An agonistic display by a white shark was observed and photographed during a cage dive at Guadalupe Island in November 2015. Exhibiting exaggerated pectoral fin depression, agonistic behaviors have been previously obs...An agonistic display by a white shark was observed and photographed during a cage dive at Guadalupe Island in November 2015. Exhibiting exaggerated pectoral fin depression, agonistic behaviors have been previously observed and described in several shark species. This account may be the first record of a white shark in close proximity to a caged diver, exhibiting strong pectoral fin depression significantly dipped, in the mid-agonistic display. Such displays should be considered as aggressive and potentially life-threatening by those using the ocean for recreational or professional purposes.展开更多
Feeding is the likely cause for tooth shedding in sharks. Although the overall process of loosing teeth has been well studied, hardly any emphasis has been given to the actual separation mechanism between a shark’s t...Feeding is the likely cause for tooth shedding in sharks. Although the overall process of loosing teeth has been well studied, hardly any emphasis has been given to the actual separation mechanism between a shark’s tooth base and the surrounding jaw tissue. Attention is given to this very process, in connection to a never before videotaped tooth loss of a white shark, Carcharodon carcharias, that occurred within 0.3 seconds. Since the shark did not bite into anything prior to this observation, the cause for this tooth loss does not seem feeding but fatigue related, triggered through a combination of mechanical and potentially biochemical degradation processes.展开更多
Flash Crowd attacks are a form of Distributed Denial of Service(DDoS)attack that is becoming increasingly difficult to detect due to its ability to imitate normal user behavior in Cloud Computing(CC).Botnets are often...Flash Crowd attacks are a form of Distributed Denial of Service(DDoS)attack that is becoming increasingly difficult to detect due to its ability to imitate normal user behavior in Cloud Computing(CC).Botnets are often used by attackers to perform a wide range of DDoS attacks.With advancements in technology,bots are now able to simulate DDoS attacks as flash crowd events,making them difficult to detect.When it comes to application layer DDoS attacks,the Flash Crowd attack that occurs during a Flash Event is viewed as the most intricate issue.This is mainly because it can imitate typical user behavior,leading to a substantial influx of requests that can overwhelm the server by consuming either its network bandwidth or resources.Therefore,identifying these types of attacks on web servers has become crucial,particularly in the CC.In this article,an efficient intrusion detection method is proposed based on White Shark Optimizer and ensemble classifier(Convolutional Neural Network(CNN)and LighGBM).Experiments were conducted using a CICIDS 2017 dataset to evaluate the performance of the proposed method in real-life situations.The proposed IDS achieved superior results,with 95.84%accuracy,96.15%precision,95.54%recall,and 95.84%F1 measure.Flash crowd attacks are challenging to detect,but the proposed IDS has proven its effectiveness in identifying such attacks in CC and holds potential for future improvement.展开更多
Online reviews regarding purchasing services or products offered are the main source of users’opinions.To gain fame or profit,generally,spam reviews are written to demote or promote certain targeted products or servi...Online reviews regarding purchasing services or products offered are the main source of users’opinions.To gain fame or profit,generally,spam reviews are written to demote or promote certain targeted products or services.This practice is called review spamming.During the last few years,various techniques have been recommended to solve the problem of spam reviews.Previous spam detection study focuses on English reviews,with a lesser interest in other languages.Spam review detection in Arabic online sources is an innovative topic despite the vast amount of data produced.Thus,this study develops an Automated Spam Review Detection using optimal Stacked Gated Recurrent Unit(SRD-OSGRU)on Arabic Opinion Text.The presented SRD-OSGRU model mainly intends to classify Arabic reviews into two classes:spam and truthful.Initially,the presented SRD-OSGRU model follows different levels of data preprocessing to convert the actual review data into a compatible format.Next,unigram and bigram feature extractors are utilized.The SGRU model is employed in this study to identify and classify Arabic spam reviews.Since the trial-and-error adjustment of hyperparameters is a tedious process,a white shark optimizer(WSO)is utilized,boosting the detection efficiency of the SGRU model.The experimental validation of the SRD-OSGRU model is assessed under two datasets,namely DOSC dataset.An extensive comparison study pointed out the enhanced performance of the SRD-OSGRU model over other recent approaches.展开更多
随着海洋石油开采的不断深入,海洋石油固定平台作为重要的生产设施,对安全性和可靠性的需求日益增加。应急电源作为固定平台的重要组成部分,在应对突发事件和断电情况时提供电力支持方面具有至关重要的作用。因此,针对海洋石油固定平台...随着海洋石油开采的不断深入,海洋石油固定平台作为重要的生产设施,对安全性和可靠性的需求日益增加。应急电源作为固定平台的重要组成部分,在应对突发事件和断电情况时提供电力支持方面具有至关重要的作用。因此,针对海洋石油固定平台应急电源的设计问题进行深入研究和分析。通过介绍海洋石油固定平台的特点,分析现有海洋石油固定平台应急电源的设计方案及其优缺点,结合实际需求提出一种基于多目标白鲨优化(Multi-Objective White Shark Optimizer,MOWSO)算法的柴油发电机组与储能系统相结合的方案。经过实验模拟和数据分析,该方案具备较高的可靠性和稳定性,能够满足海洋石油固定平台关键设备的电力需求。展开更多
The purpose of legislation like the Endangered Species Act is to provide a means to conserve the ecosystems of endangered and threatened species, but not all species that may appear to need conservation are granted pr...The purpose of legislation like the Endangered Species Act is to provide a means to conserve the ecosystems of endangered and threatened species, but not all species that may appear to need conservation are granted protection. An estimated 100 million sharks are killed each year largely due to exploitation, yet few shark species are ever granted protection under state or federal endangered species acts. The Northeastern Pacific population of the Great White Shark is no exception. Despite the numerous threats facing the white shark, NOAA denied a petition to list it as an endangered or threatened species under the federal Endangered Species Act. In light of the pending California decision to list the white shark under its state endangered species act, this paper considers whether or not such extreme protections are necessary. This paper first discusses the threats facing the white shark, the listing processes of both the federal and the California endangered species acts, and NOAA’s 12-month negative finding. Finally, this paper concludes that endangered species protections are not warranted in the case of the Northeastern Pacific white shark because of prior government intervention and conservation efforts already in place.展开更多
文摘An agonistic display by a white shark was observed and photographed during a cage dive at Guadalupe Island in November 2015. Exhibiting exaggerated pectoral fin depression, agonistic behaviors have been previously observed and described in several shark species. This account may be the first record of a white shark in close proximity to a caged diver, exhibiting strong pectoral fin depression significantly dipped, in the mid-agonistic display. Such displays should be considered as aggressive and potentially life-threatening by those using the ocean for recreational or professional purposes.
文摘Feeding is the likely cause for tooth shedding in sharks. Although the overall process of loosing teeth has been well studied, hardly any emphasis has been given to the actual separation mechanism between a shark’s tooth base and the surrounding jaw tissue. Attention is given to this very process, in connection to a never before videotaped tooth loss of a white shark, Carcharodon carcharias, that occurred within 0.3 seconds. Since the shark did not bite into anything prior to this observation, the cause for this tooth loss does not seem feeding but fatigue related, triggered through a combination of mechanical and potentially biochemical degradation processes.
基金The authors gratefully acknowledge the approval and the support of this research study by grant no.SCIA-2022-11-1551 from the Deanship of Scientific Research at Northern Border University,Arar,K.S.A.
文摘Flash Crowd attacks are a form of Distributed Denial of Service(DDoS)attack that is becoming increasingly difficult to detect due to its ability to imitate normal user behavior in Cloud Computing(CC).Botnets are often used by attackers to perform a wide range of DDoS attacks.With advancements in technology,bots are now able to simulate DDoS attacks as flash crowd events,making them difficult to detect.When it comes to application layer DDoS attacks,the Flash Crowd attack that occurs during a Flash Event is viewed as the most intricate issue.This is mainly because it can imitate typical user behavior,leading to a substantial influx of requests that can overwhelm the server by consuming either its network bandwidth or resources.Therefore,identifying these types of attacks on web servers has become crucial,particularly in the CC.In this article,an efficient intrusion detection method is proposed based on White Shark Optimizer and ensemble classifier(Convolutional Neural Network(CNN)and LighGBM).Experiments were conducted using a CICIDS 2017 dataset to evaluate the performance of the proposed method in real-life situations.The proposed IDS achieved superior results,with 95.84%accuracy,96.15%precision,95.54%recall,and 95.84%F1 measure.Flash crowd attacks are challenging to detect,but the proposed IDS has proven its effectiveness in identifying such attacks in CC and holds potential for future improvement.
基金Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2022R263)PrincessNourah bint Abdulrahman University,Riyadh,Saudi Arabia.The authors would like to thank the Deanship of Scientific Research at Umm Al-Qura University for supporting this work by Grant Code:22UQU4310373DSR58The authors are thankful to the Deanship of ScientificResearch atNajranUniversity for funding thiswork under theResearch Groups Funding program grant code(NU/RG/SERC/11/7).
文摘Online reviews regarding purchasing services or products offered are the main source of users’opinions.To gain fame or profit,generally,spam reviews are written to demote or promote certain targeted products or services.This practice is called review spamming.During the last few years,various techniques have been recommended to solve the problem of spam reviews.Previous spam detection study focuses on English reviews,with a lesser interest in other languages.Spam review detection in Arabic online sources is an innovative topic despite the vast amount of data produced.Thus,this study develops an Automated Spam Review Detection using optimal Stacked Gated Recurrent Unit(SRD-OSGRU)on Arabic Opinion Text.The presented SRD-OSGRU model mainly intends to classify Arabic reviews into two classes:spam and truthful.Initially,the presented SRD-OSGRU model follows different levels of data preprocessing to convert the actual review data into a compatible format.Next,unigram and bigram feature extractors are utilized.The SGRU model is employed in this study to identify and classify Arabic spam reviews.Since the trial-and-error adjustment of hyperparameters is a tedious process,a white shark optimizer(WSO)is utilized,boosting the detection efficiency of the SGRU model.The experimental validation of the SRD-OSGRU model is assessed under two datasets,namely DOSC dataset.An extensive comparison study pointed out the enhanced performance of the SRD-OSGRU model over other recent approaches.
文摘随着海洋石油开采的不断深入,海洋石油固定平台作为重要的生产设施,对安全性和可靠性的需求日益增加。应急电源作为固定平台的重要组成部分,在应对突发事件和断电情况时提供电力支持方面具有至关重要的作用。因此,针对海洋石油固定平台应急电源的设计问题进行深入研究和分析。通过介绍海洋石油固定平台的特点,分析现有海洋石油固定平台应急电源的设计方案及其优缺点,结合实际需求提出一种基于多目标白鲨优化(Multi-Objective White Shark Optimizer,MOWSO)算法的柴油发电机组与储能系统相结合的方案。经过实验模拟和数据分析,该方案具备较高的可靠性和稳定性,能够满足海洋石油固定平台关键设备的电力需求。
文摘The purpose of legislation like the Endangered Species Act is to provide a means to conserve the ecosystems of endangered and threatened species, but not all species that may appear to need conservation are granted protection. An estimated 100 million sharks are killed each year largely due to exploitation, yet few shark species are ever granted protection under state or federal endangered species acts. The Northeastern Pacific population of the Great White Shark is no exception. Despite the numerous threats facing the white shark, NOAA denied a petition to list it as an endangered or threatened species under the federal Endangered Species Act. In light of the pending California decision to list the white shark under its state endangered species act, this paper considers whether or not such extreme protections are necessary. This paper first discusses the threats facing the white shark, the listing processes of both the federal and the California endangered species acts, and NOAA’s 12-month negative finding. Finally, this paper concludes that endangered species protections are not warranted in the case of the Northeastern Pacific white shark because of prior government intervention and conservation efforts already in place.
