Using the Kalman Filter for Auto Bit-rate H.264 Streaming Based on Human Interaction

2013 ◽  
Vol 9 (4) ◽  
pp. 58-74
Author(s):  
Wei-Tsong Lee ◽  
Tin-Yu Wu ◽  
Yu-Chieh Cheng ◽  
Yue-Ru Chuang ◽  
Shiann-Tsong Sheu
Keyword(s):  
Kalman Filter ◽  
Video Quality ◽  
Interactive Systems ◽  
Human Interaction ◽  
Experimental Result ◽  
Interactive System ◽  
Rate Variation ◽  
Bit Rate ◽  
Audio Data

Human Machine Interface (HMI) and interactive systems applications are complex and diversified but human machine interaction in networks is even more complex. To design an interactive system, the designers must consider factors including design, technologies, people, activities and contexts. As the intermediary for human and machines, the interactive system takes charge of not only data transmission, display, storage and convertion, but also reactions to human behaviors. Based on human interaction, this paper focuses on the popular video streaming. As one of the most commonly used compression video formats, H.264 provides better quality at lower bit-rates than its previous standards in transmitting video/audio data. However, the quality of networked multimedia streaming easily fluctuates with the bit-rate variation. In order to maintain good video quality, this paper proposes to use the Kalman filter to implement the Auto bit-rate technique, which can regulate the bit-rate of the video/audio data automatically when the bit-rate is insufficient, and simultaneously guarantee the video quality. The experimental result proves that our proposed Auto bit-rate scheme can regulate the bit-rate to achieve the optimal visual quality and offer the best quality of service at the same time.

scholarly journals Evaluation of UMTS RLC Parameters for MPEG-4 Video Streaming

1970 ◽  
Vol 3 (1) ◽  
pp. 56-62
Author(s):  
Arisa Panchaem ◽  
Sinchai Kamolpiwong ◽  
Mallika Unhawiwat ◽  
Suthon Saewong
Keyword(s):  
Video Quality ◽  
Video Stream ◽  
Radio Link ◽  
Bit Rate ◽  
Mobile Telecommunication ◽  
Transmission Errors ◽  
Code Division Multiple ◽  
3G Mobile Phone ◽  
Link Layer Protocol

Universal Mobile Telecommunication Systems (UMTS) known as Third Generation (3G) mobile phone systems using Wideband Code Division Multiple Access (WCDMA) standard aim to provide a high bit rate of services to enable a high quality of multimedia communications. The 3G specification entity, 3GPP, has defined a reliable link layer protocol, Radio Link Control (RLC), for hiding transmission errors from upper layers. Due to the complexity of the protocol and the a number of parameter configurations available, there are many ways that can degrade a system performance, such as incorrect parameters configuration, buffer missmanagement, protocol stalling, etc. MPEG-4 is widely used for video stream services due to its good video quality at low bit rate. In this paper, we have studied on the impacts of RLC parameters, especially RLC timer and polling mechanism, for MPEG-4 video stream transmission by using a computer simulation. Our simulation results provide some suggestions value to optimize such parameters, e.g. RLC time and polling.

Mosaicing of Acoustic Video Images for Underwater Structure Inspection

2010 ◽  
Author(s):  
Jianfeng Tong ◽  
Jun Han ◽  
Wei Shen ◽  
Panlin Xu
Keyword(s):  
Video Quality ◽  
Experimental Result ◽  
Turbid Water ◽  
Dual Frequency ◽  
Applied Physics ◽  
Optical Images ◽  
Underwater Structure ◽  
Sequential Images ◽  
Underwater Structures

With the development of international communication and the advent of terrorism, safety and security of the underwater structures such as shipping dock, bridge pier and the bottom of ship hull become a key issue. Generally, in order to inspect the underwater structures, divers are sent down to make tactile examination, or with a camera to take photos or video tapes for further study and examination. However, in dark, turbid water, the quality of the optical images is practically not good enough to give much useful information of the underwater structures. And the working efficiency of this kind of inspection is relatively low. To overcome these problems, it is imperative that more efficient and effective inspection methods are developed. Recently, an acoustic lens camera called DIDSON (Dual-frequency Identification Sonar), which is invented by the Applied Physics Laboratory, University of Washington, can provide almost-video-quality images to identify objects even in turbid water. It has been proved to be very useful in underwater objects searching, especially in dark, turbid water. Although the quality of every single frame provided by DIDSON is quite good, its field of view is narrow, only 29 degrees in horizontal and 14 degrees in vertical, making it hard to comprehend the overall condition of the inspection area and guarantee the safety and security of underwater structures. In this paper, we present a new mosaicing method for the time-sequential images provided by DIDSON, which enables us to inspect the whole underwater structure in a computer screen. An experiment was carried out to inspect the underwater part of a shipping dork. Our experimental result has shown that the proposed method can successfully mosaic the images provided by DIDSON, and thereby expand the visual field of DIDON indirectly which enables it to be effectively used in underwater structures inspection.

Co-refining Interactive Systems with Older Adults from Function, Form and Interaction

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Kai KANG ◽  
Jun HU ◽  
Bart HENGEVELD ◽  
Frens JOEP ◽  
Caroline HUMMELS
Keyword(s):  
Older Adults ◽  
Participatory Design ◽  
Interactive Systems ◽  
Interactive System ◽  
Mutual Understanding ◽  
Preliminary Design ◽  
Function Form ◽  
Phase Design

Designing interactive systems that are pragmatic, attractive and easy to use for older adults is challenging. Participatory design, as an approach to enhance the mutual understanding between designers and end users, has been proved to be useful to improve the quality of design for older people. However, PD research has long been criticized for extensively dealing with the early-phase design while putting less emphasis on the later stages. In this paper, we argue for the importance of collaborative refinement when designing interactive systems for older adults. Through a case study, we describe our experience of co-refining the preliminary design of an interactive system with older participants from three perspectives: function, form and interaction. We also explored to adopt some potential PD methods and conclude by discussing the effectiveness of the chosen approach and methods.

Pengaruh Jenis Co-Solvent terhadap Rendemen dan Mutu Biodiesel secara Transesterifikasi In Situ Menggunakan Radiasi Gelombang Mikro

2016 ◽  
Vol 10 (2) ◽  
pp. 119-126
Author(s):  
Mahlinda Mahlinda ◽  
Fitriana Djafar
Keyword(s):  
Catalyst Concentration ◽  
Maximum Yield ◽  
Acid Value ◽  
Experimental Result ◽  
In Situ Transesterification ◽  
Yield And Quality ◽  
Solvent Type ◽  
Biodiesel Quality

The main purpose of this research was to observer effect co-solvent type (n-Hexane, chloroform and without co-solvent)  toward yield and quality of biodiesel via in situ transesterification process using microwave irradiation. The process was studied at microwave power 450 watt, reaction time 4 minutes, methanol to seed ratio 25:1 and catalyst concentration 5%. The physicochemical parameters of the biodiesel produced such as viscosity, density and acid value were analysed and compared with the SNI 7182-2012 standard. The experimental result showed the maximum yield biodiesel 78,32% obtained by using co-solvent chloroform.Test result of physicochemical properties (viscosity, density and acid value) of biodiesel products using co solvent n-Hexane, chloroform and without co solvent showed that these products conform to the SNI 7182-2012 standars. The type of co-solvent only affectedon biodiesel yield dan not affected on biodiesel quality (viscosity, density and acid value).  ABSTRAKTujuan penelitian ini adalah untuk mempelajari pengaruh jenis co-solvent (n-Hexane, chloroform dan tanpa co-solvent) terhadap rendemen dan mutu biodiesel secara trasesterifikasi in situ menggunakan radiasi gelombang mikro. Proses dilakukan pada daya gelombang mikro 450 watt, waktu reaksi 4 menit, perbandingan berat metanol terhadap bahan baku 25:1 dan jumlah katalis 5%. Parameter fisiko kimia dari produk biodiesel seperti viskositas, densitas dan angka asam di analisa dan dibandingkan dengan standar SNI 7182-2012 tentang biodiesel. Hasil penelitian menunjukkan rendemen maksimum biodiesel sebesar 78,32% diperoleh dengan menggunakan co-solvent chloroform. Hasil pengujian  karakteristik fisiko kimia (viskositas, densitas dan angka asam) dari produk biodiesel menggunakan co-solvent n-Hexane, chloroform dan tanpa co-solvent menunjukkan bahwa semua parameter ini masih memenuhi standar SNI 1782-2012 tentang biodiesel. Jenis co-solvent hanya berpengaruh pada rendemen biodiesel dan tidak berpengaruh terhadap mutu biodiesel (viskositas, densitas dan bilangan asam).Kata kunci: co-solvent, in situ transesterifikasi, microwave, rendemen, mutu   

MSHE-PWM Control of Modular Multilevel Direct Current Transmission System

2015 ◽  
Vol 9 (1) ◽  
pp. 553-559
Author(s):  
HU Xin-xin ◽  
Chen Chun-lan
Keyword(s):  
Pulse Width Modulation ◽  
Reactive Power ◽  
Balance Control ◽  
Electric Energy ◽  
Access Point ◽  
Experimental Result ◽  
Switching Frequency ◽  
Pwm Control ◽  
Harmonic Elimination

In order to optimize the electric energy quality of HVDC access point, a modular multilevel selective harmonic elimination pulse-width modulation (MSHE-PWM) method is proposed. On the basis of keeping the minimum action frequency of the power device, MSHE-PWM method can meet the requirement for accurately eliminating low-order harmonics in the output PWM waveform. Firstly, establish the basic mathematical model of MMC topology and point out the voltage balance control principle of single modules; then, analyze offline gaining principle and realization way of MSHEPWM switching angle; finally, verify MSHE-PWM control performance on the basis of MMC reactive power compensation experimental prototype. The experimental result shows that the proposed MSHE-PWM method can meet such performance indexes as low switching frequency and no lower-order harmonics, and has verified the feasibility and effectiveness thereof for optimizing the electric energy quality of HVDC access point.

Evaluation of the Quality, Educational Value and Utility of the Videos on YouTube for Laparoscopic Low Anterior Resection

2021 ◽  
pp. 000313482110111
Author(s):  
Erol Piskin ◽  
Muhammet Kadri Çolakoğlu ◽  
Ali Bal ◽  
Volkan Oter ◽  
Erdal Birol Bostanci
Keyword(s):  
Anterior Resection ◽  
Low Anterior Resection ◽  
Video Quality ◽  
Relevant Information ◽  
Teaching Quality ◽  
Educational Value ◽  
Laparoscopic Low Anterior Resection ◽  
Significant Difference ◽  
October 17

Background Minimally invasive surgery is a rising trend in colorectal surgery and is on its way to becoming the gold standard due to the benefits it provides for patients. This study aims to test the efficacy for educational purposes by evaluating the videos published on YouTube ( www.youtube.com ) channel for low anterior resection procedure in rectum surgery. Methods We searched YouTube on October 17, 2020 to choose video clips that included relevant information about laparoscopic low anterior resection (LAR) for rectal cancer. Results We included 25 academics and 75 individual videos in this study. The teaching quality of the videos was evaluated according to academic and individual videos, and it was seen that the teaching quality scores of academic videos were higher and this result was statistically significant ( P = .03). The modified Laparoscopic Surgery Video Educational Guidelines (LAP-VEGaS) criteria were found that the score was higher in individual videos ( P = .014). The median Video Power Index (VPI) value was 1.50 (range .05-347) and the mean ratio was 7.01 ± 3.52. There was no statistically significant difference between the 2 groups ( P = .443). Discussion Video-based surgical learning is an effective method for surgical education. Our study showed that the video quality and educational content of most of the videos about the low anterior resection procedure on YouTube were low. The videos of academic origin seem more valuable than individual videos. As far as video popularity is concerned, YouTube viewers are not selective. For this reason, training videos to be used for educational purposes must be passed through a standardized evaluation filter.

scholarly journals Producing ‘good enough’ automated transcripts securely: Extending Bokhove and Downey (2018) to address security concerns

2021 ◽  
Vol 14 (1) ◽  
pp. 205979912098776
Author(s):  
Joseph Da Silva
Keyword(s):  
Cyber Security ◽  
English Language ◽  
Negative Impact ◽  
Early Career ◽  
Third Party ◽  
Doctoral Research ◽  
Computing Services ◽  
Cloud Computing Services ◽  
Audio Data

Interviews are an established research method across multiple disciplines. Such interviews are typically transcribed orthographically in order to facilitate analysis. Many novice qualitative researchers’ experiences of manual transcription are that it is tedious and time-consuming, although it is generally accepted within much of the literature that quality of analysis is improved through researchers performing this task themselves. This is despite the potential for the exhausting nature of bulk transcription to conversely have a negative impact upon quality. Other researchers have explored the use of automated methods to ease the task of transcription, more recently using cloud-computing services, but such services present challenges to ensuring confidentiality and privacy of data. In the field of cyber-security, these are particularly concerning; however, any researcher dealing with confidential participant speech should also be uneasy with third-party access to such data. As a result, researchers, particularly early-career researchers and students, may find themselves with no option other than manual transcription. This article presents a secure and effective alternative, building on prior work published in this journal, to present a method that significantly reduced, by more than half, interview transcription time for the researcher yet maintained security of audio data. It presents a comparison between this method and a fully manual method, drawing on data from 10 interviews conducted as part of my doctoral research. The method presented requires an investment in specific equipment which currently only supports the English language.

Flight performance monitoring with optimal filtering applications

2019 ◽  
Vol 124 (1272) ◽  
pp. 170-188
Author(s):  
V. A. Deo ◽  
F. Silvestre ◽  
M. Morales
Keyword(s):  
Kalman Filter ◽  
Performance Monitoring ◽  
The Body ◽  
Flight Performance ◽  
Performance Parameters ◽  
Sideslip Angle ◽  
Fuel Flow ◽  
Aircraft Performance ◽  
Lift And Drag

ABSTRACTThis work presents an alternative methodology for monitoring flight performance during airline operations using the available inboard instrumentation system. This method tries to reduce the disadvantages of the traditional specific range monitoring technique where instrumentation noise and cruise stabilisation conditions affect the quality of the performance monitoring results. The proposed method consists of using an unscented Kalman filter for aircraft performance identification using Newton’s flight dynamic equations in the body X, Y and Z axis. The use of the filtering technique reduces the effect of instrumentation and process noise, enhancing the reliability of the performance results. Besides the better quality of the monitoring process, using the proposed technique, additional results that are not possible to predict with the specific range method are identified during the filtering process. An example of these possible filtered results that show the advantages of this proposed methodology are the aircraft fuel flow offsets, as predicted in the specific range method, but also other important aircraft performance parameters as the aircraft lift and drag coefficients (CL and CD), sideslip angle (β) and wind speeds, giving the operator a deeper understanding of its aircraft operational status and the possibility to link the operational monitoring results to aircraft maintenance scheduling. This work brings a cruise stabilisation example where the selected performance monitoring parameters such as fuel flow factors, lift and drag bias, winds and sideslip angle are identified using only the inboard instrumentation such as the GPS/inertial sensors, a calibrated anemometric system and the angle-of-attack vanes relating each flight condition to a specific aircraft performance monitoring result. The results show that the proposed method captures the performance parameters by the use of the Kalman filter without the need of a strict stabilisation phase as it is recommended in the traditional specific range method, giving operators better flexibility when analysing and monitoring fleet performance.

scholarly journals Adaptive Reservation of Network Resources According to Video Classification Scenes

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 1949
Author(s):  
Lukas Sevcik ◽  
Miroslav Voznak
Keyword(s):  
User Satisfaction ◽  
Quality Evaluation ◽  
Spatial Information ◽  
Service Providers ◽  
Video Quality ◽  
Subjective Assessment ◽  
Video Sequences ◽  
Network Resources ◽  
Proposed Model

Video quality evaluation needs a combined approach that includes subjective and objective metrics, testing, and monitoring of the network. This paper deals with the novel approach of mapping quality of service (QoS) to quality of experience (QoE) using QoE metrics to determine user satisfaction limits, and applying QoS tools to provide the minimum QoE expected by users. Our aim was to connect objective estimations of video quality with the subjective estimations. A comprehensive tool for the estimation of the subjective evaluation is proposed. This new idea is based on the evaluation and marking of video sequences using the sentinel flag derived from spatial information (SI) and temporal information (TI) in individual video frames. The authors of this paper created a video database for quality evaluation, and derived SI and TI from each video sequence for classifying the scenes. Video scenes from the database were evaluated by objective and subjective assessment. Based on the results, a new model for prediction of subjective quality is defined and presented in this paper. This quality is predicted using an artificial neural network based on the objective evaluation and the type of video sequences defined by qualitative parameters such as resolution, compression standard, and bitstream. Furthermore, the authors created an optimum mapping function to define the threshold for the variable bitrate setting based on the flag in the video, determining the type of scene in the proposed model. This function allows one to allocate a bitrate dynamically for a particular segment of the scene and maintains the desired quality. Our proposed model can help video service providers with the increasing the comfort of the end users. The variable bitstream ensures consistent video quality and customer satisfaction, while network resources are used effectively. The proposed model can also predict the appropriate bitrate based on the required quality of video sequences, defined using either objective or subjective assessment.

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