A hybrid attention deep learning network for refined segmentation of cracks from shield tunnel lining images

This research developed a hybrid position-channel network (named PCNet) through incorporating newly designed channel and position attention modules into U-Net to alleviate the crack discontinuity problem in channel and spatial dimensions. In PCNet, the U-Net is used as a baseline to extract informative spatial and channel-wise features from shield tunnel lining crack images. A channel and a position attention module are designed and embedded after each convolution layer of U-Net to model the feature interdependencies in channel and spatial dimensions. These attention modules can make the U-Net adaptively integrate local crack features with their global dependencies. Experiments were conducted utilizing the dataset based on the images from Shanghai metro shield tunnels. The results validate the effectiveness of the designed channel and position attention modules, since they can individually increase balanced accuracy (BA) by 11.25% and 12.95%, intersection over union (IoU) by 10.79% and 11.83%, and F1 score by 9.96% and 10.63%, respectively. In comparison with the state-of-the-art models (i.e. LinkNet, PSPNet, U-Net, PANet, and Mask R–CNN) on the testing dataset, the proposed PCNet outperforms others with an improvement of BA, IoU, and F1 score owing to the implementation of the channel and position attention modules. These evaluation metrics indicate that the proposed PCNet presents refined crack segmentation with improved performance and is a practicable approach to segment shield tunnel lining cracks in field practice.

Construction of Non-Symmetric Balanced Incomplete Block Design through Combination of Symmetric Disjoint Balanced Incomplete Block Designs

The existence of several non-symmetric balanced incomplete block designs (BIBDs) is still unknown. This is because the non-existence property for non-symmetric BIBDs is still not known and also the existing construction methods have not been able to construct these designs despite their design parameters satisfying the necessary conditions for the existence of BIBD. The study aimed to bridge this gap by introducing a new class of non-symmetric BIBDs. The proposed class of BIBDs is constructed through the combination of disjoint symmetric BIBDs. The study was able to determine that the total number of disjoint symmetric BIBDs (n) with parameters (v = b, r = k, λ) that can be obtained from an un-reduced BIBD with parameters (v, k) is given by n = r - λ. When the n symmetric disjoint BIBDs are combined, then a new class of symmetric BIBDs is formed with parameters v* = v, b* = nb, r* = nr, k* = k, λ* = λ, where 2≤ n ≤ r - λ. The study established that the non-existence property of this class of BIBD was that when is not a perfect square then v should be even and when v* is odd then the equation should not have a solution in integers x, y, z which are not all simultaneously zero. In conclusion, the study showed that this construction technique can be used to construct some non-symmetric BIBDs. However, one must first construct the disjoint symmetric BIBDs before one can construct the non-symmetric BIBD. Thus, the disjoint symmetric BIBDs must exist first before the non-symmetric BIBDs exist.

可证明安全的节点不相交多路径源路由协议

多路径路由实现是移动ad hoc网络可靠运行的有效保证.针对多路径路由协议的安全性分析,建立了基于UC(universally composable)框架的可证明安全路由协议的新方法.基于攻陷的网络拓扑模型,扩展了可模糊路由概念,提出了多路径可模糊路由集合概念,用于描述攻陷网络拓扑结构的移动ad hoc网络多路径路由;基于UC安全模型,提出了基于UC-RP(universally composable security framework for ad hoc networks routing protocol)框架的路由协议形式化安全定义;针对MNDP(multiple node-disjoint paths)协议存在的安全问题,提出了新的移动ad hoc网络节点不相交多路径动态源路由协议(简记为SMNDP(security multiple node-disjoint paths)协议).将基于UC-RP框架的可证明安全路由协议的新方法应用于SMNDP协议的安全分析.SMNDP协议的可证明安全性可以归约为消息认证码和签名机制的安全性.SMNDP协议实现了路由发现协议的正确性、节点身份的认证性和路由消息的完整性.

一种基于多值逻辑的开放式逻辑软件设计方法

在工业控制系统中，将对逻辑测控过程的表述抽象成多值逻辑是一种准确而又便利的方法，同时，测控过程的多样性又使传统的利用程序设计语言中逻辑语句的软件设计方法很难适应对开放性的要求．本文提出一种适合多值逻辑处理的数据结构和代数系统，并以此为基础，构造逻辑描述式，实现组合多值逻辑和时序多值逻辑的开放式设计．

一种关于数据流区间Disjoint查询的快速处理算法

在关于数据流子序列相似性匹配的研究中,Disjoint查询是很重要的一类,在传感网络和数据挖掘等方面都发挥着非常重要的作用.但现有的研究并没有关注到定长区间上的Disjoint查询问题.直接对每个区间内成员使用Spring算法是解决该问题的NAIVE算法,但是因为NAIVE算法不具有增量计算的特点,所以存在冗余运算.针对NAIVE算法冗余运算的处理问题,提出了边界路径技术.边界路径技术很好地使用了Spring算法在相邻前一区间上的执行结果,使得Spring算法无需对当前区间上每个成员执行,就可以得到Disjoint查询在该区间的查询结果.使用该技术对NAIVE算法进行改造,设计并实现了快速区间Disjoint查询处理算法(fast section Disjoint query processing algorithm,FSDQ),该算法具有增量计算的特点.实验证明FSDQ算法可以有效减少NAIVE算法所具有的冗余运算,是处理数据流上区间Disjoint查询的有效方法.

句法不确定性与诗词翻译——以红楼梦柳絮词为例

翻译的不确定性源自意义的不确定性和指称的不可测知性。诗词的多值性给了读者充裕的想象空间,而翻译的过程却要将这种多值化解为单值。针对这一点提出在翻译意象并置引起的不确定性时,可以采用DT(disjointed translation)模式;在其他情况下,要利用互确定性和诗性思维对原诗词进行分析,用音乐性的节奏或对意象的操控来消减"多值-单值"的损失,同时赋予诗作以新生。

一种滑动窗口下数据流Disjoint查询的增量处理算法

对于滑动窗口下不具有全局约束机制的数据流Disjoint查询精确处理问题进行了研究,在现有FSM算法基础上提出了一种具有增量计算特征的查询处理算法DQPIC.该算法使用FSM算法处理第一个窗口中的数据流成员,同时保留了该窗口上的查询结果和窗口所对应STWM的最后一个列向量,除此之外还需要保留窗口STWM中所有列向量第curbound.highest个成员DTW路径的起始位置、距离值以及该成员在STWM中对应列向量的dmin值和候选查询结果这些信息.从第二个窗口开始,继续使用FSM算法处理窗口成员,同时也保留和第一个窗口一样的信息.在这个过程中,当处理相邻窗口中相同数据流成员时,通过比较该成员在前后两个窗口中分别对应的保留信息是否相同,可以确定算法有无继续处理剩余相同数据流成员的必要,能够在前一个窗口查询结果基础上增量地获得当前窗口查询结果.基于公用数据样本SST与Maskedchirp的仿真实验验证了该算法的有效性.提出的算法与现有其他算法执行结果相同,在空间开销增加1.12~3.27倍情况下,可以实现时间效率2.5~25倍的提高,对于与大窗口下的Disjoint查询相关应用场景,具有更好的时间效果.

A disjoint algorithm for seismic reliability analysis of lifeline networks

The algorithm is based on constructing a disjoin kg t set of the minimal paths in a network system.In this paper, cubic notation was used to describe the logic function of a network in a well-balanced state,and then the sharp-product operation was used to construct the disjoint minimal path set of the network.A computer program has been developed,and when combined with decomposition technology,the reliability of a general lifeline network can be effectively and automatically calculated.

On the Gracefulness of Graph(jC_(4n))∪P_m

The present paper deals with the gracefulness of unconnected graph （jC_（4n））∪P_m,and proves the following result：for positive integers n,j and m with n≥1,j≥2,the unconnected graph（jC_（4n））∪P_m is a graceful graph for m=j-1 or m≥n＋j,where C_（4n） is a cycle with 4n vertexes,P_m is a path with m＋1 vertexes,and（jC_（4n））∪P_m denotes the disjoint union of j-C_（4n） and P_m.

Artin单环的正向极限

假设Ⅰ是一个正向指标集,R_i是Artin单环,i∈Ⅰ,{R_i,p^i_f}是Ⅰ上一个正向系统。容易知道,正向极限lim R_i并非一定是一个Artin单环。本文证明了定理假设正向指标集Ⅰ是可数集合,令{R_i,~i_f}是一个 Artin单环的正向系统。那么,R=lim R_i是一个本原环。并且求得 l.gl.dimR≤1, 即R=limR_i还是一个遗传环。

Disjoint双线性规划的一个混合整数线性规划变换及其应用

针对disjoint双线性规划问题,给出了一个混合整数线性规划变换方法,以求得其全局最优解。该方法将disjoint双线性规划变换为一个带有互补约束的线性规划,并利用0-1变量和大M法线性化互补约束。同时,将该方法应用于金融系统中的不确定性系统性风险估计问题,证明了该问题可变换为一个disjoint双线性规划问题,进而利用所提出的方法求解。数值结果表明:提出的方法能有效找到中大规模最坏情形系统性风险估计问题的全局最优解,并优于已有的全局解方法。

DISJOINT SUPERCYCLIC WEIGHTED PSEUDO-SHIFTS ON BANACH SEQUENCE SPACES

In this article, we present several equivalent conditions ensuring the disjoint supercyclicity of finite weighted pseudo-shifts acting on an arbitrary Banach sequence space. The disjoint supercyclic properties of weighted translations on locally compact discrete groups, the di rec t sums of finite classical weighted backward shifts, and the bilateral backward opera tor weighted shifts can be viewed as special cases of our main results. Furthermore, we exhibit an interesting fact that any finite bilateral weighted backward shifts on the space l^2 (Z) never satisfy the d-Supercyclicity Criterion by a simple proof.

An improved recursive decomposition algorithm for reliability evaluation of lifeline networks

The seismic reliability evaluation of lifeline networks has received considerable attention and been widely studied. In this paper, on the basis of an original recursive decomposition algorithm, an improved analytical approach to evaluate the seismic reliability of large lifeline systems is presented. The proposed algorithm takes the shortest path from the source to the sink of a network as decomposition policy. Using the Boolean laws of set operation and the probabilistic operation principal, a recursive decomposition process is constructed in which the disjoint minimal path set and the disjoint minimal cut set are simultaneously enumerated. As the result, a probabilistic inequality can be used to provide results that satisfy a prescribed error bound. During the decomposition process, different from the original recursive decomposition algorithm which only removes edges to simplify the network, the proposed algorithm simplifies the network by merging nodes into sources and removing edges. As a result, the proposed algorithm can obtain simpler networks. Moreover, for a network owning s-independent components in its component set, two network reduction techniques are introduced to speed up the proposed algorithm. A series of case studies, including an actual water distribution network and a large urban gas system, are calculated using the proposed algorithm. The results indicate that the proposed algorithm provides a useful probabilistic analysis method for the seismic reliability evaluation of lifeline networks.

Variations and Absolute Continuity of Set Functions on T_∞-tribe

some properties of the inclusion variation and the disjoint variation of set functions on T∞-tribe are studied in detail.The absolute continuity and singularity of set functions on T∞-tribe are discussed.The triangular norms T∞ and S∞ are considered as the operators of intersection and union between the fuzzy sets.As a result,some important conclusions about the variations and absolute continuity of set functions on T∞-tribe are obtained such as the superadditivity of inclusion variation,the relation between the variations and the equivalence proposition of absolute continuity of set functions on T∞-tribe.In addition,two small mistakes about T∞-measure are pointed out by the counterexamples and are revised.

FINITENESS OF HIGHER CODIMENSIONAL DISJOINT MINIMAL GRAPHS

We estimate the number of disjoint open subsets in Rn, which can support area-decreasing minimal graphs. This result generalizes the related results of Li-Wang and Tkachev for minimal hypersurfaces to higher codimensional case.

Reinforcing a Matroid to Have k Disjoint Bases

Let denote the maximum number of disjoint bases in a matroid . For a connected graph , let , where is the cycle matroid of . The well-known spanning tree packing theorem of Nash-Williams and Tutte characterizes graphs with . Edmonds generalizes this theorem to matroids. In [1] and [2], for a matroid with , elements with the property that have been characterized in terms of matroid invariants such as strength and -partitions. In this paper, we consider matroids with , and determine the minimum of , where is a matroid that contains as a restriction with both and . This minimum is expressed as a function of certain invariants of , as well as a min-max formula. These are applied to imply former results of Haas [3] and of Liu et al. [4].

On the Decomposition of a Bounded Closed Interval of the Real Line into Closed Sets

It has been shown by Sierpinski that a compact, Hausdorff, connected topological space (otherwise known as a continuum) cannot be decomposed into either a finite number of two or more disjoint, nonempty, closed sets or a countably infinite family of such sets. In particular, for a closed interval of the real line endowed with the usual topology, we see that we cannot partition it into a countably infinite number of disjoint, nonempty closed sets. On the positive side, however, one can certainly express such an interval as a union of c disjoint closed sets, where c is the cardinality of the real line. For example, a closed interval is surely the union of its points, each set consisting of a single point being closed. Surprisingly enough, except for a set of Lebesgue measure 0, these closed sets can be chosen to be perfect sets, i.e., closed sets every point of which is an accumulation point. They even turn out to be nowhere dense (containing no intervals). Such nowhere dense, perfect sets are sometimes called Cantor sets.

QoS Aware Routing Protocol to Improve Packet Transmission in Shadow-Fading Environment for Mobile Ad Hoc Networks

In Shadow-Fading model, it is difficult to achieve higher Packet Delivery Ratio (PDR) due to the effects of large scale fading. The main goal of this paper is to improve the PDR in Shadow-Fading environment. To achieve this objective a protocol has been proposed that discovers backup routes for active sessions. These backup routes salvage the packets of active session in case of active route failure. It is found by research that proactively maintaining backup routes for ac-tive sessions can noticeably improve the PDR in Shadow-Fading environment. This protocol has been implemented with a mechanism of having backup routes and simulations have been conducted by using both node disjoint paths and link disjoint paths. Comparisons have been made between new protocol as well as AODV protocol. Simulation has been carried out using Network Simulator 2 (NS2) and the results show that the proposed QoSAR protocol exhibits higher PDR than AODV protocol in Shadow-fading environment.

MSDM: Maximally Spatial Disjoint Multipath Routing Protocol for MANET

Mobile Ad-hoc Network (MANET) consists of mobile nodes that are connected via very dynamic multi-hop channels. Routing in MANET is a challenging task that has received great attention from researchers. In this paper we present Maximally Spatial Disjoint Multipath routing protocol (MSDM) which is a modification of AOMDV protocol. MSDM finds paths which are spatially separated and maximally disjointed. We think that sending various packets over spatially disjointed paths reduces the probability of collision occurrence and allows concurrent transmission over the set of different selected paths. Performance comparison of MSDM and AOMDV using GloMoSim simulator shows that MSDM is able to achieve a considerable improvement regarding some performance metrics such as delay, routing packets overhead, and network throughput.

On the Existence of Suprema of Infinite Many Elements in a Riesz Space

Let E be a Riesz space with a disjoint system {u_i :i∈I}. We denote by E_i the principal band generated by u_i(i∈I). A necessary and sufficient condition is found in this paper under which sup{X_i:i∈I} exists in E for every x_i∈E (i∈I).