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Aluminum nanoparticles (nAl) have received sustained interest due to their higher reactivity than micron aluminum particles (mAl). However, in practice, the densities of explosive formulations with nAl are far smaller than those with mAl, which greatly undercuts the energy release performance. To take advantages of both kinds of Al particles, in situ integration of mAl@nAl composites was proposed and evaluated. The mAl@nAl composites were prepared by in situ electrical explosion of Al wire. Their morphology, density, and specific surface area (SSA) were characterized by scanning electron microscope (SEM), densimetry, and Brunauer–Emmett–Teller (BET), respectively. SEM showed that nAl uniformly adhered to the surface of mAl. With the increase in voltage, the average diameter and density of the composites decreased, but the SSA of the composites increased. And the largest density of the composites was 1.13 g/cm3, comparable to that of the commercial graded Al product (1.25 g/cm3). Meanwhile, the highest SSA of the composites was 12.1192 m2/g. In addition, the combustion efficiency of mAl@nAl composites at 20 kV was 8.26% higher than that of physically graded counterparts. The constant-volume combustion test under zero oxygen balance revealed that the pressurization rate and peak pressure of mAl@nAl composites prepared at 20 kV were the highest of all. Furthermore, constant-volume combustion under constant heat showed that the combustion temperatures of mAl@nAl composites were 1.15–1.45 times higher than those of physically graded counterparts. Finally, the ignition delay of mAl@nAl composites was reduced with the increase in explosion voltage. [ABSTRACT FROM AUTHOR]

Online product pricing is an important research field in the platform economy, and a two‐stage mixed presale is a mainstream mode of online sales. In the process of online consumption, the payment method and presale mode have an important impact on consumer behaviour and product pricing. Based on the two‐stage mixed presale mode, this study considers the impact of anchoring and the payment pain reduction effect on consumer behaviour, establishes the corresponding product pricing model and obtains the optimal presale price, sales and profit. It sheds light on the influence mechanism of anchoring and the payment pain reduction effect on consumer behaviour and online product pricing. Theoretical and numerical analyses reveal that the payment pain reduction effect can help to raise the product price, stimulate market vitality and bring higher profits for online retailers, and the anchoring effect and consumers' loss aversion psychology can enhance the profits and sales of online retailers, but they will discourage setting high prices for products. The research results will further enrich the relevant research on customer behaviour and product pricing in the platform economy and will provide decision bases for platform enterprises and online retailers to participate in presale activities and formulate product pricing strategies. [ABSTRACT FROM AUTHOR]

Online product pricing is an important factor that affects the purchase of customers and the earnings of e‐commerce platform enterprises. It has an increasingly prominent influence on consumers' purchasing decisions. To study the influence of customers' anchoring psychology and product pricing on customers' purchasing behaviors, this paper proposes a pricing model that considers online consumers to be anchored by the product price and sales. The cognitive bias of online consumers is described by a utility function based on an anchoring‐adjustment heuristic, and consumer choice behavior and an online product pricing strategy are studied with a multinomial logit model. Then, it studies the influence of the anchoring point and anchoring degree on optimal pricing, sales and profit. In particular, when consumers are anchored only by sales of goods, the optimal solution is monotonic with respect to the anchoring degree. However, when consumers are anchored by both price and sales, both factors affect consumer behaviors and produce more complex results. This paper provides a flexible pricing mechanism for platform enterprises, and it can provide a theoretical basis and decision support for dynamic pricing of platform enterprises based on historical consumption data. [ABSTRACT FROM AUTHOR]

With the rapid development of O2O, offline experience and online purchase have become a method of purchase for more and more customers. Through offline experience, consumers can feel the quality of products directly. Such channel switching behavior of consumers will produce a "showroom" effect and affect the return rate of online channels. This study adopts the multinomial logit model to maximize profits by considering the difference in quality between online and offline products, quality defects, and offline service. Then, a pricing decision model is developed to analyze the influence of returning goods due to quality problems on the retailers' optimal pricing and profit. The result shows that retailers can obtain the optimal profit when the offline service is maintained at a certain level. As the return rate increases, the optimal pricing increases, but the maximum profit decreases. The optimal pricing decreases with the increase in online product quality, but the maximum profit increases accordingly. In the omni-channel environment, customers can freely switch between channels according to utility and preference when purchasing products. Based on customer returns, retailers can dynamically adjust their service, control product quality, and set optimal product pricing, thus achieving maximum profits. This study can provide a theoretical basis and decision support for omni-channel retailers in platform operation and revenue management. [ABSTRACT FROM AUTHOR]

Incorporating consumer choice behavior into a product line design optimization model enhances the understanding of consumer choices and improves the opportunities to increase profit. Most product line optimization problems assume that parameters are precisely known in consumer choice model. However, the decision maker does not precisely know the model parameters because of insufficient sample data, measurement problems, and other factors. We investigate the problem of establishing robust product line pricing under a multinomial logit model to account for the uncertainty of the valuation parameter. First, we present a nominal product line model to maximize profit. We then establish a robust product line model to maximize the worst-case expected profit, where the valuation parameter lies in an uncertainty set. We consider both single and multiple products development and derive the optimal prices' closed-form expressions. Through numerical experiments, we illustrate the benefit of robust product line pricing to address parameter uncertainty. We demonstrate that the difference between the expected nominal profit and the worst-case profit increases with the increase of the interval of the uncertainty set, and the robust profit relative to the worst-case nominal profit improves. The robust product line design can ensure steadier, even higher profit. [ABSTRACT FROM AUTHOR]

With recent developments in information technology and the extensive promotion of Internet Plus, the use of online centralized procurement by governments and enterprise groups has become progressively more common, and the winning bid evaluation decision making method is particularly important in this context. However, experts might not be completely rational during the process of bid evaluation, which may induce the enhancement or repression of bid scores. To address such behaviors during the process of bid evaluation, an automatic mechanism to identify and correct such tendencies is proposed in this study. Because experts have different preferences for different alternatives, which are directly reflected in the evaluation of attribute values. Based on selection preference, this paper proposes a selection preference method for solving the subjective weight of attributes. Firstly, the weights of relevant attributes are first determined via the entropy weight method and the selection preference method, and the weights corresponding to groups are determined according to the differences between the scores assigned by experts. Then, a grouped multi-attribute bid evaluation decision making method is proposed based on the selection preference. Finally, an example is used to verify the effectiveness of the method and its superiority over existing methods. Thus, a theoretical basis and a decision support mechanism are provided in this study for centralized procurement departments of governments and enterprises. Further, it also provides guidance for multi-attribute decision making problems with identical grouped features. [ABSTRACT FROM AUTHOR]

Isothermal thermal decomposition method was used to study the thermal behavior of the HMX-based PBX explosive JOL-1. The gas pressure versus time curves of the isothermal decomposition of JOL-1 were obtained within the temperature range of 90°C to 130°C. Kinetic parameters such as activation energy and frequency factor for the thermal decomposition of JOL-1 were obtained using the Arrhenius equation and model-fitting method. The model-fitting method further proved that the isothermal decomposition of JOL-1 at 90°C, 100°C, 110°C, 120°C, and 130°C is consistent with the No. 8 mechanism function, namely, the anti-Jander equation, controlled by 3D diffusion. The storage life of JOL-1 was estimated by the Semenov equation and the extent of reaction reached 0.1–0.4%. Results showed that the effective storage life of JOL-1 at 25°C, 40°C, and 60°C are 68 years, 10 years, 1 year, respectively, when the extent of reaction reached 0.1%. [ABSTRACT FROM AUTHOR]

Reverse auctions with multiple attributes have been extensively applied for centralized purchasing of large enterprises and governments. This paper focuses on the bid evaluation behaviors of referee experts and employs an evolutionary game approach to improve the fairness and reliability of bid evaluation. First, the bid evaluation process and existing problems in the mechanism are described. Second, a static game model is constructed to analyze the conditions that are necessary for achieving a long-term cooperative equilibrium between business and technical groups. Third, some evolutionary paths and factors influencing bid evaluation behaviors are analyzed, and then a simulation system is developed based on the evolution process and run several times on a MATLAB GUI platform. The simulation results explicitly make a wider gamut of decision-making parameters as well as start-up variants on initial conditions that determine further evolution. The methods and results presented in this paper can provide decision support for administrative departments in the bid evaluations of centralized purchasing. Those bodies can then choose from the best existing management policies to guide the referee experts’ behaviors into the desired channels and toward optimal outcomes. A more judicious bidding evaluations process may result. [ABSTRACT FROM AUTHOR]

This paper investigates the product-positioning problem for a monopolist developing of a new product. The majority of the literature on product positioning assumes that the consumer choice model and parameters are both precisely known. In reality, however, the marketer may be uncertain about the model structure or the parameters due to incomplete information, small sample data size, etc. In this paper, we investigate a robust product-positioning problem based on the multinomial logit model to account for parameter uncertainty. We first establish a nominal product-positioning model, in which valuation parameters are assumed to be known. Then, we investigate a static robust product-positioning problem with the multinomial logit model to obtain the maximin revenue. We also propose a two-period dynamic robust model. For each setting, we consider both homogeneous and heterogeneous customers' preferences. Finally, numerical experiments are presented to compare the nominal model with the static robust model, and to compare the static robust model with the dynamic robust model. The experiments show that when facing uncertain parameters, the robust model obtains more stable revenue than the nominal model; the dynamic robust model obtains higher revenue than the static robust model. [ABSTRACT FROM AUTHOR]

The complex network effect of the product exhibits has a significant impact on the product line optimization design. The multinomial logit (MNL) model which is used to simulate consumer choice behavior is applied in most of product line optimization problems. However, its assumptions, independence of irrelevant alternatives (IIA) and the same Gumbel distribution of random error terms, are usually difficult to be met in practice. The marginal moment model (MMM) can be used when the mean and variance of consumer's utility error are known. The MMM not only has weak assumption conditions but also overcomes the IIA problem of MNL model. In this paper, we study the product pricing problem based on MMM with endogenous negative network effect. Firstly, we construct a variant of MMM considering network effect in product line optimization design. Secondly, we prove that the revenue function is concave in market share. We propose the solving methods of the model to obtain the optimal price, the corresponding market share, and the revenue under three different scenarios, i.e., developing single product, homogeneous products, and heterogeneous products. Finally, numerical experiments show that the proposed model can better simulate consumer choice behavior and potentially increase revenue. [ABSTRACT FROM AUTHOR]

During warhead penetration, which lasts several milliseconds, warheads undertake moderate pressures reaching hundreds of MPa. Previous methods have been unable to mimic such stimuli to evaluate the safety of ammunitions. Hence, new safety evaluation methods with moderate pressures and long durations to assess the stability of the explosive charges during actual penetrations are needed. Based on existing explosives safety estimation technologies and preliminary understanding of overload environments during penetration, a confined impact model was developed. The peak stimuli pressure is more than 0.3 GPa and the duration of the pressure is between 1 to 3 milliseconds. Various scales of a polymer-bonded explosive (PBX-9) were subjected to this confined impact test to study the response characteristics. The ignition mechanism of PBX-9 was obtained by synthesizing results from X-ray photoelectron spectroscopy (XPS), computed tomography (CT) scanning, differential scanning calorimetry (DSC) and thermalgravimetric analysis (TG). It was found that cracks formed on the surface during impact and the initial ignition of PBX-9 is mainly due to the decomposition of Ammonium perchlorate (AP) and hydroxyl-terminated polybutadiene (HTPB) on the interface at low temperature. Our study indicates that the designers of the PBX formulation should try to control the early decomposition of AP and HTPB in order to let the PBX survive the penetration. [ABSTRACT FROM AUTHOR]

Reverse auctions with multiattributes are widely used for centralized procurements of large enterprises and government departments. The bid evaluation mechanism is a key factor for a fair auction and resource allocation. The current bid evaluation process is usually done by two groups, a business expert group and a technical expert group, separately. Taking bounded rationality as a precondition, we analyze the existence of antagonistic feelings between the two groups. The antagonistic feelings may grow as time goes by. To verify the discovered points, a multiagent-based approach is used to simulate the bid evaluation behaviors. The prototype system of a current bid evaluation mechanism is described by a multiagent model. In the model, the behaviors of both auctioneer and bidders are described by the attributes of each agent and decision rules. Their interactions are described by the collaboration and information exchange between different agents. The procedure of multiagent simulation is specifically presented. Then, the multiagent simulation system is developed and repeatedly runs on the platform of MATLAB GUI while adjusting relevant parameters. The results demonstrate that the behaviors of raising and repressing bid scores are increasingly severe with the passage of time. The result is that differences between the two groups increase with a decrease in the objectiveness of experts. The accumulation of antagonistic feelings can be obviously observed. The current mechanism is unfair to the bidders, as it may make the best bid lose the auction. To solve this problem, two modified bid evaluation mechanisms are suggested. The simulation comparison results show that the new bid evaluation mechanisms can efficiently weaken the antagonistic feelings of the two groups. Finally, three constructive suggestions are put forward to the organizer of tendering and bidding. [ABSTRACT FROM PUBLISHER]

Two key issues are confronted by the Port Group when entering an inland-river market; namely, port acquisition selection at the strategic level and port service pricing at the operational level. This article identifies the multi-type game relationships among the Port Group and multiple ports and customers in the planning time-horizon, and proposes a three-level programming model based on repeated games for the inland-river port acquisition selection and service pricing collaborative optimization problem. According to the model characteristics, a three-level nested heuristic algorithm is developed by combining a genetic algorithm, game simulation algorithm and equilibrium allocation algorithm. A series of numerical experiments with partial real data in Jining City, Shandong Province, China, is conducted to validate the superiority and efficiency of the proposed model and method. This article also provides some valuable management suggestions for the inland-river Port Group in terms of investment scale, investment expectation, pricing mode and customer relationship. [ABSTRACT FROM AUTHOR]

Objective: CD147 is an important glycoprotein that participates in the progression of diverse cancers. This study aims to explore the specific function of CD147 in lung adenocarcinoma (LUAD) and to reveal related downstream molecular mechanisms. Methods: Followed by silencing of CD147, the viability, migration, invasion, and apoptosis of LUAD cells were measured by CCK8, wound healing, transwell assay, and flow cytometer, respectively. The expression of CD147 and two markers of lipid metabolism (FASN and ACOX1) were detected by qRT-PCR. A xenograft tumor model was constructed to investigate the function of CD147 in vivo. Then transcriptome sequencing was performed to explore the potential mechanisms. After measuring the expression of Rap1 and p-p38 MAPK/p38 MAPK by western blot, the changes of CD147 and lipid metabolism markers (FASN, ACOX1) was detected by Immunohistochemistry. Moreover, a Rap1 activator and a Rap1 inhibitor were applied for feedback functional experiments. Results: CD147 was up-regulated in LUAD cells, and its silencing inhibited cell proliferation, migration, invasion, lipid metabolism dysregulation and promoted apoptosis, while overexpression of CD147 showed the opposite results. Silencing of CD147 also inhibited the growth of tumor xenografts in mice. Transcriptome sequencing revealed 834 up-regulated differentially expressed genes (DEGs) and 602 down-regulated DEGs. After functional enrichment, the Rap1 signaling pathway was selected as a potential target, which was then verified to be blocked by CD147 silencing. In addition, the treatment of Rap1 activator weakened the inhibiting effects of si-CD147 on the proliferation, migration, invasion, and lipid metabolism in LUAD cells, while the intervention of RAP1 inhibitor showed the opposite results. Conclusions: Silencing of CD147 inhibited the proliferation, migration, invasion, lipid metabolism dysregulation and promoted apoptosis of LUAD cells through blocking the Rap1 signaling pathway. [ABSTRACT FROM AUTHOR]

This correction notice addresses an error in the original article titled "Silencing of CD147 inhibits cell proliferation, migration, invasion, lipid metabolism dysregulation and promotes apoptosis in lung adenocarcinoma via blocking the Rap1 signaling pathway." The authors identified that Figures 1 and 2 were inadvertently swapped. The correction provides the correct figures and captions, and assures readers that the corrections do not alter the interpretations or validity of the research. The error does not significantly impact the overall findings and conclusions of the paper. [Extracted from the article]

Affective computing is one of the key technologies to achieve advanced brain-machine interfacing. It is increasingly concerning research orientation in the field of artificial intelligence. Emotion recognition is closely related to affective computing. Although emotion recognition based on electroencephalogram (EEG) has attracted more and more attention at home and abroad, subject-independent emotion recognition still faces enormous challenges. We proposed a subject-independent emotion recognition algorithm based on dynamic empirical convolutional neural network (DECNN) in view of the challenges. Combining the advantages of empirical mode decomposition (EMD) and differential entropy (DE), we proposed a dynamic differential entropy (DDE) algorithm to extract the features of EEG signals. After that, the extracted DDE features were classified by convolutional neural networks (CNN). Finally, the proposed algorithm is verified on SJTU Emotion EEG Dataset (SEED). In addition, we discuss the brain area closely related to emotion and design the best profile of electrode placements to reduce the calculation and complexity. Experimental results show that the accuracy of this algorithm is 3.53 percent higher than that of the state-of-the-art emotion recognition methods. What's more, we studied the key electrodes for EEG emotion recognition, which is of guiding significance for the development of wearable EEG devices. [ABSTRACT FROM AUTHOR]

ceramics were synthesized by solid-state reaction method, and their magnetic properties and conductive characteristics were investigated and discussed. It is found that La-doped ceramic without doping is a rhombohedrally distorted perovskite structure, and with the increase of the concentration, the phase transits gradually from rhombohedral to pseudo cubic symmetry. Electrical and magnetic properties show strong dependence on dopant level. The measurement demonstrates that with 30% dopant exhibits the lowest values of the leakage current, dielectric constant and dielectric loss . And the highest value of saturation magnetization of about 4.5 emu/g is observed in 60% Sr-doped . An abnormal enhancement of the conductivity was observed in ceramics with = 0.60 and 0.70, and their magnitude of conductivity is nearly six orders larger than that of pure . [ABSTRACT FROM AUTHOR]