• Title/Summary/Keyword: close-proximity method

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Theoretical and Experimental Analysis of Extremely Low Frequency Magnetic Field in the Vicinity of the Transformer Station of Overhead Power Lines

  • Ghnimi, Said;Rajhi, Adnen;Gharsallah, Ali;Bizid, Youssef
    • Journal of Electrical Engineering and Technology
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    • v.13 no.4
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    • pp.1655-1662
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    • 2018
  • This paper studies the magnetic fields between the power lines which are finite length and other ones which are infinitely long around the first tower in the proximity of the power transformers. They will be used as a source of disturbance applied to the power line. The method applied in this study was gradual; develop the theoretical formulation of the magnetic fields of these lines which are finite length and other ones which are infinitely long, examine the effects of different couplings between the different neighboring lines and the distribution transformers on behavior of magnetic fields. The method also focused on the experimental results analyzing the magnetic fields which will be used as a source applied to the auditory implants EMC. The theoretical and experimental results were compared and discussed for three power lines (90kV, 150kV and 225kV) near the power station, and it proved the effect of these substations on the simulated and measured results of the magnetic field. The maximum intensities of magnetic fields measured at the height of 1m from the ground for the circuit of three lines close to each substation were significantly lower than the ICNIRP reference levels for occupational and non occupational exposures.

Accuracy Measurement of Image Processing-Based Artificial Intelligence Models

  • Jong-Hyun Lee;Sang-Hyun Lee
    • International journal of advanced smart convergence
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    • v.13 no.1
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    • pp.212-220
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    • 2024
  • When a typhoon or natural disaster occurs, a significant number of orchard fruits fall. This has a great impact on the income of farmers. In this paper, we introduce an AI-based method to enhance low-quality raw images. Specifically, we focus on apple images, which are being used as AI training data. In this paper, we utilize both a basic program and an artificial intelligence model to conduct a general image process that determines the number of apples in an apple tree image. Our objective is to evaluate high and low performance based on the close proximity of the result to the actual number. The artificial intelligence models utilized in this study include the Convolutional Neural Network (CNN), VGG16, and RandomForest models, as well as a model utilizing traditional image processing techniques. The study found that 49 red apple fruits out of a total of 87 were identified in the apple tree image, resulting in a 62% hit rate after the general image process. The VGG16 model identified 61, corresponding to 88%, while the RandomForest model identified 32, corresponding to 83%. The CNN model identified 54, resulting in a 95% confirmation rate. Therefore, we aim to select an artificial intelligence model with outstanding performance and use a real-time object separation method employing artificial function and image processing techniques to identify orchard fruits. This application can notably enhance the income and convenience of orchard farmers.

Correlation between Proximity Noise Measurement Method (CPX) and Roadside Measurement Method (SPB) for Road Traffic Noise (도로교통소음에 대한 근접소음 측정법(CPX)과 통과소음 측정법(SPB)의 상관관계)

  • Yoo, In-Kyoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.310-319
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    • 2020
  • Korea estimates the traffic noise by measuring the total traffic noise when the traffic passes (SPB; Statistical Pass-By). Another method (CPX; Close Proximity) directly measures the tire/road noise by installing a microphone near the tire. The CPX method is not a formal test method in Korea. There has been little research between CPX and SPB. This study proposes a method for estimating SPB, using the CPX, which is easy to measure. This study used the results of a large-scale test conducted by Korea Expressway Corporation (KEC) and a research paper on CPX in this section. The results by the KEC showed that the low noise pavement has a noise reduction of 10.4dB. In CPX research, the noise reduction was 10.7dB and was similar to 10.4dB in SPB. This study shows why the noise reduction is the same regardless of the position, the reason that the amount of noise reduction is similar, the difference of the noise according to the position of the microphone using the concept of noise summation and distance reduction. This study shows that including the CPX as a variable in the traffic noise prediction program is very important to improve noise prediction reliability.

Evaluation of a Traffic Noise Predictive Model for an Active Noise Cancellation (ANC) System (능동형 소음저감 기법을 위한 도로교통소음 예측 모형 평가 연구)

  • An, Deok Soon;Mun, Sung Ho;An, Oh Seong;Kim, Do Wan
    • International Journal of Highway Engineering
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    • v.17 no.6
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    • pp.11-18
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    • 2015
  • PURPOSES : The purpose of this thesis is to evaluate the effectiveness of an active noise cancellation (ANC) system in reducing the traffic noise level against frequencies from the predictive model developed by previous research. The predictive model is based on ISO 9613-2 standards using the Noble close proximity (NCPX) method and the pass-by method. This means that the use of these standards is a powerful tool for analyzing the traffic noise level because of the strengths of these methods. Traffic noise analysis was performed based on digital signal processing (DSP) for detecting traffic noise with the pass-by method at the test site. METHODS : There are several analysis methods, which are generally divided into three different types, available to evaluate traffic noise predictive models. The first method uses the classification standard of 12 vehicle types. The second method is based on a standard of four vehicle types. The third method is founded on 5 types of vehicles, which are different from the types used by the second method. This means that the second method not only consolidates 12 vehicle types into only four types, but also that the results of the noise analysis of the total traffic volume are reflected in a comparison analysis of the three types of methods. The constant percent bandwidth (CPB) analysis was used to identify the properties of different frequencies in the frequency analysis. A-weighting was applied to the DSP and to the transformation process from analog to digital signal. The root mean squared error (RMSE) was applied to compare and evaluate the predictive model results of the three analysis methods. RESULTS : The result derived from the third method, based on the classification standard of 5 vehicle types, shows the smallest values of RMSE and max and min error. However, it does not have the reduction properties of a predictive model. To evaluate the predictive model of an ANC system, a reduction analysis of the total sound pressure level (TSPL), dB(A), was conducted. As a result, the analysis based on the third method has the smallest value of RMSE and max error. The effect of traffic noise reduction was the greatest value of the types of analysis in this research. CONCLUSIONS : From the results of the error analysis, the application method for categorizing vehicle types related to the 12-vehicle classification based on previous research is appropriate to the ANC system. However, the performance of a predictive model on an ANC system is up to a value of traffic noise reduction. By the same token, the most appropriate method that influences the maximum reduction effect is found in the third method of traffic analysis. This method has a value of traffic noise reduction of 31.28 dB(A). In conclusion, research for detecting the friction noise between a tire and the road surface for the 12 vehicle types needs to be conducted to authentically demonstrate an ANC system in the Republic of Korea.

In Base-station with Multi-channels Using the Second Law of Cosines the Position Estimation Method (다채널을 가진 기지국에서 코사인 제2법칙을 사용한 위치 추정 방법)

  • Lee, Hyun-Sung;Bok, Young-Su;Shin, Hye-Jung;Park, Byung-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12B
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    • pp.1387-1398
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    • 2009
  • In the latest we will make a demand for the precision position estimation for the Mobile-station(MS)'s position. But, we have a lot of problems the position estimation method using the existing method. The Base-station(BS) measure a distance according to time delay waves to receive propagate from the MS and estimate the position using the existing circle equation with method to be selected BSs in close proximity the MS. It knows that happens a lot of error the estimated position and the true position. This paper propose that the method is selected round BSs to estimate for MS's position and estimated the angle using the second law of cosine. This paper demonstrate that using simulation the proposal method is a predominant method to compare with the existing method.

Displacement of Sand Layer during Deep Excavation (깊은 굴착에 따른 사질토 지반의 변형)

  • 유태성;신종호
    • Geotechnical Engineering
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    • v.1 no.2
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    • pp.81-92
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    • 1985
  • Braced excavation for a new building was carried out at a very close proximity of an existing tall building of T.hick columns are supported by indict.ideal spread footings on sand layer The excavation was planned to reach far below the footing level of the existing building. To assess the foundation performance and stability of the existing building, the behavior of 9round subjected to loss of confinement from excavation was analytically studied using finite element method. Field instrumentation was also conducted to monitor the actual ground responses during excavation. Based on these studies, various remedial measures weere taken to minimize the adverse effects to the building, and excavation was successfully completed. This paper presents the results from the analytical studies and field monitoring, and measured and measured responses at different stages of excavation.

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Estimating The Ratio of The CPA Distance to Velocity for Underwater Target using Bearing CPA (방위각 CPA를 이용한 수중표적의 CPA 거리와 속도의 비 추정)

  • Kim, JungHoon;Yoon, KyungSik;Seo, IkSu;Lee, KyunKyung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.6
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    • pp.146-151
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    • 2016
  • In this paper, we present a method for estimating the ratio of CPA distance to velocity of underwater target using target bearing information in CPA situation. This ratio can be estimated by previous research which is Envelope CPA using proximity sensor but it has low performance if the target is close to receiver sensor or bigger interference caused by multi-path effects. Therefore we propose a Bearing CPA technique using a target bearing information as a way to overcome.

Ultrasound-guided Pulsed Radiofrequency Lesioning of the Ulnar Nerve in a Patient with Cubital Tunnel Syndrome -A case report- (팔꿉굴증후군 환자에서 초음파를 이용한 척골신경의 박동성고 주파술의 경험 -증례보고-)

  • Ghil, Bo-Gyoung;Kil, Ho-Yeong
    • The Korean Journal of Pain
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    • v.21 no.3
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    • pp.224-228
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    • 2008
  • Ulnar nerve compression in the cubital tunnel is a common entrapment syndrome of the upper limb. Pulsed radiofrequency lesioning (PRFL) has been reported as a treatment method for relieving neuropathic pain. Since the placement of the electrode in close proximity to a targeted nerve is very important for the success of PRFL, ultrasound seems to be well suited for this technique. A 36-year-old woman presented with complaints of numbness and pain on the medial aspect of the elbow and the pain radiated down to the $4^{th}$ and $5^{th}$ fingers for 10 years after she suffered an elbow contusion, we then scheduled this woman for the ultrasound guided PRFL of the ulanr nerve. The initial ultrasound examination demonstrated a swollen nerve, loss of the fascicular pattern and an increased cross sectional area of the ulnar nerve. After confirmation of the most swollen site of the nerve via ultrasound, two sessions of PRFL were performed. The postprocedural 10 cm visual analog scale score decreased from 8 to 1 after the two sessions of PRFL.

Investigation of the Flow Dependence of a FET-Type Dissolved Oxygen Sensor and Its Reducing Method (FET형 용존 산소 센서의 유속에 의한 영향 조사와 감쇄 기법)

  • Jeong, H.;Kim, Y.J.;Lee, Y.C.;Sohn, B.K.
    • Journal of Sensor Science and Technology
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    • v.10 no.3
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    • pp.180-186
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    • 2001
  • Recently, FET type dissolved oxygen sensor was proposed to overcome the disadvantages of the amperometric Clark-type sensor. The inherent problem of the proposed sensor, however, is the flow dependence of the sensor performances since the proposed sensor detects the pH change in close proximity to the working electrode. In this study, we decided the direction which minimize the flow effect in FIA(flow injection analysis) system. And a hydrodynamic buffer layer which can reduce the flow dependence were proposed. The suggested buffer-layers were formed onto sensing area and working electrode with mixed polymer matrix of TEOS(tetraethylorthosilicate) and DEDMS(diethoxydimethylsilane).

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Ultrasound-guided Pulsed Radiofrequency Lesioning of the Phrenic Nerve in a Patient with Intractable Hiccup

  • Kang, Keum-Nae;Park, In-Kyung;Suh, Jeong-Hun;Leem, Jeong-Gill;Shin, Jin-Woo
    • The Korean Journal of Pain
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    • v.23 no.3
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    • pp.198-201
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    • 2010
  • Persistent and intractable hiccups (with respective durations of more than 48 hours and 1 month) can result in depression, fatigue, impaired sleep, dehydration, weight loss, malnutrition, and aspiration syndromes. The conventional treatments for hiccups are either non-pharmacological, pharmacological or a nerve block treatment. Pulsed radiofrequency lesioning (PRFL) has been proposed for the modulation of the excited nervous system pathway of pain as a safe and nondestructive treatment method. As placement of the electrode in close proximity to the targeted nerve is very important for the success of PRFL, ultrasound appears to be well suited for this technique. A 74-year-old man suffering from intractable hiccups that had developed after a coronary artery bypass graft and had continued for 7 years was referred to our pain clinic. He had not been treated with conventional methods or medications. We performed PRFL of the phrenic nerve guided by ultrasound and the hiccups disappeared.