Partitioning Clustering Based on Support Vector Ranking

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Historical Development of the Undergraduate Educational Model at BIT from the Perspective of Suzhi Education

From the perspective of suzhi education, this study analyses the historical development of the undergraduate educational model at Beijing Institute of Technology (BIT). It could be argued that BIT’s talent-cultivating system’s transformations from 1940 to 2020 echo Chinese higher education’s reform and development. This study concludes that BIT has experienced four phases: (1) from advocacy for general-specialized education’s integration to general education’s disappearance, (2) from the rectification of specialized education to the germination of suzhi and general education, (3) the flourishing of suzhi education and general education, and (4) the establishment of the Shuyuan System. The case of BIT reflects Chinese higher education’s development and the process of transforming from meritocracy to popularization. Chinese universities have changed their paradigm from emphasizing specialized education to highlighting suzhi education, as well as from focusing on training students into specialists to stressing students’ holistic development

DORT: Modeling Dynamic Objects in Recurrent for Multi-Camera 3D Object Detection and Tracking

Recent multi-camera 3D object detectors usually leverage temporal information to construct multi-view stereo that alleviates the ill-posed depth estimation. However, they typically assume all the objects are static and directly aggregate features across frames. This work begins with a theoretical and empirical analysis to reveal that ignoring the motion of moving objects can result in serious localization bias. Therefore, we propose to model Dynamic Objects in RecurrenT (DORT) to tackle this problem. In contrast to previous global Bird-Eye-View (BEV) methods, DORT extracts object-wise local volumes for motion estimation that also alleviates the heavy computational burden. By iteratively refining the estimated object motion and location, the preceding features can be precisely aggregated to the current frame to mitigate the aforementioned adverse effects. The simple framework has two significant appealing properties. It is flexible and practical that can be plugged into most camera-based 3D object detectors. As there are predictions of object motion in the loop, it can easily track objects across frames according to their nearest center distances. Without bells and whistles, DORT outperforms all the previous methods on the nuScenes detection and tracking benchmarks with 62.5\% NDS and 57.6\% AMOTA, respectively. The source code will be released

Investigation on dynamic characteristics of mechanical assembly

Mechanical assembly is important process affecting product dynamic quality. To completely inspect assembly quality, dynamic characteristic analysis is necessary. Based on substructuring dynamic analysis, this paper theoretically analyzes the changes of dynamic characteristics due to assembling process. Assembly coupling dynamic stiffness computed by inverse substructuring analysis is considered as a critical measure on the changes. The results obtained have been well validated by a lumped-parameter model for two-level of substructures

Eigenvalue analysis and estimation on dynamic quality of mechanical assembly

As an important manufacturing process, mechanical assembly affects directly product quality. Conventional quality inspections and estimations of mechanical assembly are primarily concentrated in “static quality”, such as size coordination, shaping and positioning tolerances, etc. However, mechanical assembly actually has its own dynamic quality, which contributes to that of whole product. Inspecting only static quality is thus incomplete for quality estimation of the assembly. On the basis of substructuring method, this paper at first applies eigenvalue analysis to investigate the effects of assembling process on the dynamic transfer-functions, expressed by spectral-based frequency response functions (FRFs), of substructural components involved in the process. Eigenvalue modules of FRF-matrix-ratios of FRF before assembling to that after assembling are analyzed to quantify the effects, which are consequently indicated by the mean module. Then, according to the explicit definition of “dynamic quality of mechanical assembly” introduced in this paper, dynamic quality matrix of mechanical assembly and its mean eigenvalue module are worked out and chosen to be the right quantitative measure and indicator for dynamic quality estimation of assembly system. Meanwhile, a lumped-parameter model and its experimental counterpart are employed to validate effectiveness of the analytical outcomes obtained and the quality estimation method established in the study

Empirical Study on Consumer Perceived On-line Payment Risk

This paper takes the potential release of online transaction market size as the starting point of research, and discusses how Chinese consumer perceived risks influence online payment willingness. This study divides consumer perceived risks of online payment into eight dimensions: Economic risk, Functional risk, Private risk, Security risk, Time risk, Service risk, Psychological risk and Social risk. Furthermore, it explores the influence of multi-dimensional perceived risks on the willingness of consumers’ online payment on the basis of 616 samples from Shanghai. The empirical results show that there is a significant negative correlation between perceived economic risks and the willingness to pay online; perceived security risks and some other risks have significant positive effect on payment willingness, which shows that certain perceived risks are becoming systemic risks in accordance with the principle of finance. So, the paper imply that both Private and Government third payment platforms shall take certain measures to reduce consumers’ specific perceived risk for promoting the development of online transaction market in China

Distinct different expression of Th17 and Th9 cells in coxsackie virus B3-induced mice viral myocarditis

<p>Abstract</p> <p>Background</p> <p>Recently, a new subset of CD4⁺T helper(Th) cell that predominantly secret cytokine interleukin-9(IL-9) is identified, termed Th9 cell. It has been reported to participate in tissue inflammation and autoimmune responses, and induce disease which differed from Th17 cells. Th17 cells have been shown to play a critical role in viral myocarditis (VMC), but whether Th9 cells are involved in the pathogenesis of VMC remains unclear.</p> <p>Results</p> <p>BALB/c mice were intraperitoneally (i.p) injected with coxsackie virus B3(CVB3) for establishing VMC models. Control mice were treated with phosphate-buffered saline i.p. On day 0,7,14,21,28,35,42 after injection, myocardial histopathological changes were evaluated by hematoxylin-eosin staining. Splenic Th17 and Th9 cells subsets were analyzed by flow cytometry. And cardiac IL-17, IL-9 mRNA were measured by semi-quantitative reverse transcription-PCR and nested PCR, respectively. Results showed the levels of Th17 cells and IL-17 mRNA obviously increased in VMC mice on 7 day after infection, peaked on day 28, and highly persisted to at least day 42 (p < 0.05). While the frequencies of Th9 cells and IL-9 mRNA showed no significant difference between VMC and control group throughout the course of the experiment(p > 0.05).</p> <p>Conclusions</p> <p>It was differentiated Th17 but not Th9 cells significantly elevated in the development of CVB3-induced VMC. The microenvironment of VMC seemed to contribute to the differentiation and proliferation of Th17 rather than Th9 cells. Our preliminary data implied Th9 cells could not protect against VMC nor promote the disease.</p