Implementing minimal clock skew Directed Logic

Although the physics of computing allows the possibility of logic operations with no energy dissipation, over 40 years of work by brilliant scientists in many fields has not achieved it. The solution described here required breaking from the tacit assumptions that logic gates had to be electronic. The system is implemented entirely with passive optical components. Also needed was a logic that could utilize those passive components. Hardy and Shamir showed how to map a Boolean logic problem into a form suitable to be implemented by light flowing through various paths and cascaded as needed. This paper examines a modular approach to implementing their approach (called Directed Logic) in an integrated optical system. We start from unit cells, implementing a dynamic flip-flop principle and combine the cells in a network or “logic fabric.” Contrary to proofs by the founders of this field, speed is limited only by the message bandwidth of the optical signal, and, of course, no energy is dissipated. There are still aspects that need additional work on issues like accuracy using analog components and size relative to electronics. But the basic problem is solved at last and paths toward solving the remaining problems have been identified.     

Method of all-optical frequency-encoded binary adder system using nonlinear waveguide and reflecting semiconductor optical amplifiers

Arithmetic and algebraic operations are the most important part of optical computation and data processing. To implement the optical logic operations, different data encoding/decoding techniques have been reported. Frequency variant encoding/decoding technique is now performing a very faithful role in this regard. Frequency is the fundamental character of any signal and it remains unaltered in reflection, refraction, absorption, etc. during propagation and transmission of the signal. This is the most potential advantage of the frequency encoding technique over any other conventional encoding techniques. Here, in our proposed scheme of addition of binary bits made of two encoded frequencies in C-band (1535-1560 nm), the conjugate beam is generated in LiNbO₃ waveguide using cascaded sum and difference frequency generation by the nonlinear interaction with a third frequency, exploiting the nonlinear response character of periodically poled LiNbO₃ waveguide. The cross-gain modulation property of reflecting semiconductor optical amplifier (RSOA) has also been exploited here for frequency conversion purposes.     

激光对分子振动态的控制与量子Fredkin逻辑门

基于激光相干合成分子的局域模振动态,提出利用激光对分子振动态的控制实现量子Fredkin逻辑门的功能,并对方案的特点及可行性进行分析.     

Multiple Polarization Encoding for Gray Image Encryption Based on Liquid Crystal Exclusive OR Logic

This work proposes and demonstrates the feasibility of gray image encryption using multiple polarization encoding, in which the cascaded twisted nematic liquid crystal devices sandwiched between a crossed polarizer pair are used to implement exclusive OR (XOR) logical encryption and decryption. The polarization encoding scheme provides a multichannel XOR logic operation to secure bit-plane images derived from a gray image, according to the adiabatic following properties of twisted nematic liquid crystal devices. Experimental data reveal that the multiple polarization encoding schemes for gray image encryption and decryption are performed with acceptable image quality by selecting appropriate polarization orientation and modulation conditions. Both analytic and experimental results are presented and discussed.     

Metric of States

Metric of quantum states plays an important role in quantum information theory. In this letter, we find the deep connection between quantum logic theory and quantum information theory. Using the method of quantum logic, we can get a famous inequality in quantum information theory, and we answer a question raised by S. Gudder.     

应用 M IS 时序部件设计一般时序电路

本文提出把可同步激励的MSI时序部件当作一个多功能的复杂存储元件使用,并对计数型MSI与移位型MSI分别给出了它们的次态方程与激励表.此外,提出了应用这两种MSI时序部件设计一般时序电路的状态安排规则及设计程序.讨论表明,这种设计方法在本质上相当于对专用MSI时序部件的基本工作时序进行时序修改.     

深海低声速沉积层简正波用于海底参数反演*

现有深海地声参数反演研究通常基于全波场理论,存在计算量大、多值性以及需要准确的水文环境信息等问题。针对这一问题,提出一种基于简正波频散特征的深海低声速沉积层海底参数反演方法。在南海北部大陆坡海域的一次实验中,坐底式水听器(深度约1740 m)接收的沉底弹信号中观察到一种低频成分先到而高频成分后至的到达结构,由被限制在低声速沉积层的简正波组成。通过匹配沉积层简正波60-220 Hz频段内的到达时间差对实验海域的低声速海底参数进行反演,得到沉积层厚度为16.4 m,沉积层声速为1450.5 m/s,与底质采样数据比较吻合,且具有较高的可信度,验证了所提方法的有效性。由于沉积层密度对简正波频散特征的敏感性较差,其反演结果可信度不是很高,需要进一步研究。     

High throughput N-modular redundancy for error correction design of memristive stateful logic

Memristive stateful logic is one of the most promising candidates to implement an in-memory computing system that computes within the storage unit. It can eliminate the costs for the data movement in the traditional von Neumann system. However, the instability in the memristors is inevitable due to the limitation of the current fabrication technology, which incurs a great challenge for the reliability of the memristive stateful logic. In this paper, the implication of device instability on the reliability of the logic event is simulated. The mathematical relationship between logic reliability and redundancy has been deduced. By combining the mathematical relationship with the vector-matrix multiplication in a memristive crossbar array, the logic error correction scheme with high throughput has been proposed. Moreover, a universal design paradigm has been put forward for complex logic. And the circuit schematic and the flow of the scheme have been raised. Finally, a 1-bit full adder (FA) based on the NOR logic and NOT logic is simulated and the mathematical evaluation is performed. It demonstrates the scheme can improve the reliability of the logic significantly. And compared with other four error corrections, the scheme which can be suitable for all kinds of R-R logics and V-R logics has the best universality and throughput. Compared with the other two approaches which also need additional complementary metal-oxide semiconductor (CMOS) circuits, it needs fewer transistors and cycles for the error correction.     

Distributions in fuzzy logic

Probability distributions associated with several ‘ply’-operators are discussed. These exact distributions are compared with relevant Gaussian approximations.     

Enzyme-free and DNA-based universal platform for the construction of various logic devices based on graphene oxide and G-quadruplex

In the fields of biocomputing and biomolecular, DNA molecules are applicable to be regarded as data of logical computing platform that uses elaborate logic gates to perform a variety of tasks. Graphene oxide (GO) is a type of novel nanomaterial, which brings new research focus to materials science and biosensors due to its special selectivity and excellent quenching ability. G-quadruplex as a unique DNA structure stimulates the intelligent application of DNA assembly on the strength of its exceptional binding activity. In this paper, we report a universal logic device assisted with GO and G-quadruplex under an enzyme-free condition. Integrated with the quenching ability of GO to the TAMRA (fluorophore, Carboxytetramethylrhodamine) and the enhancement of fluorescence intensity produced by the peculiar binding of G-quadruplex to the NMM (N-methylmesoporphyrin IX), a series of basic binary logic gates (AND. OR. INHIBIT. XOR) have been designed and verified through biological experiments. Given the modularity and programmability of this strategy, two advanced logic gates (half adder and half subtractor) were realized on the basis of the same work platform. The fluorescence signals generated from different input combinations possessed satisfactory results, which provided proof of feasibility. We believe that the proposed universal logical platform that operates at the nanoscale is expected to be utilized for future applications in molecular computing as well as disease diagnosis.