Residual Synchronization Error Elimination in OFDM Baseband Receivers

Xingbo Hu,Yumei Huang,Zhiliang Hong 한국전자통신연구원 2007 ETRI Journal Vol.29 No.5

It is well known that an OFDM receiver is vulnerable to synchronization errors. Despite fine estimations used in the initial acquisition, there are still residual synchronization errors. Though these errors are very small, they severely degrade the bit error rate (BER) performance. In this paper, we propose a residual error elimination scheme for the digital OFDM baseband receiver aiming to improve the overall BER performance. Three improvements on existing schemes are made: a pilot-aided recursive algorithm for joint estimation of the residual carrier frequency and sampling time offsets; a delay-based timing error correction technique, which smoothly adjusts the incoming data stream without resampling disturbance; and a decision-directed channel gain update algorithm based on recursive least-squares criterion, which offers faster convergence and smaller error than the least-mean-squares algorithms. Simulation results show that the proposed scheme works well in the multipath channel, and its performance is close to that of an OFDM system with perfect synchronization parameters.

Fault Tolerant Strategy of Abnormal Battery Discharge

Guan Yu,Zhou Xingbo,Liu Peng,Zhao Yu 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.6

To solve the problem of abnormal battery discharge in the operation of electric vehicles, a method of fault tolerance based on data driven is proposed. First, based on the relation between transient voltage and the aging degree, battery SOC estimation model is built through LS-SVM method. Then, the fault-tolerant control scheme is put forward, which aims at abnormal discharge of power battery. When known battery exception occurs, the corresponding model control law is implemented to achieve fault tolerance control. When the unknown abnormal battery fault occurs, using dynamic data circulation way, the unknown exception model is rapidly established implementing system fault tolerant control for unknown exception. Finally, the accuracy of the method is verified by the simulation, which shows that this method is good for the fault tolerance of known and unknown faults.

Research on the Electric Vehicle Control System

Haiying Wang,Tianjun Sun,Xingbo Zhou,Qi Fan 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.8

With the development of electric vehicle electronic control unit (ECU) for vehicle control technology and the key to raise the level of design electric vehicles the optimization control of the vehicle performance as direction. In order to achieve the rational, coordination of vehicles within the system of integrated control, based on the modular thought, through constructing the distributed control network design overall structure of the control system of pure electric vehicle, the vehicle controller is analyzed on the working principle and its function realization degree, as a pure electric vehicle control system provides the theory basis for performance evaluation.

Damage Prediction of Hydraulic Concrete in Severe Cold Region Based on FOTP-GM (1,1) Model

Li Gong,Yuting Liang,Xingbo Yu,Ying Liang,Qiangye Du 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.7

In winter, hydraulic concrete is often under the synergistic destruction of the freeze-thawcycle, dry-wet alternation, and salt erosion. The special climate in cold and arid areas hasadverse effects on the safe operation and economic benefits of hydraulic buildings. Thedurability of polypropylene fiber-modified concrete under multiple working conditions wasstudied. Combined with the FOTP-GM (1,1) model, damage prediction of modified concreteunder different working conditions was carried out. The results show that a certain amount ofpolypropylene fiber significantly increased the corrosion resistance of specimens. The fittingdegree between the measured sequence and the model increased with increasing order ‘h’ ofthe time power term. Under different working conditions, the time power term correspondingto the optimal model structure was different. The correlation coefficient R2 between theestablished prediction model and the original sequence was above 0.9. Through erroranalysis, it was proved that the FOTP-GM (1,1) model can effectively predict the number ofcycles when the concrete reaches the failure standard. The optimal model structure can beused in practical engineering to establish a prediction model to calculate the safe 0service lifeof engineering structures.

Uniaxial Eccentric Load Behavior of L-CFSST Composite Column

Zhen Wang,Zhe Liu,Xingbo Wang,Xuejun Zhou,Zhoutai Wang,Guodong Xian 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.5

This study presents the mechanical behavior of L-shaped concrete-filled square steel tube (L-CFSST) composite columns under uniaxial eccentric compression. Nine specimens were tested and the effects of eccentricity, steel tube thickness, steel yield strength, and slenderness ratio were investigated regarding failure modes, ultimate load, load-lateral displacement curves, and load-strain curves. Test results showed that, under uniaxial eccentric load, these columns showed favorable mechanical properties and steel tubes showed strong cooperative working performance. There were two types of failure modes for these columns: local buckling of the steel tube or overall bending of the specimen. ABAQUS was used to simulate the loading process and the accuracy of the numerical simulation results was verified by comparing failure characteristics, load-displacement curves, and ultimate bearing capacity with the test results. The N/Nu-M/Mu curves of the columns under uniaxial eccentric load with different parameters were simulated by the finite element method. A simplified formula for predicting the N/Nu-M/Mu relationship was established based on the finite element analysis results, which might be a workable approach for designing L-CFSST composite columns in engineering practice.

Evaluating and predicting net energy value of wheat and wheat bran for broiler chickens

Ning Ran,Cheng Zichen,Liu Xingbo,Ban Zhibin,Guo Yuming,Nie Wei 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.11

Objective: It is crucial to accurately determine the net energy (NE) values of feed ingredients because the NE system is expected to be applied to the formulation of broilers feed. The NE values of 5 wheat and 5 wheat brans were determined in 12-to 14-day old Arbor Acres (AA) broilers with substitution method and indirect calorimetry method. Methods: A total of 12 diets, including 2 reference diets (REF) and 10 test diets (5 wheat diets and 5 wheat bran diets) containing 30% of test ingredients, were randomly fed to 864 male AA birds with 6 replicates of 12 birds per treatment. These birds were used to determine metabolizable energy (ME) (8 birds per replicate) in the chicken house and NE (4 birds per replicate) in the chamber respectively at the same time. After a 4-d dietary and environment adaptation period, growth performance, energy values, energy balance and energy utilization were measured during the following 3 d. Multiple linear regression analyses were further performed to generate prediction equations for NE values based on the chemical components and ME values. The NE prediction equation were also validated on another wheat diet and another wheat bran diet with high correlation (r = 0.98, r = 0.75). Results: The NE values of 5 wheat and 5 wheat bran samples are 9.34, 10.02, 10.27, 11.33, and 10.49 MJ/kg, and 5.37, 5.17, 4.87, 5.06, and 4.88 MJ/kg DM, respectively. The equation with the best fit were NE = 1.968AME–0.411×ADF–14.227 (for wheat) and NE = –0.382×CF –0.362×CP–0.244×ADF+20.870 (for wheat bran). Conclusion: The mean NE values of wheat and wheat bran are 10.29 and 5.07 MJ/kg DM in AA broilers. The NE values of ingredients could be predicted by their chemical composition and energy value with good fitness. Objective: It is crucial to accurately determine the net energy (NE) values of feed ingredients because the NE system is expected to be applied to the formulation of broilers feed. The NE values of 5 wheat and 5 wheat brans were determined in 12-to 14-day old Arbor Acres (AA) broilers with substitution method and indirect calorimetry method.Methods: A total of 12 diets, including 2 reference diets (REF) and 10 test diets (5 wheat diets and 5 wheat bran diets) containing 30% of test ingredients, were randomly fed to 864 male AA birds with 6 replicates of 12 birds per treatment. These birds were used to determine metabolizable energy (ME) (8 birds per replicate) in the chicken house and NE (4 birds per replicate) in the chamber respectively at the same time. After a 4-d dietary and environment adaptation period, growth performance, energy values, energy balance and energy utilization were measured during the following 3 d. Multiple linear regression analyses were further performed to generate prediction equations for NE values based on the chemical components and ME values. The NE prediction equation were also validated on another wheat diet and another wheat bran diet with high correlation (r = 0.98, r = 0.75).Results: The NE values of 5 wheat and 5 wheat bran samples are 9.34, 10.02, 10.27, 11.33, and 10.49 MJ/kg, and 5.37, 5.17, 4.87, 5.06, and 4.88 MJ/kg DM, respectively. The equation with the best fit were NE = 1.968AME–0.411×ADF–14.227 (for wheat) and NE = –0.382×CF–0.362×CP–0.244×ADF+20.870 (for wheat bran).Conclusion: The mean NE values of wheat and wheat bran are 10.29 and 5.07 MJ/kg DM in AA broilers. The NE values of ingredients could be predicted by their chemical composition and energy value with good fitness.

Association of Single Nucleotide Polymorphisms in Exon 6 Region of BMPRIB Gene with Litter Size Traits in Sheep

Jia, Cunling,Li, Ning,Zhao, Xingbo,Zhu, Xiaoping,Jia, Zhihai Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.10

The objective of this study was to investigate polymorphisms of BMPRIB (bone morphogenetic protein type IB receptor) gene and its effect on litter size traits in sheep. Three populations including 101 Small Tailed Han sheep, 79 Poll Dorset and 81 hybrids (Poll Dorset${\times}$Small Tailed Han sheep) were used to detect the polymorphisms in exon 6 region of sheep BMPRIB gene. A fragment of approximately 190bp was amplified by one pair of primers, the polymorphism was revealed from the analysis of three populations by the technique of PCR -SSCP, and a mutation from A to G at 746 of the coding region was confirmed by sequencing in several individual. Statistical results indicated the distribution of allele B (with a A$\longrightarrow$G mutation) and A (without mutation) or genotype AA, AB and BB frequencies differed in three populations. BB genotype (44.55%) and B allele (66.34%) frequencies of Small Tailed Han sheep were higher than those of the others. Analysis of variance showed that the polymorphism of BMPRIB gene was associated with positive effect on litter size traits. The means of genotype BB and AB were about 1.04 and 0.74 more than genotype AA for litter size (p<0.05). Analysis of BMPRIB genotype effects on litter size in three populations indicates the existence of genotype BB or B allele increases the litter size. It suggested that the polymorphism in exon 6 (at 746 in the coding region) of sheep BMPRIB gene may be used as a marker for early selection of prolificacy in sheep.

Effect of Urolithin A on Bone Repair in Mice with Bone Defects

Liu Jianmin,Ma Longyang,Dong Wengang,Du Gongliang,Dang Xingbo 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.1

BACKGROUND: Bone defect difficult to manage clinically and it is a big challenge to repair it. Secondary metabolites source from herb has shown potential for the treatment of bone defect. METHODS: Mesenchymal stem cells (MSCs) were isolated from mice and incubated with urolithin A (UA) (10, 25, and 50 lg/mL). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was performed to estimate apoptosis and mineralisation was evaluated by alkaline phosphatase assay and alizarin red S staining. A middle femoral defect was induced in mice and bone tissue was prepared for endochondral ossification by treating with UA. The effect of UA was estimated by determining markers of osteoblast proliferation in serum and micro-computed tomography to analyse bone defects. RESULTS: UA enhanced mineralisation of MSCs and osteogenic gene markers in MSCs in vitro. Also, the bone defect score and bone mineral density were improved by UA. Moreover, UA ameliorated the altered Wnt3a protein and histopathological changes in bone defect mice. CONCLUSION: Presented report conclude that UA enhances osteoblast proliferation in bone-defect mice by activating the Wnt pathway.

Analysis of Face Stability Based on Incomplete Soil Arching Effect

Fei Ye,Chang Liu,Xiaoming Liang,Aohui Ouyang,Ping Lei,Xingbo Han 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.4

The excavation face stability is a critical issue in the analysis of the tunneling disturbance to the surrounding environment, in which the soil arching effect is a phenomenon that cannot be ignored. Based on the wedge-prism model, this study proposed a slice method to calculate the limit support pressure, taking into account both the vertical soil arching effect of the prism and the horizontal arching effect of the wedge. In addition, the rotation of the principal stress was introduced to improve the lateral stress ratio on the vertical sliding faces including the wedge and the prism, in which two new trajectories of the major principal stress were recommended, based on a previous numerical study. Furthermore, the contribution of the incomplete soil arching effect was discussed in this study, assuming that there was a function between the effective internal friction angle of the soil and the tunnel cover depth. Through the comparison of the results with theoretical and numerical models, the improved model was validated and showed agreement with them. Finally, parameters related to the limit support pressure were thoroughly investigated to provide a better understanding of the proposed model.