Elimination Of Spots Research Articles

Oriented Bi2Te3-based films enabled high performance planar thermoelectric cooling device for hot spot elimination

Film-thermoelectric cooling devices are expected to provide a promising active thermal management solution with the continues increase of the power density of integrated circuit chips and other electronic devices. However, because the microstructure-related performance of thermoelectric films has not been perfectly matched with the device configuration, the potential of planar devices on chip heat dissipation has still not been fully exploited. Here, by liquid Te assistant growth method, highly (00 l) orientated Bi2Te3-based films which is comparable to single crystals are obtained in polycrystal films in this work. The high mobility stem from high orientation and low lattice thermal conductivity resulting from excess Te induced staggered stacking faults leads to high in-plane zT values ~1.53 and ~1.10 for P-type Bi0.4Sb1.6Te3 and N-type Bi2Te3 films, respectively. The planar devices basing on the geometrically designed high orientation films produce a remarkable temperature reduction of ~8.2 K in the hot spot elimination experiment, demonstrating the great benefit of Te assistant growth method for oriented planar Bi2Te3 films and planar devices devices design, and also bring great enlightenment to the next generation active thermal management for integrated circuits.

Quantitative light-induced fluorescence (QLF) for diagnosis of enamel condition during various dental procedures

Relevance. Quantitative light-induced fluorescence (QLF) is widely used to diagnose the enamel condition during various dental interventions and allows for quick, objective and noninvasive assessment of the patient's oral hygiene status and follow-up of enamel de- and remineralization level.Materials and methods. The QLF technique used by the study increases the visual contrast between sound and diseased oral tissues when various (organic) substances in the mouth absorb light of a certain wavelength (different colours) and then re-emit the absorbed energy at a different wavelength. Filtration of illuminating light gives a fluorescent image or a QLF image. In a clinical setting, we used a QLF equipment set, namely, the Q-ray clinical software; Qraycam pro camera for full-arch imaging; Qraypen C intraoral camera; Qscan plus.Results. QLF was an additional tool for a practising dentist or dental hygienist, which allowed for the detection of the pathological process at the earliest stage, assisting in the diagnosis of the dental enamel condition, the detection of plaque without disclosing agents and assessment of its exact amount, contributing to the identification of hidden foci of enamel demineralization and carious lesions, cracks, tartar and oral hygiene evaluation.The analyzed data show the very high efficiency of the performed therapy with the 'R.O.C.S. medical 0+' remineralizing gel. The objective QLF data fully confirm the external elimination of white spots, and their almost complete disappearance is noted.Conclusion. Quantitative light-induced fluorescence and its parameters are essential not only for understanding the effectiveness of the applied techniques for bleaching, microabrasion, remineralization and other manipulations but also for their safety for dental enamel.

Evaluation of the effect from non-capital-intensive measures to reduce the accident rate in road accident concentration spots in major Russian cities

The article is devoted to the analysis of the of non-capital-intensive measures contribution within the framework of the national project “Safe Quality Roads” to the reduction the number of road accident concentration spots in Russian cities with a population of over 1 million people. Based on the spatial analysis, the seasonal nature of changes in the number of accidents was determined. The road accident concentration spots in the cities were identified with QGIS Software Clustering Tools, and their combination with non-capital-intensive measures was established. Using the statistical analysis, Pearson's chi-squared test, classification trees, the non-parametric Mann-Whitney test, the fact of saving/eliminating road accident concentration spots after or without road measures was evaluated. The study made it possible to conclude that measures of The National Program “Safe Quality Roads” do not always lead to the elimination of road accident concentration spots. The effect of the measures in the road accident concentration spots located near intersections and public transport stops is much lower than in other areas.

Experimental study on heat transfer characteristics of separated heat pipe with compact structure for spent fuel pool

A separated heat pipe radiator with compact evaporator section and condenser section was manufactured for the cooling of spent fuel pool. The cold start process shows that the heat pipe can be started smoothly at a given temperature difference. And the effects of various external working conditions on heat transfer capacity and temperature instability of heat pipe are studied, including intake air volume, intake air temperature, and inclination angle. The results show that the radiator can dissipate about 4 kW in the design working condition, and its heat dissipation capacity is further improved in the inclined state. Under the most unfavorable conditions, the water temperature didn’t exceed 90℃, and the temperature distribution inside the water tank was uniform. This separated heat pipe radiator has a positive significance for the decay heat removal and hot spot elimination of the spent fuel pool.

Energy Saving with Zero Hot Spots: A Novel Power Control Approach for Sustainable and Stable Data Centers

Data centers with high energy consumption have become a threat to urban sustainability on electric energy. In contrast, hot spots in a data center are another threat to server stability, which leads to unsafe data storage and service provisioning to urban lives. However, state-of-the-art works cannot ensure sustainability and stability together because they fail to consider them holistically. For example, some existing works eliminate the hot spots by increasing cooling power, which results in lower sustainability. In contrast, others reduce energy consumption by saving the cooling power, which harms stability. Therefore, to balance the hot spot elimination and energy saving through power control remains challenging, this paper proposes a novel power control approach for energy saving with zero hot spots in data centers. Power control works when hot spots appear, or consumed energy is excess. Specifically, we formulated a total consumption minimization problem to characterize and analyze the optimal set points for power control, where the number of hot spots is zero and the energy consumption is low. Adding the interactional penalty models can determine the power control approach when the objective function obtains the optimal solution. We propose a Modified Differential Evolution algorithm (MDE) to solve the function quickly and accurately. It adopts adaptive parameters to reduce the computing time. Meanwhile, it avoids optimal local solutions by changing mutation operations. Further, simulation experiments using our optimal solution demonstrate that energy consumption saves about 13% on average with zero hot spots, compared with three typical approaches.

Endoscopic Imaging Using a Multimode Optical Fibre Calibrated with Multiple Internal References

The interferometric acquisition of the transmission matrix (TM) of a multimode optical fibre (MMF), which is at the heart of multimode fibre-based endoscopic imaging methods, requires using a reference beam. Attempts to use an internal reference, that is to provide the reference in a common pathway geometry through the MMF itself, lead to a speckled reference intensity and consequential occurrence of “blind spots”—locations where insufficient optical power in the reference wave inflicts strong measurement errors. Here we show that combining a relatively small number of TMs, which are measured using different internal references, facilitates a complete elimination of blind spots, and thereby a significant enhancement of the imaging quality.

Endoscopic High Occipital Interhemispheric Transtentorial Approach for Lesions in the Anterosuperior Cerebellum, Upper Fourth Ventricle, and Upper Dorsal Brain Stem

The occipital transtentorial route is considered the most suitable for surgical treatment of lesions arising from the anterosuperior cerebellum, upper fourth ventricle, and upper dorsal brain stem. Therefore, this study examined the feasibility and effectiveness of the endoscopic high occipital interhemispheric transtentorial approach (EHOTA) for lesions in these areas, in achieving results comparable to the endoscopic occipital interhemispheric transtentorial approach (EOTA). EOTA has recently been reported to be an effective procedure for pineal region tumors, having several advantages that include minimal invasiveness with a small entrance limiting the retraction of the occipital lobe, the elimination of blind spots, and the facilitation of fine manipulation due to the bright, magnified panoramic view. By using 30 clinical datasets of venous-phase head computed tomography angiogram, measurements on images were performed and differences between EOTA and EHOTA were identified. In addition, the feasibility of EHOTA was verified with 5 cadaver heads. Although the operative field via EHOTA was considered significantly deeper and less maneuverable than with the procedure via EOTA, beneficial angles for manipulation in the superior cerebellum and the fourth ventricle were obtained in EHOTA, on account of their becoming more obtuse. Using EHOTA, it was possible to reach those regions and effectively manipulate all 10 sides of the 5 cadaveric heads, as well as a case with anterosuperior cerebellar cavernous angioma. EHOTA, which has the same advantages as EOTA, could prove to be an efficacious procedure for lesions in the anterosuperior cerebellum, upper fourth ventricle, and upper dorsal brain stem.

The value of a complex unit for the simultaneous use of a transverse surface and a longitudinal ridge when irrigating cotton

The article provides data on the development of a complex Palodelatel unit without damaging growing plants, the simultaneous rate of a transverse surface and a longitudinal ridge in saline, sloping uneven soils in the Bukhara region, also taking into account the slope and unevenness of the soil relief, in a scientifically based form it is stated about the uniform provision of irrigation water and reduction of manual labor, working time, duration and distance between irrigation days, saving spent irrigation water and elimination of salt spots and reducing the cost of irrigation water by 25%, irrigation duration by 1.5-2 days, crop addition by 5-4.2 c / ha.

Comparative Performance Analysis of Enhancement Methods Applied to Arabic Manuscripts

The ancient Arabic manuscripts are considered to be more complex regarding enhancement compared to others written in other languages. Complexity comes from character degradation, stains, low-quality images, curves of the text, character overlapping, etc. To facilitate the restoration, a set of well-known binarization techniques designed for historical document images is presented in this paper. Existing binarization techniques focus on either finding an appropriate global threshold for the whole image or adapting a local threshold for each area to achieve better enhancement quality. This improvement aims to remove noises, strains, uneven illumination, etc. The goal of our work is to assess these methods when applied to Arabic manuscripts in terms of readability, elimination of original spots and production of unwanted noise. Results show that no techniques work well for all types of manuscripts, but some techniques work better than others for particular types. Experimental results also indicate that Nick and Wolf techniques performed the best in terms of readability in most of the processed manuscripts.

Integral imaging based light field display with holographic diffusor: principles, potentials and restrictions.

Under the framework of light field, the diffusing angle and spatial location of holographic diffusor is investigated for the integral imaging based light field display. These two parameters are considered in terms of continuous light field reconstruction of the object point and blind visual spots elimination for the viewer. The concept of joint view reconstruction as well the essence of this view interpolation is analyzed theoretically, and a new phenomenon caused by the additional holographic plane called double window violation is also deduced. To the best of our knowledge, this is the first report on the quantitative analysis of the two key parameters of the holographic diffusor, which is deduced theoretically and verified experimentally.

Lemna gibba and Eichhornia crassipes extracts: Clean alternatives for deacidification, antioxidation and fungicidal treatment of historical paper

In this research Lemna gibba (L) and Eichhornia crassipes (E) ethanolic extracts were added to pure cellulose substrate to produce impregnated interleaving papers (LIP) and (EIP). These products are proposed to cure historical paper undergoing acidification, oxidation and fungal infection. The extracts were analysed using Gas Chromatography/Mass Spectrometer (GC/MS) and polyphenolic compounds were assessed. The products were tested on model decayed paper showing identical characteristics of historical paper, on which pH values were measured, transition metals concentrations were evaluated using Inductively Coupled Plasma- Optical Emission Spectrometry (ICP-OES) and samples were investigated using Scanning Electron Microscope combined with Energy Dispersive Spectroscopy (SEM-EDX) respectively. Radical scavenging and antioxidation activities of the extracts were also assessed using 1,1-diphenyl-2-picryl-hydrazyl free radical DPPH·. Results demonstrated a significant increase (P < 0.01) in the DPPH· free radical scavenging with increasing concentration in the following order vitamin C > BHT ≈ (L) extract > (E) extract. Results showed also that both (LIP) and (EIP) products effectively neutralized the acidity of decayed paper after 7 day treatment and evidently chelated transition metals. Zn2+ and Fe2+ were better chelated by (LIP) treatment in the order; Zn2+ > Fe2+ > Pb2+ > Cu2+, while Pb2+ and Cu2+ were greater removed by (EIP) treatment in the order Pb2+ > Cu2+ > Zn2+ > Fe2+. Up to 90% radical scavenging was achieved at 320.00 μg/mL concentration of (L) extract and 667.296 μg/mL concentration of (E) extracts. Aspergillus niger, Penicillium roqueforti and Eurotium chevalieri growth are inhibited at 1000 μg/mL concentration of LIP with considerable fungal spots elimination. Our findings established LIP and EIP products as novel natural origin alternative for effective synergic deacidification, antioxidation, antiradical, metal chelation and fungicidal treatment of historical paper.

Strategic Compilation of Rural Tourism Development Using SWOT- ANP Integrated Model (Case Study: Savar Village in Bonab County)

Strategic Compilation of Rural Tourism Development Using SWOT- ANP Integrated Model (Case Study: Savar Village in Bonab County)

Prioritized efficiency optimization for intensity modulated proton therapy

A high dosimetric quality and short treatment time are major goals in radiotherapy planning. Intensity modulated proton therapy (IMPT) plans obtain dose distributions of great conformity but often result in long delivery times which are typically not incorporated into the optimization process. We present an algorithm to optimize delivery efficiency of IMPT plans while maintaining plan quality, and study the potential trade-offs of these interdependent objectives. The algorithm is based on prioritized optimization, a stepwise approach to implemented objectives. First the quality of the plan is optimized. The second step of the prioritized efficiency optimization (PrEfOpt) routine offers four alternatives for reducing delivery time: minimization of the total spot weight sum (A), maximization of the lowest spot intensity of each energy layer (B), elimination of low-weighted spots (C) or energy layers (D). The trade-off between dosimetric quality (step I) and treatment time (step II) is controlled during the optimization by option-dependent parameters. PrEfOpt was applied to a clinical patient case, and plans for different trade-offs were calculated. Delivery times were simulated for two virtual facilities with constant and variable proton current, i.e. independent and dependent on the optimized spot weight distributions. Delivery times decreased without major degradation of plan quality; absolute time reductions varied with the applied method and facility type. Minimizing the total spot weight sum (A) reduced times by 28% for a similar plan quality at a constant current (changes of minimum dose in the target <1%). For a variable proton current, eliminating low-weighted spots (C) led to remarkably faster delivery (16%). The implementation of an efficiency-optimization step into the optimization process can yield reduced delivery times with similar plan qualities. A potential clinical application of PrEfOpt is the generation of multiple plans with different trade-offs for a multicriteria optimization setting. Then, the planner can select the preferred compromise between treatment time and quality for each individual patient.

Towards the Elimination of White Spots in Mobile WiMAX Grids through Time Efficient Cognitive Vertical Handoff Algorithm

During the past two decades particularly, there has been incredible growth in the telecommunication industry which evolved the demand for real time applications. Mobile grids and internet service providers are offering competitive real time services to customers in order to fulfil their daily demands. Nowadays, WiMAX has become a key player in telecommunication industry for providing cost effective communication solutions to customers residing in developed and underdeveloped regions. Moreover, a significant role of WiMAX technology is to fill the gap between the first-world and third-world countries. WiMAX technology offers affordable low cost wireless multimedia services to its customers by using point to multipoint propagation methods. Over the past few years, the problem of white spots in WiMAX grids has been reported in the literature extensively. Consequently, this issue has got a lot of attention from researchers. In order to disentangle the phenomenon of white spots, a novel algorithm based on time efficient cognitive vertical handoff scheme has been presented in this paper. The proposed algorithm is based upon principles of cognitive heterogeneous wireless grids. The simulation results have shown that the proposed algorithm is a promising candidate to overcome the problem of white spots in mobile WiMAX grids.

SU‐F‐BRD‐10: Improving Plan Delivery Efficiency of Intensity Modulated Proton Plans with Prioritized Optimization

Purpose:To integrate treatment delivery time into plan optimization in spot scanning intensity modulated proton therapy. Utilizing a dedicated research treatment planning system we present an optimization approach to explore the trade‐off between the correlated parameters treatment time and plan quality on an astrocytoma patient case.Methods:The planning system is based on prioritized optimization, a stepwise approach of implementing clinical goals. After each optimization step, dosimetric achievements are turned into hard constraints to maintain the achieved plan quality. Prior achievements can be violated by a so‐called slip‐factor which allows to study possible trade‐offs of conflicting goals. Plan quality is obtained in the first two steps, while the third step optimizes delivery efficiency by working on the spot weight distribution via four alternativeMethods:elimination of low weighted spots (1), elimination of spots hardly contributing to PTV dose, followed by reoptimization of the resulting smaller optimization problem (2), reduction of spot weights variance within each energy layer (3), and reduction of the overall spot weight sum (4). Treatment times were calculated assuming either constant or variable beam current depending on the lowest spot weight.Results:Delivery efficiency can be improved remarkably without influencing the plan quality. Absolute time savings depend on the utilized method and facility properties. By varying slip‐factor and spot reduction limits, a border of worsening quality is detectable for all methods.Deleting low weighted spots by 10% results in a noticeable decrease in minimum target dose. Further reduction results in more heterogeneous dose distributions and insufficient coverage. Option 2 showed constant plan quality for spot reductions of more than 10%.Conclusion:Including treatment time optimization as a final step into prioritized optimization allows for more efficient treatment plans by redistributing the spot patterns without compromising plan quality, which has to remain the main intent of radiotherapy treatment.The authors report grants from German Research Foundation (DFG) during the conduct of the study.

Influence of Selected Parameters of Continuous Casting in the Electromagnetic Field on the Distribution of Graphite and Properties of Grey Cast Iron

Abstract In paper problem concerning modification of grey cast iron EN-GJL-200 Grade, which is realized mainly by intensification of liquid metal movement in horizontal continuous casting mould containing electromagnetic stirrer is presented. The range of studies contains influence of electromagnetic field on morphology of graphite and usable properties i.e. tensile strength, hardness and machinability. Moreover the influence of velocity of ingot pulling on microstructure was analyzed. The results of studies and their analysis show possibility of improvement in quality of grey cast iron continuous ingot firstly in result of elimination of hard spots in structure by properly selection of velocity of ingot pulling and second in result of unification of size, shape and distribution of flake graphite by application of electromagnetic field.

Study on blind band elimination in jitter estimation

We propose a blind spot elimination method based on an improved layout of CCD in spacecraft jitter estimation. At least three CCDs are required and designed with two pairs of overlapping area and one non-overlap­ping pair. The two number of lines in space of overlapping pairs are made coprime to minimize the number of common blind spots. The third non-overlapping pair is arranged with the space less than the quotient of the least line frequency and bandwidth. It is used to eliminate the aliasing blind frequencies of the first two overlapping pairs. Experimental results prove the effectiveness of the blind band elimination.

THE STUDY ON HEIGHT INFORMATION EXTRACTION OF CULTURAL FEATURES IN REMOTE SENSING IMAGES BASED ON SHADOW AREAS

Abstract. Cultural feature is important element in geospatial information library and the height information is important information of cultural features. The existences of the height information and its precision have direct influence over topographic map, especially the quality of large-scale and medium-scale topographic map, and the level of surveying and mapping support. There are a lot of methods about height information extraction, in which the main methods are ground survey (field direct measurement) spatial sensor and photogrammetric ways. However, automatic extraction is very tough. This paper has had an emphasis on segmentation algorithm on shadow areas under multiple constraints and realized automatic extraction of height information by using shadow. Binarization image can be obtained using gray threshold estimated under the multiple constraints. On the interesting area, spot elimination and region splitting are made. After region labeling and non-shadowed regions elimination, shadow area of cultural features can be found. Then height of the cultural features can be calculated using shadow length, sun altitude angle, azimuth angle, and sensor altitude angle, azimuth angle. A great many of experiments have shown that mean square error of the height information of cultural features extraction is close to 2 meter and automatic extraction rate is close to 70%.

Focus Control in HIFU Therapy Assisted by Time-Reversal Simulation with an Iterative Procedure for Hot Spot Elimination

Both focus control and hot spot elimination applied to the High Intensity Focused Ultrasound (HIFU) treatment are addressed using three-dimensional numerical simulations, which can faithfully capture the pressure field in the HIFU system involving strong heterogeneity in material properties. The hot spot corresponds to the superficial secondary pressure peak, which originates in the reflection and refraction of the ultrasonic waves. As an extension of the Time Reversal theory (Fink, 1992, IEEE Trans. Ultrason. Ferroelectr. Freq. Control, 39, 555), which is based on the reversibility of the linear wave equation, a heuristic, iterative and self-adaptive process is proposed to make the HIFU system mounting array piezotransducers dynamically controllable. The amplitude and phase of the driving pressure on each transducer are determined from the temporal change in the monitored pressure of diverging acoustic waves emitted from virtual acoustic sources at the hot spot as well as the target point. The primary peak is found to be strengthened through the process, while the secondary peaks are to be obliterated. The present method is applied to a transskull HIFU simulation using human body voxel data, and its effectiveness is discussed.

Towards Developing an Indirect Video Visibility System for Large Trucks

Large trucks were involved in approximately 14,800 crashes between April 2001 and December 2003 as a result of making lane changes and merges (Starnes, 2006). The elimination of blind spots may help drivers avoid such conflicts by improving their spatial awareness of surrounding vehicles. This study investigated the ability of two candidate Camera/Video Imaging Systems (C/VISs) to provide information on longitudinal clearance to an adjacent vehicle. Sixteen commercial vehicle drivers performed merge maneuvers in front of an adjacent confederate vehicle while driving a tractor-trailer on the Virginia Smart Road. Both C/VIS enhancements were found to significantly improve gap judgment and merge performance. Performance differences between the two C/VIS concepts are examined.