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Due to the rapid advancement of GPU computing, deep learning has lately been widely used in image denoising. Most deep learning methods require noise-free images as labels, which are often difficult or impossible to obtain. Therefore, denoising network models have to be trained with a pair of noisy and low-noise images. However, the restored images still face the problem of losing detail information. In this paper, we propose a novel denoising network model based on the concept of Noise2Noise (N2N), where pairs of noisy images are utilized to train a neural network that can learn the noise distribution relationship between them. This newly-proposed model (RA-UNet) draws inspiration from the classical UNet architecture and is designed with a multi-Residual convolutional block with Attention that can adapt different scales to mine the key information of images and recover clearer images. The denoising performance of RA-UNet is comparable and better than that of the conventional CBM3D, while the proposed RA-UNet performs significantly better on both PSNR and SSIM with less 2.5 % FLOPs and less 3 % running time compared to existing deep learning-based methods, such as DnCNN and ADNet. From the perspective of visual quality, RA-UNet can restore images with higher clarity. Compared with the UNet model, our model improves the average PSNR and SSIM obtained by testing Gaussian noise ( σ = 50 ) images on four classic datasets by 2.28 dB and 0.0552, respectively. [ABSTRACT FROM AUTHOR]

Highlights • The spreading characteristics of cyber rumors over mobile social networks are addressed. • A new compartmental compartmental model for cyber rumor spreading is developed. • Rumor-denier's behavior of refuting rumors is incorporated. • The dynamic properties of the model are analyzed. • Numerical simulations illustrate theoretical results and indicate suggestions for inhibiting rumours spreading. Abstract By incorporating the spreading characteristics of cyber rumors over mobile social networks, we newly develop a dynamic system to model rumor spreading dynamics by the compartment method. Specifically, a couple of a user and an attached device is viewed as a node, and all network nodes are separated into four compartments: Rumor-Neutral, Rumor-Received, Rumor-Believed and Rumor-Denied. Some transition parameters among these groups are introduced. Additionally, the role of memory, user's ability to distinguish the rumors and rumor-denier's behavior of refuting rumors are also incorporated. The stability of the equilibria of the model system is addressed, and the influence of model parameters upon the threshold is analyzed. Finally, numerical simulations illustrate the theoretical results, and also motivate us to propose suitable measures to control cyber rumor spreading by properly adjusting the parameter values. [ABSTRACT FROM AUTHOR]

This paper mainly focuses on studying the influence of network characteristics on malware spreading. Firstly, a generalized model with weakly-protected and strongly-protected susceptible nodes is developed by considering the possibility of an intruded node converting back to a weakly-protected susceptible one. The dynamics of the generalized compartmental model is intensively discussed and analyzed, deriving several sufficient conditions for its global stability. Following this work, a novel node-based model is newly proposed to describe malware propagation over an arbitrary connected network including synthesized and real networks. From a microscopic perspective, we establish the novel model by introducing several different variables for each node which describe the probabilities of a node locating at respective states. Our theoretical analysis shows that the largest eigenvalue of the propagating network is a key factor determining malware prevalence. Specifically, the range of the leading eigenvalue can be split into three subintervals in which malware approaches extinction very quickly, or tends to extinction, or persists, depending on into which subinterval the largest eigenvalue of the propagating network falls. Theoretically, the trivial equilibrium of our new node-based model is clearly proved to be exponentially globally stable when the maximum eigenvalue is less than a threshold. We also illustrate the predictive effectiveness of our model by designing some numerical simulations on some regular and scale-free networks. Consequently, we conclude that malware prevalence can be effectively prevented by properly adjusting the spreading network, e.g., reducing the number of nodes and deleting some edges, so that its maximum eigenvalue falls into the appropriate subinterval. [ABSTRACT FROM AUTHOR]

The complex properties of real-world systems have been found in a wide range of physical and social networks. In this paper, a novel network-based model is developed to theoretically address the structure impact of scale-free networks on epidemic web malware spreading. We further split the compartments of the SDIRS model in terms of node degree, and apply the degree-based mean-field approach to formulate the model. The spreading threshold of the new model is explicitly calculated, and the global stability of the malware-free equilibrium is theoretically addressed provided the threshold below unity. Numerical simulations are given to illustrate the theoretical results. Moreover, the dynamics around the malware equilibrium and parameter analysis are also discussed by designing some numerical examples. The predictions are generally in agreement with numerical simulation results. Consequently, we suggest that web malware can be availably contained by properly adjusting the network structure so that the propagation threshold is less than unity. [ABSTRACT FROM AUTHOR]

The immunities of computers against malware are actually heterogeneous depending upon the level of secure protection, which is largely determined by the security awareness of users. To understand the effects this can have on the propagation of malicious software, we herein develop a new compartmental model that takes into account heterogeneous immunization of the computer. In terms of protection levels, the traditional susceptible compartment is newly separated into two sub-compartments, weakly-protected and strongly-protected. Besides, our model includes two assumptions: a computer immediately possesses infectivity once it is infected by malware, and weakly-protected susceptible computers have a higher infection rate than strongly-protected susceptible computers. Appropriate Lyapunov functions are introduced to fully analyze the qualitative properties of this model. Specifically, it is proved that the malware-free equilibrium is globally asymptotically stable if the threshold is below unit, whereas the malware equilibrium is globally asymptotically stable if the threshold is above unit. Furthermore, the sensitivity of each parameter on the model’s threshold is also analyzed. Through numerical simulations, a collection of effective measures for controlling malware spread is proposed, such as keeping as many systems strongly-protected as possible. These findings suggest that the security awareness of users should be taken both in the interpretation of malware parameters, as well as in the prediction of the evolution of future malware outbreaks. [ABSTRACT FROM AUTHOR]

In this paper we investigate the stability of neural networks with time-delay and variable-time impulses. A valid approach on calculating the upper bound and lower bound of dwell time is proposed, which is crucial contribution of this paper comparing to previous results on the stability of neural networks with variable-time impulses. Some reasonable sufficient conditions on guaranteeing the global stability of variable-time impulsive neural networks are introduced. These results are also generalized to the case of fixed-time impulse by taking neural networks with fixed-time impulses as the specific form of variable-time impulsive neural networks. Finally, numerical examples are also given to illustrate the effectiveness of our theoretical results. [ABSTRACT FROM AUTHOR]

Abstract: This paper applies the part-metric method to study some types of higher-order symmetric difference equations with several different exponential parameters. These difference equations are proved to have unique equilibria and some useful inequalities regarding the difference equation functions are formulated. By use of the part-metric and a result given by Kruse and Nesemann (1999) [8], some sufficient conditions on the parameters are given to guarantee the global asymptotic stability of the equilibria. Furthermore, by the part-metric defined on matrices, this approach is also applicable to show the global asymptotic stability of some cyclic discrete dynamic systems. The results of this paper are considered a big improvement over many existing results found in the literature. [Copyright &y& Elsevier]

Abstract: The boundedness and global asymptotic behavior of positive solutions of the nonlinear two-dimensional difference systems , where are all positive integers, are investigated. Some sufficient conditions are established such that the positive solutions converge to the unique equilibrium. Finally, some examples are given to illustrate our results. [Copyright &y& Elsevier]

Abstract: This paper studies a family of nonautonomous max-type difference equations with several delays. Using some transformations we prove global attractivity of positive solutions to these equations under some conditions. Some of our results considerably extend related ones in the literature. Two examples are given to illustrate the main results. [Copyright &y& Elsevier]

We adapt the part metric and use it in studying positive solutions of a certain family of discrete dynamic systems. Some examples are presented, and we also compare some results in the literature. [ABSTRACT FROM AUTHOR]

• Conduct THM growth of CZT crystal using different Te solution heights. • Study the distribution of CZT in Te solvents at different heights. • The growth interfaces correlated with different Te inclusions were revealed. • The value of H/D = 1.0 is optimal for the growth of high-quality CdZnTe crystals. Nowadays, Traveling Heater Method (THM) is demonstrated to be one of the most promising ways to grow high-quality CdZnTe (CZT) crystals. The THM is essentially a melt-solution growth method, in which the CZT solute diffuses from the dissolution interface to the growth interface in the Te solution and deposits on the CZT seed. In this work, the effects of Te solution volumes on the structure of CZT solute, growth interface, defects and electrical properties of CZT crystals grown by THM were investigated. CZT crystals (φ30 × 80 mm3) were grown by THM with different volumes of Te solution (H/D = 1.5, 1, and 0.5, where H is the height and D is the diameter of Te solution). The distribution and morphology of CZT solutes in different Te solutions were investigated, which shown that the large-sized CZT solute in Te solution is more conducive to single-crystal growth and the growth temperature is calculated to be 806–809 °C. The growth interfaces correlated with Te inclusions in the as-grown CZT crystals were revealed, which shown that the CZT crystal grown with Te solution of H/D = 1 has a planar growth interface and the lowest Te concentration. The size of Te inclusion is mainly in the range of 3–10 μm in all CZT crystals grown by THM. The IR transmittance of different CZT wafers was conducted in the range of 4000–500 cm−1. The resistivity and energy spectra of CZT detectors under 241Am irradiation were measured at room temperature. The experiment results demonstrated that the Te solution volume with H/D = 1.0 is optimal for the stable growth of high-quality CZT crystals by THM. [ABSTRACT FROM AUTHOR]

The popularity of the Web improves the growth of web threats. Formulating mathematical models for accurate prediction of malicious propagation over networks is of great importance. The aim of this paper is to understand the propagation mechanisms of web malware and the impact of human intervention on the spread of malicious hyperlinks. Considering the characteristics of web malware, a new differential epidemic model which extends the traditional SIR model by adding another delitescent compartment is proposed to address the spreading behavior of malicious links over networks. The spreading threshold of the model system is calculated, and the dynamics of the model is theoretically analyzed. Moreover, the optimal control theory is employed to study malware immunization strategies, aiming to keep the total economic loss of security investment and infection loss as low as possible. The existence and uniqueness of the results concerning the optimality system are confirmed. Finally, numerical simulations show that the spread of malware links can be controlled effectively with proper control strategy of specific parameter choice. [ABSTRACT FROM AUTHOR]

Stateful authenticated group key exchange (stAGKE) represents an important class of authenticated group key exchange (AGKE) such as tree-based AGKE. The computation of either ephemeral public key or session key in a new stAGKE session may be based on the ephemeral secret state from some previously established session. We notice that earlier AGKE models may be not able to provide appropriate security arguments for stAGKE. In this work, a new model is proposed for stAGKE to formulate security properties in particular for resistance to the leakage attacks on ephemeral key. To be of independent interest, the new model is also flexible, which can be used for analyzing either stateless or stateful AGKE protocols. We show the validity of our model by introducing a new tree-based protocol construction for stAGKE. The proposed scheme is proven secure in our new proposed model without random oracles. [ABSTRACT FROM AUTHOR]

Security proofs are invaluable formal criteria in assuring practitioners on the security properties of protocols. However, one could obtain various security results while proving the considered protocol in different security models. We notice that there are some security proof problems caused by randomized authentication primitives (RAP) in the recent authenticated key exchange (AKE) protocols. Those RAP problems would simply invalidate the security result of such protocols in the corresponding security models. Unfortunately, we figure out that some previous AKE protocols overlooked the RAP problem in their security analysis. We also introduce general solution ideas and concrete examples to avoid RAP problem. [ABSTRACT FROM AUTHOR]

As the phenomenon of knowledge overload becomes more and more obvious, the automatic summarization technology still needs to break through the bottleneck in order to improve the application value and expand the scope of the application. Traditional training paradigms for extractive summarization systems suffer from the inconsistency in training and evaluation. In this paper, we propose an innovative and interpretable contrastive learning based framework for extractive summarization called DCDSum , which comprises a D iverse Oracle evaluator, a C ontrastive learning extractor, and a D ynamic Top-k selector. Different from previous models that consider the extractive summarization task as a sequence labeling problem, our contrastive learning extractor treats it as a sentence reranking problem and introduces contrastive loss to achieve it, which can bridge the gap between objective function and evaluation metrics. The experimental results demonstrate the outstanding performance of our approach on the CNN/DailyMail, XSum, and PubMed datasets, achieving highly competitive results. In particular, our method achieves ROUGE-1 of 44.65, ROUGE-2 of 21.32, and ROUGE-L of 40.87 on the CNN/DailyMail dataset. The outcomes across various evaluation metrics substantiate that the Diverse Oracle extraction algorithm adeptly captures a broader array of sentences with reduced redundancy, consequently enhancing the interpretability of the DCDSum framework. [ABSTRACT FROM AUTHOR]

Wind shear is a dangerous atmospheric phenomenon in aviation. Wind shear is defined as a sudden change of speed or direction of the wind. In order to analyze the influence of wind shear on the efficiency of the airplane, this paper proposes a mathematical model of point target rain echo and weather target signal echo based on Doppler effect. The wind field model is developed in this paper, and the antenna model is also studied by using Bessel function. The spectrum distribution of symmetric and asymmetric wind fields is researched by using the mathematical model proposed in this paper. The simulation results are in accordance with radial velocity component, and the simulation results also confirm the correctness of the established model of antenna. [ABSTRACT FROM AUTHOR]

Abstract: This paper aims to explore the influence of vaccination on the diffusion of computer viruses under more reasonable assumptions. By incorporating a vaccination probability in the SIRS model with generalized nonlinear incidence rate, a novel epidemic model of computer viruses is established. A thorough analysis of this model shows that, depending on the value of the basic reproduction number, either the virus-free equilibrium or the endemic equilibrium is globally asymptotically stable. Simulation results not only justify the proposed model, but also demonstrate the effectiveness of vaccination. Based on a parameter analysis for the model, some effective strategies for inhibiting the virus prevalence are posed. [Copyright &y& Elsevier]

The output and grade of liquid potash minerals in Qarhan Salt Lake are decreasing year by year, which has become the main problem restricting the sustainable production of potassium fertilizer. The exploitation and utilization of low-grade solid potash ore, which is in the strata of the Qarhan Salt Lake, represents the fundamental framework for the sustainable development of Qarhan Salt Lake's potash fertilizer. PHREEQC is a simulation software for hydrogeochemistry. In this paper, PHREEQC was applied to simulate temperature, pH value and solvent chemical characteristics which affect the dissolution process of low-grade solid potash minerals. The simulation results indicate that the optimum temperature for ore dissolution is around 25 °C, because, around this temperature, the dissolving ability of solvents to low-grade solid potash minerals is enhanced, while the dissolving ability to halite remains basically unchanged, which is conducive to selective dissolution of low-grade solid potash. It is recommended the temperature is between 20 and 30 ℃. The simulation results show that, when the pH value of solvents is more than 9, although it is advantageous to selective dissolution of low-grade solid potash minerals, the solvent becomes strong alkali solution, which will cause environmental pollution and seriously corrode materials and equipment in actual production, so it is recommended the pH value of the solvent is adjusted between 6 and 8. The simulation results show that, when the values of K+, Na+, Mg2+, Ca2+, Cl− and SO42− in the solvent are 0.1%, 2.9%, 3.77%, 0.05%, 15.72% and 0.13% respectively, the solubility of low-grade solid potash ores is stronger, which is more conducive to selective ore dissolution. It is suggested that in actual production, the chemical composition of solvents prepared with old brine and fresh water should be as close as possible to the above chemical composition characteristics. [ABSTRACT FROM AUTHOR]

China is one country in the world with the largest potash fertilizer-demand. Potash has been listed as one of the seven strategic resources in China for a long time. Qarhan Salt Lake is the earliest discovered large-scale potash deposit in China. It is a comprehensive deposit dominated by liquid potash resource with the coexistence of solid potash minerals (polyhalite, carnallite, sylvite) and other beneficial elements. It is the largest potash fertilizer production base in China. However, with the increase in production year by year, its potash reserves which reach industrial grade are decreasing continuously, and the sustainable production of potash fertilizer faces a severe reserve shortage. So it is particularly noteworthy to us that there are still 296 million tonnes of low-grade solid potash minerals in Qarhan Salt Lake, which have potential utilization value. These low-grade solid potash minerals are equivalent to a superlarge potash deposit. In this paper, we review the efforts to increase potash supply, to upgrade the industrial structures and to promote the healthy and sustainable development of the potash fertilizer industry in Qarhan Salt Lake, then discuss the process of exploitation and utilization of low-grade solid potash minerals, and the problems encountered, finally proposed the corresponding countermeasures suggestions. [ABSTRACT FROM AUTHOR]

This paper investigates the globally exponential stability of switched neural networks with time-varying delays. By virtue of mode-dependent average dwell time, some significant criteria of exponential stability are obtained for delayed switched neural networks with only stable subsystems or with both stable subsystems and unstable subsystems. The proposed theoretical results could be utilized not only to verify the globally exponential stability of switched neural networks, but also to design appropriate switching signal to guarantee the globally exponential stabilization. They can explicitly reflect the effect of mode-dependent average dwell time on the stability of switched neural networks. In contrast to the previous results, the proposed criteria are more straightforward and effective in the real-world application. Three numerical examples are introduced to illustrate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

This paper studies the reachability realization problem of discrete-time switched linear systems. A new constructive approach is developed to design switching sequence such that the reachable subspace is realized. Compared with the existing results, the length of the designed switching sequence is smaller and the proposed algorithm has fewer calculations. One numerical example is presented to illustrate the effectiveness of the obtained results. [ABSTRACT FROM AUTHOR]

This paper investigates the exponential synchronization of chaotic systems with time delays via periodically intermittent control. Under the new differential inequality, some novel synchronization criteria are derived. In contrast to the existing works, the proposed results are less conservative because they can obtain more precise synchronized rate under the identical control conditions and remove the restrictions on the control period (or the control width) and the time delay. By using special parameters, the feasible region D(ξ), which guarantees the response system synchronizes with the drive system with synchronized rate 0.5ξ, is obtained. The Lu chaotic attractor and a first-order chaotic system with time delay are presented to demonstrate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

This paper investigates the stability of a class of variable-time switched systems whose switching times are dependent on system states. To overcome the difficulty that switching times are not explicit, we construct a new fixed-time switched impulsive system whose stability is equivalent to the stability of the variable-time switched system. In the light of the mode-dependent average dwell time and the constructed fixed-time switched impulsive systems, sufficient conditions for exponential stability of variable-time switched systems are obtained. Finally, two applications are employed to indicate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

In order to analyze the channel estimation performance of near space high altitude platform station (HAPS) in wireless communication system, the structure and formation of HAPS are studied in this paper. The traditional Least Squares (LS) channel estimation method and Singular Value Decomposition-Linear Minimum Mean-Squared (SVD-LMMS) channel estimation method are compared and investigated. A novel channel estimation method and model are proposed. The channel estimation performance of HAPS is studied deeply. The simulation and theoretical analysis results show that the performance of the proposed method is better than the traditional methods. The lower Bit Error Rate (BER) and higher Signal Noise Ratio (SNR) can be obtained by the proposed method compared with the LS and SVD-LMMS methods. [ABSTRACT FROM AUTHOR]

This paper is devoted to exploring the combined impact of a generic nonlinear infection rate and infected removable storage media on viral spread. For that purpose, a novel dynamical model with an external compartment is proposed, and the explanations of the main model assumptions (especially the generic nonlinear infection rate) are also examined. The existence and global stability of the unique equilibrium of the model are fully investigated, from which it can be seen that computer virus would persist. On this basis, a next-best approach to controlling the level of infected computers is suggested, and the theoretical analysis of optimal control of the model is also performed. Additionally, some numerical examples are given to illustrate the main results. [ABSTRACT FROM AUTHOR]

This paper studies some human immunodeficiency virus (HIV) models with switching parameters and pulse control. The classical virus dynamics model is first modified by incorporating switching parameters which are assumed to be time-varying. Some threshold conditions are derived to guarantee the virus elimination by utilizing a Razumikhin-type approach. The results show that the proper switching conditions chosen can increase the counts of CD4+ T-cells while reducing viral load. Pulse control strategies are then applied to the above model. More precisely, the treatment strategy and the vaccination strategy are applied to infected cells and uninfected cells, respectively. Each control strategy is analyzed to gauge its success in achieving viral suppression. Numerical simulations are performed to complement the analytical results and motivate future directions. [ABSTRACT FROM AUTHOR]

Land colonization is a major event in plant evolution. Little is known about the evolutionary characteristics of lipids during this process. Here, we proved that Physcomitrella patens , a bryophyte that appeared in the early evolution of terrestrial plants, has short-term desiccation resistance. The maintenance of membrane integrity is related to its specific glycerolipid composition and key genes for lipid metabolism. We analyzed 414 types of lipid molecules, and found that phospholipids accounted for 61.7%, mainly PC and PI; glycolipids accounted for only 26.5%, with a special MGDG molecular map. The most abundant MDGD, that is, MGDG34:6, contained rare 15- and 19-carbon acyl chains; the level of neutral lipids was higher. This was consistent with the results observed by TEM, with fewer lamellae and obvious lipid droplets. Slight dehydration accumulated a large number of TAG molecules, and severe dehydration degraded phospholipids and caused membrane leakage, but PA and MGDG fluctuated less. The key genes of lipid metabolism, DGAT and PAP , were actively transcribed, suggesting that PA was one of the main DAG sources for TAG synthesis. This work proves that Physcomitrella patens adopts high-constitutive PC and PI similar to plant seeds, abundant TAG, and its own specific MGDG to resist extreme dehydration. This result provides a new insight into the lipid evolution of early terrestrial plants against unfavorable terrestrial environments. [Display omitted] • Short-term desiccation resistance naturally exists in Physcomitrella patens. • Highly constitutive PC and PI similar to plant seeds. • Specific MGDG map, the most dominant lipid species contains two odd-numbered acyl chains. • Rapid dehydration accumulates TAG and stimulates the pathway from PA to DAG. • The specific glycerolipid composition establishes the dehydration tolerance of early land plants. [ABSTRACT FROM AUTHOR]

• Multi-tracer models are applicable to constrain the solute mass balance & water budget in the mega-brine lakes. • Hydrothermal groundwater discharge delivers disproportionate Li and B loadings to the brine lake. • Ra-226 is dominated by co-precipitation in the lake, with a coefficient of 4.72 to 6.07 y−1. Brine lakes are good natural laboratories to investigate groundwater influences on the hydrologic and chemical evolutions in arid environments, and the mineralization processes under intensive evaporation. Lacustrine groundwater discharge (LGD) is the vital conveyor for the loadings of resource elements in the brine lakes. Da Qaidam Lake, located in the Qaidam basin of the Qinghai–Tibet Plateau (QTP), is one of the largest brine lakes for boron and lithium resources in China. Lithium and boron in the lake are considered to be dominantly sourced from deep hydrothermal groundwater and shallow groundwater, but the partitioning of deep and shallow components to the lake and the derived lithium and boron loadings remain unknown, LGD derived boron and lithium provide the primary source of the salt lake. vitally regulates the formation, evolution and mineralization of Li and B resources in the brine lake. This study performs systematical investigations of radium isotopes (226Ra, 228Ra, 224Ra and 223Ra), lithium, boron, and other hydrogeochemical parameters in different water endmembers around the brine lake. The results indicate that radium isotopes are significantly enriched in the hydrothermal groundwater and will be removed by co-precipitation with barite precipitates in the lake water. The multi-tracer models coupled radium bass balance, conservative tracer buildup and water budget were deployed to precisely constrain radium co-precipitation rates, and to quantify the deep and shallow LGD (total LGD = LGD D + LGD S) and the derived lithium and boron loadings. Radium co-precipitation coefficient is obtained to be 4.7–6.1 y−1. LGD D and total LGD are estimated to be 8.8 × 106 and 3.3 × 107 m3 y−1, respectively, which account for 11.9% and 57.2% of the total water input. LGD D and total LGD derived lithium/boron loadings constitute up to 70.2/60.1%, and 79.0/77.7% of the total loadings, respectively, indicating the significance of disproportionate LGD D in delivering resource elements into the brine lake. This study presents the first attempt to partition the deep hydrothermal and shallow LGD to a mega the QTP brine lake by multi-tracer models and the findings contribute to the understanding of lithium and boron budgets in the brine lakes of the QTP and worldwide. [ABSTRACT FROM AUTHOR]

Qarhan Salt Lake contains approximately 296 million tonnes of low-grade solid potash ores. The exploitation and utilization of this low-grade solid potash ore represents the fundamental framework for the sustainable development of Qarhan Salt Lake's potash fertilizer industry. It also alleviates the shortage of potash resources of China. In this paper, we studied species and characteristics of the low-grade solid potash minerals from the Bieletan area in Qarhan Salt Lake and analyzed the solvent that affected the dissolution extraction of low-grade solid potash ore. The major potash minerals in the Bieletan Subbasin are polyhalite, carnallite and sylvite. An effective solvent for dissolving these potash minerals is prepared with old bittern and water from Senie Lake, which contains average Mg2+, Cl−, K+ and Na+ values as 3.69%, 15.23%, 0.23% and 1.60%, respectively. Theoretically calculating by PHREEQC shows that the chemical composition of the solvent is nearly in equilibrium with halite and far away from equilibrium with polyhalite, carnallite and sylvite. This solvent does not significantly cause dissolution and precipitation of halite. Thus its influence on the porosity and permeability of the salt bed in the strata is minimum, which enables the solvent to flow to deeper and farther areas and dissolve more low-grade solid potash ores, showing excellent ability to selectively dissolve K+-bearing saline minerals. After dissolution extraction experiments, the concentration of K+ in the solvent increased from 0.23% to 0.68%, showing the higher-dissolution effect of the solvent for the low-solid potash ores. Hence, the solvent plays an important role in developing of the low-grade potash ores. • The low-grade potash mineral in Bieletan of Qarhan Salt Lake is polyhalite, followed by carnallite and a small amount of sylvite. • The solvent for dissolution extraction of low-grade solid potash ore was prepared with old bittern and natural fresh water, with Mg2+, Cl-, K+ and Na+ geochemical average values of 3.69%, 15.23%, 0.23% and 1.60%, respectively. • The solvent did not influence the porosity and permeability of the salt layer, could flow to deeper and farther areas, and could dissolve more low-grade solid potash minerals. • After dissolution extraction of low-grade solid potash ore, the content of K+ in the solution increased from 0.23% to 0.68%. [ABSTRACT FROM AUTHOR]