Enclosure Box Research Articles

The Development of a Novel Nitrate Portable Measurement System Based on a UV Paired Diode-Photodiode.

Nitrates can cause severe ecological imbalances in aquatic ecosystems, with considerable consequences for human health. Therefore, monitoring this inorganic form of nitrogen is essential for any water quality management structure. This research was conducted to develop a novel Nitrate Portable Measurement System (NPMS) to monitor nitrate concentrations in water samples. NPMS is a reagent-free ultraviolet system developed using low-cost electronic components. Its operation principle is based on the Beer-Lambert law for measuring nitrate concentrations in water samples through light absorption in the spectral range of 295-315 nm. The system is equipped with a ready-to-use ultraviolet sensor, light emission diode (LED), op-amp, microcontroller, liquid crystal display, quartz cuvette, temperature sensor, and battery. All the components are assembled in a 3D-printed enclosure box, which allows a very compact self-contained equipment with high portability, enabling field and near-real-time measurements. The proposed methodology and the developed instrument were used to analyze multiple nitrate standard solutions. The performance was evaluated in comparison to the Nicolet Evolution 300, a classical UV-Vis spectrophotometer. The results demonstrate a strong correlation between the retrieved measurements by both instruments within the investigated spectral band and for concentrations above 5 mg NO3-/L.

OPTIMASI MULTI PARAMETER MESIN 3D PRINTER FDM UNTUK MATERIAL THERMOPLASTIC POLYURETHANE GUNA MENGHASILKAN ERROR DIMENSI TERKECIL MENGGUNAKAN METODE 2K FACTORIAL DESIGN

Fused Deposition Modeling or FDM is a 3D printing technology that is commonly used in manufacturing processes based on Additive Manufacturing Technology. One of the materials that can be used on FDM machines is thermoplastic polyurethane (TPU). One measure of the quality of printed results is the machine's accuracy in producing workpieces that have the smallest possible dimensional error. So this research aims to obtain the printing parameters that have the most influence on print results and find out the optimal combination of printing process parameters on the machine to produce the smallest dimensional error for TPU material. The design of experiment method used is 2k factorial design using 4 process parameters, 2 levels and 3 responses. The parameters used are nozzle temperature, print speed, fill density, and enclosure box. The optimization results obtained an optimal combination of printing process parameters to produce the smallest dimensional error, namely nozzle temperature of 210°C, print speed of 30 mm/s, fill density of 100%, and not using an enclosure box.

Image Processing-Based System for Apple Sorting

This study sheds light on the evolution of the agricultural industry and highlights advances in production area. The salient recognition of fruit size and shape as critical quality parameters underscores the significance of the research. In response to this challenge, the research introduces specialized image processing techniques designed to streamline the sorting of apples in agricultural settings, specifically emphasizing accurate apple width estimation. A purpose-built machine was designed, featuring an enclosure box housing a cost-effective camera for the vision system and a chain conveyor for classifying Malus domestica Borkh kind apples. These goals were successfully achieved by implementing image preprocessing, segmentation, and measurement techniques to facilitate sorting. The proposed methodology classifies apples into three distinct classes, attaining an impressive accuracy of 94% in Class 1, 92% in Class 2, and 86% in Class 3. This represents an efficient and economical solution for apple classification and size estimation, promising substantial enhancements to sorting processes and pushing the boundaries of automation in the agricultural sector.

Experimental investigation work on a solar cavity collector

Solar collector is a device that converts the solar radiation into some useful heat energy. The conventional solar collector often used globally to heat water is a Flat Plate Solar Collector (FPC) configuration. Solar Cavity Collector (SCC) is a newly designed modern version of an FPC. In order to improve the performance characteristics of FPC, it has been modified with necessary design changes and termed as cavity collector. Cavity type collectors are more familiar with Fresnel and concentrating type collectors but they have been implemented for the development of FPC. A tubular absorber cum receiver which is 6.35 mm in radius with black colour paint coated onto it has been concentrically positioned in the cylindrical contour. SCC comprises combinations of 5 individual cavities and receivers. Five such cavities and receivers are fabricated at first, and they have been placed concentrically in a 50 × 50 square shaped metal enclosure box. A performance test has been conducted on SCC with the following parameters:(1) Receiver materials of both aluminium and copper;(2) changing the mode of flow as parallel and serpentine types;(3) angle of tilt of the whole setup of SCC;(4) SCC has been packed with metal scrap chips and pebbles bed;(5) cavity cover materials of both mild steel (MS) and galvanized iron (G.I) have been tested. The result shows that the usage of copper as a receiver material performs better than the aluminium. SCC with the usage of pebbles has an improvement in energy transfer of about 3 %. The methodology with improved heat transfer characteristics can be achieved by SCC and it can be effectively used during cloudy and partly cloudy days where the intermittence in solar energy is inexorable.

Design and development of frequency tuneable vibration based piezoelectric energy harvester

This paper presents the design and development of manual frequency tuneable energy harvester. The energy harvester consists of beam, piezoelectric materials, proof mass, charging circuit, storage device and enclosure box. The design of beam and proof mass was made using the output of previous work and other parts were designed in this work. The energy harvester was developed based on the design and placed into the enclosure box. The fabricated model was tested to know the performance of energy harvester by analysing the output voltage, current, power and charging time of the battery. The distance of proof mass was varied from the fixed end of the cantilever beam to tune the frequency of energy harvester. From the experiment, it was found that the proof mass of energy harvester at 115 mm produced 88.77% more power compared to the proof mass placed at 85 mm from the fixed end. The operating range of energy harvester is about 5 Hz to 30 Hz. The proof mass placed at a distance of 155 mm from the fixed end charge the 60 mAh battery at 65.14% faster compared to the proof mass placed at 85 mm from the fixed end.

Introduction to IEEE Standard 1584: Guide for Performing Arc-Flash Hazard Calculations, 2018 Edition

Since it was first published in 2002, IEEE standard 1584 has been the premier standard for arc-flash hazard arcing current, incident energy, and arc-flash boundary (AFB) calculations for an arc-flash incident. After extensive testing and model development and a validation period, the long-awaited revision of IEEE 1584 has been published. The purpose of this article is to introduce IEEE Standard 1584-2018, IEEE Guide for Performing Arc-Flash Hazard Calculations , to the industry. The model range and the rationale used for parameter selection is discussed for quantities such as voltage, bolted root-mean-square (rms) short circuit current, the gap between conductors, enclosure dimensions, fault duration, working distance, and system frequency. The rationale is provided for the selection of electrode configurations and various enclosure (box) sizes and arrangements. This model is based on more than six times the tests performed for the model used in the 2002 standard. It provides additional modeling of electrode configurations which were not included in the 2002 version. Some guidance on identifying electrode configurations is provided.

Design and Evaluation of Radiated Emission Metamaterial Absorbers

In this paper, mitigation of unwanted radiated electromagnetic emissions from a high-speed system enclosure using metamaterial-based absorbers is investigated. First, the performance of an earlier introduced frequency selective metamaterial absorber is thoroughly evaluated via full-wave simulations and compared with that of a commercial thin microwave absorber. An experimental in-lab test set-up is developed to validate simulation results confirming that a stronger mitigation of radiated emissions is delivered by the proposed absorber. The measured radiated emission patterns closely follow simulated results and confirm better than 5 dB reduction in emissions when the proposed absorber is included in the enclosure box. Simulations with simultaneous excitation of multiple radiation sources inside the box prove the effectiveness of the developed absorber in realistic operational conditions that could include array effects for unintentional radiation sources. A second absorber design is introduced in this paper with improved thermal conductivity while providing emission reduction better than 4.6 dB.

Thermosolutal combined convection in a lid-driven enclosure with time periodic heating and linearly salting

Thermosoutal combined convective flow with mass and energy transport in a lid-driven enclosure box with discrete time periodic heating and linearly varying mass transfer is numerically investigated. The segment of the left wall is heating periodically in time and the right wall is preserved at a lower temperature. The top and bottom walls are thermally insulated. Two different concentrations are imposed along the left and right walls. The mathematical systems are solved by finite volume method. The results are obtained for various values of factors, like, Richardson number, period and amplitude. It is observed that the oscillating frequency of averaged Nusselt number diminishes with raise in the period in the forced and free convection modes. The averaged Sherwood number rises as amplitude raise in the free convection mode. It is also attained that both averaged Sherwood and Nusselt numbers are diminished on raising the Richardson number.

Hyperbolic lens design of local oscillator optics system for electron cyclotron emission imaging on J-TEXT.

An electron cyclotron emission imaging diagnostic system that contains two 16-antenna arrays is being developed on J-TEXT tokamak. In this heterodyne system, the mixers in the front microwave antenna are used to down-convert the electron cyclotron emission to a 2-12 GHz radio frequency. All of the 24 antenna mixers in the individual enclosure box are driven by shining local oscillator (LO) power via launching optics. The previous approach for LO optics was designed with spherical and cylinder lenses, which has limitations such as the inhomogeneity of the energy deposition on different channels and the difficulty of optics alignment. A new generation of LO optics has been designed and applied on J-TEXT with a hyperbolic lens for uniform power deposition across the entire antenna array. The robustness of the optical alignment will be significantly increased with three hyperbolic lenses. Furthermore, the simulation results and robustness analysis of these LO optics are discussed in this paper.

Design of a portable imager for near-infrared visualization of cutaneous wounds.

A portable imager developed for real-time imaging of cutaneous wounds in research settings is described. The imager consists of a high-resolution near-infrared CCD camera capable of detecting both bioluminescence and fluorescence illuminated by an LED ring with a rotatable filter wheel. All external components are integrated into a compact camera attachment. The device is demonstrated to have competitive performance with a commercial animal imaging enclosure box setup in beam uniformity and sensitivity. Specifically, the device was used to visualize the bioluminescence associated with increased reactive oxygen species activity during the wound healing process in a cutaneous wound inflammation model. In addition, this device was employed to observe the fluorescence associated with the activity of matrix metalloproteinases in a mouse lipopolysaccharide-induced infection model. Our results support the use of the portable imager design as a noninvasive and real-time imaging tool to assess the extent of wound inflammation and infection.

MULTI CHAMBER PORTED STEREO SPEAKER

A method and apparatus for a multi-chamber ported stereo speaker is disclosed. The stereo speaker is a single unit with multi-chambers in an enclosure box. The multi chamber ported speaker comprises an enclosure housing a shared acoustic chamber having an external port for allowing air external of the enclosure box to flow into the shared acoustic chamber, and at least two additional chambers comprising a corresponding internal port in each additional chamber for forming an air pass from each additional chamber with the shared chamber, each additional chamber comprising a corresponding driver mounted through a wall of the chamber and enclosure box for forming the ported speaker.

Recognition and Identification of Radiated EMI for Shielding Aperture using Neural Network

This paper presents the method to recognize and identify the difierent type of enclosure with apertures from electromagnetic emission. The square wave generator is fed into the structure-like antenna in the enclosure box. Then the radiated emission from the difierent type of aperture are measured. The thirteen highest amplitude of the radiated emission are fed into an Artiflcial Neural Network input for recognition. The target of the neural network are set in four bits in the digital format. When the training process is flnished the neural network are used for identify the kind of the aperture. The trained neural network are very successfully in identiflcation all kinds of enclosure with apertures. DOI: 10.2529/PIERS060907082540

Observations on the full honeycomb structure of graphite as imaged by atomic force microscopy

Abstract Most atomic force microscopy (AFM) images of highly ordered pyrolytic graphite (HOPG) yield only every other atom with a lattice constant 2.46A. However, its full honeycomb structure, revealing all six carbon atoms of each hexagon, can only be obtained under certain conditions. A particular problem is the large meniscus force generated by a thin condensed layer of water when imaging under ambient conditions. We show that this can be reduced within an enclosure box by self-heating by the piezoelectric scanner and optical system. This was confirmed by obtaining a sequence of consecutive capillary force–distance loops. We have found all six carbon atoms in simultaneous imaging of trace and retrace scan direction although the contrast of the image is inverted according to the direction of the scan. The atomic corrugations at various contact forces were also examined. We observed giant corrugation amplitudes of graphite by AFM, which were as large as 5A. This anomalous effect, together with the invers...

Observation of dipropenyldisulfide and other organic sulfur compounds in the atmosphere of a beech forest with Allium ursinum ground cover

Dipropenyldisulfide, methylpropenyldisulfide, cis-propenylpropyldisulfide, diallylsulfide, dimethyldisulfide and 3-methylthiopropene were detected in the atmosphere of a beech forest with Allium ursinum (broad-leaved garlic) ground cover plants. Furthermore, it was shown that the Allium plants were the source of the organic sulfur compounds. The atmospheric concentrations of the organic sulfur observed on one day in May 1994 in a suburban forest in Vienna ranged from 0.3 to 7.8 ppb S with an average level of 2.9 ppb S. The atmospheric emission rate of organic sulfur species from A. ursinum determined with an enclosure box was the highest ever reported for terrestrial continental plants. The total organic sulfur flux on the average was at least 1 jug g-1h-1 (plant dry weight) or 60 gmgm-2 h-1 (per unit of ground area).

Technical memorandum. Finite-element analysis of shielded microstrip disc resonator

Results are presented of the application of a finite-element method to investigate the influence on the microstrip disc resonator capacitance of the dimensions (R and H) of the conducting enclosure box. Measured values of the resonant frequency for a constructed prototype compare well with theory and show that, to within 1%, the effects of the shielded box can be neglected for R > 3a and H > 2a, where a is the circular patch radius.