Brief Exploration of Nasal Assimilation Phenomenonin Negative Prefixes-Comparison Between Chinese Dialect & English

Nasals and assimilation are basic terminologies in phonology,nasal assimilation is a kind of common phonological phenomenon in addition.As is known to all,in English,assimilation mainly happens between consonants and consonants,which is one of the important constitutes of English mutation,for the sake of labor-saving convenience and better fluency.From an applied linguistic view,nasal assimilation in negative prefixes(e.g.un-,ab-,ir-,im-&non-,etc.)is seemingly another interesting phenomenon for an innovative exploration.This paper focuses on some specific enumeration and comparison between Chinese dialect(specifically,Sichuan dialect)as well as English.This brief exploration and analysis might contribute to relative study in years to come.

Negative prefixes“un-”and“non-”

In English,there are negative prefixes as“a-,ab-,anti-,counter-,de-,dis-,il-,im-,in-,ir-,mal-,mis-,non-,un-andetc.Among them,we are often confused about the usage of“un-”and“non-”.According to the work the distinctive semantic features between un- and non-,there are three main points helping usdistinguish them:different concepts,different tone and emotion,and different meanings of antonyms.Based on these three points,the article is going to analyze the third distinction:different meanings of antonyms.

The Analysis of Prefixes——Taking mal-and mis-As Examples

The present paper is aimed to testify that the richness and abundance of English vocabulary is closely related to prefixes. Through the analysis of prefixes such as mal-and mis-, a better understanding of word formation from the perspective of semantic factors and functional factors as well as morphology factors will be obtained.

Towards Blockchain-Based Secure BGP Routing,Challenges and Future Research Directions

Border Gateway Protocol(BGP)is a standard inter-domain routing protocol for the Internet that conveys network layer reachability information and establishes routes to different destinations.The BGP protocol exhibits security design defects,such as an unconditional trust mechanism and the default acceptance of BGP route announcements from peers by BGP neighboring nodes,easily triggering prefix hijacking,path forgery,route leakage,and other BGP security threats.Meanwhile,the traditional BGP security mechanism,relying on a public key infrastructure,faces issues like a single point of failure and a single point of trust.The decentralization,anti-tampering,and traceability advantages of blockchain offer new solution ideas for constructing secure and trusted inter-domain routing mechanisms.In this paper,we summarize the characteristics of BGP protocol in detail,sort out the BGP security threats and their causes.Additionally,we analyze the shortcomings of the traditional BGP security mechanism and comprehensively evaluate existing blockchain-based solutions to address the above problems and validate the reliability and effectiveness of blockchain-based BGP security methods in mitigating BGP security threats.Finally,we discuss the challenges posed by BGP security problems and outline prospects for future research.

基于改进Prefix Span的结构超手册修理方法推荐

针对当前民机结构超手册修理能力提升的迫切需求,提出了一种基于改进Prefix Span的结构超手册修理方法推荐模型。以某型国产民机结构超手册修理案例数据为样本,构建案例特征指标层次并对数据分级和结构化预处理,基于改进Prefix Span算法对案例损伤信息和修理方法频繁序列进行充分挖掘,生成超手册修理关联规则集,通过目标案例和频繁序列间相似度匹配,实现了超手册修理方法的智能推荐。测试结果表明,模型超手册修理方法推荐总准确率可达85.3%,显著高于改进前算法,具备良好的准确性和可用性,可为结构超手册修理决策、方案制定等提供一定的参考依据。

基于数据挖掘的Prefix Span算法网络安全研究

鉴于传统用于网络安全防御的恶意数据检测算法耗时长、识别精度低、适用性差的问题,提出基于数据挖掘的Prefix Span网络安全防御算法研究。该研究在序列模式数据挖掘的理论研究基础上提出了Prefix Span算法,按照序列前缀生成投影数据库并去除非频繁项,引入相关度的概念完成算法的过程优化;基于Prefix Span算法构建了一种网络安全防御模型,对采集到的网络数据实施预处理、序列匹配与判定,实现对入侵数据的识别与检测,确保网络运行安全。仿真实验结果表明,提出的网络安全防御算法能够准确识别出不同类型的入侵数据,在检测精度和检测效率方面都有良好的表现。

巴德Mesh prefix plug在腹股沟疝修补术中的应用

目的：探讨巴德Mesh prefix plug在腹股沟疝修补术中的应用效果。方法：对65例使用巴德Mesh prefixplug无张力修补的腹股沟疝患者进行分析。其中单侧疝61例，双侧疝4例。原发疝56例，复发疝9例。斜疝54例，直疝6例，复合疝5例。结果：手术时间为35～70min。术后阴囊轻度肿胀5例，术后无切口感染及血肿发生。平均住院7d。短期随访效果良好，无复发及腹股沟区明显异物感。结论：巴德Mesh prefix plug适用于成人腹股沟疝修补，特别是老年疝、复发疝的修补尤为适用，是有效、安全、方便的。

对Prolog程序设计教材的几点意见

近年来,人工智能程序设计在工农业、医学、教育、军事等方面得到了应用。如何运用机器进行思维、推理、学习等新的课题吸引着人们,因此,为计算机专业以及非计算机类专业的学生开设的 Prolog 程序设计课程愈加显得重要。本文通过对现行教材的分析、归纳,提出以下几点意见,供参考。

Ovarian Vein Thrombosis卵巢静脉血栓

Key Facts Synonyms：Gonadal vein thrombosis.Definition：Rare complication usually associated with ascending postpartum ovarian vein thrombophlebitis.Incidence：1%-2%following cesarean section complicated by endometritis;less than 0.2% following vaginal delivery.

一种改进的PrefixSpan应用层特征自动提取算法

针对基于DPI的网络流量识别中的指纹特征提取困难问题,文章提出了改进的基于Prefix Span算法的连续序列模式挖掘算法来提取应用层指纹特征。首先,改进的算法在挖掘应用层特征时加入了属性约束。其次,在进行频繁序列投影前,又引入剪枝策略。最后,通过实验表明该改进的算法在挖掘应用层指纹特征方面大大提高了效率,提取出来的特征可有效地应用于网络流量识别技术中。

热点词汇的最长时间区间查询算法

热词查询是指在一个特定的时间范围内,从文本数据中搜索热点词汇。查询一组词汇成为热词的最长时间范围是话题检测与追踪的一个重要任务。现有的热词提取算法具有较高的时间复杂度,未考虑不同偏好的用户的查询需求,难以用于热词的在线提取以及最长时间范围的在线查询。为此提出一种在线查询算法,在类别和时间的二维区间上提取热词并查询用户指定词汇成为热词的最长时间范围。该算法基于Prefix Cube技术,对传统的TF^*PDF算法加以改进,在空间复杂度不变的情况下,降低TF^*PDF算法的时间复杂度。实验表明,与传统的TF^*PDF算法相比,该算法在路透社、纽约时报和BBC三个语料库上提取热词并查询最长时间区间的运行时间减少了81%,验证了该算法的高效性。

Usage of the Word“Uncorrect”in“Politically Uncorrect”

It is not surprising that non-native speakers of English frequently make morphological errors when they are speaking or writing in English. But it is interesting to find out that some native English speakers sometimes use words in an ungrammatical or inappropriate way. This article analyses the usage of the word"uncorrect"and tries to show the background of this term by searching online and consulting to the dictionaries and also to analyze the word formation and usage of this term.

INTERCARRIER INTERFERENCE ALLEVIATION BEAMFORMING FOR OFDM WITH SPACE DIVERSITY

Orthogonal Frequency Division Multiplexing (OFDM) systems suffer from performance deterioration when the length of Cyclic Prefix (CP) is shorter than the Channel Impulse Response (CIR). The fundamental reason of this impairment is the InterCarrier Interference (ICI) and Inter- Symbol Interference (ISI) introduced by the excessive multipath delay. Specifically, Multiple Input Multiple Output (MIMO) beamforming is helpful in cancelling such interference since it can spatially suppress some of the multipath. In this paper, we propose an ICI eliminating beamforming scheme employing a per-tone processing approach, thus with moderate computational complexity. The ISI is removed by using a simple decision feedback equalizer, while the optimal steering and combining vectors are then derived to maximize the Signal to Interference plus Noise Ratio (SINR). This method not only achieves the beamforming benefit, but also significantly alleviates the ICI. Simulation results show that the proposed algorithm can effectively reduce the system Symbol Error Rate (SER), per- mitting good performance for multipath delay profiles that would break conventional links.

Reducing Cyclic Prefix Overhead Based on Symbol Repetition in NB-IoT-Based Maritime Communication

With the increasing maritime activities,a great demand of wide-area maritime digital data services is needed.Therefore,Narrowband Internet of Things(NB-IoT)that can provide wide coverage has been expected as an application for maritime communication networks(MCNS).In this paper,we aim to enhance the spectral efficiency in NB-IoT by reducing the cyclic prefix(CP)overhead in random access signal without causing interference.The key point of the proposed scheme is the symbols transmitted for multiple times repeatedly in NB-IoT.Specifically,all CP are removed and multi-path fading effect is eliminated by using a repeated symbol to cover the disturbed symbol to construct a circular convolution structure of the channel with the same effect as adding CP.In addition,a single-tap equalization is still appropriate.To validate the effectiveness of the proposed scheme,simulation results are carried out with respect to the bit error ratio(BER).

Adaptive Channel Estimation in OFDM System Using Cyclic Prefix (Kalman Filter Approach)

OFDM is a promising technique for high data rate transmission and the channel estimation is very important for implementation of OFDM. In this paper, cyclic prefix (CP) can be used as a source of channel information which is originally used to reduce inter symbol interference (ISI). Based on this CP observation, we propose two cross coupled dual Kalman filters to track the channel variations without additional training sequences. One Kalman filter AR parameter estimation and another for fading channel estimation.

序列模式挖掘在铝电解中的研究应用

序列模式挖掘是数据挖掘中的研究热点之一,它是基于关联规则的频繁项集的挖掘,其实质是在关联模型中加入时间属性。本文利用序列模式挖掘的典型算法prefix算法对铝电解中重要的工艺参数数据进行挖掘分析,给出铝电解槽的重要的工艺参数的序列化,对于提高铝电解的生产效率,节能降耗,延长率电解槽的寿命具有重要的意义。

Prefix Subsection Matching Binary Algorithm in Passive RFID System

Identifying speed,tag average response times and reliability are the most important capabilities in passive RFID(radio frequency identification) system.QT(query tree) is a famous algorithm for lowest-cost RFID tags,but its shortcoming is high searching delay and high tag average response times.A prefix subsection matching binary(PSMB) algorithm based on QTalgorithm is proposed.The key idea of PSMB anti-collision algorithm is that,during searching phase,a given reader uses the particular tags ID,which has been searched out formerly,to shorten searching delay and depress tag average response times.The idea of PSMB algorithm can be described as follows.Usually,tag ID is composed of several subsections which have different meanings.Based on the tags ID searched out formerly,a given reader builds a prefix database.In subsequent searching phase,the reader uses its prefix database to deduce searching space of tag ID.Simulation results show that identification delay of PSMB algorithm is about 1/3 of QTalgorithm,tag average response times is about 1/4 of QTalgorithm,and system throughput rate is treble QTalgorithm.

LPR-Trie: A Fast IPv6 Routing Lookup Algorithm with Virtual Nodes

The number of IPv6 routes in todays backbone routers has grown rapidly,which has put tremendous pressure on route lookup and storage.Based on the analysis of IPv6 address prefix length and distribution characteristics,this paper proposes an IPv6 route lookup architecture called LPR-Trie.The core idea of the algorithm is to utilize more spaces and accelerate routing lookup.Moreover,we put forward the concept of virtual nodes,and leverage the link between virtual nodes and ordinary nodes to accelerate routing lookup.We provide the longest prefix routing entry(LPR)calculation algorithm to achieve the longest prefix match.The experimental results show that the virtual node mechanism increases the search speed up to 244%,and the virtual nodes have better stability by setting an appropriate keep-alive time according to the characteristics of actual traffic.This paper shows that our design improves the routing lookup speed and have better memory utilization.

Scalable Multi-Hash Name Lookup Method for Named Data Networking

A Scalable Multi-Hash( SMH) name lookup method is proposed,which is based on hierarchical name decomposition to aggregate names sharing common prefixes and multiple scalable hash tables to minimize collisions among prefixes. We take the component instead of the entire name as a key in the hash functions. The SMH method achieves lookup speeds of 21. 45 and 20. 87 Mbps on prefix table with 2 million and 3. 6 million names,respectively. The proposed method is the fastest of the four methods considered and requires 61.63 and 89.17 Mb of memory on the prefix tables with 2 million and 3. 6 million names,respectively. The required memory is slightly larger than the best method. The scalability of SMH outperforms that of the other two methods.

Equivalent Time-Domain Representation and Uplink Channel Estimator for Multicarrier CDMA Systems

Many blind channel estimation methods have been proposed for direct sequence (DS) code-division multiple access (CDMA) systems, so we can certainly use them to estimate the finite impulse response (FIR) channel for the multi-carrier (MC-) CDMA system. In this paper, the MC-CDMA system is interpreted as an equivalent time-domain DS-CD-MA system with specific spreading codes. Then, an equivalently time-domain blind channel estimator is derived for the uplink MC-CDMA, which is based on second-order statistics of the received data. By exploiting singular value decomposition (SVD) and the finite alphabet property of transmitted symbols, the time-domain channel impulse response (CIR) for the uplink MC-CDMA can be accurately identified. Computer simulations illustrate both the validity and the overall performance of the proposed estimator.