scholarly journals Tunable Optical Diffusers Based on the UV/Ozone-Assisted Self-Wrinkling of Thermal-Cured Polymer Films

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5820
Author(s):  
Shulan Jiang ◽  
Yong Tan ◽  
Yong Peng ◽  
Jiang Zhao
Keyword(s):  
Polymer Films ◽  
Tensile Strain ◽  
Low Cost ◽  
Rapid Development ◽  
Incident Light ◽  
Cost Effective ◽  
Uniaxial Tensile ◽  
Initial State ◽  
Wrinkle Structures ◽  
Uv Ozone

Tunable optical diffusers have attracted attention because of the rapid development of next generation stretchable optoelectronics and optomechanics applications. Flexible wrinkle structures have the potential to change the light path and tune the diffusion capability, which is beneficial to fabricate optical diffusers. The generation of wrinkles usually depends on an external stimulus, thus resulting in complicated fabricating equipment and processes. In this study, a facile and low-cost method is proposed to fabricate wrinkle structures by the self-wrinkling of thermal-cured polymer for tunable optical diffusers. The uncured polydimethylsiloxane (PDMS) precursors were exposed to UV/ozone to obtain hard silica layers and then crosslinked via heating to induce the wrinkle patterns. The wrinkle structures were demonstrated as strain-dependent tunable optical diffusers and the optical diffusion of transmitted light via the deformable wrinkle structures was studied and adjusted. The incident light isotropically diffused through the sample at the initial state. When the wrinkle structures deformed, it showed a more pronounced isotropic optical diffusion with uniaxial tensile strain. The optical diffusion is anisotropical with a further increase in uniaxial tensile strain. The proposed method of fabricating wrinkles by UV/ozone-assisted self-wrinkling of thermal-cured polymer films is simple and cost-effective, and the obtained structures have potential applications in tunable optical diffusers.

A cost-effective programmable SoC for network security using Xilinx Spartan 3AN FPGA

2014 ◽  
Vol 12 (2) ◽  
pp. 280-291
Author(s):  
Wael M. El-Medany
Keyword(s):  
Network Security ◽  
Hardware Implementation ◽  
Low Cost ◽  
Rapid Development ◽  
Main Idea ◽  
Logic Gates ◽  
Cost Effective ◽  
Low Complexity ◽  
Data Encryption ◽  
Content Type

Purpose – With the rapid development in wired and wireless networks, the demand for network security system is rising rapidly due to more and more new applications introduced. The main factors that rate the encryption algorithms are its ability to secure and protect data against attacks, its speed and efficiency. In this paper, a reconfigurable network security design using multi-mode data encryption standard (DES) algorithm has been implemented with low complexity and low cost, which will also reduce the speed. The paper aims to discuss these issues. Design/methodology/approach – The design can be easily reconfigured to 3DES (triple DES) which is more secure and more powerful in encryption and decryption, as one of the trick in designing 3DES is to reuse three instances of DES. The design can be used for wired and wireless network applications, and it has been described using VHDL and implemented in a reconfigurable Programmable System-on-Chip (PSoC). The hardware implementation has targeted Xilinx Spartan XC3S700-AN FPGA device. Findings – The main idea of reducing the complexity for the hardware implementation is by optimizing the number of logic gates and LUTs of the design. The number of logic gates can be decreased by changing the way of writing the VHDL code and by optimizing the size of the chip. Originality/value – The design has been tested in simulation and hardware levels, and the simulation results and performance are discussed.

scholarly journals Fabrication and Characterization of Near Infrared Molybdenum Disulfide/Silicon Heterojunction Photodetector by Drop Casting Method

2021 ◽  
Author(s):  
Haroon Rashid ◽  
Norhana Arsad ◽  
Harith Ahmad ◽  
Ahmad Ashrif A. Bakar ◽  
Mamun Ibne Reaz
Keyword(s):  
Molybdenum Disulfide ◽  
Near Infrared ◽  
Film Growth ◽  
Low Cost ◽  
Incident Light ◽  
Cost Effective ◽  
Optoelectronic Device ◽  
Casting Method ◽  
Incident Laser Power ◽  
Device Applications

In this work, a highly efficient, molybdenum disulfide (MoS2) based near infrared (NIR) heterojunction photodetector is fabricated on a Si substrate using a cost-effective and simple drop casting method. A non-stoichiometric and inhomogeneous MoS2 layer with a S/Mo ratio of 2.02 is detected using energy dispersive X-ray spectroscopy and field emission scanning electron microscope analysis. Raman shifts are noticed at 382.42 cm-1 and 407.97 cm-1, validating MoS2 thin film growth with a direct bandgap of 2.01 eV. The fabricated n-MoS2/p-Si photodetector is illuminated with a 785 nm laser at different intensities, and demonstrate the ability of the photodetector to work in both regions, the forward biased and reverse biased from above 1.5 V and less than -1.0 V. The highest responsivity, R is calculated to be 0.52 A/W while the detectivity D* is 4.08 x 10^10 Jones for an incident light intensity of 9.57 mW/cm2. The minimum rise and fall times are calculated as 1.77 ms and 1.31 ms for an incident laser power of 9.57 mW/cm^2 and 6.99 mW/cm^2 respectively at a direct current bias voltage of 10 V. The demonstrated results are promising for the low-cost fabrication of a thin MoS2 film for photonics and optoelectronic device applications.

Strain and Photovoltaic Sensitivities of Dumbbell-Shape GNR-Base Sensors

2019 ◽  
Author(s):  
Jowesh Avisheik Goundar ◽  
Takuya Kudo ◽  
Qinqiang Zhang ◽  
Ken Suzuki ◽  
Hideo Miura
Keyword(s):  
Vapor Deposition ◽  
Tensile Strain ◽  
Incident Light ◽  
Chemical Vapor ◽  
Strain Sensors ◽  
Gauge Factor ◽  
Uniaxial Tensile ◽  
Incident Light Intensity ◽  
Highly Sensitive ◽  
Electronic Behavior

Abstract The area-arrayed dumbbell-shape Graphene Nano-Ribbons (GNRs) were fabricated by using chemical vapor deposition and photolithography technologies. The electronic behavior of the fabricated GNR-FET structure was evaluated for its photonic properties with an incident light intensity of 1-mW. The 200-nm wide GNRs structure showed metallic properties, while those with the width of 40 nm showed semiconductive properties as was expected. The light-induced photocurrent was observed in all the fabricated GNRs structures. The average photocurrent observed in the 2-mm wide graphene structure was 3.3 A/m2 and that observed in the 40-nm wide area-arrayed GNRs structure was 261 A/m2, respectively. Based on this photocurrent, the external photosensitivity of the 40-nm wide GNRs structure was about 2.6 × 105 A/W.m2 and this value was much larger than that of conventional Si-base solar cells. In addition, the effect of strain on the resistivity of GNRs was measured. Uniaxial tensile strain was applied to the area-arrayed GNRs structures with the width from 200 nm to 40 nm. The gauge factor obtained from the GNRs with the width wider than 100 nm was about 3, and that with the width of 40 nm was about 160. Therefore, highly-sensitive strain sensors can be realized by using GNRs thinner than 70 nm.

scholarly journals A Low-Cost Terahertz Camera

2019 ◽  
Vol 9 (12) ◽  
pp. 2531 ◽  
Author(s):  
François Blanchard ◽  
Joel Edouard Nkeck ◽  
Dominique Matte ◽  
Riad Nechache ◽  
David G. Cooke
Keyword(s):  
Electromagnetic Waves ◽  
Low Cost ◽  
Rapid Development ◽  
Cost Effective ◽  
Night Vision ◽  
Thz Imaging ◽  
Dynamic Background ◽  
Imaging Device ◽  
Simple Modification ◽  
Wide Range

Cost effective imaging is required for a wide range of scientific and engineering applications. For electromagnetic waves in the terahertz (THz) frequency range, a key missing element that has prevented widespread applications in this spectral range is an inexpensive and efficient imaging device. In recent years, vanadium oxide based thermal sensors have rapidly entered the market for night vision capability. At the same time, sensors based on this technology have been applied to the THz domain, but with two orders of magnitude larger pricing range. Here we show that, with a simple modification, a commercially available thermal imaging camera can function as a THz imaging device. By comparing a commercially available THz camera and this low-cost device, we identify the main sensitivity difference is not attributed to anything intrinsic to the devices, but rather to the analog-to-digital converter and dynamic background subtraction capability. This demonstration of a low-cost THz camera may aid in the rapid development of affordable THz imaging solutions for industrial and scientific applications.

Reliability, Availability, Maintainability (RAM) for Wind Turbines

2017 ◽  
Author(s):  
Nikhil Kumar ◽  
David Rogers ◽  
Thomas D. Burnett ◽  
Eric Sullivan ◽  
Martin Gascon
Keyword(s):  
Wind Turbines ◽  
Low Cost ◽  
Rapid Development ◽  
Turbine Blades ◽  
Wind Farms ◽  
Cost Effective ◽  
Wind Turbine Blades ◽  
Unique Challenge ◽  
Operational Risks ◽  
Reliability And Availability

Wind based electric generation is one of the fastest growing energy sources in the world. With rapid development of wind farms, many challenges have emerged with respect to the reliability and availability of the in-service equipment. Additionally, with increasing size of wind turbine blades, both onshore and offshore, the serviceability and maintainability of the equipment poses its own unique challenge. There is also an inherent risk from the economics of energy production, which dictates that low-cost manufacturing methods are employed to produce cost-effective machines. In our experience, there are additional risks associated with supply chains and limited availability and understanding of damage mechanisms and reliability data of the myriad manufacturers and models of turbines, blade design and associated equipment. Failure of different components results in different outage times and therefore impact operational and maintenance (O&M) costs in different ways. Achieving high availability targets requires a robust O&M plan. The authors will highlight operational risks of large wind turbines and methodologies to improve reliability and availability for wind farms.

ASSESSMENT OF THE PLATELET COUNT IN THE PREGNANT WOMEN IN IGIMS, PATNA, BIHAR

2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Tanwi Singh ◽  
Anshuman Sinha
Keyword(s):  
Platelet Count ◽  
Pregnant Women ◽  
Screening Test ◽  
Low Cost ◽  
Medical Science ◽  
Cost Effective ◽  
Platelet Indices ◽  
Increased Risk ◽  
Low Platelet Count ◽  
Severity Of The Disease

The major risk associated with low platelet count in pregnancy is the increased risk of bleeding during the childbirth or post that. There is an increased blood supply to the uterus during pregnancy and the surgical procedure requires cutting of major blood vessels. Women with thrombocytopenia are at increased risk of losing excessive blood. The risk is more in case of caesarean delivery as compared to vaginal delivery. Hence based on above findings the present study was planned for Assessment of the Platelet Count in the Pregnant Women in IGIMS, Patna, Bihar. The present study was planned in Department of Pathology, Indira Gandhi Institute of Medical Science, Patna, Bihar, India. The present study was planned from duration of January 2019 to June 2019. In the present study 200 pregnant females samples received for the platelet estimation were enrolled in the present study. Clinically platelet indices can be a useful screening test for early identification of preeclampsia and eclampsia. Also platelet indices can assess the prognosis of this disease in pregnant women and can be used as an effective prognostic marker because it correlates with severity of the disease. Platelet count is a simple, low cost, and rapid routine screening test. Hence the data generated from the present study concludes that platelet count can be used as a simple and cost effective tool to monitor the progression of preeclampsia, thereby preventing complications to develop during the gestational period. Keywords: Platelet Count, Pregnant Women, IGIMS, Patna, Bihar, etc.

Janus – A New Approach to Air Combat Pilot Training

2019 ◽  
Vol 2019 (4) ◽  
pp. 7-22
Author(s):  
Georges Bridel ◽  
Zdobyslaw Goraj ◽  
Lukasz Kiszkowiak ◽  
Jean-Georges Brévot ◽  
Jean-Pierre Devaux ◽  
...  
Keyword(s):  
Low Cost ◽  
Cost Effective ◽  
High Energy ◽  
Training System ◽  
Embedded Sensors ◽  
Pilot Training ◽  
New Approach ◽  
Combat Aircraft ◽  
Air Combat ◽  
The Cost

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.

Motivating Compliance: Firm Response to Mandatory Disclosure Policies

2018 ◽  
Vol 32 (2) ◽  
pp. 103-119
Author(s):  
Colleen M. Boland ◽  
Chris E. Hogan ◽  
Marilyn F. Johnson
Keyword(s):  
Conflict Of Interest ◽  
Low Cost ◽  
Cost Effective ◽  
Data Availability ◽  
Policy Adoption ◽  
Future Research ◽  
Regulated Firms ◽  
Firm Response ◽  
Disclosure Rules ◽  
The Impact

SYNOPSIS Mandatory existence disclosure rules require an organization to disclose a policy's existence, but not its content. We examine policy adoption frequencies in the year immediately after the IRS required mandatory existence disclosure by nonprofits of various governance policies. We also examine adoption frequencies in the year of the subsequent change from mandatory existence disclosure to a disclose-and-explain regime that required supplemental disclosures about the content and implementation of conflict of interest policies. Our results suggest that in areas where there is unclear regulatory authority, mandatory existence disclosure is an effective and low cost regulatory device for encouraging the adoption of policies desired by regulators, provided those policies are cost-effective for regulated firms to implement. In addition, we find that disclose-and-explain regulatory regimes provide stronger incentives for policy adoption than do mandatory existence disclosure regimes and also discourage “check the box” behavior. Future research should examine the impact of mandatory existence disclosure rules in the year that the regulation is implemented. Data Availability: Data are available from sources cited in the text.

GeSn Lasers with Uniaxial Tensile Strain in the Gain Medium

2019 ◽  
Author(s):  
Mathieu Bertrand ◽  
Francesco Armand Pilon ◽  
Vincent Reboud ◽  
Hans Sigg ◽  
Quang-Minh Thai ◽  
...  
Keyword(s):  
Tensile Strain ◽  
Gain Medium ◽  
Uniaxial Tensile

Azo (Hydrazone) pigments: general principles

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Robert Christie
Keyword(s):  
High Performance ◽  
Metal Salt ◽  
Low Cost ◽  
Cost Effective ◽  
Precipitation Process ◽  
Ambient Temperatures ◽  
Technical Performance ◽  
Chemical Structures ◽  
General Chemical ◽  
Physical Form

Abstract This paper presents an overview of the general chemical principles underlying the structures, synthesis and technical performance of azo pigments, the dominant chemical class of industrial organic pigments in the yellow, orange, and red shade areas, both numerically and in terms of tonnage manufactured. A description of the most significant historical features in this group of pigments is provided, starting from the discovery of the chemistry on which azo colorants are based by Griess in the mid-nineteenth century, through the commercial introduction of the most important classical azo pigments in the early twentieth century, including products known as the Hansa Yellows, β-naphthol reds, including metal salt pigments, and the diarylide yellows and oranges, to the development in the 1950s and 1960s of two classes of azo pigments that exhibit high performance, disazo condensation pigments and benzimidazolone-based azo pigments. A feature that complicates the description of the chemical structures of azo pigments is that they exist in the solid state as the ketohydrazone rather than the hydroxyazo form, in which they have been traditionally been illustrated. Numerous structural studies conducted over the years on an extensive range of azo pigments have demonstrated this feature. In this text, they are referred to throughout as azo (hydrazone) pigments. Since a common synthetic procedure is used in the manufacture of virtually all azo (hydrazone) pigments, this is discussed in some detail, including practical aspects. The procedure brings together two organic components as the fundamental starting materials, a diazo component and a coupling component. An important reason for the dominance of azo (hydrazone) pigments is that they are highly cost-effective. The syntheses generally involve low cost, commodity organic starting materials and are carried out in water as the reaction solvent, which offers obvious economic and environmental advantages. The versatility of the approach means that an immense number of products may be prepared, so that they have been adapted structurally to meet the requirements of many applications. On an industrial scale, the processes are straightforward, making use of simple, multi-purpose chemical plant. Azo pigments may be produced in virtually quantitative yields and the processes are carried out at or below ambient temperatures, thus presenting low energy requirements. Finally, provided that careful control of the reaction conditions is maintained, azo pigments may be prepared directly by an aqueous precipitation process that can optimise physical form, with control of particle size distribution, crystalline structure, and surface character. The applications of azo pigments are outlined, with more detail reserved for subsequent papers on individual products.

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