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1.
Programmable memory built‐in self‐test (PMBIST) is an attractive approach for testing embedded memory. However, the main difficulties of the previous works are the large area overhead and low flexibility. To overcome these problems, a new flexible PMBIST (FPMBIST) architecture that can test both single‐port memory and dual‐port memory using various test algorithms is proposed. In the FPMBIST, a new instruction set is developed to minimize the FPMBIST area overhead and to maximize the flexibility. In addition, FPMBIST includes a diagnostic scheme that can improve the yield by supporting three types of diagnostic methods for repair and diagnosis. The experiment results show that the proposed FPMBIST has small area overhead despite the fact that it supports various test algorithms, thus having high flexibility.  相似文献   

2.
While microparticle (MP) assemblies have long attracted academic interest, few practical applications of assembled MPs have been achieved because of technological difficulties related to MP synthesis, MP position registration, and the absence of device concepts. The precise positioning of functional MPs in a proper stencil can produce flexible/stretchable electronic devices, even when the MPs themselves are rigid. In recent years, remarkable progress has been made in the programmable position registration of MPs, production of functional MPs, and concepts for MP‐based, pixel‐type electronic devices. This progress report reviews the recent technological advances in MP assembly and discusses the technological challenges preventing the realization of the one‐particle/one‐pixel concept.  相似文献   

3.
This paper proposes a test algorithm that can detect and diagnose all the faults occurring in dual‐port memories that can be accessed simultaneously through two ports. In this paper, we develop a new diagnosis algorithm that classifies faults in detail when they are detected while the test process is being developed. The algorithm is particularly efficient because it uses information that can be obtained by test results as well as results using an additional diagnosis pattern. The algorithm can also diagnose various fault models for dual‐port memories.  相似文献   

4.
This paper proposes the semaphore authority management (SAM) controller to optimize the dual‐port SDRAM (DPSDRAM) in the mobile multimedia systems. Recently, the DPSDRAM with a shared bank enabling the exchange of data between two processors at high speed has been developed for mobile multimedia systems based on dual‐processors. However, the latency of DPSDRAM caused by the semaphore for preventing the access contention at the shared bank slows down the data transfer rate and reduces the memory bandwidth. The methodology of SAM increases the data transfer rate by minimizing the semaphore latency. The SAM prevents the latency of reading the semaphore register of DPSDRAM, and reduces the latency of waiting for the authority of the shared bank to be changed. It also reduces the number of authority requests and the number of times authority changes. The experimental results using a 1 Gb DPSDRAM (OneDRAM) with the SAM controllers at 66 MHz show 1.6 times improvement of the data transfer rate between two processors compared with the traditional controller. In addition, the SAM shows bandwidth enhancement of up to 38% for port A and 31% for port B compared with the traditional controller.  相似文献   

5.
张胜  李瑞民 《电视技术》2016,40(7):36-39
串口的广泛使用,得益于小到单片机,大到多核CPU的直接支持,所以在设备中,特别是广电行业设备中,不仅不会消失,而且还会长期存在.然而串口通信具有独占性,一旦一个监控程序占用了某个串口,则另外的程序无法使用该串口,这对于二次开发、第三方监控、设备共享、硬件设备的调试和测试都十分不利.所以,对串口嗅探技术的研究是有必要的,目前国内尚无人对此做出过研究,通过三个层次,共提出五种串口嗅探技术,每一种串口嗅探技术都有自己独特的地方,但也都有不足之处,但无论是功能上,还是性能上都可以满足串口嗅探的功能.最后,通过程序的设计和测试,验证了方法的可能性.  相似文献   

6.
Broadcasting is one of the most important communication primitives used in multiprocessor networks. In this letter, we demonstrate that the broadcasting algorithm proposed by Madabhushi and others is incorrect. We introduce efficient one-to-all broadcasting schemes of even networks for one-port and all-port models. The broadcasting time of the one-port model is 2d-3 and that of the all-port model is d-1. The total time steps taken by the proposed algorithms are optimal.  相似文献   

7.
Hybrid digital multimedia broadcasting (DMB) is a next‐generation mobile TV system that combines broadcasting and wireless communication networks and can provide various high‐quality multimedia services. However, if a system adheres to the current standard of transmitting the DMB content in the form of MPEG2‐TS through wireless networks, it results in a burden on the network due to low transmission efficiency. The reasons for the low transmission efficiency are as follows. First, due to its constant bitrate characteristic, DMB MPEG2‐TS includes a considerable amount of needless information, such as NULL packets and stuffing bytes. Second, due to the inflexibility of the Real‐time Transport Protocol (RTP) standard, one cannot fully utilize the maximum transmission unit of the network when converting MPEG2‐TS to RTP stream for transmission. This paper proposes a new transmission scheme that resolves these problems. Experiment results show that the proposed scheme improves data bitrate transmission efficiency by 8% to 36%, compared to the standard scheme, in the streaming of various real‐DMB contents.  相似文献   

8.
With large surface‐to‐volume ratios and Debye length comparable to their small sizes, one‐dimensional inorganic nanostructures have extensively been investigated and widely used to fabricate high‐performance nano­scale electronic and optoelectronic devices. This feature article reviews the state‐of‐the‐art research activities that focus on the one‐dimensional inorganic nanostructures and their photodetector applications. It begins with a survey of one‐dimensional inorganic nanostructures and the fundamentals of photodetectors. Some remarkable photoresponse characteristics are then presented, which are organized into sections covering several kinds of important nanostructures, such as ZnO, V2O5, ZnS, In2Se3, InSe, CdS, CdSe, ZnSe, Sb2Se3, ZrS2, Ag2S, and ZnxCd1‐xSe. Each section describes the corresponding photodetective properties in detail. Finally, the article concludes with some perspectives and outlook on the future developments in the field.  相似文献   

9.
Skin wound therapy aims not only to restore skin protection but also to recover excitation functions through nerve regeneration. During the restoration of skin nerves, the recruitment of endogenous stem cells and promotion of neuronal regeneration on site work stepwise are foundations of in situ regeneration. However, current therapeutic systems usually execute each process separately, leading to limited regeneration and recovery of excitation functions. Herein, a novel self‐adaptive all‐in‐one delivery chip (G:P:Al‐Chip) is constructed that combines therapeutic protein release, gene delivery, and electrical conduction in a single microfluidic chip by 3D coaxial printing. G:P:Al‐Chip consists of an outer conductive hydrogel shell anchored with chemokine and an inner microchannel filled with enzyme‐initiated vector/plasmid DNAs microcomplexes. G:P:Al‐Chip delivers chemokine, functional plasmid DNAs, and promotes electrical conduction with a self‐adaptive program that significantly enhances the recruitment of endogenous mesenchymal stem cells and promotes neuronal regeneration. G:P:Al‐Chip is shown to enhance nerve regeneration with excitation functions within 23 days. G:P:Al‐Chip organizes recruitment and neuronal regeneration cues along with bioelectrical signal in one degradable chip for accelerated skin nerve regeneration.  相似文献   

10.
This paper proposes printed organic one‐time programmable read‐only memory (PROM). The organic PROM cell consists of a capacitor and an organic p‐type metal‐oxide semiconductor (PMOS) transistor. Initially, all organic PROM cells with unbroken capacitors store “0.” Some organic PROM cells are programmed to “1” by electrically breaking each capacitor with a high voltage. After the capacitor breaking, the current flowing through the PROM cell significantly increases. The memory data is read out by sensing the current in the PROM cell. 16‐bit organic PROM cell arrays are fabricated with the printed organic PMOS transistor and capacitor process. The organic PROM cells are programmed with –50 V, and they are read out with –20 V. The area of the 16‐bit organic PROM array is 70.6 mm2.  相似文献   

11.
This letter proposes a new low‐complexity motion estimation method. The proposed method classifies various nonmatching pixel pairs into several categories and assigns an appropriate weight for each category in the matching stage. As a result, it can significantly improve performance compared to that of the conventional methods by adding only one 1‐bit addition and two Boolean operations per pixel.  相似文献   

12.
Triple‐shape polymers can move from a first shape (A) to a second shape (B) and from there to a third shape (C), where both shape changes are induced by temperature increases. This triple‐shape capability is obtained for multiphase polymer networks after application of a complex thermomechanical programming process, which consists of two steps; these steps create shapes (B) and (A), while shape (C) is defined by the covalent crosslinks of the polymer network. Here, the creation of the triple‐shape capability for an AB polymer network system by a simple one‐step process similar to a conventional dual‐shape programming process is reported. The polymer networks are based on poly(ε‐caprolactone) (PCL) and poly(cyclohexyl methacrylate); favorable compositions for obtaining a triple shape effect have a PCL content between 35 and 60 wt%. This finding substantially facilitates handling of the triple‐shape technology and is an important step toward the realization of potential applications in which more than one shape change is required.  相似文献   

13.
The wireless sensor network (WSN) has attracted lots of attention recently. Broadcast is a fundamental operation for all kinds of networks and it has not been addressed seriously in the WSN. Therefore, we propose two types of power and time efficient broadcasting protocols, namely one‐to‐all and all‐to‐all broadcasting protocols, for five different WSN topologies. Our one‐to‐all broadcasting protocols conserve power and time by choosing as few relay nodes as possible to scatter packets to the whole network. Besides, collisions are carefully handled such that our one‐to‐all broadcasting protocols can achieve 100% reachability. By assigning each node a proper channel, our all‐to‐all broadcasting protocols are collision free and efficient. Numerical evaluation results compare the performance of the five topologies and show that our broadcasting protocols are power and time efficient. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

14.
The capacity of wireless networks can be improved by the use of multi‐channel multi‐interface (MCMI), multi‐packet reception (MPR), and directional antenna (DA). MCMI can provide the concurrent transmission in different channels for each node with multiple interfaces; MPR offers an increased number of concurrent transmissions on the same channel; DA can be more effective than omni‐DA by reducing interference and increasing spatial reuse. This paper explores the capacity of wireless networks that integrate MCMI, MPR, and DA technologies. Unlike some previous research, which only employed one or two of the aforementioned technologies to improve the capacity of networks, this research captures the capacity bound of the networks with all the aforementioned technologies in arbitrary and random wireless networks. The research shows that such three‐technology networks can achieve at most capacity gain in arbitrary networks and capacity gain in random networks compared with MCMI wireless networks without DA and MPR. The paper also explored and analyzed the impact on the network capacity gain with different , θ, and k‐MPR ability. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

15.
基于Hybrid Port的VLAN实现   总被引:1,自引:0,他引:1  
周蓉蓉  陈刚 《现代电子技术》2005,28(16):102-104
VLAN具有控制网络广播风暴、保障网络安全和简化网络管理等特点,因此在局域网中得到广泛的应用。在某些场合下必须允许特定VLAN之间相互访问,通常实现方式是划分IP子网并通过IP进行路由。但是在某些特定的场合中,由于IP紧缺以及保障IP真实等原因,不能采取这样的方案。为此本文提出了一种基于混杂端口(hybrid port)的虚拟局域网(VLAN)实现方案。通过这种方式设计,在提高网络安全性的同时,避免了IP地址紧缺的问题。最后给出了基于混杂端口VLAN设计方案。  相似文献   

16.
In multihop wireless networks, delivering a packet to all nodes within a specified geographic distance from the source is a packet forwarding primitive (geography‐limited broadcasting), which has a wide range of applications including disaster recovery, environment monitoring, intelligent transportation, battlefield communications, and location‐based services. Geography‐limited broadcasting, however, relies on all nodes having continuous access to precise location information, which may not be always achievable. In this paper, we consider achieving geography‐limited broadcasting by means of the time‐to‐live (TTL) forwarding, which limits the propagation of a packet within a specified number of hops from the source. Because TTL operation does not require location information, it can be used universally under all conditions. Our analytical results, which are validated by simulations, confirm that TTL‐based forwarding can match the performance of the traditional location‐based geography‐limited broadcasting in terms of the area coverage as well as the broadcasting overhead. It is shown that the TTL‐based approach provides a practical trade‐off between geographic coverage and broadcast overhead. By not delivering the packet to a tiny fraction of the total node population, all of which are located near the boundary of the target area, TTL‐based approach reduces the broadcast overhead significantly. This coverage‐overhead trade‐off is useful if the significance of packet delivery reduces proportionally to the distance from the source. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

17.
Vehicular wireless networks offer wireless multi‐hop communications between vehicles and roadside units (RSUs). To reduce deployment cost, the distance between two RSUs could be long; that is, the communications between an RSU and a vehicle may be carried out through multi‐hops among intermediate vehicles. When a vehicle is driven from one RSU to another, the wireless multi‐hop delay becomes more serious as the number of multi‐hop relays increases. The wireless multi‐hop delay is critical for some emergency service. For instance, in a traffic accident, when a patient was sent to the hospital by ambulance, the life information of the patient must be transmitted to the hospital on time through the multi‐hop wireless network. If the ambulance is moved from one RSU to another, the wireless multi‐hop delay becomes more and more serious as the ambulance is closing to another RSU. In this paper, we propose an RSU re‐routing strategy that dynamically alters multi‐hop communications until the best RSU with the shortest path using location information is found. Moreover, we compare the proposed strategy with the existing strategy in terms of broadcasting costs, re‐routing delay, and wireless multi‐hop delay of data transmission. Performance results show that the proposed strategy can reduce the wireless multi‐hop delay significantly. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

18.
ZnS:M2+ (M = Mn, Co, or Cu) single‐crystal one‐dimensional nanostructures have been prepared via a simple halide‐transport chemical vapor deposition (HTCVD) process at a relatively low temperature. The obvious phase transition suggests that doping with Mn favors the formation of the hexagonal phase at a relative low temperature. The strong photoluminescence from blue to green and the yellow–orange emission, which was caused by the doping of various elements in ZnS nanowires and nanobelts, suggests possible applications of the one‐dimensional nanostructures in nanoscale optoelectronic devices.  相似文献   

19.
Due to its high spectrum efficiency, 64‐amplitude phase‐shift keying (64‐APSK) is one of the primary technologies used in deep space communications and digital video broadcasting through satellite‐second generation. However, 64‐APSK suffers from considerable computational complexity because of the de‐mapping method that it employs. In this study, a low‐complexity de‐mapping method for (4 + 12 + 20 + 28) 64‐APSK is proposed in which we take full advantage of the symmetric characteristics of each symbol mapping. Moreover, we map the detected symbol to the first quadrant and then divide the region in this first quadrant into several partitions to simplify the formula. Theoretical analysis shows that the proposed method requires no operation of exponents and logarithms and involves only multiplication, addition, subtraction, and judgment. Simulation results validate that the time consumption is dramatically decreased with limited degradation of bit error rate performance.  相似文献   

20.
1D metal‐oxide nanostructures have attracted much attention because metal oxides are the most fascinating functional materials. The 1D morphologies can easily enhance the unique properties of the metal‐oxide nanostructures, which make them suitable for a wide variety of applications, including gas sensors, electrochromic devices, light‐emitting diodes, field emitters, supercapacitors, nanoelectronics, and nanogenerators. Therefore, much effort has been made to synthesize and characterize 1D metal‐oxide nanostructures in the forms of nanorods, nanowires, nanotubes, nanobelts, etc. Various physical and chemical deposition techniques and growth mechanisms are exploited and developed to control the morphology, identical shape, uniform size, perfect crystalline structure, defects, and homogenous stoichiometry of the 1D metal‐oxide nanostructures. Here a comprehensive review of recent developments in novel synthesis, exceptional characteristics, and prominent applications of one‐dimensional nanostructures of tungsten oxides, molybdenum oxides, tantalum oxides, vanadium oxides, niobium oxides, titanium oxides, nickel oxides, zinc oxides, bismuth oxides, and tin oxides is provided.  相似文献   

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