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 we...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.展开更多
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 toward...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.展开更多
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 corr...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.展开更多
This paper deeply discusses the causes of gear howling noise,the identification and analysis of multi-source excitation,the transmission path of dynamic noise,simulation and experimental research,case analysis,optimiz...This paper deeply discusses the causes of gear howling noise,the identification and analysis of multi-source excitation,the transmission path of dynamic noise,simulation and experimental research,case analysis,optimization effect,etc.,aiming to better provide a certain guideline and reference for relevant researchers.展开更多
Accurate estimations of animal population size are pivotal for implementing management strategies properly.Recapture technique based on sounds as a specimen identifcation mark has barely been used for marine mammals.H...Accurate estimations of animal population size are pivotal for implementing management strategies properly.Recapture technique based on sounds as a specimen identifcation mark has barely been used for marine mammals.However,inferring abundance estimates from acoustic methods could enhance the accuracy and precision of population size assessments.Here,we tested the possibility of using signature whistles as individual marks for estimating the size of common bottlenose dolphin(Tursiops truncatus)populations.Data were continuously collected for 326 days in 2015–2016,by using a fxed acoustic device located in the Sicily Strait(Italy).The SIGID method was applied to identify Signature Whistles Types(SWTs)over 7,000 h of recordings.Eighty SWTs were detected as long as their stereotyped fundamental frequency contours were repeated in bouts of at least 6 renditions.The mean SWTs monthly recording rate resulted in 0.19(Standard deviation=0.16),with 20 SWTs recorded over 5 or more different encounters(until a maximum of 30 encounters).The Jolly–Seber model(with POPAN formulation)was run in Mark software to estimate the population size.The estimated population size resulted in 171 bottlenose dolphins(95%confdence interval=137–215).Even if the detection and identifcation of signature whistles required crucial precautions,and animals could be detected differently from visual techniques,the population size estimate obtained was comparable with previous results based on physical marks data.These outcomes demonstrated that signature whistles can be considered a strongly effective tool for integrating traditional mark-recapture techniques with fnely estimated dolphins’population abundances.展开更多
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 Estua...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.展开更多
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...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.展开更多
【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。...【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?】展开更多
With the development of the automobile industry, the popularization of vehicles and the improvement of people's living standards, consumers are paying more and more attention to the NVH performance of the vehicle ...With the development of the automobile industry, the popularization of vehicles and the improvement of people's living standards, consumers are paying more and more attention to the NVH performance of the vehicle while pursuing vehicle safety, functional configuration and reliability. As one of the important factors of vehicle NVH, braking NVH directly affects the performance of vehicle NVH and also affects the car brand image. Due to the complexity of the causes of braking NVH, it involves many disciplines such as tribology, vibration mechanics, materials science and computer simulation. Therefore, braking NVH has become a common problem in various OEMs. The problem of braking NVH seriously affects the driving quality of vehicles. Therefore, various OEMs pay more and more attention to braking NVH. At present, domestic OEMs are committed to improving the bench matching procedure, hoping to find a brake NVH with excellent performance through bench matching. Through the long-term data collection of braking NVH working conditions of various models, the characteristics of the main working conditions of braking NVH in the current market are mastered, and the standard procedures of SAE J2521 are compared and analyzed. Chinese market demand. At the same time, the test requirements and evaluation methods of bench matching are described in detail. Ensure that reliable solutions can be found quickly and efficiently during new model development and problem resolution.展开更多
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. Fu...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.展开更多
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 even...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,展开更多
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 ionos...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.展开更多
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 mis...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.展开更多
文摘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.
文摘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.
文摘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.
文摘This paper deeply discusses the causes of gear howling noise,the identification and analysis of multi-source excitation,the transmission path of dynamic noise,simulation and experimental research,case analysis,optimization effect,etc.,aiming to better provide a certain guideline and reference for relevant researchers.
基金the project“BIOforIU project PONa3_00025-Multidisciplinary Infrastructure for the Study and Development of Marine and Terrestrial Biodiversity in the Perspective of Innovation Union.”Part of the analysis was funded under the National Recovery and Resilience Plan(NRRP),Mission 4 Component 2 Investment 1.4-Call for tender No.3138 of 16 December 2021,rectifed by Decree n.3175 of 18 December 2021 of Italian Ministry of University and Research funded by the European Union-NextGenerationEU,Award Number:Project code CN_00000033,Concession Decree No.1034 of 17 June 2022 adopted by the Italian Ministry of University and Research,Project title"National Biodiversity Future Center-NBFC".
文摘Accurate estimations of animal population size are pivotal for implementing management strategies properly.Recapture technique based on sounds as a specimen identifcation mark has barely been used for marine mammals.However,inferring abundance estimates from acoustic methods could enhance the accuracy and precision of population size assessments.Here,we tested the possibility of using signature whistles as individual marks for estimating the size of common bottlenose dolphin(Tursiops truncatus)populations.Data were continuously collected for 326 days in 2015–2016,by using a fxed acoustic device located in the Sicily Strait(Italy).The SIGID method was applied to identify Signature Whistles Types(SWTs)over 7,000 h of recordings.Eighty SWTs were detected as long as their stereotyped fundamental frequency contours were repeated in bouts of at least 6 renditions.The mean SWTs monthly recording rate resulted in 0.19(Standard deviation=0.16),with 20 SWTs recorded over 5 or more different encounters(until a maximum of 30 encounters).The Jolly–Seber model(with POPAN formulation)was run in Mark software to estimate the population size.The estimated population size resulted in 171 bottlenose dolphins(95%confdence interval=137–215).Even if the detection and identifcation of signature whistles required crucial precautions,and animals could be detected differently from visual techniques,the population size estimate obtained was comparable with previous results based on physical marks data.These outcomes demonstrated that signature whistles can be considered a strongly effective tool for integrating traditional mark-recapture techniques with fnely estimated dolphins’population abundances.
基金This research was supported by grants from the National Natural Science Foundation of China(Grant No.41806197)Ocean Park Conservation Foundation of Hong Kong(AW011920)Chinese white dolphin monitoring program of Guangzhou harbor deepwater navigation channel widening project(Grant No.HTYXJC)to Zhitao Wang.
文摘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.
文摘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.
文摘【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?】
文摘With the development of the automobile industry, the popularization of vehicles and the improvement of people's living standards, consumers are paying more and more attention to the NVH performance of the vehicle while pursuing vehicle safety, functional configuration and reliability. As one of the important factors of vehicle NVH, braking NVH directly affects the performance of vehicle NVH and also affects the car brand image. Due to the complexity of the causes of braking NVH, it involves many disciplines such as tribology, vibration mechanics, materials science and computer simulation. Therefore, braking NVH has become a common problem in various OEMs. The problem of braking NVH seriously affects the driving quality of vehicles. Therefore, various OEMs pay more and more attention to braking NVH. At present, domestic OEMs are committed to improving the bench matching procedure, hoping to find a brake NVH with excellent performance through bench matching. Through the long-term data collection of braking NVH working conditions of various models, the characteristics of the main working conditions of braking NVH in the current market are mastered, and the standard procedures of SAE J2521 are compared and analyzed. Chinese market demand. At the same time, the test requirements and evaluation methods of bench matching are described in detail. Ensure that reliable solutions can be found quickly and efficiently during new model development and problem resolution.
文摘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.
文摘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,
基金supported by the National Natural Science Foundation of China (Grant No. 42104159)the APSCO Earthquake Project (Phase Ⅱ)+1 种基金ISSI-BJ International Team (Grant No. 2019-33)Dragon 5 Cooperation Proposal (Grant No. #59308)。
文摘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.
文摘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.
