Real-time Performance Assessment Research Articles

Experimental and model based performance investigation of a solid desiccant wheel dehumidifier in subtropical climate

This paper presents real time performance analysis of a silica gel based desiccant wheel dehumidifier. Thermodynamic model is also validated through comparison under a wide range of operating conditions for subtropical climate conditions. Initially, a mathematical model is developed by using various set of equations for desiccant wheel dehumidifier in engineering equation solver. After-wards, a parametric analysis of the system is performed including various design and climate parameters such as: inlet air humidity ratio, inlet air temperature, regeneration inlet humidity ratio, regeneration temperature, and rotation speed of the wheel. Then, an experimental set-up of the system is established in Taxila Pakistan for the real-time performance assessment. The results revealed that the optimal rotation speed of desiccant wheel ranged from 15-17 rph. The maximum model based and experimental effectiveness is 0.45 and 0.43, respectively at re-generation temperature of 80°C. The maximum and minimum root mean square error values for effectiveness are 3.2% and 2.1%, respectively. Thus, the comparison between experimental and model results showed a good agreement.

Development of an EMG-based exergaming system for isometric muscle training and its effectiveness to enhance motivation, performance and muscle strength

Abstract Isometric exercises can be used for general strength conditioning or rehabilitation. To maximize their benefits without excess muscle fatigue, such exercises must be performed under medical prescription, which also needs to specify their intensity and duration. However, at home or at a clinic they are rarely real-time monitored or evaluated, which may delay or prevent goal achievement, with negative influence on participants’ motivation. Therefore, in this paper, it is introduced the development and clinical evaluation of an exergaming platform based on ElectroMyoGraphy (EMG) for the real-time monitoring and performance assessment of personalized isometric exercises. The system enables medical personnel to create personalized exergame sessions that oversee in real time the behavior of the main character in a game, based on the muscle force of the user, estimated from an EMG signal. In addition, it evaluates exercise performance, in terms of muscle contraction duration and relative effort during work and rest intervals. A data storage capability enables users to upload results in a cloud database, which can be accessed remotely by healthcare providers through an application. The system operates firstly by obtaining an EMG-force model for isometric contractions of the flexor digitorum superficialis muscle, which was then integrated in the exergaming platform. Then, a 4-week randomized controlled clinical trial was conducted with tailored isometric handgrip exercises using the proposed system versus conventional handgrip exercises to assess motivation and grip strength in patients with distal radius fracture. Exercise performance and subjective workload ratings were additionally evaluated. Results notably show that handgrip exercises with the proposed system yield an improvement in grip strength of 40.2% over conventional handgrip exercises, while experiencing higher motivation levels, contrasting with lower frustration and mental demand levels. However, continued research is ongoing to generalize the findings of the clinical trial to a larger patient population.

Real-time performance assessment and adaptive control for a water chiller unit in an HVAC system

The paper proposes an adaptive control method for a water chiller unit in a HVAC system. Based on the minimum variance evaluation, the adaptive control method was used to realize better control of the water chiller unit. To verify the performance of the adaptive control method, the proposed method was compared with an a conventional PID controller, the simulation results showed that adaptive control method had superior control performance to that of the conventional PID controller.

Digital platform for Sigma-Delta accelerometer assessment and test

A digital platform for fast assessment and testing of multiple order architectures of electromechanical Sigma-Delta modulators for MEMS capacitive accelerometers is introduced in this paper. It is well known that the introduction of a negative feedback loop on sensors presents significant advantages to improve important characteristics, such as precision, linearity, speed, and dynamic range over open-loop operation (Borovic et al. in J Micromech Microeng 15(10):1917–1924, 2005; Chen et al. in IEEE Sens J 16(17):6476–6495, 2016). In a closed-loop system, the controller is responsible for the aforementioned improvements, enabling the relaxation on the manufactured device specifications. Consequently, it demands better and more complex electronic circuits for the controller. A configurable multi-order (2nd, 3rd, 4th and 5th) ΣΔ module was developed in field-programmable gate array, along with the necessary signal acquisition and actuation modules, using a processor-centric approach, ensuring real-time performance, simple reconfiguration, and fast assessment of different orders and gains for the ΣΔ modulator with real MEMS devices. The system is capable of a measuring cycle lower than 100 ms. The platform was used to perform a comparison between two different types of MEMS accelerometers, evaluating the results obtained with second, third, fourth and fifth modulation orders for two bandwidth values—200 and 1000 Hz. The best noise figure achieved was 4.4 µg/√Hz, using a fifth order ΣΔ modulator and the device with the larger seismic mass. A comparison between three similar devices is also performed, as well as a comparison between simulated and experimental results.

Effect of hole-transporting materials on the photovoltaic performance and stability of all-ambient-processed perovskite solar cells

High-efficiency perovskite solar cells (PSCs) reported hitherto have been mostly prepared in a moisture and oxygen-free glove-box atmosphere, which hampers upscaling and real-time performance assessment of this exciting photovoltaic technology. In this work, we have systematically studied the feasibility of all-ambient-processing of PSCs and evaluated their photovoltaic performance. It has been shown that phase-pure crystalline tetragonal MAPbI3 perovskite films are instantly formed in ambient air at room temperature by a two-step spin coating process, undermining the need for dry atmosphere and post-annealing. All-ambient-processed PSCs with a configuration of FTO/TiO2/MAPbI3/Spiro-OMeTAD/Au achieve open-circuit voltage (990 mV) and short-circuit current density (20.31 mA/cm2) comparable to those of best reported glove-box processed devices. Nevertheless, device power conversion efficiency is still constrained at 5% by the unusually low fill-factor of 0.25. Dark current–voltage characteristics reveal poor conductivity of hole-transporting layer caused by lack of oxidized spiro-OMeTAD species, resulting in high series-resistance and decreased fill-factor. The study also establishes that the above limitations can be readily overcome by employing an inorganic p-type semiconductor, copper thiocyanate, as ambient-processable hole-transporting layer to yield a fill-factor of 0.54 and a power conversion efficiency of 7.19%. The present findings can have important implications in industrially viable fabrication of large-area PSCs.

Hospital performance management method and applications based on data monitoring and fine management

Scientific, accurate and real-time performance management and assessment prove key to hospital development. This paper, based on integration of various hospital operation systems, proposed to monitor medical service data in a horizontal way and manage the key sections and problems in a longitudinal way. The purpose is to extract and summarize such systems, and solve critical issues of contemporary hospital performance, effectively integrating performance data monitoring and performance management. Scientific, accurate, real-time, and fair performance evaluation can be thus achieved, ranging from data monitoring to business management and measurement of management outcomes based on data monitoring. Key words: Data monitoring; Fine management; Performance management; Performance data; Performance evaluation

A probabilistic framework for real-time performance assessment of inferential sensors

A definition for the reliability of inferential sensor predictions is provided. A data-driven Bayesian framework for real-time performance assessment of inferential sensors is proposed. The main focus is on characterizing the effect of operating space on the reliability of inferential sensor predictions. A holistic, quantitative measure of the reliability of the inferential sensor predictions is introduced. A methodology is provided to define objective prior probabilities over plausible classes of reliability based on the total misclassification cost. The real-time performance assessment of multi-model inferential sensors is also discussed. The application of the method does not depend on the identification techniques employed for model development. Furthermore, on-line implementation of the method is computationally efficient. The effectiveness of the method is demonstrated through simulation and industrial case studies.

Real-time Performance Assessment of Inferential Sensors

A data-driven Bayesian framework for real-time performance assessment of inferential sensors is proposed. The application of the proposed Bayesian solution does not depend on the identification techniques employed for inferential model development. The effectiveness of the proposed method is demonstrated through a simulation case study.

Probabilistic Fatigue Assessment Based on Bayesian Learning for Wind-Excited Long-Span Bridges Installed with WASHMS

For long-span bridges located in wind-prone regions, it is a trend to install in situ Wind and Structural Health Monitoring System (WASHMS) for long-term real-time performance assessment. One of the functions of the WASHMS is to provide information for the assessment of wind-induced fatigue damage. Considering the randomness of wind, it is more reasonable to describe wind-induced fatigue damage of bridge in a probabilistic way. This paper aims to establish a probabilistic fatigue model of fatigue damage based on Bayesian learning, and it is applied to a wind-excited long-span bridge installed with a WASHMS. Wind information recorded by the WASHMS is utilized to come up with the joint probability density function of wind speed and direction. A stochastic wind field and subsequently wind-induced forces are introduced into the health monitoring oriented finite element model (FEM) of the bridge to predict the statistics of stress responses in local bridge components. Bayesian learning approach is then applied to determine the probabilistic fatigue damage model. The Tsing Ma suspension bridge in Hong Kong and its WASHMS are finally utilized as a case study. It shows that the proposed approach is applicable for the probabilistic fatigue assessment of long-span bridges under random wind loadings.

An insight into real-time performance assessment of a building integrated photovoltaic (BIPV) installation in Bangalore (India)

Building integrated photovoltaic (BIPV) applications are gaining widespread popularity. The performance of any given BIPV system is dependent on prevalent meteorological factors, site conditions and system characteristics. Investigations pertaining to the performance assessment of photovoltaic (PV) systems are generally confined to either controlled environment-chambers or computer-based simulation studies. Such investigations fall short of providing a realistic insight into how a PV system actually performs real-time. Solar radiation and the PV cell temperature are amongst the most crucial parameters affecting PV output. The current paper deals with the real-time performance assessment of a recently commissioned 5.25kWp BIPV system installed at the Center for Sustainable Technologies, Indian Institute of Science, Bangalore. The overall average system efficiency was found to be 6% for the period May 2011–April 2012. This paper provides a critical appraisal of PV system performance based on ground realities, particularly characteristic to tropical (moderate) regions such as Bangalore, India.

Leveraging Educational Data Mining for Real-time Performance Assessment of Scientific Inquiry Skills within Microworlds

Leveraging Educational Data Mining for Real-time Performance Assessment of Scientific Inquiry Skills within Microworlds

Comparison of Alternative Real-Time Performance Measures for Measuring Signal Phase Utilization and Identifying Oversaturation

Various control algorithms process vehicle detector on and off times with the objective of quantifying split performance. Two such metrics are green occupancy ratio (GOR) and volume-to-capacity (v/c) ratio, both of which can be used to estimate the efficiency of a split as well as estimate oversaturated conditions. The GOR metric is attractive because of its simplicity of implementation; the v/c ratio is based on well-established traffic flow concepts and is independent of detector geometry although additional processing is required to develop the metric. Characterizing the impact of detection zone length and vehicle speed on the GOR as well as comparing its performance with another metric is important in understanding the robustness of GOR as a surrogate performance metric. This paper analyzes the difference between calculated GOR and v/c ratios over different detection zone lengths and differing vehicle speeds, compares these values with a calculated delay metric, and observes the effectiveness of GOR as an indicator of oversaturation. On the basis of the analysis, the paper documents the influence of approach speed and detection zone length on the calculated GOR metric. The paper concludes that the GOR values tend to reach a saturated value of 1.0 more rapidly than v/c, making it challenging for the analyst to identify oversaturated conditions by the metric alone. For practitioners using the GOR metric, it is critical that the system be calibrated properly because of the sensitivity of GOR to the detection zone length and vehicle speed. However, because direct measurement of v/c is difficult to obtain, GOR may still be a reasonable surrogate in real-time performance assessment of traffic signal systems.

Quality Monitoring of HIV-1-Infected and Uninfected Peripheral Blood Mononuclear Cell Samples in a Resource-Limited Setting

Human immunodeficiency virus type 1 (HIV-1) vaccine and natural history studies are critically dependent on the ability to isolate, cryopreserve, and thaw peripheral blood mononuclear cell (PBMC) samples with a high level of quality and reproducibility. Here we characterize the yield, viability, phenotype, and function of PBMC from HIV-1-infected and uninfected Ugandans and describe measures to ascertain reproducibility and sample quality at the sites that perform cryopreservation. We have developed a comprehensive internal quality control program to monitor processing, including components of method validation. Quality indicators for real-time performance assessment included the time from venipuncture to cryopreservation, time for PBMC processing, yield of PBMC from whole blood, and viability of the PBMC before cryopreservation. Immune phenotype analysis indicated lowered B-cell frequencies following processing and cryopreservation for both HIV-1-infected and uninfected subjects (P < 0.007), but all other major lymphocyte subsets were unchanged. Long-term cryopreservation did not impact function, as unstimulated specimens exhibited low background and all specimens responded to staphylococcal enterotoxin B (SEB) by gamma interferon and interleukin-2 production, as measured by intracellular cytokine staining. Samples stored for more than 3 years did not decay with regard to yield or viability, regardless of HIV-1 infection status. These results demonstrate that it is possible to achieve the high level of quality necessary for vaccine trials and natural history studies in a resource-limited setting and provide strategies for laboratories to monitor PBMC processing performance.

EHA-ESH Tutorials on Diagnostics in Hematological Malignancies: A Didactic Model for Training Programs in Hematology in Developing Countries

Tutorials are yearly diagnostic courses on Hematological Malignancies organized by the European School of Hematology (ESH) and the European Hematology Association (EHA), in close collaboration with the Catholic University of Rome and “La Sapienza” University of Rome, carried out from 2004 and accredited by the European Council for Accreditation in Hematology (ECAH). For the first 4 years, Tutorials were also supported by a grant from the Marie Curie EC action. The main innovative aspect is the use of technological support for interactive self-evaluation sessions, prepared by the speakers, with real-time performance assessment. For technical reasons, the number of participant in each Tutorial is limited to 100. Tutorial sessions are organized around three different didactical tools:nine sessions of formal lectures during which the speakers move from principles of blood cytomorphology in the different categories of hematology malignancies according to the WHO classification to the analysis of the usability of gene profiling in class discovery and class prediction,nine sessions of tutored clinical case presentations: the same speakers present two to three interactive clinical cases, each going through the diagnostic pathway with special attention to differential diagnosis, different treatment opportunities and patient follow-up. A detailed final case-comment is also provided for all cases together with an updated and specific list of references,five sessions of self-evaluation tests: for each session, four clinical cases are presented in a standard format of six multiple choice questions with a list of five possible answers for each question.Each trainee has a personal ID number to enable participation in the interactive tests by selecting one response to each question. At the end of the tests, results are anonymously and actively discussed with the authors. Speakers are leading European hematologists selected according to their specific competence in a specific field. The user appreciation and the validity of the didactic model is attested to by the worldwide participation: during these years, participants have come from 40 different countries from all five continents. EHA and ESH have been requested to duplicate these courses: the scientific material is organized on medial support and can be represented in other venues. From the year 2006, three Tutorials were successfully repeated in Brazil in association with the Escola Brasileira de Hematologia (the fourth is planned for October 2008). The organization of the repeated Tutorials (so called Type II Tutorials) is simpler than for the original ones: the local chair involves mainly local speakers for the lectures, while the didactic material (clinical cases and test cases) is the same as was used in the original Tutorial (Type I), with the support of just one or two faculty members from the original type I tutorial who have had experience in managing the didactic material.The organization of the courses is expensive and technically complex: the didactic material of each course is uploaded on an intranet platform connected with 25 PC stations (one for every four participants). For this reason, the Tutorial held in Paris in February 2008 was technically organized with a specially developed software connected to a Voting Boxes System (VBS), which is portable and allows the same course interactivity; this system will be used in forthcoming years. In addition, the VBS will easily permit the organization of Type II Tutorials for training programs in hematology in developing countries. This will represent one of the forthcoming didactic programs of EHA and ESH.

Autonomous bathymetry survey system

This paper describes the Autonomous Bathymetry Survey System (AutoSurvey), a system that provides automation of swath sonar bathymetric surveys. This system enables faster surveying of an area through environmentally adaptive techniques while ensuring adequate coverage and data quality. AutoSurvey assesses data quality and coverage in real time and generates next-trackline waypoints based on actual system performance. The need for real-time performance assessment is discussed. A primary factor considered is the effect of the environment on swath bathymetry system performance, which is difficult to predict a priori. The system's features, design, and implementation are discussed in this paper. Simulation and sea trial results are presented, as well as an analysis of the system's ability to reduce survey time.

The role of performance assessment in real time system management

This paper discusses paddy irrigation development in Malaysia in relation to real-time systems management and the role of performance assessment in such a system. The Muda Irrigation Scheme real-time management system is given as an illustration. This system has shown that, with performance assessment, managers are more prepared and able to respond quickly to issues faced in the day to day systems operations. In this system, demand-supply matching can be made faster and with improved utilisation of effective rainfall and uncontrolled flows. Opportunities for saving uncontrolled flows in the paddy fields can be identified in time. With dryseeding method, the system has been successful in sustaining production in severe water shortage situations. Into the 90s and beyond, no major infrastructure investments in irrigation systems are expected. Irrigation managers must be committed towards excellence in performance. This can be achieved through improved real-time performance assessment. Some aspects of performance assessment that could be improved are in its roles in meeting cropping intensity targets, accurate demand-supply matching, meeting water savings target and in alerting managers to potential crisis situations. Carefully designed and installed, performance assessment can also improve organisational and staff management.

Marine atmospheric effects on electro-optical systems performance

For the past 12 yr, a coordinated triservice effort has been under way in the U.S. Department of Defense to provide an atmospheric effects assessment capability for existing and planned electro-optical (EO) systems. This exploratory development effort by the U.S. Navy is reviewed. An initial marine aerosol model, the Navy Aerosol Model (NAM), which transitioned into LOWTRAN 6, and a more comprehensive model, the Navy Oceanic Vertical Aerosol Model (NOVAM), are discussed. In addition to marine aerosols and their extinction properties, accurate knowledge of marine background radiances and the effects of the intervening atmosphere are needed. Because <i>in situ</i> measurements of relevant environmental parameters are essential for real-time EO systems performance assessment and direct measurement of slant path extinction is most desirable, light detection and ranging (LIDAR) techniques are being developed. No technique, however, has yet emerged that is ready for shipboard implementation. A shipboard real-time performance assessment system, PREOS (performance and range for EO systems), has been developed and incorporated into the Navy's Tactical Environmental Support System (TESS), and improved target and background models are under development and will be incorporated into TESS when tested and validated. A reliable assessment capability can be used to develop tactical decision aids (TDAs), which permit optimum selection or combination of sensors and estimation of a ship's vulnerability against hostile systems.