The Combination Forecasting Model of Auto Sales Based on Seasonal Index and RBF Neural Network

Lihua Yang,Baolin Li 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.1

To effectively predict auto sales and improve the competitiveness of automotive enterprise, the characteristics of actual auto sales were analyzed, owing to the seasonal fluctuations and the nonlinearity of monthly sales, the combination forecasting model based on seasonal Index and RBF neural network was proposed. The weights of the two single models were computed using mean absolute percentage error and the sum of square error respectively, the result shows that mean absolute percentage error is more effective. Finally, the prediction accuracy of different models was compared based on the criteria of MAPE and RMSE, and the effectiveness of the method was proved, the proposed model can take advantage of the strengths of the two single models, the results indicate that the combination forecasting model suitable for auto sales has high prediction accuracy, which can provide a certain reference to auto sales forecasting.

A Novel SINS/CNS Integrated Navigation Algorithm used in a Ballistic Missile

Lihua Yang,Baolin Li,Lei Ge 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.9

The position and velocity errors are divergent of traditional navigation algorithms used in ballistic missile for it cannot estimate the bias of accelerometer precisely. To solve this problem, a novel SINS/CNS integrated navigation algorithm is proposed in this paper, which adds high angle error, azimuth angle error and height error on the basis of the traditional navigation method. As these three values are related to the position of missile, the proposed method can constrain the divergence of navigation errors. Meanwhile, a system model for ballistic missile is deduced. To verify the navigation precision of the proposed algorithm, the observable analysis and simulation experiments are performed. And the results show that the system state of proposed method is observable completely, and the divergence of navigation error can be restrained thoroughly.

Genome-wide identification of auxin-responsive microRNAs in the poplar stem

Yang Lihua,Ping Tao,Lu Wenjin,Song Sangfa,Wang Jianli,Wang Qiao,Chai Guohua,Bai Yue,Chen Yan 한국유전학회 2023 Genes & Genomics Vol.45 No.8

Background Wood (secondary xylem) of forests is a material of great economic importance. Wood development is strictly controlled by both the phytohormone auxin and microRNAs (miRNAs). Currently, the regulatory mechanisms underlying wood formation by auxin-associated miRNAs remain unclear. Objective This report was designed to identify auxin-responsive miRNAs during wood formation. Methods Morphological observation of wood development in the poplar stems was performed under the treatment of different concentrations (0 mg/L, CK; 5 mg/L, Low; 10 mg/L, High) of indol-3-butyric acid (IBA). Using a small RNA sequencing strategy, the effect of IBA treatment on miRNAs expression was genome-widely analyzed. Results In this study, we found that wood development of poplar was promoted by low concentration of IBA treatment but inhibited by high concentration of IBA treatment. Stringent bioinformatic analysis led to identification of 118 known and 134 novel miRNAs candidates. Sixty-nine unique developmental-related miRNAs, corresponding to 269 target genes, exhibited specific expression patterns in response to auxin, as was consistent with the influence of auxin application on wood formation. Three novel miRNAs had the most number (≥ 9) of target genes, belonging to SPL, GRF and ARF gene families. The evolutionary relationships and tissue expression patterns of 41 SPL, GRF and ARF genes in poplar were thus analyzed. Of them, four representative members and corresponding miRNAs were confirmed using RT-qPCR. Conclusions Our results may be helpful for a better understanding of auxin-induced regulation of wood formation in tree species.

A Novel Combination Forecasting Algorithm Based on Time Series

Lihua Yang,Baolin Li,Xuetao Li,Lvjiang Yin 보안공학연구지원센터 2015 International Journal of Database Theory and Appli Vol.8 No.2

To effectively predict cigarette sales and improve the competitiveness of tobacco business enterprises, the characteristics of actual cigarette sales were detailed analyzed. Due to the long-term growth trends, seasonal fluctuations and the nonlinearity of monthly sales, we established three single forecasting models, which are Exponential Smoothing (ES), Seasonal Decomposition (SD) and Radial Basis Function (RBF) neural network. After obtaining the predicted value of three single models, the combination forecasting model was proposed. The weights of the three single models were computed using Mean Absolute Error and the mean relative error respectively, the result shows that relative error is more effective. A dynamic weight combination forecasting method based on RBF is proposed and compared with fixed weight method. Finally, the prediction accuracy of different models was compared based on the criteria of MAPE and RMSE, and the effectiveness of the combination method was proved, the proposed model can take advantage of the strengths of the three single models, the results indicate that the combination forecasting model suitable for cigarette sales has higher prediction accuracy. In some cases, the prediction accuracy of the fixed weight combination model is better than the dynamic weight combination model. The results can provide a certain reference to cigarette sales forecasting.

A Multi-Criteria Decision-Making Method Using Power Aggregation Operators for Single-valued Neutrosophic Sets

Lihua Yang,Baolin Li 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.2

As a generalization of intuitionistic fuzzy sets, neutrosophic sets (NSs) can be better handle the incomplete, indeterminate and inconsistent information, which have attracted the widespread concerns for researchers. In this paper, some new aggregation operators are proposed under single-valued neutrosophic environment. Firstly, the definition and operational laws of single-valued neutrosophic numbers (SVNNs) are introduced. Then, the single-valued neutrosophic power average (SVNPA) operator and the single- valued neutrosophic power weighted average (SVNPWA) operator are developed, and some properties of SVNPWA operator are also analyzed. Furthermore, a method for solving multi-criteria decision-making (MCDM) problems is explored based on the power aggregation operators and cosine similarity measures. Finally, an illustrative example is shown to verify the effectiveness and practicality of the proposed method.

Sum rate and Energy Efficiency of Massive MIMO Downlink with Channel Aging in Time Varying Ricean Fading Channel

( Lihua Yang ),( Longxiang Yang ),( Hongbo Zhu ),( Yan Liang ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.3

Achievable sum rate and energy efficiency (EE) are investigated for the massive multiple-input multiple-output (Massive MIMO) downlink with channel aging in the time varying Ricean fading channel. Specifically, the expression of the achievable sum rate of the system for the maximum ratio transmission (MRT) precoder with aged channel state information (CSI) in the time varying Ricean fading channel is first presented. Based on the expression, the effect of both channel aging and the Ricean factor on the power scaling law are studied. It is found that the transmit power of base station (BS) is scaled down by 1/√M (where M is the number of the BS antennas) when the Ricean factor K is equal to zero (i.e., time varying Rayleigh fading channel), indicating that aged CSI does not affect the power scaling law. However, the transmit power of the BS is scaled down by for the time varying Ricean fading channel (where K≠0) indicating that the Ricean factor affects the power scaling law and sum rate, and channel aging only leads to a reduction of the sum rate. Second, the EE of the system is analyzed based on the general power consumption model. Both the theoretical analysis and the simulations show that the channel aging could degrade the sum rate and the EE of the system, and it does not affect the power scaling law.

Environmental Regulation, Institutional Distance and China’s Outward Foreign Direct Investment in the Belt and Road Countries

Lihua Yang,Qi Chen,Huaqiang Su 한국무역연구원 2023 무역연구 Vol.19 No.6

Purpose – This study aims to explore the direct impact of environmental regulation on outward foreign direct investment (OFDI), and the moderating role of institutional distance in the relationship between the two, focusing on China’s OFDI in 58 countries along the Belt and Road (BRCs) during the period 2003-2021. Design/Methodology/Approach – The fixed effects model, DID model and panel threshold model are adopted in the basic estimation and heterogeneity tests. Findings – The results show that environmental regulation has a significant positive impact on China’s OFDI into the BRCs, and institutional distance has strengthened this positive impact. But this moderating effect can only be detected when the institutional distance is positive. Comparative analysis before and after the Belt and Road Initiative (BRI) showed that the impact of environmental regulation on China’s OFDI was greater after BRI than before BRI. Furthermore, the significant impact of environmental regulation on OFDI could only be observed in countries with relatively stringent environmental regulation. Threshold tests found that there is a threshold value in the impact of environmental regulation on OFDI. The DID estimation results showed that when the institutional level and environmental regulation level of the host country are lower than that of China, the BRI plays a greater role in promoting China’s OFDI into the BRCs. Research Implications – The findings have significant implications for understanding how China’s OFDI responds to the environmental regulation of the host countries, simultaneously considering the impact of institutional distance.

Iterative Channel Estimation for MIMO-OFDM System in Fast Time-Varying Channels

( Lihua Yang ),( Longxiang Yang ),( Yan Liang ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.9

A practical iterative channel estimation technique is proposed for the multiple-input-multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system in the high-speed mobile environment, such as high speed railway scenario. In the iterative algorithm, the Kalman filter and data detection are jointed to estimate the time-varying channel, where the detection error is considered as part of the noise in the Kalman recursion in each iteration to reduce the effect of the detection error propagation. Moreover, the employed Kalman filter is from the canonical state space model, which does not include the parameters of the autoregressive (AR) model, so the proposed method does not need to estimate the parameters of AR model, whose accuracy affects the convergence speed. Simulation results show that the proposed method is robust to the fast time-varying channel, and it can obtain more gains compared with the available methods.

Local and Distortional Interaction Buckling of Cold-formed Thin-Walled High Strength Lipped Channel Columns

Lihua Huang,Wenbin Yang,Tingwei Shi,Jiting Qu 한국강구조학회 2021 International Journal of Steel Structures Vol.21 No.1

In this paper, a series of axial compression tests were conducted on lipped channel columns constructed from cold-formed high strength Grade G550 steel sheet of thickness of 1 mm in order to investigate the local and distortional interaction buckling performance. The failure modes, ultimate loads and load–displacement curves of the specimens were reported and analyzed. The experiment revealed the deformation mechanism of specimens failing in local-distortional interaction or distortional mode. Besides, a fi nite element model was developed to predict the buckling performance of the specimens. The eff ect of diff erent imperfection shapes and material models on numerical results was investigated so that the reasonable fi nite element analysis can be carried out. It was found that the local buckling mode with an odd number of waves as the initial imperfection can produce practical deformation process. Meanwhile, the material model of Ramberg–Osgood can be applied for the nonlinear fi nite element analysis of the specimens. The parametric analysis was also performed to study the relationship between the sensitivity of specimens to local and distortional imperfections as well as the variation of bearing capacity with the geometric size. It was found that the lip width has great infl uence on the bearing capacity of specimens because of the signifi cant restriction of lip on distortional deformation.

Effects of Phytosterol Ester on the Fatty Acid Profiles in Rats with Nonalcoholic Fatty Liver Disease

Lihua Song,Haiyue Zhou,Wenjuan Yu,Xinwen Ding,Li Yang,Jiayi Wu,Chenwei Song 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.2

Both serum and hepatic fatty acid (FA) compositions differ among nonalcoholic hepatic steatosis, nonalcoholic steatohepatitis, and healthy subjects. The severity of the above liver disease is closely associated with the concentration and composition of FAs. Our previous study found that phytosterol ester (PSE) could alleviate hepatic steatosis in nonalcoholic fatty liver disease rats. The aims of this work were to explore the effects of PSE (0.05/100 g·body weight) on FA profiles and the mRNA levels of FA metabolism-related genes. Compared with a high-fat diet alone group, PSE treatment significantly decreased hepatic saturated fatty acid levels (P < .05) and increased monounsaturated fatty acid (especially C16:1 n-7) levels in the liver, serum, and adipose tissue and polyunsaturated fatty acid levels in the serum and liver (P < .05) after 12 weeks of intervention. In particular, PSE treatment increased the level of C22:5 n-3, an FA that was negatively correlated with the degree of hepatic steatosis in the serum, liver, and adipose tissue. The increases in some unsaturated fatty acids are probably related to the upregulation of stearoyl-coenzyme A desaturase-1 and fatty acid desaturase-1.