• Title/Summary/Keyword: detection technique

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An Analysis of Optimal Sequences for the Detection of Wake-up Signal in Disaster-preventing Broadcast (재난방송용 대기모드 해제신호 검출을 위한 최적 부호 성능 분석)

  • Park, Hae Yong;Jo, Bonggyun;Kim, Heung Mook;Han, Dong Seog
    • Journal of Broadcast Engineering
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    • v.19 no.4
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    • pp.491-501
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    • 2014
  • Recently, the need for disaster-preventing broadcast has increased gradually to cope with natural disaster like earthquake and tsunami causing enormous losses of both life and property. In disaster-preventing broadcast system, the wake-up signal is used to alert user terminal and switch the current state of channel to the emergency channel, which is for the fast and efficient delivery of emergency information. In this paper, we propose the detection method of wake-up signal for disaster-preventing broadcast systems. The wake-up signals for disaster-preventing broadcast should have a good auto-correlation property in low power and narrow-band conditions that does not affect the existing digital television (DTV) system. The suitability of the m-sequence and complementary code (CC) is analyzed for wake-up signals according to signal to noise ratio. A wake-up signal is proposed by combining the direct sequence spread spectrum (DSSS) technique and pseudo noise (PN) sequences such as Barker and Walsh-Hadamard codes. By using the proposed method, a higher detecting performance can be achieved by the spreading gain compared to the single long m-sequence and the Golay code.

Real-time Hand Region Detection and Tracking using Depth Information (깊이정보를 이용한 실시간 손 영역 검출 및 추적)

  • Joo, SungIl;Weon, SunHee;Choi, HyungIl
    • KIPS Transactions on Software and Data Engineering
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    • v.1 no.3
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    • pp.177-186
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    • 2012
  • In this paper, we propose a real-time approach for detecting and tracking a hand region by analyzing depth images. We build a hand model in advance. The model has the shape information of a hand. The detecting process extracts out moving areas in an image, which are possibly caused by moving a hand in front of a camera. The moving areas can be identified by analyzing accumulated difference images and applying the region growing technique. The extracted moving areas are compared against a hand model to get justified as a hand region. The tracking process keeps the track of center points of hand regions of successive frames. For this purpose, it involves three steps. The first step is to determine a seed point that is the closest point to the center point of a previous frame. The second step is to perform region growing to form a candidate region of a hand. The third step is to determine the center point of a hand to be tracked. This point is searched by the mean-shift algorithm within a confined area whose size varies adaptively according to the depth information. To verify the effectiveness of our approach, we have evaluated the performance of our approach while changing the shape and position of a hand as well as the velocity of hand movement.

Development of Automatic Cluster Algorithm for Microcalcification in Digital Mammography (디지털 유방영상에서 미세석회화의 자동군집화 기법 개발)

  • Choi, Seok-Yoon;Kim, Chang-Soo
    • Journal of radiological science and technology
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    • v.32 no.1
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    • pp.45-52
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    • 2009
  • Digital Mammography is an efficient imaging technique for the detection and diagnosis of breast pathological disorders. Six mammographic criteria such as number of cluster, number, size, extent and morphologic shape of microcalcification, and presence of mass, were reviewed and correlation with pathologic diagnosis were evaluated. It is very important to find breast cancer early when treatment can reduce deaths from breast cancer and breast incision. In screening breast cancer, mammography is typically used to view the internal organization. Clusterig microcalcifications on mammography represent an important feature of breast mass, especially that of intraductal carcinoma. Because microcalcification has high correlation with breast cancer, a cluster of a microcalcification can be very helpful for the clinical doctor to predict breast cancer. For this study, three steps of quantitative evaluation are proposed : DoG filter, adaptive thresholding, Expectation maximization. Through the proposed algorithm, each cluster in the distribution of microcalcification was able to measure the number calcification and length of cluster also can be used to automatically diagnose breast cancer as indicators of the primary diagnosis.

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Evaluation of bone quality in alveolar crest obscured by dental implants ; A pilot study by densitometric digital analysis in mandibular bone specimen (치과 임플란트 주변 협설측 치조골의 변화분석 - 하악골 시편에서의 디지털 농도분석법을 이용한 실험적 고찰 -)

  • Kwon, Kung-Rock
    • The Journal of Korean Academy of Prosthodontics
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    • v.36 no.6
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    • pp.900-913
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    • 1998
  • Despite of technical difficulties, the combination of occlusal projection and densitometric digital analysis may ultimately provide a means of detection of subtle bone loss at the facial and lingual side of dental implant (Oblique occlusal view is more useful for $ITI^{(R)}$ dental implant due to its contour of shoulder as like tulip flower). In this study, conventional periapical projections of x-ray beam had shown more high sensitivity to detect the bony defects than oblique occlusal projections in alveolar crest obscured by dental implants or not, even if the difference was not statistically significant. Unlike conventional periapical projections. occusal projections combined with densitometric digital analysis technique may provide a means for detection of subtle bone change at the all around of implants without obscuring effect by implant itself. Although the results from this in vitro study were performed under limited circumstances, these results might afford more possibility and versatile modality of diagnosis options to clinician in the implant practice.

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Research on text mining based malware analysis technology using string information (문자열 정보를 활용한 텍스트 마이닝 기반 악성코드 분석 기술 연구)

  • Ha, Ji-hee;Lee, Tae-jin
    • Journal of Internet Computing and Services
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    • v.21 no.1
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    • pp.45-55
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    • 2020
  • Due to the development of information and communication technology, the number of new / variant malicious codes is increasing rapidly every year, and various types of malicious codes are spreading due to the development of Internet of things and cloud computing technology. In this paper, we propose a malware analysis method based on string information that can be used regardless of operating system environment and represents library call information related to malicious behavior. Attackers can easily create malware using existing code or by using automated authoring tools, and the generated malware operates in a similar way to existing malware. Since most of the strings that can be extracted from malicious code are composed of information closely related to malicious behavior, it is processed by weighting data features using text mining based method to extract them as effective features for malware analysis. Based on the processed data, a model is constructed using various machine learning algorithms to perform experiments on detection of malicious status and classification of malicious groups. Data has been compared and verified against all files used on Windows and Linux operating systems. The accuracy of malicious detection is about 93.5%, the accuracy of group classification is about 90%. The proposed technique has a wide range of applications because it is relatively simple, fast, and operating system independent as a single model because it is not necessary to build a model for each group when classifying malicious groups. In addition, since the string information is extracted through static analysis, it can be processed faster than the analysis method that directly executes the code.

Endoscopic Findings in a Mass Screening Program for Gastric Cancer in a High Risk Region - Guilan Province of Iran

  • Mansour-Ghanaei, Fariborz;Sokhanvar, Homayoon;Joukar, Farahnaz;Shafaghi, Afshin;Yousefi-Mashhour, Mahmud;Valeshabad, Ali Kord;Fakhrieh, Saba;Aminian, Keyvan;Ghorbani, Kambiz;Taherzadeh, Zahra;Sheykhian, Mohammad Reza;Rajpout, Yaghoub;Mehrvarz, Alireza
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1407-1412
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    • 2012
  • Background & Objectives: Gastric cancer is a leading cause of cancer-related deaths in both sexes in Iran. This study was designed to assess upper GI endoscopic findings among people > 50 years targeted in a mass screening program in a hot-point region. Methods: Based on the pilot results in Guilan Cancer Registry study (GCRS), one of the high point regions for GC-Lashtenesha- was selected. The target population was called mainly using two methods: in rural regions, by house-house direct referral and in urban areas using public media. Upper GI endoscopy was performed by trained endoscopists. All participants underwent biopsies for rapid urea test (RUT) from the antrum and also further biopsies from five defined points of stomach for detection of precancerous lesions. In cases of visible gross lesions, more diagnostic biopsies were taken and submitted for histopathologic evaluation. Results: Of 1,394 initial participants, finally 1,382 persons (702 women, 680 men) with a mean age of $61.7{\pm}9.0$ years (range: 50-87 years) underwent upper GI endoscopy. H. pylori infection based on the RUT was positive in 66.6%. Gastric adenocarcinoma and squamous cell carcinoma of esophagus were detected in seven (0.5%) and one (0.07%) persons, respectively. A remarkable proportion of studied participants were found to have esophageal hiatal hernia (38.4%). Asymptomatic gastric masses found in 1.1% (15) of cases which were mostly located in antrum (33.3%), cardia (20.0%) and prepyloric area (20.0%). Gastric and duodenal ulcers were found in 5.9% (82) and 6.9% (96) of the screened population. Conclusion: Upper endoscopy screening is an effective technique for early detection of GC especially in high risk populations. Further studies are required to evaluate cost effectiveness, cost benefit and mortality and morbidity of this method among high and moderate risk population before recommending this method for the GC surveillance program at the national level.

Sensor Fault Detection Scheme based on Deep Learning and Support Vector Machine (딥 러닝 및 서포트 벡터 머신기반 센서 고장 검출 기법)

  • Yang, Jae-Wan;Lee, Young-Doo;Koo, In-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.2
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    • pp.185-195
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    • 2018
  • As machines have been automated in the field of industries in recent years, it is a paramount importance to manage and maintain the automation machines. When a fault occurs in sensors attached to the machine, the machine may malfunction and further, a huge damage will be caused in the process line. To prevent the situation, the fault of sensors should be monitored, diagnosed and classified in a proper way. In the paper, we propose a sensor fault detection scheme based on SVM and CNN to detect and classify typical sensor errors such as erratic, drift, hard-over, spike, and stuck faults. Time-domain statistical features are utilized for the learning and testing in the proposed scheme, and the genetic algorithm is utilized to select the subset of optimal features. To classify multiple sensor faults, a multi-layer SVM is utilized, and ensemble technique is used for CNN. As a result, the SVM that utilizes a subset of features selected by the genetic algorithm provides better performance than the SVM that utilizes all the features. However, the performance of CNN is superior to that of the SVM.

Reliability Improvement of the Electronic Security Fence Using Friction Electricity Sensor by Analyzing Frequency Characteristic of Environmental Noise Signal (환경잡음신호의 주파수특성 분석에 의한 전자보안펜스의 신뢰성 향상)

  • Yun, Seok Jin;Won, Seo Yeon;Kim, Hie Sik;Lee, Young Chul;Jang, Woo Young
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.3
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    • pp.173-180
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    • 2015
  • A passive type of fence security system was developed, which was based on electric charge detection technique. The implemented fence security system was installed at outskirts of greenhouse laboratory in the University of Seoul. The purpose of this research is to minimize false alarms by analyzing environmental noise. The existing system determines the intrusion alarm by analyzing the power of amplified signal, but the alarm was seriously affected by natural strong wind and heavy rainfall. The SAU(Signal Analysis Unit) sends input signals to remote server which displays intrusion alarm and stores all the information in database. The environmental noise such as temperature, humidity and wind speed was separately gathered to analyze a correlation with input signal. The input signal was analyzed for frequency characteristic using FFT(Fast Fourier Transform) and the algorithm that differentiate between intrusion alarm and environmental noise signal is improved. The proposed algorithm is applied for the site for one month as the same as the existing algorithm and the false alarm data was gathered and analyzed. The false alarm number was decreased by 98% after new algorithm was applied to the fence. The proposed algorithm improved the reliability at the field regarding environmental noise signal.

Multi-Channel Analog Front-End for Auditory Nerve Signal Detection (청각신경신호 검출 장치용 다중채널 아나로그 프론트엔드)

  • Cheon, Ji-Min;Lim, Seung-Hyun;Lee, Dong-Myung;Chang, Eun-Soo;Han, Gun-Hee
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.47 no.1
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    • pp.60-68
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    • 2010
  • In case of sensorineural hearing loss, auditory perception can be activated by electrical stimulation of the nervous system via electrode implanted into the cochlea or auditory nerve. Since the tonotopic map of the human auditory nerve has not been definitively identified, the recording of auditory nerve signal with microelectrode is desirable for determining the tonotopic map. This paper proposes the multi-channel analog front-end for auditory nerve signal detection. A channel of the proposed analog front-end consists of an AC coupling circuit, a low-power 4th-order Gm-C LPF, and a single-slope ADC. The AC coupling circuit transfers only AC signal while it blocks DC signal level. Considering the bandwidth of the auditory signal, the Gm-C LPF is designed with OTAs adopting floating-gate technique. For the channel-parallel ADC structure, the single-slope ADC is used because it occupies the small silicon area. Experimental results shows that the AC coupling circuit and LPF have the bandwidth of 100 Hz - 6.95 kHz and the ADC has the effective resolution of 7.7 bits. The power consumption per a channel is $12\;{\mu}W$, the power supply is 3.0 V, and the core area is $2.6\;mm\;{\times}\;3.7\;mm$. The proposed analog front-end was fabricated in a 1-poly 4-metal $0.35-{\mu}m$ CMOS process.

A Study on The Complex Event Detection Methods Based on Bitmap Index for Stream data Processing (스트림 데이터 처리를 위한 비트맵 인덱스 기반 복합 이벤트 검출 기법에 관한 연구)

  • Park, Yong-Min;Oh, Young-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.48 no.4
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    • pp.61-68
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    • 2011
  • Event-based service technology integrate service to detect events that occur in real time by analyzing the response. Is the core technology for real-time business and ubiquitous service environment construction. Is required event-based service technology on business processes in real-time business environment that providing rapid response to changing and custom service using a variety of information real-time monitoring and analysis in ubiquitous service environment. Last event-driven business processes can be used as a CEP(Complex Event Processing). The core of CEP technology, the event from multiple event sources analysis of events affecting and the way to handle action, is detect complex event to user. In previous studies, an event occurs that continue to perform without the need for partial operations. so many operations and spend a lot of memory is a problem. To solve these problems, event detection technique is proposed that large streams of data without processing any events, registered to configure a complex event occurs when all events in the application layer, complex event processing. The proposed method, first using a bitmap index to manage the event occurs. The complex events of the last event in response to define a trigger event. The occurrence of an event to display a bitmap index, a composite event occurrence of all event to configure the test through the point at which a trigger event occurs. Is proposed, If any event occurs to perform the operation. The proposed scheme perform operations when all event occurs without events having to perform each of the tests. As a result, avoid unnecessary operations and reducing the number of events to handle the increased efficiency of operations.