Open Channel Research Articles

Work-life balance strategies and employees’ engagement in the food and beverage industry in rivers state

This study explores the nexus between work-life balance (WLB) strategies and employees’ engagement (EE) within the food and beverage (F&B) industry. Employing a quasi-experimental design, data was gathered from 165 employees across selected F&B organizations using a closed-ended Likert-type scale questionnaire. Data analysis via Pearson’s Product Moment correlation (PPMC) statistical technique revealed a positive and significant relationship between the dimensions of work-life balance (WLB) strategies and measures of employees’ engagement (EE) within the food and beverage (F&B) industry. Specifically, the results indicate a robust positive and significant correlation between Work interference with personal life (WIPL) and the measures of employees’ engagement: employees’ emotional engagement (EEE) and employees’ behavioral engagement (EBE), with values ranging from 0.894 to 0.881 respectively. Additionally, personal life interference with work (PLIW) demonstrates a notable positive correlation with the measures of employees’ engagement, attributing to 72.5% to 83.5% of emotional and behavioral engagement, respectively. Furthermore, work enhancement of personal life (WEPL) initiatives and personal life enhancement of work (PLEW) initiatives exhibited very strong positive associations with the measures of employees’ engagement, explaining up to 74% to 85% of emotional and behavioral engagement, respectively. These findings corroborate prior research, highlighting the significance of addressing Work-Life Balance issues to bolster employees’ engagement levels. Practically, the study underscores the importance for managers in the Food and Beverage to prioritize strategies that mitigate work-life interference, such as flexible scheduling and family-friendly policies, to foster higher EE levels. Tailored initiatives and training programs should be implemented to address specific WLB aspects identified within organizations, while fostering open communication channels to identify areas for improvement. By prioritizing WLB and supporting employee well-being, managers can cultivate a more engaged and productive workforce, ultimately contributing to organizational success. Other theoretical and practical implications for promoting WLB and fostering employees’ engagement in the Nigerian workplace are also discussed.

PYTHON-МОДЕЛЬ ПРОТОКОЛУ УЗГОДЖЕННЯ СЕКРЕТНОГО КЛЮЧА У ГРУПІ З ДОВІЛЬНОЇ КІЛЬКОСТІ УЧАСНИКІВ

The article is devoted to the problem of common secret key agreement in a group of an arbitrary number of participants. Data is exchanged between participants through open data channels. The problem of sharing a secret key over open data channels arose due to the need for a secure exchange of information between two or more parties that may be remote from each other and do not have a common confidential communication channel. Reliable methods of secret key exchange, such as transferring the key in person or using a secure channel, are not practical in remote or scalable scenarios. In the process of developing and modelling cryptographic systems, in which there is a need of cryptographic keys agreement in a group of two or more participants, it is very convenient to have a model that implements these algorithms. The agreement protocol is based on the Diffie-Hellman protocol on elliptic curves (ECDH). The paper contains theoretical justifications, a flow chart of the algorithm, and a Python implementation of the algorithm that performs the secret key agreement in a group of an arbitrary number of participants. To implement cryptographic operations on elliptic curves, the Python library Cryptography is used, in particular, the X25519 algorithms that use the elliptic curve Curve25519. The results of the work are shown on an example for a group of four participants, which demonstrate the correct operation of the model and the same secret key obtained as a result of agreement process. The paper also contains the link to a GitHub repository with the full program. The multi_participant_ecdh.py file contains a secret key agreement program for N participants written in Python. The file two_participant_ecdh.py demonstrates a typical two-participant Diffie-Hellman protocol. Both programs use the X25519 algorithm implemented in the Cryptography Python library. Thus, this work makes it possible to better understand the principles of secret key exchange algorithms between two and an arbitrary number of participants, to compare the results with other implementations, to apply the developed model for educational and demonstration purposes, and may be useful for a number of other scientific and engineering tasks.

An In-Depth Investigation of Micropillar Array Columns for the Separation of Finite-Sized Particles by Hydrodynamic Chromatography.

The exact moment approach (EMA) is adopted to predict, without any fitting parameters, the plate height curves for polystyrene microparticles of different sizes in micropillar array columns performed by hydrodynamic chromatography. The EMA allows us to decouple the contribution of horizontal and vertical dispersion terms and thus investigate the influence of pillar height and interpillar distance on separation performance. In the convection-controlled regime, we found that axial dispersion is mainly controlled by the vertical dispersion term, the latter being due to the flow-arresting top and bottom walls. This vertical contribution can be estimated from the axial dispersion in rectangular, open tubular channels formed between the pillars. Henceforth, plate height curves can be accurately predicted by simply adding the estimated vertical term to the horizontal dispersion term evaluated from 2D simulations. This finding allowed us to understand that, to improve separation performance, it is advisible to decrease the interpillar distance (expected result) and decrease the pillar height (counterintuitive result).

Flow resistance of emergent rigid vegetation in steady flow

Abstract Enhanced understanding of flow resistance in open channels with emergent vegetation is essential for flood management and river ecosystem restoration. The presence of vegetation can significantly alter bed resistance, leading to a challenge in accurately predicting flow discharge, water levels, sediment transport, and bed deformation. Previous studies on vegetated flows have focused on vegetation resistance, on which the impact of vegetation has been ignored or poorly estimated. This study proposes a new analytical model, built upon the momentum conservation law, to predict flow resistance to vegetated zones in a plain bed without bed forms, explicitly quantifying bed resistance and vegetation resistance in a corollary manner. The proposed model is benchmarked against five typical sets of laboratory experiments. It is demonstrated that the present model using a modified logarithmic velocity distribution performs best, whereas that assuming a uniform velocity profile considerably overestimates the vegetation resistance and neglects the effect of vegetation on bed resistance. The ratio of bed resistance to the total resistance is shown to range between 5% and 40%, and it decreases with increasing vegetation density and decreases with water depth. Therefore, bed resistance cannot be ignored when modelling shallow water flow with sparsely distributed vegetation. It is also revealed that vegetation arrangements significantly affect flow resistance, and therefore a model incorporating the effect of vegetation arrangement performs better. Overall, the present model facilitates a viable and promising tool for quantifying flow resistance in emergent vegetated channels.

Numerical evaluation of low-head inverted cross-flow turbine design method: A comprehensive study

This study aimed to address the challenges of micro-hydropower generation in low-head environments to expand the proportion of hydropower in renewable energy and achieve a carbon neutrality policy. To achieve these goals, various factors affecting the micro-hydro systems, including geographical constraints, construction costs, and grid connectivity, were reviewed and assessed. The results concluded that a novel type of cross-flow turbine with inverted structures, improved the economic feasibility, productivity, and installability of micro-hydropower plants by reducing head losses in open channels or small streams. The parametric studies consisted of four steps: first, designing the initial inverted cross-flow turbine based on the traditional design rules; for the second and third steps, a parametric study for comparing the runner diameter ratio and the number of blades is conducted; and in the last step optimized turbine was designed. The best efficiency point of the optimized inverted cross-flow turbine was 72.92 % at a runner rotational speed of 170 RPM with a 0.75 runner diameter ratio and 35 blades. The optimized turbine was improved by 7.8 % in power and 7.35 % in efficiency, higher than the initial turbine. From the hill chart comparison between the initial and optimized turbine, operation range expansion was confirmed. Overall, this research demonstrates the potential of the inverted cross-flow turbine under low-head conditions.

A Robust Pyrazolate Metal-Organic Framework for Efficient Catalysis of Dehydrogenative C-O Cross Coupling Reaction.

Construction of robust heterogeneous catalysts with atomic precision is a long-sought pursuit in the catalysis field due to its fundamental significance in taming chemical transformations. Herein, we present the synthesis of a single-crystalline pyrazolate metal-organic framework (MOF) named PCN-300, bearing a lamellar structure with two distinct Cu centers and one-dimensional (1D) open channels when stacked. PCN-300 exhibits exceptional stability in aqueous solutions across a broad pH range from 1 to 14. In contrast, its monomeric counterpart assembled through hydrogen bonding displays limited stability, emphasizing the role of Cu-pyrazolate coordination bonds in framework robustness. Remarkably, the synergy of the 1D open channels, excellent stability, and the active Cu-porphyrin sites endows PCN-300 with outstanding catalytic activity in the cross dehydrogenative coupling reaction to form the C-O bond without the "compulsory" ortho-position directing groups (yields up to 96%), outperforming homogeneous Cu-porphyrin catalysts. Moreover, PCN-300 exhibits superior recyclability and compatibility with various phenol substrates. Control experiments reveal the synergy between the Cu-porphyrin center and framework in PCN-300 and computations unveil the free radical pathway of the reaction. This study highlights the power of robust pyrazolate MOFs in directly activating C-H bonds and catalyzing challenging chemical transformations in an environmentally friendly manner.

Amidoximated‐Wood Derived Carbons as Advanced Self‐Standing Electrodes for Supercapacitor and Water Splitting

AbstractWood‐derived carbons demonstrate great potential as self‐standing electrodes in energy storage/conversion applications, including supercapacitors and water‐splitting devices. However, the key challenge remains the rational customization of surface functionalities for optimized performance. This study introduces an innovative approach to self‐standing wood‐derived carbons with tailored nitrogen and metal functionalities. In contrast to traditional impregnation techniques, which offer limited precision in surface modification, this approach entails the intentional attachment of amidoxime groups to the wood substrates. These groups serve as nitrogen sources, and create abundant surface anchoring sites for metal ions due to the chelation between the amidoxime groups and metals. The resulting carbons feature uniform and high dispersion of nitrogen and metal functionalities, along with a distinctive hierarchical porosity combining interconnected open channels with abundant mesopores. As a proof‐of‐concept, different metals are incorporated (i.e., Mn, Co, Ni) into the amidoximated‐wood precursors, and the resulting self‐standing carbons showcase excellent performance in both supercapacitors and water‐splitting applications. Leveraging the specific chelating ability of amidoxime groups toward metal ions, this strategy holds great potential as a generic approach to systematically tailoring the surface functionalities of carbon‐based materials for various electrochemical energy storage/conversion processes.

Novel paddy-like Bi-Sb-Cu alloy fabricated via pulse reverse potential electrodeposition enabling high-performance sodium-ion batteries

Sodium-ion batteries (SIBs) have gained remarkable interest as cost-effective and scalable energy storage devices. Nevertheless, their further application has been significantly hindered due to the limited selection of desirable anode materials that can provide both high capacity and excellent cycling stability. Herein, we developed a hierarchical paddy-like Bi42.3Sb35.2Cu22.5 alloy anode on Cu foil via template-free pulse reverse potential electrodeposition. The Bi42.3Sb35.2Cu22.5 anode obtains a considerable specific capacity of 529.5 mAh·g−1 after 120 cycles with a remarkable capacity retention of 95.5 %, signifying a capacity loss of only 0.0375 % per cycle. However, Bi44.9Sb55.1 anodes obtained by the pulse potential electrodeposition strategy reveal a conventional irregular cluster structure, delivering only 64.5 mAh·g−1 after 100 cycles and also demonstrating inferior rate performance compared to Bi42.3Sb35.2Cu22.5 anodes. The enhanced cycling performance of the paddy-like Bi42.3Sb35.2Cu22.5 anode is primarily attributed to the introduced Cu-doped network facilitating the rapid diffusion of Na+ and also ensuring the stability of the electrode structure. Moreover, the unique paddy-like structure of Bi42.3Sb35.2Cu22.5 mitigates volume expansion-related stress and facilitates efficient charge transport through open channels. This is further corroborated by conducting CV measurements, indicating a greater capacitive contribution in the case of the Bi42.3Sb35.2Cu22.5 electrode compared to the Bi44.9Sb55.1 electrode. Additionally, SEM images show a stabilized surface morphology for the Bi42.3Sb35.2Cu22.5 electrode after cycling, demonstrating improved electrochemical performance. This work offers new insights into the development of high-performance anode materials for SIBs.

Prediction of the flow resistance in non-prismatic compound channels

Prediction of the flow resistance in non-prismatic compound channels

Spectral Characteristics Analysis of Images Matrix Masking Results

The article describes the results of a computational experiment to assess the capabilities of extracting useful information if an image masked by quasi-orthogonal matrices sent over an open channel became available to a third party. Hadamard and Mersenne matrices of symmetric and cyclic structure are considered. The results confirm the data that images masked by small-sized matrix leaves edges of the original image on the masked image. However, with an increase in the size of the masking matrix, all considered in the article matrices reliably hides the original image during visual analysis. Masking by symmetric Mersenne-Walsh matrices and cyclic Mersenne matrices based on modified M-sequences provides better spectral secrecy of masked images in comparison with Hadamard matrices. Mersenne matrices of cyclic structure, with equal sizes of the image and the masking matrix, bring the phase spectrum of the masked image to a form close in spectrum to uniform noise, which makes their use more preferable based on the considerations that the human visual system is extremely sensitive to phase-frequency distortions of the visual information.

Deformation of vegetated channel bed under ice-covered flow conditions

A common feature of cold regions is the presence of ice cover on water surface. In the presence of vegetation in the channel bed which is normally leafless in winter, interaction between river ice and vegetated channel bed becomes very complex. In the present study, the impacts of ice cover and submerged leafless vegetation on channel bed deformation and flow resistance have been investigated based on 144 experiments conducted in a large-scale outdoor flume. The independent variables associated with the maximum scour depth around vegetation elements have been assessed and equations have been developed. Results indicate that the most important variable affecting the maximum scour depth around vegetation under ice-covered flow conditions is the ratio of the ice cover roughness to the bed roughness (ni/nb). However, under open channel flow conditions, the flow Froude number is the most important variable influencing the maximum scour depth. The methods based on the law of the wall provide reliable Manning's coefficient for both smooth and rough ice covers in the presence of submerged vegetation in the channel bed. As the vegetation density increases, the size of scour holes becomes smaller. With the increase in vegetation density, the median grain size of the armour layer in scour holes decreases correspondingly. When vegetation elements are placed in a staggered configuration, the median grain size of the armour layer in scour holes is less than that of squared configuration of vegetation elements. Regardless of the roughness of ice cover on water surface and the grain size of sediment in the bed, the maximum depth of scour holes always occurs at the upstream front face of each vegetation element. Under the rough ice-covered flow condition, the maximum depth of scour holes is more than that under the smooth ice-covered and open flow conditions.

Impact of downstream obstructions on ogee weir efficiency: a regression analysis

ABSTRACT This study delves into the impact of downstream obstruction angles on the discharge coefficient (Cd) over ogee weirs within open channel flows, a critical factor for accurate flow rate predictions in hydraulic engineering. Employing a series of detailed laboratory experiments the influence of various obstruction angles on Cd was scrutinized applying a suite of regression analysis to develop predictive models. The analysis was enriched by considering hydraulic parameters such as flow rate, water level, and weir geometry. Despite the established importance of Cd in hydraulic designs the nuanced effects of downstream obstructions have received limited attention highlighting a critical research gap. The findings highlight a strong correlation between obstruction angles and Cd, with developed regression models demonstrating notable predictive strength. Remarkably the models exhibited varying levels of accuracy, with the Random Forest regressor achieving an exceptionally low root mean square error (RMSE) of 0.005, indicating superior predictive performance. Conversely, traditional models like Decision tree and XG BOOST reflected higher RMSE values of 0.60, suggesting less predictive accuracy in this context. LASSO, Bayesian Ridge, and OMP regressors stood out with an RMSE of zero, denoting perfect predictions under the study's specific conditions.

Additive manufacturing of scalable jet impingement and radial taper enhancements for improved flow boiling performance

Additive manufacturing (AM) offers a unique route to improve flow boiling heat transfer by enabling the fabrication of complex fluidic devices. In this study, two types of advanced jet impingement designs were additively manufactured and tested in subcooled flow boiling with 20 °C of subcooling. The first design is an in-line extended nozzle jet impingement manifold with nozzles off angle to the flow direction that extend towards the heated surface in order to decrease pressure drop and reduce viscous dissipation. The influence of jet velocity was explored and the optimal 3 nozzle design achieved a critical heat flux (CHF) of 191 W/cm2 and heat transfer coefficient (HTC) of 42.1 kW/m2K at a pressure drop of 3.4 kPa. This represents a 78% increase in CHF and 64% increase in HTC compared to open flow conditions. Following this, a second more complex design was created combining jet impingement, tapered flow paths, radial flow, and intricate fluidic routing to further improve heat transfer. This complex design would be extremely difficult to manufacture without additive techniques and resulted in a CHF of 375 W/cm2 and HTC of 74.2 W/m2K at a pressure drop of 3.5 kPa at a flow rate of 300 mL/min. This represented a 250% and 189% increase in CHF and HTC respectively over open channel flow conditions at a low pressure drop. These designs are easily scalable, and represent a new class of “on surface” flow boiling jet impingement enhancement techniques enabled through the use of additive manufacturing of polymeric materials.

Characteristics of very-large-scale motions in natural rivers based on large eddy simulation

Exploring very-large-scale motions (VLSMs) in open channel flows (OCFs) is crucial for comprehensively understanding material transport and energy exchange. While previous studies focused on OCFs in ideal flumes with simple boundaries, this paper presents large eddy simulation (LES) results on the existence and scale characteristics of VLSMs in complex river morphologies with the Minjiang River in southwestern China as a case study. This research demonstrates that the OpenFOAM-based LES model is capable of accurately reconstructing the time-averaged flow field and providing instantaneous velocity data that capture VLSMs with sufficient resolution. Spectrum analysis of the streamwise fluctuating velocity shows that VLSMs are present in the straight segment of the river, with streamwise wavelengths approximately (16–22) times the water depth but are absent in the bend and confluence segments due to the suppression by secondary currents. This article validates the effectiveness of LES in examining the characteristics of VLSMs in natural rivers, thereby laying a good foundation for further studies on the impacts of such structures on sediment transport and pollutant dispersion.

WELL-BEING AMONG SENIOR HIGH SCHOOL LEARNERS: A LITERATURE REVIEW

This literature review synthesizes a wide range of scholarly articles and official documents to explore the multifaceted concept of well-being, particularly in the context of education and mental health. Drawing upon theoretical frameworks such as Maslow's hierarchy of needs, ecological systems theory, and positive psychology, the review provides a comprehensive examination of the various dimensions that contribute to individual well-being. Key themes include the importance of addressing physical, social, emotional, and spiritual aspects of well-being within educational settings, as well as the role of holistic wellness programs in promoting overall health and happiness. The review highlights the significance of subjective well-being as a subjective evaluation of an individual's quality of life, emphasizing the need for comprehensive measurement tools that capture both hedonic and eudaimonic aspects of well-being. Furthermore, the review discusses the relationship between well-being and academic achievement, underscoring the reciprocal nature of this association. It also explores the impact of social support networks, emotional intelligence, and coping strategies on well-being outcomes, emphasizing the importance of fostering open communication channels and providing access to support services for students. Moreover, the review addresses emerging challenges and opportunities in the field, such as the growing recognition of mental health literacy as a public health goal and the increasing use of technology, including social media and virtual reality, to assess and enhance well-being. Finally, it discusses relevant policy initiatives, including mental health legislation and educational reforms aimed at promoting student well-being and resilience. Overall, this literature review provides valuable insights into the complex interplay between well-being, education, and mental health, offering implications for research, practice, and policy development in these critical areas.

The impact of ATP-sensitive potassium channel modulation on mitochondria in a Parkinson's disease model using SH-SY5Y cells depends on their differentiation state.

Inward rectifying potassium channels sensitive to ATP levels (KATP) have been the subject of investigation for several decades. Modulators of KATP channels are well-established treatments for metabolic as well as cardiovascular diseases. Experimental studies have also shown the potential of KATP modulation in neurodegenerative disorders. However, to date, data regarding the effects of KATP antagonists/agonists in experiments related to neurodegeneration remain inconsistent. The main source of confusion in evaluating available data seems to be the choice of experimental models. The present study aims to provide a comprehensive understanding of the effects of both opening and blocking KATP channels in two forms of SH-SY5Y cells. Our results offer valuable insights into the significance of metabolic differences between differentiated and non-differentiated SH-SY5Y cells, particularly in the context of glibenclamide and diazoxide effects under normal conditions and during the initiation of pathological events simulating Parkinson's disease in vitro. We emphasize the analysis of mitochondrial functions and changes in mitochondrial network morphology. The heightened protein expression of KATP channels identified in non-differentiated SH-SY5Y cells seems to be a platform for a more significant impact of KATP modulators in this cell type. The efficiency of rotenone treatment in inducing morphological changes in the mitochondrial network depends on the differentiation status of SH-SY5Y cells.

Quality Coordinators' Perspectives on Quality Improvement in Primary Healthcare in Kosovo: A Qualitative Study.

This qualitative descriptive study provides insights into the experiences of quality coordinators (QCs) in primary healthcare to inform policy and practice actions and empower QCs to enhance healthcare quality. We conducted focus group discussions with purposefully selected QCs to understand their motivations, job experiences, factors influencing healthcare quality, and suggestions for quality improvement. Content analysis and deductive coding were used to scrutinize the responses and answer the research questions. The QCs thought highly about their job performance and were motivated by both extrinsic and intrinsic factors. Clinical audits, collegial reviews, and managerial support positively affected QCs' performance. In contrast, a lack of managerial support, limited working hours, and changes in organizing work caused the opposite. Empowerment and external support positively influenced healthcare quality, whereas lack of resources, managerial support, or training had a negative influence. Suggestions to improve quality include the role of QCs, external supervision, and centralization of the QCs' network. Appointing QCs alone does not guarantee quality improvement. It is essential to ensure that QCs have the appropriate skills, tools, management support, and open communication channels. Further research is required to evaluate the effects of sex and age on QCs' performance.

A Review of Studying the Flow Characteristics in Branching Open Channels

A Review of Studying the Flow Characteristics in Branching Open Channels

A Versatile Synthesis Platform Based on Polymer Cubosomes for a Library of Highly Ordered Nanoporous Metal Oxides Particles.

Polymer cubosomes (PCs) have well-defined inverse bicontinuous cubic mesophases formed by amphiphilic block copolymer bilayers. The open hydrophilic channels, large periods, and robust physical properties of PCs are advantageous to many host-guest interactions and yet not fully exploited, especially in the fields of functional nanomaterials. Here, the self-assembly of poly(ethylene oxide)-block-polystyrene block copolymers is systematically investigated and a series of robust PCs is developed via a cosolvent method. Ordered nanoporous metal oxide particles are obtained by selectively filling the hydrophilic channels of PCs via an impregnation strategy, followed by a two-step thermal treatment. Based on this versatile PC platform, the general synthesis of a library of ordered porous particles with different pore structures , tunable large pore size (18-78nm), high specific surface areas (up to 123.3m2g-1 for WO3) and diverse framework compositions, such as transition and non-transition metal oxides, rare earth chloride oxides, perovskite, pyrochlore, and high-entropy metal oxides is demonstrated. As typical materials obtained via this method, ordered porous WO3 particles have the advantages of open continuous structure and semiconducting properties, thus showing superior gas sensing performances toward hydrogen sulfide.

Efficient and quantum‐secure authenticated key exchange scheme for mobile satellite communication networks

SummaryThe mobile satellite communication (MSC) system is a vital communication method in which mobile users and network control centers connect via satellites. Since the satellite's communication is wireless, communication security is a critical factor to ensure accountable communication. Key exchange and authentication (KEA) mechanism is widely used to achieve data security for data transmitted in an insecure or open channel. Different authentication systems are suggested in the last many years to establish safe communication, whereas most existing security protocols are based on factorization or discrete logarithm. However, these systems are no longer reliable by Shor's algorithm as any discrete logarithm and factorization can be resolved in polynomial time on quantum computers. Thus, developing a quantum secure KEA protocol for MSC systems is necessary. In this direction, recently a ring learning with an error‐based KEA technique is proposed to ensure a quantum‐safe environment. This scheme is quantum‐safe and satisfies desirable security attributes but has low efficiency in computation and communication. Moreover, establishing a secure session requires six communications among involved entities. As a result, replay attack detection at an early stage is not possible for the central authority (server), which could delay the server response, and the adversary gets the advantage of drawing a denial of service scenario for authorized entities. We propose a lattice‐based KEA protocol for the MSC system to improve computation, communication efficiency, and early‐stage replay attack detection. The security analysis of the proposed scheme is presented in the random oracle model. Calculation of performance is also presented to observe advantages in computation and communication overhead.