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The current fusion-based methods transform LiDAR data into bird’s eye view (BEV) representations or 3D voxel, leading to information loss and heavy computation cost of 3D convolution. In contrast, we directly consume raw point clouds and perform fusion between two modalities. We employ the concept of region proposal network to generate proposals from two streams, respectively. In order to make two sensors compensate the weakness of each other, we utilize the calibration parameters to project proposals from one stream onto the other. With the proposed multi-scale feature aggregation module, we are able to combine the extracted regionof-interest-level (RoI-level) features of RGB stream from different receptive fields, resulting in fertilizing feature richness. Experiments on KITTI dataset show that our proposed network outperforms other fusion-based methods with meaningful improvements as compared to 3D object detection methods under challenging setting.

Due to the serious impact of border control measures during the ongoing novel coronavirus (COVID-19) epidemic, new difficulties and challenges have been brought to the border lines of most countries and regions. Focusing on the post-COVID global economic recovery, we develop a computing method for studying the health inspection process based on a three-color risk screening management mechanism at border crossing checkpoints. In this article, to manage the cross-border risk efficiently during the epidemic prevention and control, we formulate a queueing model with hierarchical health inspection channels. The structural characteristics and properties of this three-level queueing model are also analyzed by studying the health inspection process with risk classification. Furthermore, we conduct a series of sensitivity analysis on several performance measures for the studied queueing system. In the numerical results, we figure out the monotonicity, convexity and complicated patterns of the derived formulas.

In the past decades, with the increase of universities enrollment in China, how to relieve the pressure of the employment of college graduates has become a hot issue for the whole society. Since then, entrepreneurship education has been adopted and popularized by more and more colleges and universities. However, there is not a very unified understanding of the definition and the way in which entrepreneurship education is carried out. Bases on the current employment situation and the development of entrepreneurship education in colleges and universities in China, this paper proposes some rational thinking on the development of university students' entrepreneurship education in China and reiterates the connotation and implementation of entrepreneurship education.

Colorectal cancer (CRC) ranks as the third-leading cause of cancer-associated mortalities in Taiwan. The expression of ribonucleotide reductase M2 (RRM2) and p53R2 is associated with tumoral malignancy and progression in several types of cancer. The aim of the present study was to determine the association of p53R2/RRM2 with the upstream expression of microRNA (miR)-211 and the association of expression levels of p53, APC and k-ras with clinical outcomes in patients with CRC. The study consisted of 192 tumor tissue samples obtained from patients with CRC. Immunohistochemistry and direct sequencing of DNA were performed to analyze p53R2/RRM2 protein expression and p53/APC/k-ras gene mutations in these samples. The expression level of miR-211 was detected by reverse transcription-quantitative polymerase chain reaction. The results showed that the expression of p53R2 was lower and that of RRM2 was higher in patients with lymph node metastasis, distant metastasis, and late-stage CRC compared with patients without lymph node metastasis, distant metastasis and early-stage CRC. A high expression of RRM2 in patients had a negative effect on overall survival (OS) and disease-free survival (DFS) in CRC. Positive expression of RRM2 was detected in tumor tissues, and expression associated with the presence of k-ras gene mutation. Furthermore, it was detected that the upstream miR-211 expression was negatively associated with RRM2 expression in tumor tissues of patients with CRC. miR-211 expression was associated with survival and tumoral recurrence in patients with k-ras mutations. The present authors suggest that the downregulation of miR-211 and overexpression of RRM2 in tumor tissues of patients with CRC could be used to predict metastases and disease prognosis, particularly in patients with k-ras gene mutations.

This paper proposes a method using non-linear voltage-current characteristics for multiple harmonic sources classification using wavelet hybrid neural network (WHNN). Typical voltage-current characteristics of harmonic sources are non-linear closed curves in the time-domain, referring to the converters, reactors, and non-linear loads. The hybrid neural network is a two-subnetwork architecture, consisting of wavelet layer and a self-organizing feature map (SOFM) network connected in cascade. The effectiveness of the proposed method is demonstrated by numerical tests. The results of multiple harmonic sources show the computational efficiency and accurate classification.

In this paper, we develop an Arena simulation model to study the optimal design of security-check systems for screening passengers in airports. With the increasing of terrorist attacks, the airport safety has become more and more important, but the enhanced security increases transportation costs and reduces airport efficiency. Through the numerical experiments with our Arena simulation models, it demonstrates the effects of the risk threshold for further inspection on the passengers’ average waiting time and the airport’s safety level.

This study proposes a novel light-emitting diode (LED) driver circuit that stabilizes the lighting output without a photodiode. The LED driver circuit is composed of a self-alignment circuit to compensate for the photo-power deviation and a feedback control system instead of a conventional photodetector to maintain the electrical power of the LED. The LED characteristics, based on electrical and optical measurements that varied with temperature, were built to be a lookup reference of the generated LED photopower, which serves as a compensator. A commercial full color LED system, which comprises red, green, and blue (RGB) LED chips, was implemented according to the novel concept. The impact of a conventional current regulator, a proposed electrical-power stabilization circuit, and a self-aligned photo-power stabilization circuit was studied graphically, followed by experimental verification. The maximal and minimal rate of change of the radiant flux Φ driven by the proposed LED drivers are 3.467% in a red LED, and 2.848% in green LED, respectively, over the ambient temperature range of 0.5-85 °C. The experimental results verified the implementation of a lighting power stabilization control system without the use of a photodiode for RGB LEDs.

Kaohsiung and Pintung are the first regions were set into action of total quantity control zones for air quality in Taiwan. Cap and trade programs have built for the particle matters (PM10), sulfur oxides (SOx), nitrogen oxides (NOx) and Volatile Organic Compounds (VOCs) in 2010. The offset ratio was designed as 1.0 or 1.2 various on the offset sources. The fixed offset ratio setting is suitable for PM10, SOx, and NOx since their characters are unitary. However, VOCs include a variety of chemicals, some of which may have short- or long-term adverse health effects. Even the same pollutant trading amount cannot guarantee the same health risk or environmental impacts. It would induced the highly uncertainty of air quality for the fixed offset ratio system. This study therefore tried to create a new methodology based on the pollutant impact strength of health and environment for determining the offset ratio of VOCs. An equation for calculating the offset ratio of VOCs was proposed and evaluated by case study. The elasticity of weighting determination was remained to the decision makers for confronting the various environmental improving targets.

This paper introduces two revenue management schemes to allocate the limited bandwidth from capitalistic and socialistic perspectives, respectively. Under the budget constraint, the revenue functions with the congestion costs are studied through the mathematical properties of the blocking probability with respect to the bandwidth allocation. In addition, we derive the monotone and convex relations between the allocated bandwidth and factors affecting the revenue functions. The analysis for the proposed two management schemes contributes managerial insights for different network managers while determining bandwidth allocation on their operating network.

In this paper, we study an extension of atomic routing games for multi-class communication networks with quality of service requirements, which can be formulated as a network management scheme. Atomic routing games are non-cooperative games with multiple selfish players, where each player has to choose a path in a given graph to route his traffic, and then pays the corresponding cost. We develop a mixed-integer nonlinear programming model for the network management scheme in this class-based communication network. The analysis of this work offers appropriate resource allocation and a routing database identifying suitable end-to-end paths upon each connection request.

This paper takes advantage of digital dimming auto-control pulse width drive Light-Emitting Diodes to let the light in terms of brightness fade to gray by degrees and have the effect of mixture of colors. Also, Light-Emitting Diodes in such three primary colors as red, green, and blue mix with one another to yield various colors. Therefore, better stability, simpler structure and better effect of dimming. Moreover, it succeeds in utilizing red, green, and blue Light-Emitting diodes at room temperature to change Color Rendering Index of the cool white Light-Emitting Diodes. The design of the circuit makes use of the manufacturing technique of Very Large Scale Integration to make the completion of Integrated Circuit (TSMC 0.35μm MIXED MODE 2P4M 3.3v process).

The brightness of a Light Emitting Diode is proportional to the forward current. Constant LED forward current provides brightness. Temperature is an important factor in LED color temperature. The color temperature varies when the temperature varies. Therefore, an advanced temperature control scheme is proposed. An Automatic Color Temperature Control Circuit with color temperature compensation is proposed. It is confirmed that the proposed system provides stable color temperature within a temperature range from -30℃ to 85℃.

LED is one of the best energy efficient components. As a light source, LED presents advantages as lower power consumption, higher brightness and longer lifetime. This paper presents an in-depth description of applying power line communication technology to LED lighting system. By using power lines as communication media to transfer control data, LED is controlled by existing lines on the power system. In this research, we use the LED which contains RGB tricolor in its package, so the change of color dimming can be controlled by a PWM controller.

We design a digital automatic power control system based on an automatic current control circuit (ACC) because an automatic current control circuit has the advantage that it doesn't require a photodiode to sense light intensity and correct output current, and we can adjust the current flowing through a light-emitting diode when the voltages of light-emitting diodes vary with temperature. Reducing the dependence of LED light power on temperature is our main goal. The digital automatic power control system in this paper includes an instrumentation amplifier, a microprocessor, a digital-to-analog convertor and a voltage-to-current circuit.

With the emerging popularity of multimedia applications, quality of service on Internet becomes an important issue. Random Early Detection (RED) is one of the most widely used adaptive queue management in the Internet. In this paper, we extend the basic concept and study an analytic model for RED queues with batch arrival and multiple servers. A Markovian approach is presented in order to study different quality metrics by RED parameters, such as batch sizes, dropping rates, etc. Numerical results obtained by simulation and analytic methods illustrate those performance measures of the proposed RED queue, such as average system/queue sizes, average sysetm/queue waiting time, average dropping probability.

The drawback in using the light emitting diode as a light source is that its light output power is highly temperature dependent. This paper puts forth the novel idea of neglecting the photo diode as a luminance sensor and taking advantage of pulse-width modulation at the same time. A light emitting diode power controller based on automatic power control technology is introduced. The controller can reduce the power dependence of the electrical component on temperature and regulate light emitting diode brightness according to the pulse-width modulation. In this way, the current flowing through the electrical component can be switched off to reduce the power consumption and to prevent electrical component over heating. Finally, the comparisons between voltage source with ballast resistor, automatic current control and proposed photo-power control are discussed in this paper. All these three compensated mechanisms are without photodiode. The experimental results show the proposed method is effective in providing constant luminous intensity.

This paper proposes a color mixing control system that provides adjustable color mixing using pulse-modulation light brightness period control while driving red-green-blue (RGB) light-emitting diodes (LED). The proposed control system includes a clock unit that provides a first clock signal and a second clock signal with a frequency lower than that of the first clock signal. Three control units are coupled to three LEDs emitting three different colors, respectively. Each control unit is operated based on the clock signals and a corresponding set of first and second reference values output to a driving pulse signal to the corresponding LED. Using four bit digital signal control, 4096 different colors and 16 gray levels can be provided by the digital pulse width modulator (DPWM) system. The system works using a single 5V power supply with a maximum clock frequency of 1MHz.

A feedback power control system includes: a multiplying unit receiving work voltage corresponding to the voltage drop in an electrical component and feedback voltage corresponding to the work current flowing through the electrical component, with outputting a measurement voltage corresponding to the power consumed by the electrical component, having a value equal to the product of the work voltage and feedback voltage. The control unit receives the measurement voltage from the multiplying unit and a reference voltage, and outputs a control voltage corresponding to the difference in voltage between the measurement voltage and the reference voltage. The regulating unit provides the feedback voltage to the multiplying unit and includes an amplifier that receives the feedback voltage from the electrical component. In this way, we can adjust the current flowing through the electrical component when the electrical component voltages vary with temperature. Reducing the power dependence of the electrical component to the temperature that compensates the temperature is our purpose. Both the automatic constant current and automatic power control can be provided by a single system.

The Peer-to-Peer (P2P) approaches utilize the passive means of delivering large amounts of content due to the ease of content delivery and small amount of effort required for file transmission and failure control by the file provider. However, P2P methods incur network congestion due to the large number of uncontrolled connections established by those retrieving content. Additionally, P2P methods potentially stop file providers from exchanging data with other devices because of congested outbound traffic. Therefore, existing P2P approaches are infeasible for large-scale organizations as a congested uncontrolled network is not ideal in a business environment. Related studies demonstrated that the active method for content can minimize outbound congestion for a provider but it needs the fault tolerance. This study presents a novel application called Enterprise Peer-to-Peer (EP2P), which integrates passive and active approaches. Using EP2P, the outbound traffic from a sender on an Intranet can be controlled efficiently, because the transmission between a provider and many receivers can be changed from passive to active on necessary. Therefore, we suggest organizations use EP2P for the delivery of content.

We propose a mathematical model for calculating blocking probabilities with optimal bandwidth allocation and QoS routing on multiclass communication networks. This scheme is performed by means of a two-phase procedure. The first step determines optimal paths under network constraints. The second step computes the blocking probability with predetermined optimal solutions. The blocking is due to the failure of meeting the demand of end-to-end paths for each class.

We present an integer programming approach to offer optimal bandwidth allocation and QoS routing for network management problems with heterogeneous service classes. The bandwidth allocation policy in such communication networks is determined in accordance with the proportionally fair rule, which can be expressed by utility functions of network users. The objective of this utility maximization scheme is to prepare a routing table for future user request. This routing table identifies the allocated bandwidth and the suitable end-to-end path under QoS guarantees for each user. We analyze the mathematical properties of the optimal bandwidth allocation and provide computational results to demonstrate the validity and efficiency of the proposed scheme.

We propose a precomputation-based scheme which offers Pareto optimal solutions to the network dimensioning problem. This scheme is performed by means of a two-phase procedure. The first phase precomputes paths for a wide range of possible constraints, while the second phase selects an adequate path through a simple procedure. That is, the first phase prepares a routing database which enables to identify a suitable path upon each connection request through the second phase. We propose a bandwidth allocation model with nonlinear utility functions. We focus on allocating resources with proportional fairness and finding a routing scheme on communication networks.

Downward communication is a popular push-based scheme to forward messages from headquarters to front-line staff in a large-scaled company. With the maturing intranet and web technology, broadcasting algorithms, including pull-based and push-based broadcasting algorithms, it is feasible to send downward messages through web-based design by sending packets on a network. To avoid losing messages due to the traditional push-based method, companies adopt a pull-based algorithm to build up the broadcasting system. However, although the pull-based method can ensure that a message is received, it has a critical problem, the network is always congested. The push-based method can avoid congesting the network, but it needs a specific robust design to ensure that the message reaches its destination. Hence, adopting only a pull-based or a push-based broadcasting algorithm is no longer feasible especially not for a large-scaled company with complex network architecture. To ensure that every receiver will read downward messages thereby reducing the consumption of network bandwidth, this work proposes a robust web-based push- and pull-based broadcasting system for sending downward messages. This proposed system was successfully applied to a large-scaled company for a one-year period.

This paper considers the problem of bandwidth allocation on communication networks with multiple classes of traffic, where bandwidth is determined under the budget constraint. Due to the limited budget, there is a risk that the network service providers can not assert a 100% guaranteed availability for the stochastic traffic demand at all times. We derive the blocking probabilities of connections as a function of bandwidth, traffic demand and the available number of virtual paths based on the Erlang loss formula for all service classes. A revenue/profit function is studied through the monotonicity and convexity of the blocking probability and expected path occupancy. We present the optimality conditions and develop a solution algorithm for optimal bandwidth of revenue management schemes. The sensitivity analysis and three economic elasticity notions are also proposed to investigate the marginal revenue for a given traffic class by changing bandwidth, traffic demand and the number of virtual paths, respectively. By analysis of those monotone and convex properties, it significantly facilitates the operational process in the efficient design and provision of a core network under the budget constraint.