The Impact of Bullwhip Effect on the Cash Flow in Two-Parallel Supply Chain Systems with the Competition Effect

While considering the competition effect and market share, this study discusses how the cash flow bullwhip effect (CFBE) is impacted in two-product and two-parallel supply chain systems by comparing the situation that it has one kind of product in two-level supply chain (SC). Specifically, the study aimed to examine two-product and two-parallel SC systems that include two suppliers and two retailers. Assuming that the demand function is a linear relationship of price self-sensitivity coefficient and price cross-sensitivity coefficient, which is an AR(1) process, two retailers share the demand. After that, the quantitative equation of the CFBE was deduced from two-product and two-parallel SC systems. Finally, we get the condition that the competition effect and the market share increase or decrease the CFBE, which was in contrast to the situation without the competition effect and the market share. The paper suggested that the manager can cooperate with their partner if two products are substitutable. On the other hand, the firm should improve the forecasting accuracy of the customer’s demand and improve the service quality so that it can increase the market share and reduce the CFBE in two-parallel SC systems.

Pricing Strategies of Registration System and Transaction System in Live Broadcast Platform

This paper investigates a supply chain consisting of the monopoly live broadcast platform, content producers, and consumers. Based on the two-sided market theory, the platform’s pricing strategies and their analysis are considered under the registration system and the transaction system. Firstly, it shows that platform users’ scale and profit are positively correlated with the intergroup network externality from both sides and the intragroup network externality inside the consumer group and negatively correlated with the intragroup network externality inside the content producer group. Secondly, the platform profit, registration fee charged to content producers, and transaction fee charged to consumers are negatively correlated to the content production cost and positively related to consumers’ content quality sensitivity coefficient. When consumers are more sensitive to content quality, they are positively correlated to content quality. Finally, the registration fee charged by the platform to consumers is positively correlated with the content production cost, negatively correlated with the content quality level, and positively associated with the consumer content quality sensitivity coefficient.

Plastic deformation behavior and constitutive modeling of Cu-50Ta alloy during hot compression

This paper presents a study on plastic deformation behavior of Cu–50Ta alloy at temperatures of 286–473 K and strain-rate of 0.01–6200 s−1. The effects of temperature, strain-rate, and strain on the yield strength, flow stress, and strain-rate sensitivity coefficient were determined. A phenomenological model was established to predict variation of the strain-rate sensitivity coefficient for Cu–50Ta alloy under dynamic compression. A Johnson–Cook constitutive model was established to predict the equivalent stress–equivalent plastic strain relationship under extreme deformation (high temperature and strain-rate). The results showed that the plastic deformation behavior of Cu–50Ta alloy was affected by temperature, strain-rate, and strain. The material exhibited obvious strain-rate strengthening and thermal softening. As the strain-rate increased, the yield strength logarithmically increased. At a temperature of 286 K, the strain-rate increased from 0.01 s−1 to 6200 s−1, and the yield strength increased from 543.75 MPa to 881.13 MPa. In addition, the yield strength linearly decreased as the deformation temperature increased. Under conditions of dynamic deformation, the variation of strain-rate sensitivity coefficient could be expressed as a function of strain-rate and strain. The phenomenological model accurately described the variation of the strain-rate sensitivity coefficient of Cu–50Ta under dynamic deformation conditions. The Johnson–Cook constitutive parameters, calibrated by experimental data, described the plastic deformation behavior of the alloy under high-velocity impact.

Design Optimization of Sensitivity-Enhanced Structure for Fiber Bragg Grating Acoustic Emission Sensor Based on Additive Manufacturing

A four-loop shaped structure of fiber Bragg grating (FBG) acoustic emission (AE) sensor based on additive manufacturing (AM) technology is proposed in the letter. The finite element analysis (FEA) method was used to model and analyze the sensor structure. We aimed at improving the sensitivity, the static load analysis, and the dynamic response analysis of the normal FBG acoustic emission sensor and the FBG AE sensor with improved structure parameters. We constructed the FBG AE sensor experimental system based on a narrowband laser demodulation method and test on real acoustic emission signals. The results demonstrated that the response sensitivity of the FBG acoustic emission sensor was 1.47 times higher than the sensitivity of the normal FBG sensor. The sensitivity coefficient of PLA-AE-FBG2 sensor was 3.057, and that of PLA-AE-FBG1 was 2.0702. Through structural design and parameter optimization, the sensitivity and stability of the FBG AE sensor are improved. The four-loop shaped sensor is more suitable for the health monitoring in fields such as aero-engine blade, micro-crack of structure, and crack growth in bonded joints. While ensuring the sensing characteristics, sensitivity, and stability of the four-loop shaped sensor have been enhanced. It is possible to apply the FBG AE sensor in some complex engineering environments.

The Coordination of Multi-Stage Discounts in a Dual Channel Fresh Agricultural Pro-duce Supply Chain: Minimizing the Loss of Quantity and Quality

This paper explores the coordination of the agricultural cooperative to supermarket or E-commerce sup-ply chain, under the condition of quantity loss with a mixed decay function of exponential and logistical distribution. The nature of this process is analyzed, and the corresponding demand and supply functions with single- and multi-stage discount strategies are constructed respectively to create a working model. The optimal discount ratios for supermarkets and agricultural cooperatives in decentralized and central-ized decision-making modes coupled with single- and multi-stage discounts are calculated respectively. Finally, a universal optimal strategy is designed, which can be applied to various quantity decay scenarios and makes the discount strategy more generalized. The results show that discounts can coordinate supply chains more effectively; not only is fresh agricultural produce sold before it starts to rot, but the benefit conflicts arising from both supermarkets vs. cooperatives and traditional vs. E-commerce channels are equilibrated. Further, multi-stage discounts are more effective than single-stage ones, but optimal discount ratios rely on the initial quantity of fresh agricultural produce in the supply chain; its market share in the traditional distribution channel; the potential market size; retail price; the price sensitivity coefficient of the channel; the cross-elasticity coefficient of prices between different channels; and the properties of the quantity loss.

Sensitivity Analysis Strategy to Assess the Salting-Out Problem during CO2 Geological Storage Process

The sensitivity analysis of the salting-out effect on well injectivity is a significant work in the research of geological storage of CO2 in deep saline aquifers, which is helpful in the selection of storage sites and the design of the injection strategy. We conduct a detailed sensitivity analysis about the salting-out process using the local sensitivity method and two global sensitivity methods. Sensitivity coefficients showed that brine salinity (XNaCl) has the highest sensitivity and interaction effect, the CO2 injection rate (QCO2) has a greater influence in the early stage of the salting-out process and a smaller influence in the end stage, and the other three parameters (empirical parameters related to the pore distribution m, the liquid residual saturation in the relative permeability function Splr, and the liquid residual saturation in the capillary pressure function Sclr) have a smaller sensitivity. This paper also analyzes the calculation amount of different sensitivity methods and suitable ways of obtaining the sensitivity coefficient and reveals the following. (1) The sensitivity coefficient changes dynamically with time, if only the sensitivity of the final state is taken into account on a long-time physical process, and some sensitive parameters during the process may be neglected. (2) The selection of the sample size should be based on the convergence of multiple calculations, and the results of the empirical calculation are uncertain. (3) The calculation of Sobol sensitivity is complicated, the results calculated by surrogate model depend on whether the sample is representative enough; on the other hand, it is feasible to use Sti-Si approximation to characterize the second-order sensitivity to reduce the computation. The research results not only reveal the sensitivity of the parameters related to the injection well salting-out problem during CO2 storage in deep saline aquifers but also guide the calculation of global sensitivity analysis with a similar physical process.

A highly stable temperature sensor based on Au/Cu/n-Si Schottky barrier diodes depending on the inner metal thickness

We have fabricated the Au/n-Si (D1), Au/Cu/n-Si (D2), Au/Cu(4nm)/n-Si (D3) and Au/Cu(2nm)/n-Si (D4) Schottky-barrier diodes (SBDs). The thickness of the Cu Schottky contact (SC) films for the D2, D3, and D4 diodes has been chosen as 100, 4 and 2 nm, respectively. We have investigated the thermal sensitivity from the voltage-temperature (V-T) characteristics of the SBDs at different current levels. The V-T measurements have been made in the temperature range from 10 K to 320 K with steps of 2 K, at the different current levels from 50 nA to 141.70 µA. The V-T curves have shown a good linearity degree for all SBDs. The slope dV/dT = α or thermal sensitivity coefficient α for each diode has decreased with increasing current level from 50 nA to 141.70 µA. But, it has been seen that the SBDs with the Cu SC have approximately the same α value as independent of metal thickness at the same current level. That is, the thermal sensitivity coefficient value has changed approximately from 2.48 mV/K at 50 nA to 1.82 at 141.70 µA for the SBDs with Cu Schottky contact as independent metal thickness. Furthermore, the α versus current level plots of the diodes have exhibited a linear behavior. The intercept α0 and slope dα/dI values of the α versus current level plots have been obtained as 2.80 mV/K and -0.0843 mV/(AK) for D2, and 2.85 mV/K and -0.092 mV/(AK) for D3 and 2.83 mV/K and -0.0876 mV/(AK) for D4. These values are very close to each other and the difference between the slope (dα/dI) values is small enough to be neglected.

Considering the Sales Method and Logistics Service Strategy, Which Operating Mode Is the Best under Different Power Structures?

When merchants enter hybrid e-commerce platforms (such as JD.com and Amazon), they will face issues such as which sales methods to choose and whether to use platform logistics under different power structures. Different sales methods and logistics service strategies have resulted in three operating modes: (a) resale mode, marked as A, (b) agency + no-platform logistics, marked as B, and (c) agency + platform logistics, marked as C. This paper constructs an analysis framework composed of an e-commerce platform and a merchant to explore the optimal operating mode. The game models of the three modes are first constructed, and then, the equilibrium results are compared and analysed. Based on the results of comparative analysis and considering the dynamic game between the e-commerce platform and the merchant regarding sales methods and logistics service strategies, the optimal operating mode is determined. The results show that when the platform has absolute power, mode C is optimal for it. When the logistics service sensitivity coefficient and market size are both large, the best for the merchant with absolute power is mode B. In addition, if neither of them has absolute power, only when the merchant first decides the logistics service strategy, then the platform decides the sales method; the best for both parties is mode B; otherwise, the best is mode A. This research has generated new insights and has practical management significance, which can provide guidance for merchant and platform decision-making.

Grassland Phenology’s Sensitivity to Extreme Climate Indices in the Sichuan Province, Western China

Depending on the vegetation type, extreme climate and drought events have a greater impact on the end of the season (EOS) and start of the season (SOS). This study investigated the spatial and temporal distribution characteristics of grassland phenology and its responses to seasonal and extreme climate changes in Sichuan Province from 2001 to 2020. Based on the data from 38 meteorological stations in Sichuan Province, this study calculated the 15 extreme climate indices recommended by the Expert Team on Climate Change Detection and Indices (ETCCDI). The results showed that SOS was concentrated in mid-March to mid-May (80–140 d), and 61.83% of the area showed a significant advancing trend, with a rate of 0–1.5 d/a. The EOS was concentrated between 270–330 d, from late September to late November, and 71.32% showed a delayed trend. SOS was strongly influenced by the diurnal temperature range (DTR), yearly maximum consecutive five-day precipitation (RX5), and the temperature vegetation dryness index (TVDI), while EOS was most influenced by the yearly minimum daily temperature (TNN), yearly mean temperature (TEMP_MEAN), and TVDI. The RX5 day index showed an overall positive sensitivity coefficient for SOS. TNN index showed a positive sensitivity coefficient for EOS. TVDI showed positive and negative sensitivities for SOS and EOS, respectively. This suggests that extreme climate change, if it causes an increase in vegetation SOS, may also cause an increase in vegetation EOS. This research can provide a scientific basis for developing regional vegetation restoration and disaster prediction strategies in Sichuan Province.

Supply Chain Decision Analysis of Community E-Commerce Platform under Different Power Structures: Considering the Influence of Value Cocreation

In order to explore the impact of different decision-making methods on the profits of various entities in the supply chain of the community e-commerce platform, this paper adopts the method of the Stackelberg game. For the community e-commerce platform supply chain composed of suppliers, community e-commerce platforms, and grid station service providers, considering the degree of supplier value cocreation efforts, this paper studies the optimal decisions under centralized decision-making, supplier-led decentralized decision-making, and community e-commerce platform-led decentralized decision-making, respectively. The results show that the supply chain obtains the highest profit in centralized decision-making; under decentralized decision-making, the dominant party will get higher profits; and the supplier value cocreation sensitivity coefficient is positively correlated with sales price, value cocreation effort level, and total supply chain value. The results are helpful to improve the competitiveness of the community e-commerce platform supply chain in the market and are of great significance to the long-term development of the community e-commerce industry.