基于海豚whistle信号的仿生主动声纳隐蔽探测技术研究

为解决主动声纳系统易暴露、隐蔽性差的问题,提出一种基于海豚whistle信号的仿生主动声纳隐蔽探测技术。在发射端将线性调频探测信号隐蔽在海豚whistle信号中,设计了一种主动声纳的仿生隐蔽探测信号,该信号与海洋中的海豚哨叫声十分相似,可以利用海洋中的生物环境噪声实现主动声纳的隐蔽探测。在接收端选用自适应相关器作为主动声纳的时域处理器,自适应相关器对海洋环境有较强的匹配适应能力,可以自动匹配海洋信道,有效抑制多途扩展损失,相较匹配滤波器有更高的信噪比处理增益,有助于实现远距离探测。仿真和海试结果表明,基于海豚whistle信号的仿生主动声纳隐蔽探测技术具有良好的隐蔽性和有效性。

Willingness to Whistle Blow Among Muslim Consumers

The paper reports on a qualitative study using three focus groups drawn from Muslim consumers both local and foreign. Respondents were given vignettes depicting unethical halal claims scenarios to which respondents were required to respond. Two Malaysian consumer groups responded by declaring that they will whistle blow by reporting the matter to a religious authority, the Islamic Development Department （JAKIM）, while another group that consists of six Muslim foreign students will just leave the business premise without making any complaints to any authority. The different course of actions taken could be explained by the diverse background of the Malaysian population and their level of awareness in selecting their halal food and their high degree of intolerance to such practice whilst the level of tolerance among foreign Muslim respondents might be different from their Malaysian counterparts or that they have never encountered such a problem before they came to Malaysia, The study also reports the response from JAKIM in relation to the relevant channels for whistle blowing regarding misleading halal labels.

Internal Whistle-Blowing Intentions： A Study of Demographic and Individual Factors

Internal auditors hold a unique position in their organizations to prevent, deter, and detect corporate wrongdoings. However, the role of this profession in investigating their ethical decision-making behaviors towards internal whistle-blowing intentions has been very often neglected. Furthermore, although extensive researches have been undertaken on the issue of whistle blowing globally, empirical studies on this area are still scarce in Malaysia. This paper examines internal whistle-blowing intentions among internal auditors in Malaysia by utilizing three independent vignettes. A mail survey was conducted to investigate demographic and individual factors that could influence internal auditors＇ ethical decision-making processes. The likelihood for internal whistle-blowing intentions was significant among internal auditors＇ ethical judgments for all the three vignettes. Demographic factors （gender, age, and tenure） and other individual factors （locus of control and organizational commitment） failed to explain the likelihood of internal auditors＇ internal whistle-blowing intentions. Findings should aid researchers in their understandings of the determinants of individuals＇ internal whistle-blowing behaviors.

The Anti-corruption Fights： Perescoping the Whistle Blower Policy in Nigeria

The 2015 elections and swearing of new leadership in Nigeria brought about new promises as well as new policies and strategies. The president elect, Muhammadu Buhari, was quick to indicate his intentions to fight corruption as one of the means through which the government intends to achieve good governance in Nigeria. This intention and follow-up action is like the biblical two-edged sword, cutting off sadness from the lower class while at the same time cutting off happiness from some corrupt people in government. The recent announcement of the whistle blower policy by the Federal Government as another means of fighting corruption in Nigeria brought about an increase in the discovery of hidden/looted money. Relying on primary and secondary findings, based on qualitative and quantitative data the paper examines the potency of the whistle blower policy on corruption. The puzzle： is the policy yielding positive result？ The case provides a strong case to the methodological analysis for both institutional norms to fight corruption and good governance in Nigeria. The thrust of this paper is that, the fight against corruption is a national issue that can be successfully tackled by the citizens. The paper therefore recommends that government and its citizenry come together to fight this malice called corruption.

基于差分Pattern时延差编码和海豚whistles信号的仿生水声通信技术研究

为解决传统的隐蔽水声通信方法带来的通信性能降低问题,提出了一种将差分Pattern时延差编码通信体制与海豚whistles信号相结合的仿生水声通信技术.海豚whistles信号频带较窄且各信息码元间隔不等、码元之间互相关性较弱,选取whistles信号作同步码和Pattern码,并以相邻whistles信号之间的时延差值携带信息.这种仿生的水声通信信号不易被敌方探测、截获,且差分Pattern时延差特殊的编码方式也不易使信息被破译,因此该水声通信技术具有较强的隐蔽性和保密性,且在抗码间干扰以及抗多普勒效应方面具有优异性能.本文对系统进行了水池实验,在信噪比为0 dB、存在相对运动时实现了通信速率为67 bit/s的低误码数据传输,验证了系统的有效性、稳健性和隐蔽性.

Whistle signal variations among three Indo-Pacific humpback dolphin populations in the South China Sea:a combined effect of the Qiongzhou Strait’s geographical barrier function and local ambient noise?

Geographic variations in the dolphin whistles could be useful in assessing association and isolation among populations.Whistle of free-ranging Indo-Pacific humpback dolphins(Sousa chinensis)among the Pearl River Estuary(PRE),Leizhou Bei(LZB)and Sanniang Bay(SNB)populations were investigated.A total of 2850 whistles with legible fundamental contour were extracted and 15 acoustic parameters were measured.Contrary to SNB,PRE and LZB had the same relative proportion of tonal type compositions with flat and sine representing the most frequent types.The generalized linear model analysis showed significant acoustic difference among populations and tonal types.All frequency parameters in SNB were significantly higher than those in PRE and LZB,where no significant variation was observed in most of the parameters either at the population level or within each tonal type.Canonical discriminant functions analysis showed a smaller difference between PRE and LZB than between PRE and SNB and between LZB and SNB.Compared with previous recordings,recent recordings demonstrated a consistent pattern of becoming higher in whistle frequency parameters in both LZB and SNB populations,suggesting that noise pollution in LZB and SNB increasing with time according to the acoustic niche hypothesis.Dolphin whistle’s geographic variations could be shaped by the combined function of the geographical barrier function of the Qiongzhou strait and local ambient noise.Considering the isolated condition and the relatively smaller population size of the humpback dolphin in the SNB,more effective and proactive conservation actions should be taken to prevent the extinction of small populations.

A method for classifying whistles of bottlenose dolphin(Tursiops truncates) based on syntactic pattern reorganization

A method based on syntactic pattern recognition was presented to automatically classify whistles of bottlenose dolphin. Dolphin whistles have typically been characterized in terms of their instantaneous frequency as a function of time, which is also known as ＂whistle contour＂. The frequency variation features of a whistle were extracted according to its contour. Then, the frequency variation features were used for learning grammatical patterns. A whistle was classified according to grammatical pattern of its frequency variation features. The exper- imental results showed that the classification accuracy of the proposed method was 95%. The method can provide technical support for acoustic study of dolphins＇ biological behavior.

Titanic Whistles Blown 87 Years After Sinking

【选注者言:春节的爆竹声,连绵不断,甚至延续到半夜,到凌晨。我失眠了,但心情却并不坏。爆竹一声除旧,桃符万户更新!现在是凌晨两点,英语称之为small hours,我披衣起身,打开电脑,在网上浏览起来。读到一篇短文,令我精神抖擞,睡意全消。泰坦尼克巨轮已经沉没87个寒暑了,人们还在银幕上演绎她的故事,观者垂泪;人们还在聆听她的汽笛声,听众伤感。我是一个英语教师,细品本文,觉得本文造句非常讲究,用的大多是“拖泥带水”的长句,作者很懂修辞,这种“欲休还说”的句式不是很好地衬托渲染了今人怀旧时的那种缠绵悱恻的心绪吗?比如下句就很典型,我读之再三: When they were made the whistles weighed 750 pounds(340 kg)and could be heard more than 10 miles(16 km)away, according to the St. Paul Convention and Visitors Bureau, which hosted Saturday's event. 编辑先生,读者同志,不知你们是否同意我的以上分析。如果你们不同意,那么,是不是我过于善感了?】

基于Elmo数字伺服控制器的机载吊舱陀螺稳定平台设计

为了解决传统模拟式机载吊舱陀螺稳定平台稳定性能提升有限的问题,设计了一个数字化的陀螺稳定平台。该平台采用Whistle系列数字伺服控制器。在研究机载陀螺稳定平台原理和Elmo Whistle控制器的结构与使用方法的基础上,以Whistle系列控制器5/100型号为主要控制器,设计了具有陀螺稳定、吊舱运动控制、LOCK信号、限位信号等功能的机载陀螺稳定平台。通过Elmo Studio软件平台,编写相应的功能程序,最终实现机载吊舱陀螺稳定的功能。另外,该稳定平台通过串口RS232通信,用指令控制吊舱运动,取得了良好的控制效果。该稳定平台已应用于现有吊舱,稳定性能提升到50μrad。

圈养瓶鼻海豚通信信号声谱特征及声行为研究

对2只圈养瓶鼻海豚的通信信号进行采集,通过Matlab进行短时傅里叶变换生成声谱图,根据频率阈值提取信号基频轮廓,计算其起始频率、结束频率、最大频率、最小频率、持续时间、拐点数的均值及标准偏差,采用双尾t检验分析2只海豚声谱特征的差异性,并将信号类型与行为进行匹配分析。结果表明,2只海豚的发声类型与声谱特征均存在差异:发声类型主要以固定型为主,3号发出上扫型与正弦型的比例更高;声谱特征在持续时间、最小频率处存在显著差异(p<0.05)。在行为方面,信号类型与行为存在关联:跃出水面时,主要发出固定型信号,在栅栏处停留时,主要发出凸型信号,推测固定型信号是跃出水面的标志声音,凸型是与同伴交流的标志声音。

明喻修辞格的运用及其翻译——以短篇小说《寒笛》为例

明喻修辞格是英汉两种语言中常用的修辞手法,能使文章语言更加生动形象。该文以短篇小说《寒笛》(The Whistle)为例,通过比较原文中的明喻实例及其译文,探析英译汉中如何更好地实现该修辞格在两种语言间的转换。

GIS Based Approach to Determine the Changes of Water Hyacinth (Eichhornia crassipes) Cover and Relation with Lesser Whistling Teal (Dendrocygna javanica) Assemblage at Santragachi Wetland, West Bengal

The present investigation is conducted to study the year wise (2011to 2018) changes of water hyacinth (Eichhornia crassipes) cover atSantragachi Lake a Wetland under National Wetland ConservationProgramme of India. Further the relationship between water hyacinthcover and the most abundant migratory waterbirds of Satragachi, LesserWhistling Teal (LWT;Dendrocygna javanica) is assessed because this birdspecies is prefer depending on water hyacinth mat for their roosting. Thestudy comprises of eight satellite images procured from Google earth (2011to 2018) to explore this relationship. A marked decline in the number ofLWT at Santragachi wetland is observed in the year of 2017 and 2018. Itis very interesting fact that from 2017-2018, the water hyacinth mat of thiswetland is almost cleared before winter and the result of cluster analysissupports this fact. Significant positive correlation is also observed withinLWT number and water hyacinth cover area (r = 0.7481 at p< 0.05) alongwith the total perimeter (r = 0.8648 at p< 0.05) of the water hyacinthislands at Santragachi wetland. However, open water area is also neededfor diving, swimming, food searching for the LWT and other waterbirds.Therefore, more study is needed to optimize the clearing operations,focused on optimizing the shape and size of water hyacinth islands forproper management of the waterbirds habitat.

Whistling Arrows in Gongbo

Some 1,500 years ago, people in the Gongbo area invented whistling arrows to enliven their celebration of bumper harvests and major events.Today, China lists shooting whistling arrows among ethnic minority sports events.Arrow, Bow and TargetThe whistling arrow is 0.6 meter long and is topped with a wooden head that is hollow. Square at the arrowbead,

Disturbance identification of electric field data observed by the CSES-01 satellite before earthquakes

Numerous studies have confirmed that electromagnetic disturbances before earthquakes can be observed by satellites.In this study,we use the C-value method that includes the acoustic whistle signature;pre-seismic ionospheric electromagnetic disturbance signals were acquired based on the CSES-01 satellite electric field data,and the maximum value of C in the earthquake preparation zones increased continuously from 2.0 three days before the earthquake and reached a maximum weight of 3.0 on the day of the earthquake,after the earthquake,it gradually decreased and recovered to about 2.0;its the C values fluctuated between-2 and 3,it is different from the C values range-2–12 of the previous seismic case study using the DEMETER satellite,which may be related to the orbital altitude and revisit period of the satellite.Then,the C values were normalized,and the time series analysis of the obtained θ values were done,and the results showed that:In the pregnant zone,the background variation of the disturbance amplitude θ is within 2σ,and the maximum disturbance amplitude of θ starts to increase gradually from the seventh period(one period of 5 days,i.e.,35–39 days before the earthquake),it reached 2σ by the fourth preseismic cycle(20–24 days before the earthquake),and then dropped sharply to about 1.5σ in the third pre-seismic cycle(15–19days before the earthquake),after two cycles of increase,the θ over the epicenter reached a maximum of 2.1σ at the time of the earthquake(combining the time of the earthquake and the satellite flight characteristics,the epicenter period is defined as January25-January 29,2020,and this defines the study time period line),and the θ decreases to within 2 times the standard range after the earthquake;The negative value of the disturbance amplitude θ in the central region of the pregnant seismic zone during the earthquake shows the transient energy release process.Through comparison,the θ values obtained by normalization based on the C-value method takes into account the variation of the background field,and the result can better reflect the energy change of the ionospheric field before the earthquakes.

An improved Merkle hash tree based secure scheme for bionic underwater acoustic communication

Recently,bionic signals have been used to achieve covert underwater acoustic communication(UWAC)with high signal-to-noise ratios(SNRs)over transmission systems.A high SNR allows the attackers to proceed with their mischievous goals and makes transmission systems vulnerable against malicious attacks.In this paper we propose an improved Merkle hash tree based secure scheme that can resist current underwater attacks,i.e.,replay attack,fabricated message attack,message-altering attack,and analyst attack.Security analysis is performed to prove that the proposed scheme can resist these types of attacks.Performance evaluations show that the proposed scheme can meet UWAC limitations due to its efficiency regarding energy consumption,communication overhead,and computation cost.