Monotonic Structure Research Articles

The Influence of Contemporary Architecture on The Shape of Library Buildings and Fine Arts Education Facilities in Surabaya

A library and fine arts educational facility is an educational place to gain knowledge and introduce fine arts. Through observations, the researcher identified issues in Surabaya's libraries, such as the monotonous building structures and unattractive spatial atmosphere. Meanwhile, fine arts facilities lack resources for making art, so the integration of a library and fine arts education facility is necessary in one location. In this building, visitors can not only gain knowledge about art but also increase their creativity by learning while making works of art with artists. It serves as a solution to increase the reading interest index and introduce works of art more widely.The application of a contemporary architectural theme is based on the expressive characteristics of educational and artistic buildings, following current contemporary characteristics. Qualitative research with a descriptive approach depicts the experiences in the field, which were then analyzed using parameters of the function and feasibility of educational and artistic buildings.The design of the library and fine arts education facility applies the contemporary architecture theme to the macro concept of recreational education to provide a special attraction to visitors.The shape design uses an attractive micro concept by giving the building an identity through variations of curved lines, geometric shapes inspired by a book, and bright color combinations derived from mosaic paintings.

Exploration Noise for Learning Linear-Quadratic Mean Field Games

The goal of this paper is to demonstrate that common noise may serve as an exploration noise for learning the solution of a mean field game. This concept is here exemplified through a toy linear-quadratic model, for which a suitable form of common noise has already been proven to restore existence and uniqueness. We here go one step further and prove that the same form of common noise may force the convergence of the learning algorithm called fictitious play, and this without any further potential or monotone structure. Several numerical examples are provided to support our theoretical analysis. Funding: F. Delarue acknowledges the financial support of the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme [AdG ELISA project, Grant 101054746]. A. Vasileiadis acknowledge the financial support of French ANR project ANR-19-P3IA-0002-3IA Côte d'Azur-Nice-Interdisciplinary Institute for Artificial Intelligence.

On the approximability and energy-flow modeling of the electric vehicle sharing problem

The electric vehicle sharing problem (EVSP) arises from the planning and operation of one-way electric car-sharing systems. It aims to maximize the total rental time of a fleet of electric vehicles while ensuring that all the demands of the customer are fulfilled. In this paper, we first show that the EVSP is NP-hard to approximate to within a factor of n1−ϵ in polynomial time, for any ϵ>0, where n denotes the number of customers. In addition, we also show that the problem does not have a monotone structure, which can be detrimental to the development of heuristics employing constructive strategies. Moreover, we propose a novel approach for modeling the EVSP based on energy flows. Based on this new model, we propose a relax-and-fix strategy and an exact algorithm. Our computational results show that our formulation outperforms the previous best-performing formulation in the literature in the number of optimal solutions obtained, optimality gaps, and computational times. Previously, 32.7% of the instances remained unsolved (within a time limit of one hour), while our formulation obtained optimal solutions for all instances. To stress our approaches, two more challenging new sets of instances are generated, for which we can solve 49.5% of the instances, with an average optimality gap of 2.91% for those not solved optimally.

A bioinspired heterostructured nanochannel based on dendrimer-gold network and aluminum oxide arrays for sensitive detection of miRNA

BackgroundMicroRNAs, as oncogenes or tumor suppressors, enable to up or down-regulate gene expression during tumorigenesis. The detection of miRNAs with high sensitivity is crucial for the early diagnosis of cancer. Inspired by biological ion channels, artificial nanochannels are considered as an excellent biosensing platform with relatively high sensitivity and stability. The current nanochannel biosensors are mainly based on homogeneous membranes, and their monotonous structure and functionality limit its further development. Therefore, it is necessary to develop a heterostructured nanochannel with high ionic current rectification to achieve highly sensitive miRNA detection. ResultsIn this work, an asymmetric heterostructured nanochannel constructed from dendrimer-gold nanoparticles network and anodic aluminum oxide are designed through an interfacial super-assembly method, which can regulate ion transport and achieve sensitive detection of target miRNA. The symmetry breaking is demonstrated to endow the heterostructured nanochannels with an outstanding ionic current rectification performance. Arising from the change of surface charges in the nanochannels triggered by DNA cascade signal amplification in solution, the proposed heterogeneous nanochannels exhibits excellent DNA-regulated ionic current response. Relying on the nucleic acid's hybridization and configuration transformation, the target miRNA-122 associated with liver cancer can be indirectly quantified with a detection limit of 1 fM and a wide dynamic range from 1 fM to 10 pM. The correlation fitting coefficient R2 of the calibration curve can reach to 0.996. The experimental results show that the method has a good recovery rate (98%–105 %) in synthetic samples. SignificanceThis study reveals how the surface charge density of nanochannels regulate the ionic current response in the heterostructured nanochannels. The designed heterogeneous nanochannels not only possess high ionic current rectification property, but also enable to induce superior transport performance by the variation of surface chemistry. The proposed biosensor is promising for applications in early diagnosis of cancers, life science research, and single-entity electrochemical detection.

Stability of traveling wavefronts for advection–reaction–diffusion equation

In this paper, we study an advection–reaction–diffusion equation, where the nonlinear advection has neither monotonicity nor variational structure. For all wavefronts with the speed c>c0, where c0 is the minimal wave speed, we use the technical weighted energy method to prove that these wavefronts are exponentially stable, when the initial perturbations are small in a weighted Sobolev space.

Plant community differentiation of desertification region in northwest Liaoning Province, China

Understanding plant communities in desertification area is the scientific basis of evaluating the local eco-environmental quality and carrying out desertification control. According to longitude, we divided the desertification area in northwest Liaoning Province into three regions: the eastern region (122°50'37″ -123°49'40″ E), the middle region (121°16'41″-122°35'00″ E), and the western region (119°20'03″ -120°02'41″ E), and investigated the plant communities in each region. The results showed that the proportion of forest and canopy density of tree layer increased from the west to the east. Ass. Pinus sylvestris var. mongolica and Ass. Populus sp. in the eastern, Ass. Pinus tabuliformis and Ass. Populus sp. in the middle, as well as Ass. P. tabuliformis and Ass. Prunus sibirica in the western were dominant communities, respectively. The proportion of brush community in the eastern, middle and western was 0, 22.2%, and 28.0%, respectively. Grasslands formed mainly by human disturbance in the eas-tern and middle regions. The total species numbers were 110 in the middle, 88 in the western and 75 in the eastern, respectively. Therophytes were dominant in the eastern and middle with proportions of 68.2% and 66.7%, respectively. Hemicryptophytes were the dominant type (36.3%) in the western region. The proportion of microphanerophyt, nanophanerophyte, chamaephyte, and geophyte increased from the eastern to the western. The species number, Shannon index, and Simpson diversity index of the middle were the highest among the three regions. Pielou evenness index increased gradually from the eastern to the western. Community similarity between the eastern and the western was the lowest, as shown by the β-biodiversity, and the similarity between the middle and the western was the highest. The community type, species number, characteristics of species composition and species biodiversity of the middle region had the characteristics of ecological transition zone. In general, vegetation status in the desertification area of northwest Liaoning Province was in good condition. There were still some problems including the monotonous vertical structure of forest and tree species as well as the serious human interference.

Engineering self-assembled 2D nano-network membranes through hierarchical phase separation for efficient air filtration

Air pollution has garnered significant worldwide attention; however, the existing air filtration materials still suffer from issues related to monotonous structure and the inherent trade-off between PM rejection and air permeability. Herein, a spider web-inspired composite membrane with continuous monolayer structured 2D nano-networks tightly welded on nanofibers in the electrospun membrane scaffold is designed via a hierarchical phase separation strategy. The resultant biomimetic hierarchical-structured membranes possess the integrated features of hierarchical multiscale structures of 2D ultrafine networks composed of nanowires with a diameter of 31 nm self-assembled by nanoparticles, exceptional characteristics involving small average aperture, extremely low network thickness, high porosity and promising pore channel connectivity, combined with rich surface polar functional groups (3.02D dipole moment). Consequently, the composite membrane exhibits a high PM0.3 capture efficiency of 99.6 % and low pressure drop of 58.8 Pa, less than 0.06 % of atmosphere pressure, with outstanding long-term PM2.5 recycling filtration performance. The hierarchical phase separation–driven 2D nano-networks construction strategy, by virtue of their feasibility and tunability, holds great promise for widespread application across diverse membrane-related domains for air filtration.

Estimating a Preference-Based Value Set for the Mental Health Quality of Life Questionnaire (MHQoL).

Health economic evaluations using common health-related quality of life measures may fall short in adequately measuring and valuing the benefits of mental health care interventions. The Mental Health Quality of Life questionnaire (MHQoL) is a standardized, self-administered mental health-related quality of life instrument covering 7 dimensions known to be relevant across and valued highly by people with mental health problems. The aim of this study was to derive a Dutch value set for the MHQoL to facilitate its use in cost-utility analyses. The value set was estimated using a discrete choice experiment (DCE) with duration that accommodated nonlinear time preferences. The DCE was embedded in a web-based self-complete survey and administered to a representative sample (N = 1,308) of the Dutch adult population. The matched pairwise choice tasks were created using a Bayesian heterogeneous D-efficient design. The overall DCE design comprised 10 different subdesigns, with each subdesign containing 15 matched pairwise choice tasks. Each participant was asked to complete 1 of the subdesigns to which they were randomly assigned. The obtained coefficients indicated that "physical health,""mood," and "relationships" were the most important dimensions. All coefficients were in the expected direction and reflected the monotonic structure of the MHQoL, except for level 2 of the dimension "future." The predicted values for the MHQoL ranged from -0.741 for the worst state to 1 for the best state. This study derived a Dutch value set for the recently introduced MHQoL. This value set allows for the generation of an index value for all MHQoL states on a QALY scale and may hence be used in Dutch cost-utility analyses of mental healthcare interventions. A discrete choice experiment was used to derive a Dutch value set for the MHQoL.This allows the use of the MHQoL in Dutch cost-utility analyses.The dimensions physical health, mood, and relationships were the most important.The utility values range from -0.741 for the worst state to 1 for the best state.

Admission and routing control of multiple queues with multiple types of customers

We study the routing and admission control problem in a parallel queueing system with heterogeneous servers serving multiple types of customers. The system makes admission decision regarding whether to admit a customer upon arrival as well as routing decision of the queue to which the admitted customer is assigned. The objective is to maximize the expected profit, which includes customer-dependent revenues and holding cost and server-dependent cost. We first characterize the structure of the optimal policy for the case with two servers and two types of customers that have the same holding cost. We show that the optimal admission and routing policy has a complex non-monotone structure; however, we show that this non-monotone structure is the result of overlapping of three pairwise dominant policies that have a monotone structure. Utilizing the above structure, we propose three heuristics for the general case of multiple servers and multiple types of customers. Through a numerical study, we demonstrate the effectiveness of our heuristics, and provide conditions under which each heuristic performs well. Lastly, we provide insights on the effect of holding cost on customer rejection and the effect of fixed production cost on capacity allocation.

Quasilinear Dirichlet systems with competing operators and convection

In this paper, we consider a quasi-linear Dirichlet system with possible competing (p,q)-Laplacians and convections. Due to the lack of ellipticity, monotonicity, and variational structure, the standard approaches to the existence of weak solutions cannot be adopted. Nevertheless, through an approximation procedure and a corollary of Brouwer's fixed point theorem we show that the problem admits a solution in a suitable sense.

Stability analysis of linear ion waves leading to nonlinear shock and soliton structures in a dense quantum plasma with strongly coupled ions and degenerate electrons

In a quantum plasma with strongly coupled ions and Fermi degenerate electron fluids, features of low frequency wave dispersion and nonlinear electrostatic structure formation are explored. Dynamics of strongly coupled ions is considered through a generalized momentum balance equation over the visco-elastic relaxation time for ion correlations and viscosity of ion fluid through shear. Quantum forces associated with degenerate electron fluid include many-particle effect of exchange-correlations, quantum statistical-pressure and quantum recoil effect. The system supports dispersive shock and soliton structures regulated by the Korteweg-de Vries Burger equation and modified-Korteweg-de Varies equation, respectively which are derived and solved analytically. Only monotonic shock structures are observed for a given value of the Burger factorμ. For solitary structures, the amplitude and width depend upon quantum dispersive effects of electrons.

Optimal power control for sensors and DoS attackers over a fading channel network

In this paper, we focus on the optimal power control for the sensors and attackers in a remote state estimation process, which guarantees the achievement of the estimation task under the denial-of-service (DoS) attack. In the remote estimation process under the DoS attack, each sensor observes the target state and transmits its local estimates to the remote estimator via a wireless network, communications in which are disrupted by jamming signals. For the wireless network, while most of the existing works on the resilient remote state estimation consider time-invariant channel state information (CSI) model, we pay attention to the fading channel network, in which the channel state is fixed and the channel model can be characterized by a generalized finite-state Markov chain. We model the conflicting nature among the sensor and the attacker as a general-sum stochastic game, proposing a Nash Q-learning algorithm to find the optimal power control strategies for the two players. Moreover, the monotone structure of these strategies is constructed with a sufficient condition. Taking into account the practical applications, we also consider the case where the sensor and the attacker only know partial information of each other and employ the Bayesian game to model it. Based on the channel information of each player and its believes of the channel distribution of the opponent, the type-contingent energy strategies are obtained. Finally, simulation results are given to verify our results.

Linear port-Hamiltonian DAE systems revisited

Port-Hamiltonian systems theory provides a systematic methodology for the modeling, simulation and control of multi-physics systems. The incorporation of algebraic constraints has led to a multitude of definitions of port-Hamiltonian differential–algebraic equations (DAE) systems in the literature. This paper presents extensions of results obtained in Gernandt et al. (2021); Mehrmann and van der Schaft (2023) in the context of maximally monotone structures, and shows that any such structure can be written as the composition of a Dirac and a resistive structure. This yields an alternative, but equivalent, definition of linear port-Hamiltonian DAE systems with certain advantages. In particular, it leads to simpler coordinate representations, as well as to explicit expressions for the associated transfer functions.

Efficient Solar-osmotic Power Generation from Bioinspired Anti-fouling 2D WS2 Composite Membranes.

Nanofluidic reverse electrodialysis provides an attractive way to harvest osmotic energy. However, most attention was paid to monotonous membrane structure optimization to promote selective ion transport, while the role of external fields and relevant mechanisms are rarely explored. Here, we demonstrate a Kevlar-toughened tungsten disulfide (WS2) composite membrane with bioinspired serosa-mimetic structures as an efficient osmotic energy generator coupling light. As a result, the output power could be up to 16.43 W m-2under irradiation, outperforming traditional two-dimensional (2D) membranes. Both the experiment and simulation uncover that the generated photothermal and photoelectronic effects could synergistically promote the confined ion transport process. In addition, this membrane also possesses great anti-fouling properties, endowing its practical application. This work paves new avenues for sustainable power generation by coupling solar energy.

Efficient Solar‐osmotic Power Generation from Bioinspired Anti‐fouling 2D WS2 Composite Membranes

AbstractNanofluidic reverse electrodialysis provides an attractive way to harvest osmotic energy. However, most attention was paid to monotonous membrane structure optimization to promote selective ion transport, while the role of external fields and relevant mechanisms are rarely explored. Here, we demonstrate a Kevlar‐toughened tungsten disulfide (WS2) composite membrane with bioinspired serosa‐mimetic structures as an efficient osmotic energy generator coupling light. As a result, the output power could be up to 16.43 W m−2 under irradiation, outperforming traditional two‐dimensional (2D) membranes. Both the experiment and simulation uncover that the generated photothermal and photoelectronic effects could synergistically promote the confined ion transport process. In addition, this membrane also possesses great anti‐fouling properties, endowing its practical application. This work paves new avenues for sustainable power generation by coupling solar energy.

Flame-retardant, ultralight, and superelastic electrospun fiber sponges for effective sound absorption

Traffic noise does great harm to the physical and mental health of humans, which has become the main source of noise pollution, making sound absorption materials highly in demand. Fibrous sound-absorbing materials are widely used in controlling traffic noise pollution; nevertheless, due to the monotonic internal structure and large fiber diameter, they suffer poor mechanical properties and sound absorption performance. Herein, we develop a credible way to create flame-retardant fibrous sound absorption sponges by humidity-assisted electrospinning and an in-situ crosslinking approach. The obtained fibrous sponges possess outstanding superelastic and hydrophobic properties. Most importantly, fluffy fiber networks endow sponges with good low-frequency sound-absorbing properties (noise reduction coefficient or NRC of 0.51) and lightweight features (density of 9 mg cm−3) compared with commercial and reported sound-absorbing materials. This work will shed light on future research in developing excellent sound-absorbing materials.

Monotone Data Modelling Using Rational Cubic Fractal Interpolation Function

Geometric modelling of several intricate and complex structures such as trees, mountains, clouds, ferns, geographic topography, and coastlines is challenging in computer graphics. Traditional splines such astrigonometric, polynomial, exponential, and rational fail to simulate this significant class of complex structures, which are highly irregular in nature. For this purpose, this research develops a novel cutting-edgemethod for synthesizing and modelling structures. The proposed technique; C 1 fractal interpolation function (FIF) builds an iterated function system (IFS) by integrating fractal calculus and rational cubic polynomial functions. Appropriate conditions on scaling and shape parameters are derived to help maintain the inherited shape qualities of the data. Experiments in numerous scientific domains, such as the pharmaceutical and chemical industries have been presented as an example, to confirm the usefulness of the suggested model. Moreover, the graphic results demonstrated that the developed monotone hybrid model (MHM) offers a heterogeneous method for gathering data with a monotone structure.

Submodularity of optimal sensor placement for traffic networks

The need for monitoring the state of a traffic network versus the costly installation and maintenance of roadside sensors constitutes the tough sensor placement problem in designing transportation networks. Placement problems naturally lie in the category of subset selection problems, which are known to be inherently combinatorial, and therefore, finding their exact solution is intractable for large problems. Due to this intractability, numerous heuristics have been proposed in the literature for approximately solving placement problems for traffic networks. Among these approaches, it has been observed that greedy algorithms normally outperform other heuristics. In this paper, we show the mathematics of why greedy algorithms are appropriate proxies for solving these subset selection problems; similar to placement problems for linear systems, placement problems for traffic networks also normally have a submodular structure. In this work, we analyze the problem of road sensor placement for transportation networks under different information structures available: when no vehicle routing information is available, when vehicles’ routings are known, and when it is necessary to maximize the number of origin–destination (O/D) traffic flows that are monitored with a set of sensors. We show that in all these cases, the placement problem has a submodular monotone structure. It is well known that the submodularity and monotonicity of discrete optimization problems can be leveraged to derive greedy algorithms that approximate the optimal solution. Consequently, our result is of great practical importance since by exploiting the submodularity and monotonicity of a problem, we show that it is possible to use polynomial-time greedy algorithms to approximate the combinatorial optimization problem with guaranteed optimality bounds for large problems, which are intractable to solve otherwise. Our results shed light upon the success of heuristic greedy algorithms that have been developed in some of the literature for solving placement problems at scale. To demonstrate the applicability of submodular optimization for solving placement problems, we first compare the performance of our polynomial-time approximation algorithm with the true optimum in an example traffic network which is small enough for finding the exact optimal solution with enumerating all possible subsets. Then, we investigate and validate our submodular approach in a case study involving a large-scale traffic network in Berkeley, California, where finding the exact optimal solution is intractable. Submodularity of the placement problem in these scenarios provides a powerful computational tool which can be further extended to other placement problem formulations that can become a reference for solving similar problems in the transportation literature.

PIRAP: Intelligent Hybrid Approach for Secure Data Transmission in Wireless Sensor Networks

The wireless sensor network (WSN) is a mobile adhoc network which has no support of infrastructure. The complexities in network management are critical to resolve even when choosing the cluster head is more efficient. From clustering procedure, appropriate cluster heads are selected with attention to energy saving among member nodes. When it comes to WSN security, trust-based cluster head selection is critical, assuming the cooperation of all sensor nodes. In light of this assumption, existing approaches were unable to assist in identifying the network’s ideal cluster head. Due to the dynamic topology and mobility of nodes in WSNs, security is a challenge. However, secrecy is often accomplished end-to-end via symmetric keys between two corresponding applications. The symmetric key is incompatible with the WSN environment. Additionally, the WSN nodes vary in their qualification for which portion of the data is accessible in which context. This work proposes an elliptic curve cryptography-enabled ciphertext policy attribute-based encryption (ECC-CP-ABE) algorithm for secure data transmission during intra-cluster communication and inter-cluster communication. In this work, we select a reliable node-based trust value mechanism and this reliable node acts as an attribute authority that inter-cluster provides a decryption private key to cluster members who are involved in intra- and inter-cluster communications. In ECC-CP-ABE, the cluster head node (CHN) and cluster member node (CMN) utilize CP-ABE for the encryption of network messages using an access policy matrix A that is computed from an AND–OR operation-based monotonic tree access structure which is defined over a various set of attributes. To ensure authenticity and integrity, the cluster member and CHN sign each ciphertext using an ECC algorithm. For performance evaluation, we use packet delivery ratio, energy consumption, encryption time, network lifetime, and decryption time as metric measures and compared the results of proposed ECC-CP-ABE with two benchmark methods, Secured WSN and Taylor-based Cat Salp Swarm Algorithm. From the results, we analyze that the proposed ECC-CP-ABE reduces energy consumption by 53.2%; increases packet delivery ratio by 98.6%; increases network lifespan by 97.5%, and reduces encryption time by 20[Formula: see text]s and decryption time by 15[Formula: see text]s.

Symmetry of Periodic Traveling Waves for Nonlocal Dispersive Equations

Of concern is the a priori symmetry of traveling wave solutions of a general class of nonlocal dispersive equations , where is a Fourier multiplier operator with symbol . Our analysis includes both homogeneous and inhomogeneous symbols. We characterize a large class of symbols guaranteeing that periodic traveling wave solutions are symmetric under a mild assumption on the wave profile. In contrast with the classically imposed setting in the water wave problem which assumes traveling waves to have a unique crest and trough per period or a monotone structure near troughs, we formulate a reflection criterion which does not presuppose a monotone structure on the wave profile. Thereby, the reflection criterion enables us to treat a priori solutions with multiple crests of different size per period. Moreover, our result applies not only to smooth traveling wave solutions, but also to those with singular crests around which some cancellation structure appears, including in particular waves with peaks or cusps. The proof relies on a so-called touching lemma, which is related to a strong maximum principle for elliptic operators, and a weak form of the celebrated method of moving planes.