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1
Al-Ali, A. R., M. T. Abuelma'atti, and A. Shabra. "An OTA-Based Digital-To-Analog Converter." Active and Passive Electronic Components 16, no. 3-4 (1994): 141–43. http://dx.doi.org/10.1155/1994/21258.
Повний текст джерелаАнотація:
A simple circuit for implementing a current-switching digital-to-analog converter is presented. The circuit uses operational transconductance amplifiers (OTAs) for switching a number of equal-value current sources. An R-2R ladder attenuator is used to scale the currents in a binary form. Experimental results show good performance.
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Toledo, Pedro, Paolo Crovetti, Hamilton Klimach, and Sergio Bampi. "Dynamic and Static Calibration of Ultra-Low-Voltage, Digital-Based Operational Transconductance Amplifiers." Electronics 9, no. 6 (June 12, 2020): 983. http://dx.doi.org/10.3390/electronics9060983.
Повний текст джерелаАнотація:
The calibration of the effects of process variations and device mismatch in Ultra Low Voltage (ULV) Digital-Based Operational Transconductance Amplifiers (DB-OTAs) is addressed in this paper. For this purpose, two dynamic calibration techniques, intended to dynamically vary the effective strength of critical gates by different modulation strategies, i.e., Digital Pulse Width Modulation (DPWM) and Dyadic Digital Pulse Modulation (DDPM), are explored and compared to classic static calibration. The effectiveness of the calibration approaches as a mean to recover acceptable performance in non-functional samples is verified by Monte-Carlo (MC) post-layout simulations performed on a 300 mV power supply, nW-power DB-OTA in 180 nm CMOS. Based on the same MC post-layout simulations, the impact of each calibration strategy on silicon area, power consumption, and OTA performance is discussed.
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Tekin, Ahmet Tezcan, and Ferhan Çebi. "Click and sales prediction for OTAs’ digital advertisements: Fuzzy clustering based approach." Journal of Intelligent & Fuzzy Systems 39, no. 5 (November 19, 2020): 6619–27. http://dx.doi.org/10.3233/jifs-189123.
Повний текст джерелаАнотація:
Within the most productive route, online travel agencies (OTAs) intend to use advanced digital media ads to expand their piece of the industry as a whole. The metasearch engine platforms are among the most consistently used digital media environments by OTAs. Most OTAs offer day by day deals in metasearch engine platforms that are paying per click for each hotel to get reservations. The administration of offering methodologies is critical along these lines to reduce costs and increase revenue for online travel agencies. In this study, we tried to predict both the number of impressions and the regular Click-Through-Rate (CTR) level of hotel advertising for each hotel and the daily sales amount. A significant commitment of our research is to use an extended dataset generated by integrating the most informative features implemented in various related studies as the rolling average for a different amount of day and shifted values for use in the proposed test stage for CTR, impression and sales prediction. The data is created in this study by one of Turkey’s largest OTA, and we are giving OTA’s a genuine application. The results at each prediction stage show that enriching the training data with the OTA-specific additional features, which are the most insightful and sliding window techniques, improves the prediction models ’ generalization capability, and tree-based boosting algorithms carry out the greatest results on this problem. Clustering the dataset according to its specifications also improves the results of the predictions.
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Palumbo, Gaetano, and Giuseppe Scotti. "A Novel Standard-Cell-Based Implementation of the Digital OTA Suitable for Automatic Place and Route." Journal of Low Power Electronics and Applications 11, no. 4 (October 28, 2021): 42. http://dx.doi.org/10.3390/jlpea11040042.
Повний текст джерелаАнотація:
This paper presents a novel implementation of a digital-based Operational Transconductance Amplifier (OTA) which has been recently introduced in the technical literature as a fully digital alternative to the conventional differential pair to implement low voltage analog amplifiers and comparators. The proposed implementation does not make use of resistors, floating gate resistors nor C-Muller elements and is made up of only digital gates usually available in the standard cell libraries. The resulting analog circuit schematic can be described using structural VHDL or Verilog languages and is suitable to be integrated in an automatic synthesis and place and route flow for digital circuits. The proposed digital-based amplifier has been implemented in a commercial 130 nm CMOS process by using an automatic place and route flow for layout generation starting from the Verilog netlist. Post layout simulations are presented to show the performance of the proposed circuit and compare it against the state of the art.
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Sebayang, Susy K., Desak Made Sintha Kurnia Dewi, Syifa’ul Lailiyah, and Abdillah Ahsan. "Mixed-methods evaluation of a ban on tobacco advertising and promotion in Banyuwangi District, Indonesia." Tobacco Control 28, no. 6 (October 19, 2018): 651–56. http://dx.doi.org/10.1136/tobaccocontrol-2018-054443.
Повний текст джерелаАнотація:
IntroductionTobacco advertisement bans in Indonesia are rare and seldom evaluated. The recent introduction of an outdoor tobacco advertisement (OTA) ban in Banyuwangi District, East Java, Indonesia provided an opportunity to evaluate such policy.MethodsUsing a mixed-methods approach, we undertook an observational study of OTA in 15 locations where such advertising had been prohibited. We also interviewed a sample of 114 store-owners/storekeepers and 131 community members, and conducted indepth interviews with government officials and the Public Order Agency (POA), the designated enforcement agency.ResultsIn phase 1 we found only one location was free of advertisements. We identified 667 advertisement points and 1283 advertisement materials in the study location; of these, 7% and 7.8% were within 25 m of schools and religious sites, respectively. Phase 2 showed that 68% of the respondents were unaware of the regulation, but many supported an OTA ban. Indepth interviews revealed that not all members of the POA were familiar with the regulation. POA members believed they will enforce the regulation better if higher level regulation for ban on tobacco advertisements, promotions and sponsorships was made and digital application is available to support surveillance.ConclusionPolicy violations were evident 1 year after the launch of OTA ban in Banyuwangi. Tobacco advertisements are still visible, including near schools and religious sites, potentially stimulating adolescents to smoke. Regional regulation and setting specific violation reductions as a performance indicator for POA could improve compliance. App-based technology could assist violation surveillance and reporting, as could awareness-raising campaigns that encouraged community support to report violation through the apps.
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Saputra, Yanu Ramdhani, Herlina Jayadianti, and Dyah Ayu Irawati. "Customer Loyalty Analysis On Online Travel Agent (OTA) Using American Customer Satisfaction Index (ACSI) And Structural Equation Modelling (SEM)." Telematika 19, no. 3 (October 31, 2022): 347. http://dx.doi.org/10.31315/telematika.v19i3.7734.
Повний текст джерелаАнотація:
Purpose: Knowing what affects customer loyalty in Online Travel Agent (OTA) Services. Which will help OTA Services to understand about customer satisfaction and customer loyalty so that they can develop their business in the future in order to get greater customer satisfaction and loyalty.Design/methodology/approach: Using the American Customer Satisfaction Index (ACSI) Model which explains the antecedents and consequences of customer satisfaction. In Antecedent there are variables of User Expectations, Perceived Quality, and Value benefits that have an impact on customer satisfaction variables then from causing customer complaints and customer loyalty. So that 9 research hypotheses are obtained based on the model used and tested using Structural Equation Modeling (SEM). Research requires data on respondents' answers distributed through digital media with a total need for 385 respondent data.Findings/result: After testing using SEM.The 9 hypotheses proposed show that 2 hypotheses are rejected and 7 hypotheses are accepted.Originality/value/state of the art: Previous research has been done but with different models and different methods.
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Marani, Roberto, and Anna Gina Perri. "A Review on the Study of Temperature Effects in the Design of A/D Circuits based on CNTFET." Current Nanoscience 15, no. 5 (July 19, 2019): 471–80. http://dx.doi.org/10.2174/1573413714666181009125058.
Повний текст джерелаАнотація:
In this paper, we review a procedure to study the effects of temperature in the design of A/D circuits based on CNTFETs. At first, we briefly describe a compact model, already proposed by us, in which the temperature variation in the drain current equation and in energy band gap is considered. Then, the effects of temperature variations in the design of analog circuits, such as a cascode current sink mirror and an Operational Transconductance Amplifier (OTA), and in the design of digital circuits including in particular NAND and NOR logic gates, are illustrated and widely discussed.
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Wang, Xiaoyu, Yue Li, Chao Yu, Wei Hong, and Anding Zhu. "Digital Predistortion of 5G Massive MIMO Wireless Transmitters Based on Indirect Identification of Power Amplifier Behavior With OTA Tests." IEEE Transactions on Microwave Theory and Techniques 68, no. 1 (January 2020): 316–28. http://dx.doi.org/10.1109/tmtt.2019.2944828.
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Dendouga, Abdelghani, Slimane Oussalah, Damien Thienpont, and Abdenour Lounis. "Multiobjective Genetic Algorithms Program for the Optimization of an OTA for Front-End Electronics." Advances in Electrical Engineering 2014 (August 13, 2014): 1–5. http://dx.doi.org/10.1155/2014/374741.
Повний текст джерелаАнотація:
The design of an interface to a specific sensor induces costs and design time mainly related to the analog part. So to reduce these costs, it should have been standardized like digital electronics. The aim of the present work is the elaboration of a method based on multiobjectives genetic algorithms (MOGAs) to allow automated synthesis of analog and mixed systems. This proposed methodology is used to find the optimal dimensional transistor parameters (length and width) in order to obtain operational amplifier performances for analog and mixed CMOS-(complementary metal oxide semiconductor-) based circuit applications. Six performances are considered in this study, direct current (DC) gain, unity-gain bandwidth (GBW), phase margin (PM), power consumption (P), area (A), and slew rate (SR). We used the Matlab optimization toolbox to implement the program. Also, by using variables obtained from genetic algorithms, the operational transconductance amplifier (OTA) is simulated by using Cadence Virtuoso Spectre circuit simulator in standard TSMC (Taiwan Semiconductor Manufacturing Company) RF 0.18 μm CMOS technology. A good agreement is observed between the program optimization and electric simulation.
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Agopian, Paula Ghedini Der, Joao A. Martino, Eddy Simoen, Rita Rooyackers, and Cor Claeys. "Tunnel-FET Evolution and Applications for Analog Circuits." Journal of Integrated Circuits and Systems 17, no. 2 (September 17, 2022): 1–7. http://dx.doi.org/10.29292/jics.v17i2.631.
Повний текст джерелаАнотація:
In this work different generations of field effect tunneling transistor (TFET) are evaluated through DC digital and analog figures of merits. For TFET devices the main digital figure of merit is the subthreshold slope (SS), while for analog application the intrinsic voltage gain (AV) is the most important one. For the early generations, that are based on silicon, the SS does not reach values smaller than 60mV/dec at room temperature, however, the AV reaches values up to 80 dB, showing to be promising for analog applications. As the TFETs were being optimized for digital applications and consequently presenting better switching performance, the intrinsic voltage gain moves in the opposite direction. This opposite trend is related to which transport mechanism is predominant for each type of device. While III-V TFETs are more dependent on Band to Band Tunneling (BTBT), silicon devices are more relying on Trap-Assisted Tunneling (TAT). While BTBT allows for faster switching, TAT is less dependent on the drain electric field, so the former favors SS while the latter favors AV. Based on the good analog behavior of silicon channel TFETs, a two-stage operational transconductance amplifier (OTA) was designed with different TFET technologies and the compared results were discussed.
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Matsuzawa, Koichi, Momo Obata, Yuu Takeuchi, Yoshiro Ohgi, Kaoru Ikegami, Takaaki Nagai, Ryuji Monden, and Akimitsu Ishihara. "(Digital Presentation) Effects of Foreign Elements Added Oxide-Based Electrocatalyst for Oxygen Reduction Reaction as Non-Precious Metel Cathodes." ECS Meeting Abstracts MA2022-01, no. 35 (July 7, 2022): 1544. http://dx.doi.org/10.1149/ma2022-01351544mtgabs.
Повний текст джерелаАнотація:
On Dec. 2020, new MIRAI of fuel cell vehicle (FCV) from Toyota started to sell in Japan. However, the price of new model is almost same as previous model. For wide commercialization of FCV, it should be required for more development. One of the barriers of innovative system for the FCV is conventional platinum-based electrocatalyst. The cost of Pt is very expensive due to its very poor resources. Moreover, the conventional Pt-based electrocatalyst cannot reach enough performance for next generation FCV that is proposed in new roadmap released from NEDO, Japan. From this point of view, the non-precious metal electrocatalyst should be required for the breakthrough against above issue. We have focused and studied group 4 and 5 metal oxide-based electrocatalyst as non-platinum catalysts for the oxygen reduction reaction (ORR) because of low-cost, abundant reserves, and high stability in acidic electrolytes [1-2]. We found that titanium oxide prepared from TiOTPyzPz supported on multi-walled carbon nanotubes had superior ORR activity [3]. On the other hand, it was published as an international patent that the addition of other elements such as Fe and Ni is affected to enhance the ORR activity of Ti oxide-based electrocatalyst [4]. In this study, we have investigated to apply for the TiOTPyzPz as a starting material with and without Fe, Ni, and Zn addition to enhance the ORR activity of Ti oxide-based electrocatalyst. 2,3-Dicyanopyrazine, urea, and Ti isopropoxide were dissolved in quinoline and refluxed to synthesize TiOTPyzPz. Iron acetate, Nickel acetate, and Zinc acetate were also added to dissolve in quinoline to obtain the Fe, Ni, and Zn-added TiOTPyzPz as a starting material. The molar ratio of Ti:Fe:Ni:Zn was set to constant. These starting materials were mixed with carbon nanotube by ball-milling to prepare the precursors. These precursors were heat-treated under low oxygen partial pressure for 3 h to obtain titanium oxide-based catalysts. The catalyst powder was dispersed into 1-propanol with Nafion solution to prepare a catalyst ink. The ink was dropped on a glassy carbon rod, and dried for an hour to use as a working electrode in electrochemical measurement. Electrochemical measurements were performed in 0.5 mol dm-3 H2SO4 at 30 oC with a conventional 3-electrode cell. A reversible hydrogen electrode (RHE) and a glassy carbon plate were used as used as a reference and counter electrode, respectively. Slow scan voltammetry (SSV) was performed at a scan rate of 5 mV s-1 from 0.2 V to 1.2 V vs. RHE under O2 and N2. The ORR current (i ORR) was determined by calculating the difference between the current under O2 and N2. Figure 1 shows the effect of Fe, Ni, and Zn addition to TiOTPyzPz as a starting material on the ORR polarization curves of the titanium oxide-based catalysts. The vertical axis is based on catalyst weight. Ti oxid-based electrocatalyst prepared from Fe, Ni, and Zn addition to TiOTPyzPz (TiOx-Fe, Ni, Zn) resulted in the increase in the onset potential for the ORR and ORR current compared to that without addition (TiOx), revealing that the addition of Fe, Ni, and Zn was found to be effective in improving the ORR activity. XRD pattern of TiOx shows several peaks identified TiO2-Rutile, TiO2-Anatanse and TiO2-Brookite while the XRD pattern of TiOx-Fe, Ni, Zn also shows several peaks identified similar to TiOx. In the case of XRD pattern of TiOx-Fe, Ni, Zn, the peak identified compounds relating to additional elements such as Fe, Ni and Zn does not detect strongly. It is suggested that the addition of Fe, Ni and Zn to TiOTPyzPz conduce to the distortion of crystal phase of TiO2 [5] and it affected to suppress the crystal growth of Ti oxide-based electrocatalyst. These facts are possibly contributed to enhance the ORR activity of TiOx-Fe, Ni, Zn compared to that of TiOx. Acknowledgement: The authors thank New Energy and Industrial Technology Development Organization (NEDO) and ENEOS Tonen General Research / Development Encouragement & Scholarship Foundation for financial support. Reference [1] A. Ishihara, Y. Ohgi, K. Matsuzawa, S. Mitsushima, and K. Ota, Electrochim. Acta, 55, 8005 (2010). [2] A. Ishihara, S. Tominaka, S. Mitsushima, H. Imai, H. Imai, O. Sugino, and K. Ota, Curr. Opin. Electrochem., 21 , 234 (2020). [3] S. Tominaka, A. Ishihara, T. Nagai, and K. Ota, ACS Omega, 2, 5209 (2017). [4] K. Takahashi, T. Imai, R. Monden, Y. Wakisaka, and S. Sato, Oxygen Reduction Catalyst, Process for Producing Same, and Polymer Electrolyte Membrane Fuel Cell, WO/2013/008501. [5] Y. Yamamoto, S. Kasamatsu, and O. Sugino, J. Phys. Chem. C, 123, 19486 (2019). Figure 1
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Vasudeva, G., and B. V. Uma. "Design and Implementation of High Speed and Low Power 12-bit SAR ADC using 22nm FinFET." WSEAS TRANSACTIONS ON SYSTEMS AND CONTROL 17 (January 3, 2022): 1–15. http://dx.doi.org/10.37394/23203.2022.17.1.
Повний текст джерелаАнотація:
Successive Approximation Register (SAR) Analog to Digital Converter (ADC) architecture comprises of sub modules such as comparator, Digital to Analog Converter and SAR logic. Each of these modules imposes challenges as the signal makes transition from analog to digital and vice-versa. Design strategies for optimum design of circuits considering 22nm FinFET technology meeting area, timing, power requirements and ADC metrics is presented in this work. Operational Transconductance Amplifier (OTA) based comparator, 12-bit two stage segmented resistive string DAC architecture and low power SAR logic is designed and integrated to form the ADC architecture with maximum sampling rate of 1 GS/s. Circuit schematic is captured in Cadence environment with optimum geometrical parameters and performance metrics of the proposed ADC is evaluated in MATLAB environment. Differential Non Linearity and Integral Non Linearity metrics for the 12-bit ADC is limited to +1.15/-1 LSB and +1.22/-0.69 LSB respectively. ENOB of 10.1663 with SNR of 62.9613 dB is achieved for the designed ADC measured for conversion of input signal of 100 MHz with 20dB noise. ADC with sampling frequency upto 1 GSps is designed in this work with low power dissipation less than 10 mW.
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Duarte, Luis, Rodolfo Gomes, Carlos Ribeiro, and Rafael F. S. Caldeirinha. "A Software-Defined Radio for Future Wireless Communication Systems at 60 GHz." Electronics 8, no. 12 (December 6, 2019): 1490. http://dx.doi.org/10.3390/electronics8121490.
Повний текст джерелаАнотація:
This paper reports on a complete end-to-end 5G mmWave testbed fully reconfigurable based on a FPGA architecture. The proposed system is composed of a baseband/low-IF processing unit, and a mmWave RF front-end at both TX/RX ends. In particular, the baseband unit design is based on a typical agile digital IF architecture, enabling on-the-fly modulations up to 256-QAM. The real-time 5G mmWave testbed, herein presented, adopts OFDM as the transmission scheme waveform, which was assessed OTA by considering the key performance indicators, namely EVM and BER. A detailed overview of system architecture is addressed together with the hardware considerations taken into account for the mmWave testbed development. Following this, it is demonstrated that the proposed testbed enables real-time multi-stream transmissions of UHD video content captured by nine individual cameras, which is in fact one of the killing applications for 5G.
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Matsuzawa, Koichi, Atsushi Nozaka, and Akimitsu Ishihara. "(Digital Presentation) Mo Added Zr Oxide-Based Thin Film for Oxygen Evolution Catalyst in Alkaline Solution." ECS Meeting Abstracts MA2022-01, no. 34 (July 7, 2022): 1347. http://dx.doi.org/10.1149/ma2022-01341347mtgabs.
Повний текст джерелаАнотація:
On Oct. 4, 2021, Hydrogen energy ministerial meeting (H2 EM 2021) was held by the ministry of economy, trade and industry (METI) of Japanese government as online special event with cabinet members and officials from 29 countries, regions, and organizations. In the meeting, “Global Hydrogen Review 2021” and was released to propose the policy toward hydrogen-based society. In the open session, the water electrolysis was one of the main session, and participants shared their commitment to improve the performance of water electrolysis units and optimize the relevant systems with a view toward reducing the costs of “Green Hydrogen”, and exchanged views on topics including the future prospects for the “Green Hydrogen” market [1]. Here, “Green Hydrogen” is the hydrogen which is produced by the electricity from renewable energies introducing in our previous study [2]. Alkaline water electrolysis (AWE) has already commercialized all over the world and recently applied its system for the Power-to-Gas (PtG) in Europe and Japan such as Fukushima hydrogen energy research field (FH2R). In the FH2R, one of the largest module of AWE has operated from 2020. However, we found that the degradation of Ni anode occurs operating by variable renewable energy (VNE) from our previous report [3]. From this point of view, the alternative anode with high durability against VNE should be required for green hydrogen production. We focused on zirconium oxide-based electrocatalyst (ZrOx) and have studied its catalytic activity for oxygen evolution reaction (OER) [4]. In this study, we have investigated the activity and durability of ZrOx with and without Mo addition for the OER in alkaline solution. Zr compound films were formed on Ti rods as a base material, using the R.F. magnetron sputtering. Gas atmosphere in the chamber was a mixture of Ar and O2 gas. After polishing and washing, the Ti rods were heated at 300 oC for Zr oxide-based film without any addition (ZrOx), and 350 oC for Zr oxide-based film with Mn addition (Mn-ZrOx). Sputtering power and sputtering time were fixed at 150 W and 20 min, respectively. All electrochemical measurements were carried out using a three-electrode cell at 30 oC in 7 M KOH. A reversible hydrogen electrode (RHE) and a carbon plate were used as a reference and a counter electrode, respectively. ZrOx or Mo-ZrOx was used as working electrode. In order to evaluate the catalytic activity for the OER, slow scan voltammetry (SSV) was performed under N2 atmosphere. Current density (i geo) was based on the geometric surface area of the working electrode. The resistance of the film (R film) and charge transfer (R ct) was evaluated by AC impedance spectroscopic measurements in the frequency range from 105 to 10−1 Hz. Figure 1 shows polarization curves of ZrOx and Mo-ZrOx. The i geo for the OER on Mo-ZrOx has obviously larger than that of ZrOx. According to the cyclic voltammograms (CV) of both sample, the electric double layer (C dl) of Mo-ZrOx from CV was larger than that of ZrOx. This trend was similar to the result reported in previous study [5], and it is suggested that the C dl becomes larger by the effect of Mo addition. From the results of electrochemical impedance spectroscopy (EIS), both ZrOx and Mo-ZrOx are n-type semiconductor. Moreover, the slope of Mott-Schottky plot on Mo-ZrOx was more gentle than that on ZrOx and it is suggested that the electric conductivity of Mo-ZrOx was larger than that of ZrOx. Thus, the reason why the i geo for the OER on Mo-ZrOx has larger than that of ZrOx is that both improvement of the increase of C dl and the electric conductivity of sample. Acknowledgement: This work is partially supported by Iketani Science and Technology Foundation. Reference [1] https://www.meti.go.jp/english/press/2021/1008_001.html [2] K. Ota, A. Ishihara, K. Matsuzawa, and S. Mitsushima, Electrochemistry, 78, 970 (2010). [3] H. Ichikawa, K. Matsuzawa, Y. Kohno, I. Nagashima, Y. Sunada, Y. Nishiki, A. Manabe, and S. Mitsushima, ECS Trans., 58(33), 9 (2014). [4] K. Matsuzawa, A. Ishihara, A. Ohshi, S. Mitsushima, and K. Ota, Mater. Sci. Eng. B, 267, 115112 (2020). [5] Y. Takasu, T. Ohnuma, W. Sugimoto, and Y. Murakami, Electrochemistry, 67, 1187 (1999). Figure 1
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Lodro, Mir, Chris Smart, Gabriele Gradoni, Ana Vukovic, Dave Thomas, and Steve Greedy. "Near-field BER and EVM Measurement at 5.8 GHz in Mode-stirred Metal Enclosure." Applied Computational Electromagnetics Society 35, no. 9 (November 4, 2020): 1080–88. http://dx.doi.org/10.47037/2020.aces.j.350915.
Повний текст джерелаАнотація:
This work presents over-the-air (OTA) performance, near-field bit-error-ratio (BER), and error vector magnitude (EVM) measurement using software-defined radio (SDR) in the mode-stirred metal enclosure at 5.8 GHz. The metal enclosure is stirred at 5.8 GHz using metallic paddle rotating with uniform speed. Paddle rotation creates a uniform electromagnetic field in the metal enclosure. The electromagnetic field environment in the metal enclosure can be controlled by loading the cavity with absorbing material. Field absorption can be different depending on the amount of absorbing material and location of the absorbers in the metal enclosure. It is shown that signal attenuation increases as we increase the number of absorbers. BER and EVM are measured in this environment and the performance of SDR based digital receiver is analyzed in this environment at RF frequency of 5.8 GHz.
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Ren, Xiaojiao, Ming Zhang, Nicolas Llaser та Yiqi Zhuang. "On-Chip Measurement of Quality Factor Implemented in 0.35μm CMOS". Journal of Circuits, Systems and Computers 25, № 08 (17 травня 2016): 1650087. http://dx.doi.org/10.1142/s0218126616500870.
Повний текст джерелаАнотація:
Based on time-domain quality factor (Q-factor) measurement principle, we have proposed an architecture which has the potential to be integrated on-chip. Thanks to the proposed original reconfigurable structure, the main measurement error from the offset of the operational transconductance amplifier (OTA) used can be cancelled automatically during the measurement operation, leading to a high accuracy Q-factor measurement. The digital control circuit plays an important role in the automatic passage between the two configurations designed, i.e., peak detector and comparator. The main advantages of the proposed time-domain Q-factor measurement lay on the possibility of being integrated next to the Micro Electro Mechanical System (MEMS) resonator to be measured, the miniaturization of the whole measuring system as well as the enhancement of the measurement performance, and to guide the design of such architecture, a theoretical analysis linking the required accuracy and the given Q-factor to the circuit parameters have been given in this paper. The proposed circuit is designed and simulated in a 0.35[Formula: see text][Formula: see text]m Complementary Metal Oxide Semiconductors (CMOS) technology. The post-layout simulation results show that the operating frequency can reach up to 200[Formula: see text]kHz with an accuracy of 0.4%.
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Ngo, Thi Khue Thu, Phuong Thao Nguyen, Thang Le Dinh, and Nguyen Anh Khoa Dam. "The Implementation of Integrated Multichannel Services in the Hospitality Sector in Vietnam." ITM Web of Conferences 51 (2023): 05003. http://dx.doi.org/10.1051/itmconf/20235105003.
Повний текст джерелаАнотація:
The research streams on multichannel integration (MCI) in the hospitality sector recently caught the attention of academics and practitioners. However, knowledge and understanding of integrated multichannel services are still unfamiliar to enterprises, especially small and medium-sized enterprises (SMEs) and enterprises in developing countries like Vietnam. Since this topic is limitedly exploited in the hospitality industry, the paper explores the opportunities and challenges for implementing integrated multichannel services in the hospitality sector in Vietnam based on the service science perspective. In the context of emerging digital technology and changing consumer behaviour today, an exploratory study on integrated multichannel services of hotels was conducted on eight hotel managers, eight online travel agencies (OTA), and sixteen domestic tourists. The results show the variety of channels of hotels can reach customers thanks to integrated multichannel services. However, the current situation of channel integration (between the direct and the indirect channel of the hotel through online travel intermediaries) is currently inconsistent. For this reason, challenges related to integrated services, promotion and price, and information access in the channel integration of the selected hotels have been explored. Since then, several solutions are suggested to accelerate MCI in the hospitality sector to stimulate demand for domestic tourism.
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Al-Ali, Abdulrahman Khalaf, Muhammad Taher Abuelma'atti, and Rizwan Ali Tiwana. "Programmable OTA-Based Multifunction Active Filter." Active and Passive Electronic Components 17, no. 1 (1994): 21–27. http://dx.doi.org/10.1155/1994/10413.
Повний текст джерелаАнотація:
A fully programmable multifunction filter is presented. The filter uses four operational transconductance amplifiers and two capacitors. Analog switches are used to control the filter transfer function through a microcontroller. The user is provided control over the cutoff (or centre) frequency of the filter by controlling the auxiliary bias currents of the operational transconductance amplifiers via digital-to-analog converters. The circuit can simultaneously provide three programmable transfer functions in a single structure and can realize all the standard second-order filters. The circuit is attractive for VLSI implementation.
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Varnavas, Kosta. "Advanced Wireless Sensor Nodes - MSFC." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2017, DPC (January 1, 2017): 1–19. http://dx.doi.org/10.4071/2017dpc-ta3_presentation4.
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IMAPS Device Packaging Conference 2017 Engineered Micro Systems & Devices Track Advanced Wireless Sensor Nodes - MSFC Abstract Kosta Varnavas NASA / Marshall Space Flight Center NASA field center Marshall Space Flight Center (Huntsville, AL), has invested in advanced wireless sensor technology development. Developments for a wireless microcontroller back-end were primarily focused on the commercial Synapse Wireless family of devices. These devices have many useful features for NASA applications, good characteristics and the ability to be programmed Over-The-Air (OTA). The effort has focused on two widely used sensor types, mechanical strain gauges and thermal sensors. Mechanical strain gauges are used extensively in NASA structural testing and even on vehicle instrumentation systems. Additionally, thermal monitoring with many types of sensors is extensively used. These thermal sensors include thermocouples of all types, resistive temperature devices (RTDs), diodes and other thermal sensor types. The wireless thermal board will accommodate all of these types of sensor inputs to an analog front end. The analog front end on each of the sensors interfaces to the Synapse wireless microcontroller, based on the Atmel Atmega128 device. Once the analog sensor output data is digitized by the onboard analog to digital converter (A/D), the data is available for analysis, computation or transmission. Various hardware features allow custom embedded software to manage battery power to enhance battery life. This technology development fits nicely into using numerous additional sensor front ends, including some of the low-cost printed circuit board capacitive moisture content sensors currently being developed at Auburn University.
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Rerkratn, Apinai, Jakkapun Tongcharoen, Wandee Petchmaneelumka, and Vanchai Riewruja. "Linear-Range Extension for Linear Variable Differential Transformer Using Hyperbolic Sine Function." Sensors 22, no. 10 (May 12, 2022): 3674. http://dx.doi.org/10.3390/s22103674.
Повний текст джерелаАнотація:
In this paper, a circuit technique to extend the measuring range of a linear variable differential transformer (LVDT) is proposed. The transfer characteristic of the LVDT contains the odd function form of the cubic polynomial. Therefore, the measuring range of a commercial LVDT is linear in a narrow range compared to its physical dimensions. The wide measuring range of the LVDT requires a large structure of the LVDT, which increases the scale and the cost of the measurement system. The measuring range of the LVDT can be linearly extended to the maximum of the stroke range using the proposed technique. The realization of the proposed technique is based on the use of the hyperbolic sine (sinh) function of the electronic circuit building block, named the class AB bipolar amplifier. The class AB bipolar amplifier can be obtained by the current feedback operational amplifier (CFOA). The circuit of the proposed technique requires two CFOAs and an operational transconductance amplifier (OTA) as the active devices and all devices used in the proposed technique to synthesize the sinh function are commercially available. The proposed technique exhibits an ability to compensate for the nonlinear characteristic of the LVDT without digital components. The proposed technique is attractive in terms of its simple circuit configuration, small size, and low cost. The linear range extension of the LVDT used in this paper is significantly increased with a maximum error of about 18.3 μm of 6.2 mm at the full stroke range or the full-scale percentage error of about 0.295%. The results indicate that the proposed technique provides excellent performance to extend the measuring range of the LVDT without modifying the LVDT structure.
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Matsuzawa, Koichi, Yuma Kohara, Soma Hirayama, Satoshi Yamada, and Akimitsu Ishihara. "(Digital Presentation) Oxygen Evolution Reaction on Non-Precious Metal Oxide-Based Electrocatalysts With and Without Low Potential Scan in Acidic Solution." ECS Meeting Abstracts MA2022-02, no. 44 (October 9, 2022): 1690. http://dx.doi.org/10.1149/ma2022-02441690mtgabs.
Повний текст джерелаАнотація:
Hydrogen energy ministerial meeting (H2 EM 2021) was held on Oct. 4, 2021 by the ministry of economy, trade and industry (METI) of Japanese government as online special event with cabinet members and officials from 29 countries, regions, and organizations. In the industrial session, 4 sessions were held, and the water electrolysis was one of the themes of industrial session. Panelists from several countries introduced state-of-art technologies of water electrolyzer [1]. In our previous study, the hydrogen producing from renewable energies is called as “Green Hydrogen” [2]. Proton exchange membrane water electrolysis (PEMWE) has partly commercialized and recently applied its system for the Power-to-Gas (PtG). However, conventional anode is precious metal oxide such as IrO2 and the cost of raw material is expensive. From this point of view, the non-precious metal oxide anode should be required for green hydrogen production. We focused on tantalum and molybdenum oxide-based electrocatalyst (TaOx and MoOx) and have studied its catalytic activity for oxygen evolution reaction (OER) [3]. Moreover, TaOx with Mn addition showed much higher the OER activity than TaOx [4]. In this study, we have applied for MoOx with Mn addition for investigating the catalytic activity for the OER in acidic solution. Ti rod was used as substarate. MoOx was prepared by RF magnetron sputtering method. In the case of fabrication for Mn-MoOx, Mo metal piece for 40% surface area was set on the Mn disc as additional material. Each partial pressure of Ar and O2 gas was adjusted to 0.15 Pa in fabrication of Mn-MoOx. The substrate heating temperature was constant at 673 K during sputtering. We used conventional three electrode cell with each sample as working electrode while the reversible hydrogen electrode (RHE) and carbon plate were used as reference and counter electrode to demonstrate the electrochemical measurement in 1 M H2SO4 solution with saturated nitrogen atmosphere at 303 K. Several samples were demonstrated pretreatment from 0.05 to 1.2 V vs. RHE before the measurement of OER. The slow scan voltammetry was performed from 1.2 to 2.0 V to evaluate the OER activity. We also carried out electrochemical impedance spectroscopy (EIS) to obtain resistance components and semiconducting properties. In addition, samples before and after electrochemical measurement were analyzed by SEM-EDX and XPS. Figure 1 shows the Tafel plots of OER on Mo oxide-based electrocatalysts with and without Mn addition. The current density was based on geometric surface area. In the case of sample performing pretreatment, the Mn-MoOx with pretreatment (Mn-MoOx(Pre)) has obviously higher OER current than MoOx with pretreatment (MoOx(Pre)). Moreover, Mn-MoOx has higher OER current than Mn-MoOx(Pre), and the Tafel slope of OER on Mn-TaOx was 79 mV dec-1 the while the that on the Mn-MoOx(Pre) was 147 mV dec-1. From the results of EIS, the charge transfer resistance of Mn-MoOx was much smaller than that of Mn-MoOx(Pre) while the film resistance of was similar to that of Mn-MoOx(Pre). The results from SEM-EDX revealed that Mn amount in Mn-MoOx after the electrochemical measurement was constant compared to that before electrochemical measurement while Mn amount in Mn-MoOx(Pre) after electrochemical measurement was decreased compared to that before electrochemical measurement. From results from XPS analysis, Mn ratio in the Mn-MoOx after electrochemical measurement was constant compared to that before electrochemical measurement while Mn amount in Mn-MoOx(Pre) after electrochemical measurement was decreased compared to that before electrochemical measurement. Therefore, Mn species still remained on both surface and bulk in the case of Mn-MoOx while it was decreased in the case of Mn-MoOx(Pre). In Fig. 1, The peak over 1.5 V was detected from Tafel plots of both Mn-MoOx and Mn-MoOx(Pre). This peak corresponded to redox peak of Mn(III)/Mn(IV) [5], and it implied that Mn species affected on the OER activity. However, the electric charge of Mn(III)/Mn(IV) of Mn-MoOx was smaller than that of Mn-MnOx(Pre), and it is suggested that not only Mn oxide but also other species such as Mn-Mo compound oxide reacts as an active site of OER on Mn-MoOx. Acknowledgement: This work is partially supported by the Suzuki Foundation. Reference https://www.meti.go.jp/english/press/2021/1008_001.html Ota, A. Ishihara, K. Matsuzawa, and S. Mitsushima, Electrochemistry, 78, 970 (2010). Matsuzawa, S. Hirayama, K. Sumi, A. Ishihara, Abst. PRiME2020, I01F-2492, Online (2020). Matsuzawa, S. Hirayama, Y. Kohara, and A. Ishihara, ECS Trans, 104(8), 431 (2021). M. Morita, C. Iwakura, and H. Tamura, Electrochim. Acta, 24, 357 (1979). Figure 1
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Hwang, Chyi, Fang-Pi Chang, and Jyh-Haur Hwang. "Digital redesign of analog controllers based on minimizing integral of squared errors." Optimal Control Applications and Methods 24, no. 1 (January 2003): 1–22. http://dx.doi.org/10.1002/oca.716.
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Bonitz, L., A. Pugachev, M. Arnold, U. Janoske, S. Hassfeld, D. Abel, A. Bicsak, and C. Mueller. "“Digital Twin” based approach to patient specific diagnosis and therapy of OSA." Sleep Medicine 64 (December 2019): S45. http://dx.doi.org/10.1016/j.sleep.2019.11.124.
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Monaldi, A. C., G. G. Romero, A. V. Blanc, and C. M. Cabrera. "An automatic wrapped phase gradient-based method for spherical aberration correction in Digital Holographic Microscopy." Optica Pura y Aplicada 51, no. 3 (October 5, 2018): 1–8. http://dx.doi.org/10.7149/opa.51.3.49032.
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Jellen, E. N., R. L. Phillips, and H. W. Rines. "C-banded karyotypes and polymorphisms in hexaploid oat accessions (Avena spp.) using Wright's stain." Genome 36, no. 6 (December 1, 1993): 1129–37. http://dx.doi.org/10.1139/g93-151.
Повний текст джерелаАнотація:
A chromosome C-banding protocol using Wright's stain was employed to compare chromosomes in cultivars and wild accessions of several hexaploid oat taxa (Avena spp.). This technique permits the identification of each of the 21 somatic hexaploid oat chromosomes. Digital images of C-banded cells were captured on computer and used to construct karyotypes of several oat accessions. Polymorphisms for C-bands among oat cultivars and wild accessions are described. These banding polymorphisms can be used to trace introgression of chromosomes from wild sources and to provide physical markers on the genetic map for oat. Although C-banding permits the identification of likely C-genome chromosomes based on comparisons with C-banding patterns in diploid and tetraploid Avena species, the A and D genomes cannot be readily differentiated based on their banding patterns.Key words: Avena, C-banding, oat, image analysis.
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Huang, C. M., J. S. H. Tsai, R. S. Provence, and L. S. Shieh. "The observer-based linear quadratic sub-optimal digital tracker for analog systems with input and state delays." Optimal Control Applications and Methods 24, no. 4 (2003): 197–236. http://dx.doi.org/10.1002/oca.731.
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Li, Hao, Cheng Yang, and Jia Yin Tian. "OMA DRM-Based Key Management Protocol for IPTV." Applied Mechanics and Materials 733 (February 2015): 815–20. http://dx.doi.org/10.4028/www.scientific.net/amm.733.815.
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Nowadays, with the development of hardware platform, digital content can be presented in more varieties of forms. The authorized users not only watch the authorized TV programs, but also are willing to do it via mobile phones and I-pad. Although the contemporary OMA DRM system provides an approach named domains to adapt multi-screens and services about the authorization of offline digital content, standard PKI procedures used to authenticate the DRM Agent, with the calculation and power consumption relatively larger, are not beneficial for the mobile terminal. Meanwhile, as the public key distribution is complex and the authorization is difficult, it is also not helpful for applied environment of multi-screens. Based on the authentication of hardware devices, the uniqueness of hardware ID also cannot meet the actual demand of multi-screen user. In this paper, we will propose a new protocol of key distribution based on OMA DRM. The protocol meets the requirements of low power consumption and multiple-screen, while providing the feasible security.
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Fernandez, J. "Design and implementation of a colorimetric system for clinical analysis based in a digital camera and diffused lightning." Optica Pura y Aplicada 45, no. 3 (September 2012): 315–21. http://dx.doi.org/10.7149/opa.45.3.315.
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Eichhorn, S. Holger, Simon Rondeau-Gagné, Elmahdy Abdulhamied, and M. Nazir Tahir. "(Digital Presentation) Photopolymerization of Tetraazaporphyrin Based Surfactants and Mesogens." ECS Meeting Abstracts MA2022-01, no. 14 (July 7, 2022): 943. http://dx.doi.org/10.1149/ma2022-0114943mtgabs.
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Intermolecular interactions between tetraazaporphyrin (TAP) macrocycles are less dominated by π-π stacking interactions than interactions between their larger phthalocyanine derivatives. Consequently, the self-organization and -assembly of TAPs is more widely altered by changes to the type of complexed metal ion and substitution pattern. Presented here are different molecular designs for mesomorphic and amphiphilic TAPs that could be cross-linked by “click” chemistry and by the photo and thermal polymerization of diacetylene groups. All compounds were studied by polarized optical microscopy, thermal analysis, and X-ray diffraction to probe their (meso)phase structures and transitions and by the Langmuir-Blodget method to quantify their interfacial properties. Potential applications for these compounds include their use as active materials in sensors, functional coatings for metal oxide nanoparticles, and building blocks for dye nanoparticles. Topochemical Polymerization of a Nematic Tetraazaporphyrin Derivative to Generate Soluble Polydiacetylene Nanowires. M. Nazir Tahir, et al., 2019, Langmuir, 35(47) 15158−15167. Self-organization of Porphyrins and Phthalocyanines in two and three dimensions by S. Holger Eichhorn and Elmahdy Abdulhamied, in “Handbook of Porphyrin Science: Towards Tuned Properties of Porphyrinoids”, Vol. 42, Karl M. Kadish, Kevin M. Smith, Roger Guilard, Eds., World Scientific, Singapore, 2016, 173-232. Cross-linking of discotic tetraazaporphyrin dyes in 2 and 3 dimensions by “click” chemistry. Himadri Kayal, et al., 2013, J. Mater. Chem. C, 1(42), 7064-7072. Face- and edge-on orientations of octa-acid and -alcohol substituted tetraazaporphyrins in langmuir and Langmuir-Blodgett monolayers. M. M. Ahmida, et al., 2013, Soft Matter 9 (3), 811-9.
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Stoeklen, Phillip, Justin J. Sullivan, M. Justin Miller, Meridith Drzakowski, and Sasha King. "eStout: a digital learning environment program case study." On the Horizon 25, no. 4 (September 11, 2017): 242–49. http://dx.doi.org/10.1108/oth-02-2017-0005.
Повний текст джерелаАнотація:
Purpose This paper aims to discuss the evolution of a digital learning environment in higher education as a result of ongoing data collection and evaluation. Design/methodology/approach The manuscript is based on a digital learning environment intervention at the University of Wisconsin-Stout and is informed by evaluation data collected from student and faculty surveys annually between 2002 and 2016. Survey themes changed annually based on student/faculty concerns and interests, and program management used this feedback to make modifications to program scope and offerings. Findings The digital learning environment at the University of Wisconsin-Stout has been effective in providing faculty and students with the tools they need to be successful. This success is largely due to the ongoing commitment to data collection and evaluation at the University of Wisconsin-Stout and has ensured that the digital learning environment stays modern and adaptive. Originality/value This manuscript is the culmination of 15 years of ongoing evaluation practice and thus provides valuable best practices and lessons learned for educators/educational institutions hoping to improve or create their own digital learning environment.
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Komarizadehasl, Seyedmilad, Pierre Huguenet, Fidel Lozano, Jose Antonio Lozano-Galant, and Jose Turmo. "Operational and Analytical Modal Analysis of a Bridge Using Low-Cost Wireless Arduino-Based Accelerometers." Sensors 22, no. 24 (December 14, 2022): 9808. http://dx.doi.org/10.3390/s22249808.
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Arduino-based accelerometers are receiving wide attention from researchers to make long-term Structural Health Monitoring (SHM) feasible for structures with a low SHM budget. The current low-cost solutions found in the literature share some of the following drawbacks: (1) high noise density, (2) lack of wireless synchronization, (3) lack of automatic data acquisition and data management, and (4) lack of dedicated field tests aiming to compare mode shapes from Operational Modal Analysis (OMA) with those of a digital model. To solve these problems, a recently built short-span footbridge in Barcelona is instrumented using four Low-cost Adaptable Reliable Accelerometers (LARA). In this study, the automatization of the data acquisition and management of these low-cost solutions is studied for the first time in the literature. In addition, a digital model of the bridge under study is generated in SAP2000 using the available drawings and reported characteristics of its materials. The OMA of the bridge is calculated using Frequency Domain Decomposition (FDD) and Covariance Stochastic Subspace Identification (SSI-cov) methods. Using the Modal Assurance Criterion (MAC), the mode shapes of OMA are compared with those of the digital model. Finally, the acquired eigenfrequencies of the bridge obtained with a high-precision commercial sensor (HI-INC) showed a good agreement with those obtained with LARA.
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Rizal, Achmad, Sugondo Hadiyoso, Hilman Fauzi, and Rahmat Widadi. "Obstructive Sleep Apnea Detection based on ECG Signal using Statistical Features of Wavelet Subband." International journal of electrical and computer engineering systems 13, no. 10 (December 21, 2022): 877–84. http://dx.doi.org/10.32985/ijeces.13.10.13.
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One of the respiratory disorders is obstructive sleep apnea (OSA). OSA occurs when a person sleeps. OSA causes breathing to stop momentarily due to obstruction in the airways. In this condition, people with OSA will be deprived of oxygen, sleep awake and short of breath. Diagnosis of OSA by a doctor can be done by confirming the patient's complaints during sleep, sleep patterns, and other symptoms that point to OSA. Another way of diagnosing OSA is a polysomnography (PSG) examination in the laboratory to analyze apnea and hypopnea. However, this examination tends to be high cost and time consuming. An alternative diagnostic tool is an electrocardiogram (ECG) examination referring to changes in the mechanism of ECG-derived respiration (EDR). So digital ECG signal analysis is a potential tool for OSA detection. Therefore, in this study, it is proposed to classify OSA based on ECG signals using wavelets and statistical parameters. Statistical parameters include mean, variance, skewness kurtosis entropy calculated on the signal decomposition results. The validation performance of the proposed method is carried out using a support vector machine, k-nearest neighbor (k-NN), and ensemble classifier. The proposed method produces the highest accuracy of 89.2% using a bagged tree where all features are used as predictors. From this study, it is hoped that ECG signal analysis can be used to complete clinical diagnosis in detecting OSA.
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Yoshimura, Takeshi. "(Invited, Digital Presentation) Investigation of Polarization Behavior of HfO2 Thin Films Via Piezoelectric Characterization." ECS Meeting Abstracts MA2022-02, no. 15 (October 9, 2022): 807. http://dx.doi.org/10.1149/ma2022-0215807mtgabs.
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Nonvolatile memory based on field-effect transistors with ferroelectric gate dielectrics (FeFET) was first proposed in the 1960s[1]. Later, in the 1990s, FeFETs were proposed to operate as neuromorphic devices and were actively studied[2]. However, it has not been realized due to the difficulty of forming ferroelectric thin films on Si and obtaining a good Si/ferroelectric interface. This situation was greatly changed by the discovery of ferroelectricity in hafnium oxides [3]. Now, FeFETs have attracted attention again due to the high CMOS process compatibility of hafnium oxides as well as their good ferroelectricity even in ultra-thin films. FeFETs have many potential applications, including steep switching transistors and reservoir computing as well as nonvolatile memory. In addition, the understanding of the ferroelectric properties of HfO2-based thin films has been deepened. On the other hand, reliability issues such as robustness, switching endurance, fatigue characteristics, wake-up effects, and imprinting still remain to be addressed for practical applications. These are problems common to ferroelectric thin films, but because HfO2 is an ultra-thin film, they are not easy to analyze. Therefore, in this study, we focused on the evaluation of ferroelectricity by the direct piezoelectric effect. In contrast to the inverse piezoelectric response, the direct piezoelectric response is, in principle, independent of the film thickness, so we expect that the direct piezoelectric response could be analyzed even for HfO2-based thin films. TaN/Hf0.5Zr0.5O2 (HZO)/TaN capacitor was prepared on a Si wafer. TaN electrodes were deposited by DC sputtering method. The thickness of the TaN films was 10 nm. The HZO film was then deposited by the RF magnetron sputtering method using HfO2 and ZrO2 targets. The fabricated capacitor was annealed in a rapid thermal annealing system at 700 °C. The details of the deposition are described in Ref. 4. The direct piezoelectric response of the HZO film was measured using the wafer flexure technique [5]. The strain was applied periodically to the sample, and the charge induced via the direct piezoelectric response was measured using a lock-in amplifier. While the conventional ferroelectric characterization, including the P-E measurement, might be influenced by the space charge, leakage current so on, the direct piezoelectric response only depends on the remaanenrt polarization because there are no other physical phenomena similar to the direct piezoelectric response. We investigated the state of polarization during the retention and wake-up process. The film showed a time-dependent imprint at room temperature during polarization retention. The internal electric field that generated the imprint gradually increased from 0.05 to 0.6 MV/cm. In contrast, the magnitude of the direct piezoelectric response did not change during the polarization retention. Similar analyses were also carried out for the wake-up process. Based on the obtained results, we concluded that the non-ferroelectric layer exists at the interface between the HZO film and TaN electrode and gradually transitions to ferroelectric phases through the electric field cycle[6]. The presentation will also cover the domain observation of HZO films by the direct piezoeelectric response. [1] J. L. Moll and Y. tarui, IEEE trans. Elect. Dev., ED-10, 338 (1963) [2] H. Ishiwara, Jpn. J. Appl. Phys., 32, 442 (1993) [3] T. S. Boscke, J. Muller, D. Brauhaus, U. Schroder, and U. Bottger, Appl. Phys. Lett. 99, 102903 (2011). [4] S. Migita, H. Ota, H. Yamada, K. Shibuya, A. Sawa, and A. Toriumi, Jpn. J. Appl. Phys., Part 1 57, 04FB01 (2018). [5] J. F. Shepard, P. J. Moses, and S. Trolier-McKinstry, Sens. Actuators, A 71, 133 (1998). [6] K. Takada, M. Murase, S. Migita, Y. Morita, H. Ota, N. Fujimura, and T. Yoshimura, Appl. Phys. Lett. 119, 032902 (2021)
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Muralidhar, Srihari Hulikal. "Making Digital Money “Work” for Low-Income Users." International Journal of Mobile Human Computer Interaction 11, no. 4 (October 2019): 49–65. http://dx.doi.org/10.4018/ijmhci.2019100105.
Повний текст джерелаАнотація:
This paper adds to the research on digitization and money in HCI. By presenting a case of rickshaw drivers in India and their use of Ola, an app-based taxi service like Uber, and Ola Money, an embedded m-wallet, this paper makes a threefold contribution. First, it shows how cash and digital money are not simply different manifestations of the ‘same' money for users. They provide distinct affordances and have different meanings and values, yielding rich insights for design. Second, it seeks to highlight the hidden work done by users around making digital money ‘work' for them. In doing so, it calls for a broader understanding of ‘moneywork' that goes beyond a temporal analysis, through the concept of ‘mobility work'. Finally, it highlights the role of ‘friction' in design. Friction is crucial to users' negotiation of the trade-off between consumption and saving, and can be leveraged to provoke reflection and user-awareness.
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Ozkececi, Gulay, Sevinc Sarinc Ulasli, Onder Akci, Alaettin Avsar, Mehmet Unlu, and Ersel Onrat. "The effect of sleep apnea severity on cardiac autonomic activity during night time in obstructive sleep apnea patients." Sao Paulo Medical Journal 134, no. 5 (June 27, 2016): 430–36. http://dx.doi.org/10.1590/1516-3180.2015.0189070116.
Повний текст джерелаАнотація:
ABSTRACT CONTEXT AND OBJECTIVE: Impaired autonomic cardiac function is an important consequence of obstructive sleep apnea (OSA). This impairment is mainly due to intermittent hypoxia episodes following apneas. However, the impact of apnea severity on autonomic cardiac function remains unclear. The aim of this study was to evaluate the relationship between the severity of sleep apnea and heart rate turbulence (HRT) and heart rate variability (HRV) in OSA. DESIGN AND SETTING: Observational cross-sectional study conducted in the Departments of Cardiology and Pulmonary Diseases, Afyon Kocatepe University, Turkey. METHODS: 106 patients with OSA and 27 healthy volunteers were enrolled. Based on apnea hypopnea index (AHI) values, obstructive sleep apnea severity was classified as follows: mild OSA (AHI ≥ 5 and < 15), moderate OSA (AHI ≥ 15 and ≤ 30) and severe OSA (AHI > 30). HRV and HRT parameters were assessed via 24-hour digital Holter electrocardiogram recordings for all subjects. RESULTS: HRV and HRT results were significantly lower among OSA patients than among control subjects (P < 0.05). However, there were no significant differences in HRT and HRV between the three patient subgroups. Correlations did emerge between AHI and the NN-interval parameter RMSSD and between oxygen desaturation and turbulence slope (respectively: r = -0.22, P = 0.037; and r = -0.28, P = 0.025). CONCLUSION: HRT and HRV results deteriorate in OSA. Correlations between apnea severity and these parameters seem to be present.
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Grishina, Elena N., Elena A. Lysova, Irina P. Lapteva, and Eleonora V. Nagovitsyna. "Educational platform of region’s digital modernization in Industry 4.0." On the Horizon 27, no. 3/4 (October 11, 2019): 180–86. http://dx.doi.org/10.1108/oth-07-2019-0040.
Повний текст джерелаАнотація:
Purpose The purpose of this paper is to substantiate the importance of an educational platform for digital modernization of modern Russia’s regions in Industry 4.0 and to determine the functions and conceptual foundations of organization of regional market of educational services for execution of functions for stimulation of digital modernization of Russia’s regional economy. Design/methodology/approach The authors use the method of regression analysis for studying the influence of the indicators of adaptation of the market of educational services to the conditions of Industry 4.0 on efficiency of digital modernization of economy of the regions of the Volga Federal District of the Russian Federation as of late 2018-early 2019. The information and empirical basis of the paper is materials of the index “Digital Russia” of the Moscow School of Management “Skolkovo.” Findings It is determined that the market of educational services plays an important role in the process of transition of regions of modern Russia to Industry 4.0, performing two functions: training of personnel who are capable of working with digital technologies and training of personnel who are capable of creating new digital technologies at a region’s companies. As a result, the educational platform of digital modernization of the regional economy is formed. The developed conceptual foundations of an organization of the regional market of educational services for execution of its functions on stimulating the digital modernization of Russia’s regional economy allow for three variants of the process of training of personnel: within execution of the order of partner companies in a regional technological park, within participation of the region’s companies in a tender for training of personnel and within an independent initiation of the process of training of personnel by universities based on the results of digital marketing. Originality/value The offered authors’ recommendations ensure the following advantages during the creation and development of the educational platform of a region’s digital modernization in Industry 4.0: high marketing activity of universities, direct sequence of training of personnel and improved treatment of the effectiveness of regional universities as the ratio of efficiency in personnel training to expenditures, which stimulates competition between universities and maximization of effectiveness of educational platform of a region’s digital modernization in Industry 4.0.
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Grabar, Anna A., Tatiana L. Koykova, Lyudmila K. Prokopenko, and Raisa A. Shchinova. "The innovative mechanism of government support for the investment activities of digital universities for provision of region’s investment attractiveness in the conditions of Industry 4.0." On the Horizon 27, no. 3/4 (October 11, 2019): 159–65. http://dx.doi.org/10.1108/oth-07-2019-0041.
Повний текст джерелаАнотація:
Purpose The purpose of this study is to substantiate the necessity and to develop the innovative mechanism of government support for the investment activities of digital universities for provision of region’s investment attractiveness in the conditions of Industry 4.0. Design/methodology/approach The authors use the method of regression analysis for determining the dependence of the aggregate volume of investments (internal and external), which are attracted into the regional economy, on the volume of investments into fixed capital in the sphere of education (as the indicator of investment activities in the sphere of digital education) by the example of the regions of the Volga Federal District of the Russian Federation in 2018. Findings It is substantiated that the modern Russian mechanism of government support for investment activities of universities (including digital), which is based on such tools as norming and standardization, tax preferences and co-financing, does not allow for full implementation of the existing potential of digital universities in increasing region’s investment attractiveness in the conditions of Industry 4.0, which reduces the investment rating and volume of attracted investment resources in the regional economy – as is shown by the example of the regions of the Volga Federal District of the Russian Federation. Originality/value The determined problem could be solved by the presented innovative mechanism of government support for the investment activities of digital universities for provision of region’s investment attractiveness in the conditions of Industry 4.0. It is implemented on the basis of new – for modern Russia – tools: information and consultation support for investment activities and institutional support for integrating digital universities for joint realization of the investment projects in a region. The advantage of the developed mechanism is transfer of the financial load and responsibility for the investment activities from the state to digital universities because of the creation of market stimuli for conducting these activities.
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Afrilia, Ascharisa Mettasatya. "DIGITAL MARKETING SEBAGAI STRATEGI KOMUNIKASI PEMASARAN “WAROENK ORA UMUM” DALAM MENINGKATKAN JUMLAH KONSUMEN." Jurnal Riset Komunikasi 1, no. 1 (February 28, 2018): 147–57. http://dx.doi.org/10.24329/jurkom.v1i1.21.
Повний текст джерелаАнотація:
Purwokerto is the capital of Banyumas Regency as a growing and developing small tow. Purwokerto has experienced population transformation in terms of both quantity and quality. Based on statistical data can be seen that the population in the city per year 2014 ranged between 292,782 people with an area of 38.58 KM². The increase of population per year is also increasing along with the number of migrant population. This is an opportunity for business people are no exception to the culinary business. Waroenk Ora Umum is one type of culinary business which is quite rapid growth in the city of Purwokerto. Along with the current milenal era, it is necessary to further explore the marketing strategy of targeted marketing communications. And digital marketing is one strategy that has enough impact to increase the number of consumer culinary business in this era. This study used qualitative research methods. Data collection is done by observation, documentation, and interview. The results show that Waroenk Ora Umum Purwokerto has utilized digital marketing strategy which is also balanced with other marketing strategies.
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Yau, Her-Terng, Yu-Chi Pu, and Simon Cimin Li. "An FPGA-Based PID Controller Design for Chaos Synchronization by Evolutionary Programming." Discrete Dynamics in Nature and Society 2011 (2011): 1–11. http://dx.doi.org/10.1155/2011/516031.
Повний текст джерелаАнотація:
This paper is concerned with the design of a field programmable gate arrays- (FPGAs-) based digital proportional-integral-derivative (PID) controller for synchronization of a continuous chaotic model. By using the evolutionary programming (EP) algorithm, optimal control gains in PID-controlled chaotic systems are derived such that a performance index of integrated absolute error (IAE) is as minimal as possible. To verify the system performance, basic electronic components, including OPA resistor and capacitor elements, were used to implement the chaotic Sprott circuits, and FPGA technology was used to implement the proposed digital PID controller. Numerical and experimental results confirmed the effectiveness of the proposed synchronization procedure.
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Wan Yaacob, Wan Mohd Yusoff, Nur Haryani Zakaria, and Zahurin Mat Aji. "Identification of Factors Contributing to Online Game Addiction among Adolescents." Journal of Information and Communication Technology 20, No.4 (September 27, 2021): 565–97. http://dx.doi.org/10.32890/jict2021.20.4.5.
Повний текст джерелаАнотація:
Nowadays, there are growing views of potentially addictive behaviors such as digital addiction, especially Online Game Addiction (OGA). This study argues that all types of addictions are related to common components, such as salience, mood modification, tolerance, withdrawal, conflict, relapse, and problems. Despite the plethora of online game consequences, there is no standard or benchmark used to classify between addicted and non-addicted users. Therefore, this study is organized to identify the factors that contribute to OGA and examine the level of OGA especially among adolescents by utilizing the Online Game Addiction Scale (OGAS). Using the same scale, the adolescents were classified into addicted and non-addicted categories. Driven by previous studies of conventional game addiction, this study adopted all the distinct common components to measure seven underlying criteria related to OGA. The dimensional structure of the scale was analyzed based on the samples of adolescents among students of higher learning institutions (HLI) in Northern Malaysia. Data were collected from 389 participants who responded to an online survey. Based on OGAS, 35 percent of the participants were found to be addicted to online games. In addition, the findings demonstrated good concurrent validity as shown by the coherent associations between the time spent on playing games and the category of the games. This study contributes to the identification of factors that influence OGA among adolescents, which are significant in preventing the occurrence of other behavioral issues such as insecure cyber and emotional behaviors.
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Vrana, Justin D., Nuttada Panpradist, Nikki Higa, Daisy Ko, Parker Ruth, Ruth Kanthula, James J. Lai, et al. "Implementation of an interactive mobile application to pilot a rapid assay to detect HIV drug resistance mutations in Kenya." PLOS Global Public Health 2, no. 2 (February 16, 2022): e0000185. http://dx.doi.org/10.1371/journal.pgph.0000185.
Повний текст джерелаАнотація:
Usability is an overlooked aspect of implementing lab-based assays, particularly novel assays in low-resource-settings. Esoteric instructions can lead to irreproducible test results and patient harm. To address these issues, we developed a software application based on “Aquarium”, a laboratory-operating system run on a computer tablet that provides step-by-step digital interactive instructions, protocol management, and sample tracking. Aquarium was paired with a near point-of-care HIV drug resistance test, “OLA-Simple”, that detects mutations associated with virologic failure. In this observational study we evaluated the performance of Aquarium in guiding untrained users through the multi-step laboratory protocol with little supervision. To evaluate the training by Aquarium software we conducted a feasibility study in a laboratory at Coptic Hope Center in Nairobi, Kenya. Twelve volunteers who were unfamiliar with the kit performed the test on blinded samples (2 blood specimens; 5 codons/sample). Steps guided by Aquarium included: CD4+ T-Cell separation, PCR, ligation, detection, and interpretation of test results. Participants filled out a short survey regarding their demographics and experience with the software and kit. None of the laboratory technicians had prior experience performing CD4+ separation and 7/12 had no experience performing laboratory-based molecular assays. 12/12 isolated CD4+ T cells from whole blood with yields comparable to isolations performed by trained personnel. The OLA-Simple workflow was completed by all, with genotyping results interpreted correctly by unaided-eye in 108/120 (90%) and by software in 116/120 (97%) of codons analyzed. In the surveys, participants favorably assessed the use of software guidance. The Aquarium digital instructions enabled first-time users in Kenya to complete the OLA-simple kit workflow with minimal training. Aquarium could increase the accessibility of laboratory assays in low-resource-settings and potentially standardize implementation of clinical laboratory tests.
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Rackwitz, Maike, Thurid Hustedt, and Gerhard Hammerschmid. "Digital transformation: From hierarchy to network-based collaboration? The case of the German “Online Access Act”." der moderne staat – Zeitschrift für Public Policy, Recht und Management 14, no. 1-2021 (June 15, 2021): 101–20. http://dx.doi.org/10.3224/dms.v14i1.05.
Повний текст джерелаАнотація:
To unlock the full potential of ICT-related public sector innovation and digital transformation, governments must embrace collaborative working structures and leadership, is commonly argued. However, little is known about the dynamics of such collaborations in contexts of hierarchy, silo cultures, and procedural accountability. A widely voiced but empirically insufficiently substantiated claim is that bringing cross-cutting digital endeavours forward requires more lateral, network-based approaches to governance beyond traditional Weberian ideals. We test this claim by shedding light on three distinct challenges (complexity, risk, and power imbalance) encountered when implementing the specific collaborative case of the German Online Access Act (OAA) and by examining how they have been addressed in institutional design and leadership. Our analysis, which combines desk research and semi-structured expert interviews, reveals that flexible, horizontal approaches are on the rise. Taking a closer look, however, vertical coordination continues to serve as complementary means to problem-solving capability.
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Obayemi, O. E., and O. O. Komolafe. "HISTOPATHOLOGY STUDIES OF SELECTED ORGANS OF Hemichromis fasciatus INHABITING IGUN GOLD MINING AND OPA RESERVOIRS, OSUN STATE, NIGERIA: A COMPARATIVE STUDY." Open Journal of Environmental Research (ISSN: 2734-2085) 1, no. 1 (March 10, 2020): 21–32. http://dx.doi.org/10.52417/ojer.v1i1.69.
Повний текст джерелаАнотація:
This study examined the histopathological alterations in the gills, fillet and liver of Hemichromis fasciatus in Igun reservoir (located in an abandoned goldmine area) compared to those of Opa reservoir. Life fish species were collected from Opa and Igun reservoirs and identified in the laboratory. Techniques based on histological analyses were done on the organs and photomicrographs taken using digital binocular compound LED microscope. Epithelial lifting and hypertrophy of lamellae were observed in the gills of H. fasciatus in Opa reservoir and compared to rupture of gill epithelium, rupture of chloride cell, fusion, hyperplasia, curling of lamellae in H. fasciatus of Igun reservoir. The fillet of H. fasciatusin Opa and Igun reservoirs revealed splitting and atrophy of muscle bundles. Also, parasite cyst and necrosis were observed in the fillet of H. fasciatus of Igun reservoir compared to degeneration in muscle bundles in the fish of Opa reservoir. Similarly, the liver of H. fasciatus in Igun and Opa reservoirs showed splitting at the wall of central vein, hepatopancreas and liver cells degeneration. Moreover, nucleus hypertrophy was also identified in the liver of H. fasciatus in Opa reservoir compared to vascular congestion in the central vein, bile duct, portal vein and portal artery of H. fasciatus in Igun reservoir. The study therefore concluded that H. fasciatus specimens in Igun reservoir were histopathologically unhealthy as compared with those of Opa reservoir probably due to the high level of pollution resulting in bioaccumulation of heavy metals in Igun reservoir samples.
Obayemi, O. E | Department of Zoology, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
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Macedo-Cruz, Antonia, Gonzalo Pajares, Matilde Santos, and Isidro Villegas-Romero. "Digital Image Sensor-Based Assessment of the Status of Oat (Avena sativa L.) Crops after Frost Damage." Sensors 11, no. 6 (June 3, 2011): 6015–36. http://dx.doi.org/10.3390/s110606015.
Повний текст джерела
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Laux, Johann, Sandra Wachter, and Brent Mittelstadt. "Neutralizing online behavioural advertising: Algorithmic targeting with market power as an unfair commercial practice." Common Market Law Review 58, Issue 3 (June 1, 2021): 719–50. http://dx.doi.org/10.54648/cola2021048.
Повний текст джерелаАнотація:
Online behavioural advertising (OBA) relies on inferential analytics to target consumers based on data about their online behaviour. While the technology can improve the matching of adverts with consumers’ preferences, it also poses risks to consumer welfare as consumers face offer discrimination and the exploitation of their cognitive errors. The technology’s risks are exacerbated by the market power of ad intermediaries. This article shows how the Unfair Commercial Practices Directive (UCPD) can protect consumers from behavioural exploitation by incorporating market power analysis. Drawing on current research in economic theory, it argues for applying a stricter average consumer test if the market for ad intermediaries is highly concentrated. This stricter test should neutralize negative effects of behavioural targeting on consumer welfare. The article shows how OBA can amount to a misleading action and/or a misleading omission under Articles 6 and 7 UCPD, as well as an aggressive practice under Article 8 UCPD. It further considers how the recent legislative proposals by the European Commission to enact a Digital Markets Act (DMA) and a Digital Services Act (DSA) may interact with the UCPD and the suggested stricter average consumer test.
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Li, Yan, and Yuhua Guo. "Research on the Strategy of Smart Classroom Construction Based on Teachers’ Data Literacy." SHS Web of Conferences 123 (2021): 01017. http://dx.doi.org/10.1051/shsconf/202112301017.
Повний текст джерелаАнотація:
The rapid development of quality education and the proposal of the theme of reducing educational burden under the new situation have further promoted the pace of curriculum teaching reform. Exploring the development strategy ofa hybrid teaching model based on knowledge graphs with quality education as the core has important educational practical significance. In the digital age, smart classroom is the inevitable trend of the development of digital technology. Teachers’ data literacy reflects the requirements of intelligent classroom for teachers. This paper discusses the connotation of smart classroom and the construction strategy of smart classroom based on Teachers’ data literacy, which helps to improve teachers’ data literacy, build smart classroom, promote the in-depth integration of teachers’ data literacy and smart classroom construction, and provide reference for the development of teachers’ data literacy and the teaching practice of smart classroom.
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Lin, Wen-Yen, Wen-Cheng Chou, Tsu-Hui Shiao, Guang-Ming Shiao, Chin-Shan Luo, and Ming-Yih Lee. "Realization of a CORDIC-Based Plug-In Accelerometer Module for PSG System in Head Position Monitoring for OSAS Patients." Journal of Healthcare Engineering 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/4728187.
Повний текст джерелаАнотація:
Overnight polysomnography (PSG) is currently the standard diagnostic procedure for obstructive sleep apnea (OSA). It has been known that monitoring of head position in sleep is crucial not only for the diagnosis (positional sleep apnea) but also for the management of OSA (positional therapy). However, there are no sensor systems available clinically to hook up with PSG for accurate head position monitoring. In this paper, an accelerometer-based sensing system for accurate head position monitoring is developed and realized. The core CORDIC- (COordinate Rotation DIgital Computer-) based tilting sensing algorithm is realized in the system to quickly and accurately convert accelerometer raw data into the desired head position tilting angles. The system can hook up with PSG devices for diagnosis to have head position information integrated with other PSG-monitored signals. It has been applied in an IRB test in Taipei Veterans General Hospital and has been proved that it can meet the medical needs of accurate head position monitoring for PSG diagnosis.
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Evans, Andrew J., Mohamed E. Salama, Walter H. Henricks, and Liron Pantanowitz. "Implementation of Whole Slide Imaging for Clinical Purposes: Issues to Consider From the Perspective of Early Adopters." Archives of Pathology & Laboratory Medicine 141, no. 7 (April 25, 2017): 944–59. http://dx.doi.org/10.5858/arpa.2016-0074-oa.
Повний текст джерелаАнотація:
Context.— There is growing interest in the use of digital pathology, especially whole slide imaging, for diagnostic purposes. Many issues need to be considered when incorporating this technology into a clinical laboratory. The College of American Pathologists (CAP) established a Digital Pathology Committee to support the development of CAP programs related to digital pathology. One of its many initiatives was a panel discussion entitled “Implementing Whole-Slide Imaging for Clinical Use: What to Do and What to Avoid,” given for 3 years at the CAP annual meetings starting in 2014. Objectives.— To review major issues to consider when implementing whole slide imaging for clinical purposes as covered during the panel discussion. Design.— The views expressed and recommendations given are based primarily on the personal experience of the authors as early adopters of this technology. It is not intended to be an exhaustive review of digital pathology. Results.— Implementation is best approached in phases. Early efforts are directed toward identifying initial clinical applications and assembling an implementation team. Scanner selection should be based on intended use and budget. Recognizing pathologist concerns over the use of digital pathology for diagnostic purposes, ensuring adequate training, and performing appropriate validation studies will enhance adoption. Once implemented, the transition period from glass slide to image-based diagnostics will be associated with challenges, especially those related to a hybrid glass slide–digital slide workflow. Conclusions.— With appropriate preparation, planning, and stepwise implementation, whole slide imaging can be used safely and reliably for frozen sections, consultation, quality assurance, and primary diagnosis.
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Trevisan, Lucas Renato, Lisiane Brichi, Tamara Maria Gomes, and Fabrício Rossi. "Estimating Black Oat Biomass Using Digital Surface Models and a Vegetation Index Derived from RGB-Based Aerial Images." Remote Sensing 15, no. 5 (February 28, 2023): 1363. http://dx.doi.org/10.3390/rs15051363.
Повний текст джерелаАнотація:
Responsible for food production and industry inputs, agriculture needs to adapt to worldwide increasing demands and environmental requirements. In this scenario, black oat has gained environmental and economic importance since it can be used in no-tillage systems, green manure, or animal feed supplementation. Despite its importance, few studies have been conducted to introduce more accurate and technological applications. Plant height (H) correlates with biomass production, which is related to yield. Similarly, productivity status can be estimated from vegetation indices (VIs). The use of unmanned aerial vehicles (UAV) for imaging enables greater spatial and temporal resolutions from which to derive information such as H and VI. However, faster and more accurate methodologies are necessary for the application of this technology. This study intended to obtain high-quality digital surface models (DSMs) and orthoimages from UAV-based RGB images via a direct-to-process means; that is, without the use of ground control points or image pre-processing. DSMs and orthoimages were used to derive H (HDSM) and VIs (VIRGB), which were used for H and dry biomass (DB) modeling. Results showed that HDSM presented a strong correlation with actual plant height (HREF) (R2 = 0.85). Modeling biomass based on HDSM demonstrated better performance for data collected up until and including the grain filling (R2 = 0.84) and flowering (R2 = 0.82) stages. Biomass modeling based on VIRGB performed better for data collected up until and including the booting stage (R2 = 0.80). The best results for biomass estimation were obtained by combining HDSM and VIRGB, with data collected up until and including the grain filling stage (R2 = 0.86). Therefore, the presented methodology has permitted the generation of trustworthy models for estimating the H and DB of black oats.
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Castro, Gabriel, and Grover Zurita. "Applications of Operational Modal Analysis in Gearbox and Induction Motor, Based on Random Decrement Technique and Enhanced Ibrahim Time Method." Applied Sciences 12, no. 10 (May 23, 2022): 5284. http://dx.doi.org/10.3390/app12105284.
Повний текст джерелаАнотація:
There have been steadily growing requirements from the academia and industry, demanding non-invasive methods and reliable measurement systems of research devoted to operational mode analysis (OMA). Due to the simplicity of performing only structures surface vibration measurements, OMA is frequently applied in machine fault diagnosis (MFD) and structure health monitoring (SHM). OMA can handle big structures, such as bridges, buildings, machines, etc. However, there is still an open question: how to properly handle the harmonic effects of rotating components and the difficulty of closely estimating space modes are still a nightmare to deal with. Therefore, the main objective of this paper is to identify the structure of natural frequencies by the regeneration of frequency response functions (FRFs) for complex structures based on OMA. The novelty of our approach is to use the random decrement technique (RDT), correlation function estimation (CFE), and enhanced Ibrahim time method (EITM) to overcome OMA’s difficulties and limitations. To reduce further rotational harmonics effects, gear mesh and side band frequencies, digital signal processing techniques based on notching filters, and liftering analysis techniques were also used. All the experiments were performed at the laboratory test rig and conducted by using three accelerometers, one impedance hammer, one force sensor, and one data acquisition board. To reduce data’s variabilities, each test was measured three times for 5 min. The data sampling frequency for all the experiments was 25.6 kHz. To validate the proposed methodology, extensive OMA tests were performed for the generation of FRFs. The measured objects were a steel bar, induction motor, and gearbox. Five structural natural frequencies for the induction motor and eight structural natural frequencies for the gearbox were generated, respectively.