultaneous design idea.

Information retrieval (IR) and feedback in Extensible Markup Language (XML) are rather new fields for researchers; natural questions arise, such as: how good are the feedback algorithms in XML IR? Can they be evaluated with standard evaluation tools? Even though some evaluation methods have been proposed in the literature it is still not clear yet which of them are applicable in the context of XML IR, and which metrics they can be combined with to assess the quality of XML retrieval algorithms that use feedback. This paper aims to elaborate on this.

The efficient evaluation of relevance feedback (RF) algorithms for XML collection posed interesting challenges on the IR and database researchers. The system based on the keyword‐based queries whether on the main query or in the RF processing instead of the XPath and structure query languages which were more complex. For measuring the efficiency of the system, the paper used the extended RF algorithms (residual collection and freezeTop) for evaluating the performance of the XML search engines. Compared to previous approaches, the paper aimed at removing the effect of the results for which the system has knowledge about their relevance, and at measuring the improvement on unseen relevant elements. The paper implemented the proposed evaluation methodologies by extending a standard evaluation tool with a module capable of assessing feedback algorithms for a specific set of metrics.

In this paper, the authors create an efficient XML retrieval system that is based on a query refinement by making a feedback processing and extending the main query terms with new terms mostly related to the main terms.

The authors are working on more efficient retrieval algorithms to get the top‐ten results related to the submitted query. Moreover, they plan to extend the system to handle complex XPath expression.

This paper presents an efficient evaluation of RF algorithms for XML collection retrieval system.

Effective information management can help real estate operators improve asset performance during use, reducing environmental impact. The purpose of this exploratory study is to identify and prioritise key drivers, challenges and opportunities relating to information management, from the point of view of a diverse cohort of facilities practitioners, with the aim of guiding future research direction and contributing to a comprehensive domain understanding.

Nine interviews are conducted across a broad sample of real estate sectors, the respondents including six facility managers and three data managers. A thematic analysis results in the identification and ranking in terms of importance of 44 emergent themes. These themes are then grouped into abstracted categories for analysis and synthesis.

This study indicates that systemic rather than technical issues are the greatest barrier to effective information management for facilities practitioners, the interviews providing examples of practical measures which address these challenges, promoting lifecycle thinking. Alignment is also found between the facilities and data management cohorts regarding lifecycle thinking towards both physical assets and information.

This study provides direction for future developments in the facilities sector, suggesting the pursuit to address systemic issues as being both worthwhile and feasible.

The novelty of this study is the ranking and synthesis of practitioner priorities with regard to high-level information management issues which is lacking in the literature, with a focus to-date on case-specific technical integration.

This paper aims to analyze and investigate the performance of an improved fault detection and identification (FDI) method based on multiple criteria, applied to six-switch three-phase inverter (SSTPI)-fed induction motor (IM) drives under both single and multiple open insulated-gate bipolar transistors(IGBT) faults.

This paper proposes an advanced diagnostic method for both single and multiple open IGBT faults dedicated to SSTPI-fed IM drives considering five distinct faulty operating conditions as follows: a single IGBT open-circuit fault, a single-phase open-circuit fault, a non-crossed double fault in two different legs, a crossed double fault in two different legs and a three-IGBT open-circuit fault. This is achieved because of the introduction of a new diagnosis variable provided using the information of the slope of the current vector in (α-β) frame. The proposed FDI method is based on the synthesis and the analysis, under both healthy and faulty operations, of the behaviors of the introduced diagnosis variable, the three motor phase currents and their normalized average values. Doing so, the developed FDI method allows a best compromise of fast detection and precision localization of IGBT open-circuit fault of the inverter.

Simulation works, carried out considering the implementation of the direct rotor flux oriented control in an IM fed by the conventional SSTPI, have proved the high performance of the advanced FDI method in terms of fast fault detection associated with a high robustness against false alarms, against speed and load torque fast variations and against the oscillations of the DC-bus voltage in the case of both healthy and faulty operations.

This work should be extended considering the validation of the obtained simulation results through experiments.

Different from other FDI methods, which suffer from a low diagnostic effectiveness for low load levels and false alarms during transient operation, this method offers the potentialities to overcome these drawbacks because of the introduction of the new diagnosis variable. This latter, combined with the information provided from the three motor phase currents and their normalized average values allow a more efficient detection and identification of IGBT open-circuit fault.

The purpose of this paper is to analyze cloud reviews according to the end-user context and requirements.

propose a comprehensive knowledge base composed of interconnected Web Ontology Language, namely, modular ontology for cloud service opinion analysis (SOPA). The SOPA knowledge base will be the basis of context-aware cloud service analysis using consumers' reviews. Moreover, the authors provide a framework to evaluate cloud services based on consumers' reviews opinions.

The findings show that there is a positive impact of personalizing the cloud service analysis by considering the reviewers' contexts in the performance of the framework. The authors also proved that the SOPA-based framework outperforms the available cloud review sites in term of precision, recall and F-measure.

Limited information has been provided in the semantic web literature about the relationships between the different domains and the details on how that can be used to evaluate cloud service through consumer reviews and latent opinions. Furthermore, existing approaches are lacking lightweight and modular mechanisms which can be utilized to effectively exploit information existing in social media.

The SOPA-based framework facilitates the opinion based service evaluation through a large number of consumer's reviews and assists the end-users in analyzing services as per their requirements and their own context.

The SOPA ontology is capable of representing the content of a product/service as well as its related opinions, which are extracted from the customer's reviews written in a specific context. Furthermore, the SOPA-based framework facilitates the opinion based service evaluation through a large number of consumer's reviews and assists the end-users in analyzing services as per their requirements and their own context.

The purpose of this paper is to introduce a novel intensity-modulated fiber optic sensor for real-time intrusion detection using a fiber-optic microbend sensor and an optical time-domain reflectometer (OTDR).

The proposed system is tested using different scenarios using person/car as intruders. Experiments are conducted in the lab and in the field. In the beginning, the OTDR trace is obtained and recorded as a reference signal without intrusion events. The second step is to capture the OTDR trace with intrusion events in one or multiple sectors. This measured signal is then compared to the reference signal and processed by matrix laboratory to determine the intruded sector. Information of the intrusion is displayed on an interactive screen implemented by Visual basic. The deformer is designed and implemented using SOLIDWORKS three-dimensional computer aided design Software.

The system is tested for intrusions by performing two experiments. The first experiment is performed for both persons (>50 kg) in the lab and cars in an open field with a car moving at 60 km/h using two optical fiber sectors of lengths 200 and 500 m. For test purposes, the deformer length used in the experiment is 2 m. The used signal processing technique in the first experiment has some limitations and its accuracy is 70% after measuring and recording 100 observations. To overcome these limitations, a second experiment with another technique of signal processing is performed.

The system can perfectly display consecutive intrusions of the sectors, but in case of simultaneous intrusions of different sectors, which is difficult to take place in real situations, there will be the ambiguity of the number of intruders and the intruded sector. This will be addressed in future work. Suitable and stable laser power is required to get a suitable level of backscattered power. Optimization of the deformer is required to enhance the sensitivity and reliability of the sensor.

The proposed work enables us to benefit from the ease of implementation and the reduced cost of the intensity-modulated fiber optic sensors because it overcomes the constraints that prevent using the intensity-modulated fiber optic sensors for intrusion detection.

The proposed system is the first time long-range intensity-modulated fiber optic sensor for intrusion detection.

The purpose of this paper is to rise the autonomous flight performance of the small unmanned aerial vehicle (UAV) using simultaneous tailplane of UAV and autopilot system design.

A small UAV is remanufactured in the UAV laboratory. Its tailplane can be changed before the flight. Autopilot parameters and some parameters of tailplane are instantaneously designed to maximize autonomous flight performance using a stochastic optimization method. Results found are applied for simulations.

Benefitting simultaneous tailplane of UAV and autopilot system design process, autonomous flight performance is maximized.

Authorization of Directorate General of Civil Aviation in Turkey is required for UAV flights.

Simultaneous tailplane and autopilot system design process is so useful for refining UAV autonomous flight performance.

Simultaneous tailplane and autopilot system design process fulfills confidence, high autonomous performance, and easy service demands of UAV users. By that way, UAV users will be able to use better UAVs.

Creating a novel technique to recover autonomous flight performance (e.g. less overshoot, less settling time and less rise time during trajectory tracking) of UAV and developing a novel procedure performing simultaneous tailplane of UAV and autopilot system design idea.

The purpose of this paper is to study a solar thermal system. Solar chimney power plants (SCPPs) produce electrical energy and thermal heat from solar radiation. The thermal study of SCPPs is required, as these solar systems are characterized by high costs.

This study presents a numerical study of unsteady airflow characteristics inside an SCPP. In fact, the generated power of the SCPP depends on environmental conditions. To validate this study, a solar prototype is built in the National School of Engineers of Sfax, University of Sfax, Tunisia, North Africa. The system is mainly composed by a collector, an absorber, a chimney and a turbine. The collector diameter is 2750 mm, the collector roof height is 50 mm, the chimney height is 3,000 mm and the turbine diameter is 150 mm.

The local characteristics of the air flow are presented and analyzed, such as the distribution of the temperature, the magnitude velocity and the total pressure. Analysis confirms that ambient air temperature and solar radiation are important environmental variables for the improvement of solar chimney efficiency.

Although much work has been done to date, it has been noted that the most published works have presented the profiles of air velocity and air temperature in a specific position within the solar setup. However, these profiles could sometimes be misinterpreted. In fact, some researchers did not focus on the distribution of air temperature, air velocity and pressure. These parameters are important to optimize the solar system. Indeed, the most published works deal with a larger prototype, such as the Manzanares prototype. However, it has not found connections between larger and small prototypes of SCPP.

The purpose of this paper is to improve autonomous flight performance of an unmanned aerial vehicle (UAV) having actively sweep angle morphing wing using simultaneous UAV and flight control system (FCS) design.

An UAV is remanufactured in the ISTE Unmanned Aerial Vehicle Laboratory. Its wing sweep angle can vary actively during flight. FCS parameters and wing sweep angle are simultaneously designed to optimize autonomous flight performance index using a stochastic optimization method called as simultaneous perturbation stochastic approximation (SPSA). Results obtained are applied for flight simulations.

Using simultaneous design process of an UAV having actively sweep angle morphing wing and FCS design, autonomous flight performance index is maximized.

Authorization of Directorate General of Civil Aviation in Turkey is crucial for real-time UAV flights.

Simultaneous UAV having actively sweep angle morphing wing and FCS design process is so beneficial for recovering UAV autonomous flight performance index.

Simultaneous UAV having actively sweep angle morphing wing and FCS design process achieves confidence, high autonomous performance index and simple service demands of UAV operators.

Composing a novel approach to improve autonomous flight performance index (e.g. less settling and rise time, less overshoot meanwhile trajectory tracking) of an UAV and creating an original procedure carrying out simultaneous UAV having actively sweep angle morphing wing and FCS design idea.