Open Filter Research Articles

Controlling Seepage Flow Beneath Hydraulic Structures: Effects of Floor Openings and Sheet Pile Wall Cracks

Using one opening (filter) within the floors of hydraulic structures is a known technique to relieve the seepage effects on their floors. In this study, a new method to control seepage flow by using two identical filters instead of one was tackled numerically. A comparative analysis of using one versus two filters was conducted for different thicknesses of the permeable stratum, apron size (b), filter length, and sheet pile wall depths. Results indicate that two filters are considerably more effective than using one where the overall uplift force, the maximum potential head, and the hydraulic exit gradient downstream of the floor are reduced to 42–56%, 42–51%, and 66–76%, respectively, compared to one filter, while slightly increasing seepage flow by 1–7%. Many reasons can lead to horizontal openings (cracks) appearing along the sheet pile walls beneath hydraulic structures. The current study tackled their effects on seepage flow for the first time and examined their impact on the floor. A crack in the upstream sheet pile wall can increase total uplift forces by up to 40%, while a crack in the downstream sheet pile wall can increase the hydraulic exit gradient by up to 230%

Cardboard packaging minimization: Autonomous box selection by RGB-depth vision system and complementary deep learning classification

Amidst the dramatic expansion of online shopping, wasted cardboard packaging has become a significant challenge in modern-day society. In this paper, we propose an innovative approach to address the issue of box packaging waste by efficiently selecting an optimal cardboard box for a set of items. Employing depth vision and deep learning classification techniques, the proposed system analyzes depth images to compute an optimal cuboid for unpackaged items while accounting for fragility characteristics. The system, facilitated by two Intel RealSense RGB-D cameras, first captures the overhead and sideview images to determine the dimensions of an unknown object. Then, the developed vision system utilizes averaging and morphological opening filters to denoise the acquired images, calculates the difference between the background image and object image, and employs thresholding by Otsu’s algorithm to find the minimum cuboid of the irregular object. After, a two-step deep learning model is used to determine the general category and characteristics of an object, considering factors, such as fragility, that may necessitate wrapping or separate packaging. Finally, a modified largest area first fit algorithm uses the outputted dimensions for irregular-shaped objects and packaged objects to determine the optimal fitting box from the standard Amazon box catalog. The computer simulation shows that the proposed method can be implemented in a cardboard packaging warehouse for optimal box selection, effectively minimizing cardboard waste.

Open Filters and Congruence Relations on Self-Distributive Weak Heyting Algebras

Open Filters and Congruence Relations on Self-Distributive Weak Heyting Algebras

Microplastics, physical-chemical and biological principles of this environmental liability

The advent of plastic to the social situation has suppressed a series of demands from both the industry and the population, due to cost, durability and disposal. Because they can be rigid, malleable, opaque, translucent, easy or difficult to melt by the action of fire, some make them capable of serving as raw material for various products on the market, including those widely used in the food industry. In view of the above, the present study aims at a bibliographical review on the topic of microplastics, where the search will be to verify the primary and secondary steps necessary for the formation of the compound, its direct and indirect influence on food production, the physical-chemical processes through which compounds are obtained and the presence or absence of regulation regarding this environmental liability. The present study aims to analyze as a basis the search for knowledge of the primary and secondary formation of microplastics. Subsequently, together with its main objective, this study aims to search for the physico-chemical and thermodynamic phenomena involved in the process of formation and obtaining of microplastics, the polluting potential and, like all waste, its implications for human health. A study horizon was established covering the years 2015 to 2023, where 3,750 articles were found and after applying open access filters, duplication of publication, words present only in the abstract and not in the text, 49 articles remained that are the object of this study. The direct implications of microplastic pollution are already a relevant reason for discussion and subsequent regulation by managers, researchers, international organizations and society in general. Public health problems that can transform into microplastics, containment and adsorption mechanisms of these compounds in living organisms, are points to be pursued by academia as a whole. Contamination by these compounds was found in bottled mineral water, human milk, processed foods, seafood, showing the extent of contamination of this material.

An efficient algorithm for areal morphological filter

This article discusses morphological filtering for assessing a areal parameters of a texture of engineering products. A data organization structure has been proposed that makes it possible to increase the efficiency of an iterative algorithm for enumerating a surface coordinates. Morphological filters complement the standard Gaussian filter to evaluate the functional properties of a surface. The widespread use of the areal morphological filtering in metrological practice is currently hampered by the lack of an effective algorithm. An algorithm based on a matrix representation of morphological operations on the surface coordinates is presented. For this purpose, different indexing of points on a primary surface and a structuring element has been introduced. A sphere or flat segment is used as the structuring element. The high performance of the developed algorithm is ensured due to the fact that all calculations are carried out by enumerating the surface coordinates in one pass, without nested loops, as in some other algorithms. Algorithms for morphological operations of dilation and erosion are presented, on the basis of which a closing and opening filters are constructed. Simulations carried out for various data sets and comparison with known morphological filtering algorithms confirmed the high efficiency of the designed algorithm. The results obtained can be used to analyze the functional properties of product surfaces.

Molecular details of ruthenium red pore block in TRPV channels.

Transient receptor potential vanilloid (TRPV) channels play a critical role in calcium homeostasis, pain sensation, immunological response, and cancer progression. TRPV channels are blocked by ruthenium red (RR), a universal pore blocker for a wide array of cation channels. Here we use cryo-electron microscopy to reveal the molecular details of RR block in TRPV2 and TRPV5, members of the two TRPV subfamilies. In TRPV2 activated by 2-aminoethoxydiphenyl borate, RR is tightly coordinated in the open selectivity filter, blocking ion flow and preventing channel inactivation. In TRPV5 activated by phosphatidylinositol 4,5-bisphosphate, RR blocks the selectivity filter and closes the lower gate through an interaction with polar residues in the pore vestibule. Together, our results provide a detailed understanding of TRPV subfamily pore block, the dynamic nature of the selectivity filter and allosteric communication between the selectivity filter and lower gate.

Energy, exergy, sustainability, thermoeconomic, exergoeconomic, environmental and environmental-economic effects of novel boron-containing open cell geopolymer filter of a diesel engine on exhaust emissions

In this study, the energy, exergy, sustainability, thermoeconomic, exergoeconomic, environmental and environmental-economic based analyses are applied to the experimentally developed (3 % boric acid based) boron-doped geopolymer filter used for the diesel engine to assess it in a large engineering point of view. In this context, novel boron-doped filter exhaust after treatment system (BDF EAS) is compared with catalytic exhaust after treatment system (catalytic EAS) and unfiltered option (filterless) with engine loads of 50 Nm, 75 Nm and 100 Nm, while engine speeds are 1500 rpm, 1700 rpm, and 1900 rpm. The utilization of the newly developed BDF EAS has a significant effect on the exhaust emission particles. It effectively filters the particles compared to the original catalytic EAS of the engine. On the other hand, the developed BDF EAS has effective oxidation process for the emissions. So, the newly developed boron-doped filter can be used as a single device that has both of the Diesel Oxidation Catalyst (DOC) and Diesel Particulate Filter (DPF) specifications together. Hence, the new product of BDF EAS is environmentally benign system for the diesel engines and boron-doped geopolymer material can be used as an innovative material in the automotive industry's exhaust emission control system.

Two topologies on the set of minimal prime elements of a continuous frame

In this paper, we discuss the properties of the hull-kernel topology and the inverse topology on the set [Formula: see text] of minimal prime elements of a continuous frame [Formula: see text]. We prove that the set [Formula: see text] endowed with the hull-kernel topology and the inverse topology, respectively, is a [Formula: see text]-space. Moreover, we obtain that there is a bijective correspondence between the set [Formula: see text] of all maximal Scott open filters of [Formula: see text] and the set [Formula: see text] when [Formula: see text] is a stably continuous frame. By considering the bijective correspondence between the sets [Formula: see text] and [Formula: see text], we propose some sufficient conditions for the topological spaces [Formula: see text] endowed with the hull-kernel topology and the inverse topology, respectively, to be sober, Hausdorff, compact, extremely disconnected and zero-dimensional spaces, respectively, when [Formula: see text] is a stably continuous frame.

Vehicle Target Recognition Method Based on Visible and Infrared Image Fusion Using Bayesian Inference

The accuracy of single-mode optical imaging systems for vehicle target recognition is limited by external ambient illumination or imaging equipment resolution. In this paper, a vehicle target recognition method based on visible and infrared image fusion using Bayesian inference is proposed. Based on the significance area detection combined with Spectral Residual (SR) and EdgeBox algorithms, the target area is marked on the visible light image, and the maximum between-class variance method and GrabCut algorithm are used to segment vehicle targets in marked images. The open operation filter is employed to extract the vehicle target features in the infrared image, and the fusion result of the visible light image and the infrared image is obtained by introducing the Intersection Over Union (IOU), and as the parameter of Bayesian inference, the class and attribute of the parameter are defined and substituted into the established naive Bayesian classification model, and the probability of the class is calculated to determine whether the vehicle target is recognized. Experiments under different test conditions were carried out, and the experimental results were as follows: the accuracy of image target recognition reached 77% when the vehicle target was not occluded; when the vehicle target was partially occluded, the accuracy of image target recognition reached 74%; the results verified that the proposed method can recognize vehicle targets in different scenarios.

Removal of inferior vena cava filter by open surgery after failure of endovenous retrieval.

The permanent placement of inferior vena cava (IVC) filters may lead to numerous complications and their removal is recommended once the risk of pulmonary embolism is reduced. Removal of IVC filters by endovenous means is preferred. But failure of endovenous removal happens when recycling hooks penetrate the vein wall and filters are left in place for too long time. In these scenarios, open surgery may be effective for removal of IVC filters. We aimed to describe the surgical approach, outcomes, and 6-month follow-up of the removal of IVC filter by open surgery, after the failure of removal via the endovenous method. A total of 1,285 patients with retrievable IVC filters were admitted from July 2019 to June 2021, including 1,176 (91.5%) endovenous filter removals, and 24 (1.9%) open surgical IVC filter removals after the failure by endovenous method, of whom 21 (1.6%) were followed-up and eligible for analysis of the study. Patient characteristics, filter type, filter removal rate, IVC patency rate, and complications were retrospectively analyzed. Twenty-one patients were left with IVC filters for 26 (10, 37) months, of which 17 (81.0%) patients had non-conical filters and 4 (19.0%) had conical filters; all 21 filters were successfully removed, with a 100% removal rate, no deaths, no serious complications, and no symptomatic pulmonary embolism. At the 3rd month follow-up after surgery and 3rd month follow-up after discontinuation of anticoagulation therapy, only 1 case (4.8%) had IVC occlusion, but without any occurrence of new lower limb deep venous thrombosis and silent pulmonary embolism. Open surgery can be used for the removal of IVC filters after failure of removal by endovenous method or when accompanied by complications without symptoms of pulmonary embolism. Open surgical approach can be used as an adjunctive clinical intervention for the removal of such filters.

Open planar acoustic notch filter using a film-integrated Helmholtz resonator array

Acoustic filters are used to transmit or attenuate noise in a specific frequency band. However, previous acoustic filters consisting of rigid structures generally required a large housing of a size equivalent to the wavelength, limiting their downsizing. This study presents an open planar acoustic notch filter using a film-integrated Helmholtz resonator (HR) array. A film divides the HR chamber and resonates with the HR. The film-integrated HR array filter achieved smaller housing dimensions than a no-film HR array filter with the same notch frequency. The transmittance of the film-integrated HR array was theoretically calculated using the transfer matrix method. The calculated spectra were very similar to the simulation results. The notch frequency of the film-integrated HR array filter was 4.04, 0.74 kHz lower than a no-film HR array filter. The design and analysis of the acoustic filter presented should motivate further development of advanced acoustic filters.

Modulation of TRPV2 by endogenous and exogenous ligands: A computational study.

Transient receptor potential vanilloid (TRPV) channels play various important roles in human physiology. As membrane proteins, these channels are modulated by their endogenous lipid environment as the recent wealth of structural studies has revealed functional and structural lipid binding sites. Additionally, it has been shown that exogenous ligands can exchange with some of these lipids to alter channel gating. Here, we used molecular dynamics simulations to examine how one member of the TRPV family, TRPV2, interacts with endogenous lipids and the pharmacological modulator cannabidiol (CBD). By computationally reconstituting TRPV2 into a typical plasma membrane environment, which includes phospholipids, cholesterol, and phosphatidylinositol (PIP) in the inner leaflet, we showed that most of the interacting surface lipids are phospholipids without strong specificity for headgroup types. Intriguingly, we observed that the C-terminal membrane proximal region of the channel binds preferentially to PIP lipids. We also modelled two structural lipids in the simulation: one in the vanilloid pocket and the other in the voltage sensor-like domain (VSLD) pocket. The simulation shows that the VSLD lipid dampens the fluctuation of the VSLD residues, while the vanilloid lipid exhibits heterogeneity both in its binding pose and in its influence on protein dynamics. Addition of CBD to our simulation system led to an open selectivity filter and a structural rearrangement that includesa clockwise rotation of the ankyrin repeat domains, TRP helix, and VSLD. Together, these results reveal the interplay between endogenous lipids and an exogenous ligand and their effect on TRPV2 stability and channel gating.

Extraction and characterization of waxy and normal barley β-glucans and their effects on waxy and normal barley starch pasting and degradation properties and mash filtration rate

Interactions between β-glucan and starch influence the health benefits of barley-based foods and barley brewing performance. Here, we characterized β-glucans from waxy and normal barley varieties and compared the effects of different β-glucans on the pasting and degradation of waxy and normal barley starches as well as the filterability of mashes from unmalted waxy and normal barley. Waxy barley Zangqing18 β-glucan displayed more compact micrographic features, higher molecular weight, larger particle size, higher thermal decomposition temperature and lower rheological viscosity than normal barley Zangqing2000 β-glucan. β-Glucan not only significantly decreased the pasting viscosities of waxy and normal starches but also lowered the pasting temperatures and peak times of normal starch, likely by inhibiting granule swelling and disrupting the integrity of the continuous phase. β-Glucan also decreased in vitro digestion extent of starch and increased the resistant starch. The unmalted waxy barley had a mash filtration rate much faster than normal barley because starch and β-glucan in waxy barley were rapidly and completely digested and formed more open filter passages. The effects of β-glucan on starch properties varied with the types and contents of β-glucans, whilst the types of starches showed more significant effects. Chemical compounds studiedβ-Glucan (Pubchem CID: 439262); Amylopectin (Pubchem CID: 439207); Starch (Pubchem CID: 156595876).

Exposure to bacterial and fungal bioaerosols in facilities processing biodegradable waste.

The aim of the study was to determine the exposure of workers within biodegradable waste processing facilities to bacteria and fungi to identify any exposures of potential concern to health. Occupational measurements were performed in six composting and three bioenergy (bioethanol or methane/biogas) producing facilities. Bioaerosols were measured from breathing zones with Button aerosol or open face cassette filter samplers, and swab specimens were taken from the nasal mucous membranes of the workers. Aspergillus fumigatus, Bacillus cereus group, Campylobacter spp., Salmonella spp., Streptomyces spp., and Yersinia spp. were determined by real-time polymerase chain reaction (qPCR). A. fumigatus, and mesophilic and thermophilic actinobacteria were also cultivated from filters. Bacterial airborne endotoxins collected by IOM samplers were analyzed using a Limulus assay. Bioaerosol levels were high, especially in composting compared to bioenergy producing facilities. Endotoxin concentrations in composting often exceeded the occupational exposure value of 90 EU/m3, which may be harmful to the health. In addition to endotoxins, the concentrations of A. fumigatus (up to 2.4 × 105 copies/m3) and actinobacteria/Streptomyces spp. (up to 1.6 × 106 copies/m3) in the air of composting facilities were often high. Microbial and endotoxin concentrations were typically highest in waste reception and pre-treatment, equal or decreased during processing and handling of treated waste, and lowest in wheel loader cabins and control rooms/outdoors. Still, the parameters measured in wheel loader cabins were often higher than in the control sites, which suggests that the use of preventive measures could be improved. B. cereus group, Salmonella spp., and Yersinia spp. were rarely detected in bioaerosols or nasal swabs. Although Campylobacter spp. DNA was rarely detected in air, as a new finding, Campylobacter ureolyticus DNA was frequently detected in the nasal mucous membranes of workers, based on partial 16S rDNA sequencing. Moreover, especially A. fumigatus and C. ureolyticus spp. DNA concentrations in swabs after the work shift were significantly higher than before the shift, which indicates their inhalation or growth during the work shift. Microbial qPCR analysis of bioaerosols and swab samples of nasal mucosa allowed measuring exposure in various work operations and during the work shift, identifying problems for health risk assessment to improve working conditions, and evaluating the effectiveness of preventive measures and personal protection of workers.

On subcompactness and countable subcompactness of metrizable spaces in ZF

We show in ZF that: (i) Every subcompact metrizable space is completely metrizable, and every completely metrizable space is countably subcompact. (ii) A metrizable space $\mathbf{X}=(X,T)$ is countably compact if and only if it is countably subcompact relative to $T$. (iii) For every metrizable space $\mathbf{X}=(X,T)$, the following are equivalent: \noindent(a) $\mathbf{X}$ is compact; \noindent(b) for every open filter $\mathcal{F}$ of $\mathbf{X}$, $\bigcap \{\overline{F}\colon F\in \mathcal{F}\}\neq \emptyset $; \noindent(c) $\mathbf{X}$ is subcompact relative to $T$. We also show: (iv) The negation of each of the statements, (a) every countably subcompact metrizable space is completely metrizable, (b) every countably subcompact metrizable space is subcompact, (c) every completely metrizable space is subcompact, is relatively consistent with ZF. (v) AC if and only if for every family $\{\mathbf{X}_{i}\colon i\in I\}$ of metrizable subcompact spaces, for every family $\{\mathcal{B}_{i}\colon i\in I\}$ such that for every $i\in I$, $\mathcal{B}_{i}$ is a subcompact base for $\mathbf{X}_{i}$, the Tychonoff product $\mathbf{X}=\prod_{i\in I} \mathbf{X}_{i}$ is subcompact with respect to the standard base $\mathcal{B}$ of $\mathbf{X}$ generated by the family $\{\mathcal{B}_{i}\colon i\in I\}$.

Social Workers as Information Navigators: Insights into the Use of the Web for Serving Clients.

Social workers' critical role as service navigators on behalf of their clients is expanding in the online space at a faster pace than ever before. This study examined the process and outcome of online information navigation through the lens of service providers and service users based on observational and interactive surveys. T tests and correlation results showed that human services providers demonstrated a higher capacity to visit more websites and yield more accurate search outcomes in a similar duration of time compared with general service users. Results suggest that digital literacy for navigating information online can be improved through educational opportunities. At the same time, both groups shared some common feedback on desired features for future service navigation online, including but not limited to an open search bar, search filters, instruction videos, live chat, and discussion forums for seeking mutual help and networking. The findings bear implications for formulating the roles, responsibilities, and desired competencies of social workers for online service navigation in the digital and postpandemic future.

The role of bypass filters in deceased donor kidney allocation in the United States

Kidney transplant centers set organ offer filters enabling all candidates at their center to be bypassed during allocation of deceased donor kidneys from the UNOS Organ Center. These filters aim to increase allocation efficiency by preemptively screening out offers unlikely to be accepted. National data were used to compare filter settings of 175 centers in 2007 and in 2019. We examined characteristics of centers whose settings became increasingly restrictive over time, and associations between filter settings and organ offer acceptance. Overall, centers became more open to receiving offers over time, from a median 62% of filters open to receiving national offers in 2007 to 73% in 2019. Intravenous drug use filter settings changed most, from 63 to 153 willing centers. Centers with more open filter settings had higher transplant volume and offer acceptance ratios across all risk categories despite preemptively screening out fewer offers compared to centers with less open settings, but similar transplant rates. There was significant geographic heterogeneity in the distribution of centers with more open filter settings. Current center bypass filters may impact patients' access to transplantation without achieving their full potential for improving allocation efficiency.

Minimal Soft Topologies

A collection of all soft topologies over a fixed universe forms a complete lattice. One might ask: what will be the structure of minimal or maximal topologies in this lattice concerning specific topological properties? We know that the soft discrete topology is maximal soft [Formula: see text]-spaces, for [Formula: see text], in terms of the given soft point theory. As a result, we find it interesting to study the construction of minimal soft [Formula: see text] topologies. We show that the minimal soft [Formula: see text] is a nested soft topology whose base is the complements of all soft point closures. The minimal soft [Formula: see text] is the cofinite soft topology. The minimal soft [Formula: see text] (respectively, [Formula: see text]) is a soft topology in which each soft open (respectively, soft regular) filter base has only one adherent soft point and is convergent. Finally, the minimal soft [Formula: see text] topologies are subclasses of soft compact topologies.

Hofmann-Mislove type definitions of non-Hausdorff spaces

AbstractOne of the most important results in domain theory is the Hofmann-Mislove Theorem, which reveals a very distinct characterization for the sober spaces via open filters. In this paper, we extend this result to the d-spaces and well-filtered spaces. We do this by introducing the notions of Hofmann-Mislove-system (HM-system for short) and $\Psi$ -well-filtered space, which provide a new unified approach to sober spaces, well-filtered spaces, and d-spaces. In addition, a characterization for $\Psi$ -well-filtered spaces is provided via $\Psi$ -sets. We also discuss the relationship between $\Psi$ -well-filtered spaces and H-sober spaces considered by Xu. We show that the category of complete $\Psi$ -well-filtered spaces is a full reflective subcategory of the category of $T_0$ spaces with continuous mappings. For each HM-system $\Psi$ that has a designated property, we show that a $T_0$ space X is $\Psi$ -well-filtered if and only if its Smyth power space $P_s(X)$ is $\Psi$ -well-filtered.

Substantiation of technological solutions for the protection of water resources in the development of coal deposits

In the case of mechanical treatment of mine water in settling tanks according to the existing technology the concentration of suspended solids during the discharge of clarified effluents into water bodies does not correspond to the maximum permissible content of mechanical impurities set for surface water bodies. The technology of mine water cleaning has been improved due to the introduction of a horizontal settling tank of modernized construction and installation of purification of fast open granular filters with downward liquid flow at the final stage. The expected technological parameters of the proposed horizontal settling tank for the conditions of water disposal of the operating coal mining enterprise are determined. The dependences between the depth of sedimentation of particles of the suspension of a certain hydraulic size in the proposed horizontal settling tank, its length and clarifying efficiency of mine water pre-treated with a solution of aluminium sulphate are obtained. It is established that the overall efficiency of clarifying of mine waters pumped to the surface by a coal mining enterprise, after treatment by the proposed technology will be 94-95% of the initial concentration of suspended solids, which does not exceed the relevant quality of surface water.