A low latency high throughput Dynamic Virtual Output Queues Router for On-Chip interconnect networks is proposed in this paper, which can reduce the router latency to two cycles by leveraging look-ahead routing computation and virtual output queues scheme. Compared to wormhole router and virtual channel router, Simulation results show that network throughput on a 4×4 mesh increases by up to 46.9% and 28.6% respectively, and outperforms doubled buffer virtual channel by 1.9% under same input speedup. Network zero-load-latency also decreases by 25.6% and 41% respectively under random traffic. Synthesis results in TSMC 65nm technology indicate the frequency of router with 0.404mm2 area can reach 2.5 GHz.

随着高速信道的传输速率变快,传输长度变长,结构复杂度变高,对信道进行建模也变得复杂与艰难.将目前比较火热的机器学习方法与高速信道结合起来,提出了一个新颖的方法.利用采集的大量模拟数据,采用深度神经网络DN N与循环神经网络RN N对信道建模,模型一旦训练成功,就可以通过该仿真模型预测输出信号的眼图,快速精准地对信号完整性进行评估和分析.另外,在高速信道中,信号的严重干扰和衰减问题会限制传输距离和传输速率,给测试和信息采集带来困难.为了恢复理想信号,高速串行链路通常包含复杂的均衡摸块,采用最小均方算法LMS可以有效地消除干扰,减小误码率,提高传输速率.

Iron-rich red mud is a potent radioactive drainage treatment material. However, the calcite in red mud attenuates its U adsorption capacity by restricting U adsorption onto adsorbent; it captures U as a dissociative complex in aqueous systems. This study produced macroporous iron and carbon combined calcined red mud (ICRM) and carbon calcined red mud (CRM) through calcination in the range of 500-800 degrees C. XRD results revealed that both series generated advantageous magnetite and calcite were fully decomposed. SEM and batch experiments highlighted ICRM calcined at 600 degrees C has more stable and favorable performance. The components of post-adsorption ICRM remained active, as demonstrated by FT-IR results. Additionally, ICRM@600 displayed superior U adsorption capacity (59.45 mg/g) than did all red mud adsorbents from our previous research. Zeta-potential results revealed ICRM has positive potential charges in acidic conditions, indicating it adsorbs U(VI) ions via electrostatic attraction. The main adsorption mechanisms of ICRM are surface electrostatic attraction, physical adsorption by porous structure, and chemical adsorption by active Al and Fe components. In application, ICRM@600 obtained a 82.20% U adsorption ratio in uranium mine pit drainage. Overall, this study offers theoretical guidances to radioactive drainage management and red mud reuse.

Facing the challenges of the next generation exascale computing, National University of Defense Technology has developed a prototype system to explore opportunities, solutions, and limits toward the next generation Tianhe system. This paper briefly introduces the prototype system, which is deployed at the National Supercomputer Center in Tianjin and has a theoretical peak performance of 3.15 Pflops. A total of 512 compute nodes are found where each node has three proprietary CPUs called Matrix-2000+. The system memory is 98.3 TB, and the storage is 1.4 PB in total.

遥感图像分析在国土资源管理、海洋监测等领域有着极为广阔的应用前景.深度学习技术已在图像处理领域取得突破性进展,然而,遥感图像固有的尺寸大、目标小而密集等特点,使得将面向普通图像的深度学习方法用于遥感目标检测普遍存在定位不准确、小目标检测难、大图检测精度差等问题.针对上述难题,提出了一种新型遥感图像目标检测算法DFS.与传统机器学习方法相比,DFS设计了新的维度聚类模块、定制损失函数和滑动窗口分割检测机制.其中,维度聚类模块通过设计聚类机制优化定制先验框,提高定位精度;定制损失函数提高对船只等小目标的检测精度;滑动窗口分割检测解决大图检测精度低的问题.在经典遥感数据集上开展的实验对比表明,与YOLOv2相比,DFS算法的mAP提高了25.6％,小目标检测效率及大图检测效能大幅提高.

The side-channel attacks (SCAs) use the correlation between the power leakage information and the key to implement the attack process. The result of SCAs has a certain probability. If guessing an 8-bit key, there is a probability of 1/256 that the key will be guessed coincidentally, resulting in false positive. Therefore, the reliability of result key also needs an index to measure. Thereby, this paper proposes a novel evaluation index based on confidence value (CV). The CV of result key is divided three levels, low false positive, medium false positive and high false positive. CV provides a new reference index for the designers, suppliers and users of cryptographic devices to evaluate the security of devices.

Battery SOC is affected by many uncertain factors, so it is difficult to predict the exact value. In view of this situation, a convolution neural network prediction method optimized by genetic algorithm is proposed. Taking voltage_measured, current_measured, temperature_measured, current_load and voltage_load as input vectors of the neural network, genetic algorithm is used to generate the initial weights of neural network, and the GA-CNN battery SOC prediction model is constructed. The software and hardware GA-CNN neural network is realized by C language and FPGA programming respectively. The software implementation verifies the correctness of the algorithm, and the hardware implementation achieves the effect of real-time monitoring. The experiment results of C language show that the battery SOC prediction results based on GA-CNN neural network are more accurate. The hardware simulation results are consistent with the software results.

Uranium is a hazardous and radioactive element. Effective removal of uranium from wastewater stream requires advanced functional materials and reliable technologies. Red mud is a type of low-cost adsorbent which is widely used in the adsorption process. In the present work, we successfully modified the raw red mud to gain a series of highly efficient sorbents for uranium removal. They are nitric acid dealkalized red mud (DRM), aluminum nitrate modified red mud (ARM), and ferric nitrate modified red mud (FRM). The adsorption efficiencies of uranium(VI) by DRM, ARM, and FRM were 74.50, 95.56, and 98.75% in their optimal immobilization regions, respectively. The chemisorption of uranium dominates the adsorption process of FRM, while as to physical adsorption dominates the adsorption process of ARM and DRM. Both DRM and ARM reached their maximum adsorption capacities at 10 min while that for FRM occurred at 30 min. FRM performed much stronger anti-interference ability to the influence of carbonate and calcium. The outstanding adsorption ability of these modified red muds is mainly due to the enhancement of ion exchange, co-precipitation, and electrostatic attraction by red mud’s active components and functional groups.

High-performance computing (HPC) is essential for both traditional and emerging scientific fields, enabling scientific activities to make progress. With the development of high-performance computing, it is foreseeable that exascale computing will be put into practice around 2020. As Moore’s law approaches its limit, high-performance computing will face severe challenges when moving from exascale to zettascale, making the next 10 years after 2020 a vital period to develop key HPC techniques. In this study, we discuss the challenges of enabling zettascale computing with respect to both hardware and software. We then present a perspective of future HPC technology evolution and revolution, leading to our main recommendations in support of zettascale computing in the coming future.

A low temperature coefficient (TC) CMOS voltage reference generator suitable for low temperature is proposed. It exploits temperature mutual compensation relationship between threshold voltage and thermal voltage, and provides a mean reference voltage of 692 mV. A proportional to absolute temperature (PTAT) current containing the thermal voltage which has a positive TC is generated, and then it is injected into a diode-connected NMOS transistor that supply the threshold voltage which has a negative TC. The mixing of the two voltages produces a reference voltage with zero TC. The proposed circuit is implemented with SMIC CMOS 0.18 um process technology. The simulation results show that the power consumption is 2.1 uW and the TC is 9.3 ppm/°C. The temperature range is from −75°C to 65°C, which indicates that the proposed circuit can be applied in low temperature environment.

Dynamic circuits are widely used in high-speed circuit. However, dynamic circuits are very vulnerable to soft errors. An analytical model of critical charge for vulnerable nodes of dynamic circuits is developed. As the accurate model is too complex to calculate, a simplified efficient model is proposed by using an approximate method. Proposed model are verified by SPICE simulation and error analysis respectively. Results demonstrate that these models have high accuracy and can be used both in the efficient analysis and automatic CAD tools.

Electronic equipment system is always manufactured as a super precision system. However, it will be used in harsh environment. For example, the computer in moving carriers will acted by vibrations. The objective of this paper is to provide a systematic investigation to computer-aided design of the vibration isolator for protection of electronic equipment in harsh vibration environment. This papers deal with fast solving method of natural frequency and system response of six DOF (Degree of Freedom) vibration isolator system. In the foundation of a mathematical model of vibration motion differential equation, the state space method is derived and presented. Through transforming the vibration isolation differential equations into the state space equations, it is convenient to facilitate the solution of vibration isolation coefficient of vibration isolation system of six DOF of freedom, by using the state space method and the MATLAB/Simulink model. Comparisons with reality data, Simulation results showed the result is consistent with the reality result. The state space method can find further applications on the selection of vibration isolation system and the evaluation of vibration isolation efficiency.

由于高速光开关在光互连通信中越来越广泛的应用,光开关的开关速度直接影响了整个光链路的传输速率,因此对驱动光开关产生长周期窄脉冲光信号的驱动电路的性能及集成度有了更高要求。基于光电集成工艺和高速光脉冲队列技术的发展,提出了一种应用于光SerDes收发器的集成ps级窄脉冲光信号产生器。该产生器为CMOS电路产生脉宽精确可调的长周期窄脉冲,在SMIC 0.13μm CMOS工艺下可获得窄至25ps的脉冲输出,其电源电压范围宽达1.4V~2.5V,时钟频率也可由数kHz到4GHz,同时可移植到不同的CMOS工艺平台。

The paper presents a high power supply rejection ratio (PSRR) CMOS bandgap reference (BGR). The circuit adopts a pre-regulator. To facilitate comparison, BGRs with- and without-pre-regulator are, respectively, designed and simulated in the 0.13 mu m standard CMOS process technology. Simulation results show that the PSRR of the designed BGR with pre-regulator achieves, respectively, -107.3 dB, -106.6 dB and -75 dB at 100 Hz, 1 kHz and 100 kHz, while PSRR of BGR without pre-regulator has only, respectively, -70.6 dB, -70.5 dB and -65 dB at 100 Hz, 1 kHz and 100 kHz. The BGR with pre-regulator achieves a bandgap voltage reference of 0.76 V, a temperature coefficient of 0.55 ppm/degrees C in the temperature range from -25 degrees C to 125 degrees C, and a deviation of output voltage of 0.08 mV when the power supply voltage changed from 2.6 V to 6.2 V.

提出一种基于二进制加权电容DAC阵列的比较器校准技术,并基于该技术65nm CMOS工艺下设计实现了一款低功耗高精度动态比较器。基于版图数据的模拟仿真结果表明,在1.2V的工作电压下,该校准技术可以将失调电压降低至0.25mV以下,功耗为0.33μW,功耗开销增大57%。

Solid waste, such as sulfide tailings, is exposed to oxidizing environment. And the acid mine wastewater generated by solid waste in the weathering is the main cause for the surrounding mining ecological environment pollution. Current domestic and foreign research work has mainly focused on the release of heavy metals in the oxidation environment. The release of heavy metals in the anoxic environment, however, is less paid attention to the environmental behavior of sulfide tailings and the potential risk of metal pollution. A water seal device of pyrite tailings leaching is designed in this work to investigate the variation of anoxic condition in different depth of leachate conductivity, dissolved oxygen, redox potential, pH and the release ability of metal such as thallium (Tl). Our results show that this method can make the water treatment system in a hypoxic environment, and inhibit the oxidation of pyrite tailings to produce acid emissions, so that the system of the reduction state in neutral is maintained. The migration behavior of different metals under the condition of water seal has opposite trend, namely, the migration activity of Tl, Pb, Cr, Al, Fe in the tailings is suppressed effectively, and reduce its emissions with the reduction of dissolved oxygen. The migration activity of Mn, As, Ni, Cu, Rb, and Sr is increased with decrease of dissolved oxygen, while, the migration activity of Mn and As is increased more obviously with the increasing of the release concentration. Heavy metals of Cu, Rb, Ni, Sr are released into the aquatic environment due to reduction of iron and manganese oxides. To sum up, the water seal method can effectively control the disposal of tailings containing sulfide to produce acid oxidation, so that to inhibit the release of metals. But it could not inhibit the release of transition metals or the metal in the form of metal oxides.

结合广州大学所处广州大学城独特的地理位置,在校园水质监测综合性设计实验教学过程中不断优化教学内容,创新教学方法和手段,充分发挥学生分析问题、解决问题的综合应用能力及创新意识和设计能力,以期达到培养高素质创新型应用型人才的目标.

A novel storage system - NebulaStorage is proposed to solve the storage challenge wall for high performance computer. NebulaStorage designs a new storage architecture in which computing and storage subsystems are loosely coupled. It uses embedded thin storage nodes to build massive storage, and uses software-based erasure code to replace the popular RAID disk array. Simulation tests show that its scalability and fault tolerance ability are better than mainstream luster parallel file system.

数字系统设计和信号完整性工程师面对25Gbps信号传输挑战时,必须重视差分对内偏斜这个关键问题。先介绍差分对内偏斜产生的原因,然后从时域、频域分析了差分对内偏斜对25Gbps背板信号完整性的影响,通过基于测试的通道仿真估算25Gbps信号传输的差分对内偏斜容限;最后,提出了减少差分对内偏斜的工程处理方法。