• Title/Summary/Keyword: 소음유형

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A Study for Comparing Road Noise by Surface Types using NCPX (NCPX를 이용한 도로 표층 유형별 노면 소음 비교 연구)

  • Kang, Won Pyoung;Moon, Hak Ryong
    • International Journal of Highway Engineering
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    • v.15 no.6
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    • pp.61-68
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    • 2013
  • PURPOSES : The purpose of this study is to study the noise reducing effect of Micro Surfacing by comparing general asphalt, longitudinal tining and Slurry Seal. METHODS : This study measures vehicles' noise of each section by the NCPX method that can measure noise between the road surface and the tire at the field. Total sound pressure and sound pressure level by the 1/3 octave band frequency are calculated through the field data of each section. Total sound pressure level is compared by ANOVA test statistically. After ANOVA test, post-hoc test is conducted to know mean difference of surface type by Tukey. RESULTS : As the result of CPB analysis to confirm sound pressure levels by frequency, it was shown that sound pressure levels by frequency are totally similar except for those of frequency bands between 100Hz and 500Hz. The result of ANOVA test and post-hoc test, it was shown that sections of surface type have a difference. The result of Micro Surfacing was lower 2~5dB(A) than other surface type. CONCLUSIONS : It is found that the noise reduction performance of Micro Surfacing was better than other surface type.

Detection and Damping Recognition of Normal Frequency Using Fast Fourier Transform in the Vibration Acceleration Analysis System (진동가속도 분석시스템에서 고속푸리에변환을 이용한 기준진동수의 검출 및 감쇠인식)

  • Kim, Hwang Jun
    • Smart Media Journal
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    • v.8 no.2
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    • pp.16-20
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    • 2019
  • Fast Fourier Transform in the vibration acceleration analysis system has recently been utilized in the field of sensor measurement. In this paper, we propose a Fast Fourier Transform based method of detecting the normal frequency among the many frequency types of diffuse field. This normal frequency is expressed by the formula of frequency damping recognition which is calculated in a similar way to the octave center frequency. Based on this theory, this paper can more accurately inform noise producers of the degree of damping, which is different from the vibration type of diffuse field.

The Development of Public Campaign Message for Prevention of Hearing Loss (청력손실 예방을 위한 공익캠페인 메시지 개발을 위한 연구 : 20대 대학생을 대상으로)

  • Sun, Hye-Jin
    • The Journal of the Korea Contents Association
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    • v.19 no.9
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    • pp.329-337
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    • 2019
  • Prevention is very important in terms of the fact that the percentage of people in their 10s and 20s experience noise-prone hearing is so serious that it can lead to serious hearing later on. This study examines the effect of the hearing loss prevention public advertisement message on the hearing loss prevention intent of the acceptor according to the type of framing(positive/negative) and self-efficacy information provision (provide information/do not provide information). The perceived risk and future time orientation as individual characteristics of individual participants were set as variables that could influence the message effect. In this paper, we propose a message expression method and effective message delivery method in the aspect of message strategy and effect of execution when promoting understanding and interest in hearing loss prevention.

Frequency Spectrum Analysis of Corona Discharge Source Measured by Ultrasound Detector (초음파 감지기로 측정한 코로나 방전 소스의 주파수 스펙트럼 분석)

  • Cho, Hyun-Seob
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.1
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    • pp.78-82
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    • 2019
  • This paper addressed the spectrum of ultrasonic waves produced by arc and/or coronal discharge inside the switchboard. Portable ultrasound sensors are useful for detecting discharge phenomena, such as coronal means in electrical systems. However, a typical handheld ultrasound detector has a disadvantage of determining the type of problem by listening to the sound characteristics and predicting the results, as a result of the determination of whether a discharge is present. Therefore, a new method of analysis is required to distinguish ultrasonic characteristics. In this paper, we published an ultrasound analysis case study to visualize the sound of ultrasonic waves measured with ultrasonic sensors. From the results of the experiment, it was possible to detect coronal discharge and serial arc discharge without interference by the ultrasonic detection system.

Edge Computing based Escalator Anomaly Detection and Defect Classification using Machine Learning (머신러닝을 활용한 Edge 컴퓨팅 기반 에스컬레이터 이상 감지 및 결함 분류 시스템)

  • Lee, Se-Hoon;Kim, Ji-Tae;Lee, Tae-Hyeong;Kim, Han-Sol;Jung, Chan-Young;Park, Sang-Hyun;Kim, Pung-Il
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2020.07a
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    • pp.13-14
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    • 2020
  • 본 논문에서는 엣지 컴퓨팅 환경에서 머신러닝을 활용해 에스컬레이터 이상 감지 및 결함 분류를 하는 연구를 진행하였다. 엣지 컴퓨팅 기반 머신러닝을 사용해 에스컬레이터의 이상 감지 및 결함 분류를 위한 OneM2M환경을 구축하였으며 에스컬레이터에서 발생하는 소음에서 고장 유형에 따라 나타나는 주파수를 이용한다. Edge TPU를 활용해 엣지 컴퓨팅 시스템의 처리량을 최대화하고, 각 작업의 수행시간을 최소화함으로써 엣지 컴퓨팅 환경에서 이상 감지와 결함 분류를 수행할 수 있다.

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The Direction of School Forest Plans Considering Satisfaction of Elementary Students (초등학생들의 만족 유형을 고려한 학교숲 조성방향)

  • Jang, Cheol-Kyu;Jung, Sung-Gwan;Jang, Jung-Sun;Kim, Kyung-Tae;Oh, Jeong-Hak
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.4
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    • pp.42-51
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    • 2009
  • The purpose of this study is to analyze the actual conditions of school forests using a field survey and to establish the construction methods considering satisfactions of students using a satisfaction inquiry. The results of the this study are as follows: many trees had the highest score whereas reduction of noise had the lowest score in the satisfaction analysis of 15 items. According to the result of the factor analysis, 3 factors were determined to be most important from 15 items of satisfaction, and they were Environmental Function, Educational and Recreational Function, and Ecological Function. Next, students were classified into 4 groups using factor scores by cluster analysis. Group I had very high effectiveness in the Environmental Function and group II had low effectiveness in all factors. Also, group III had very high effectiveness in the Educational and Recreational Function, and group IV had very high effectiveness in the Ecological Function. According to the analysis results of the character of the school on students' group, the satisfaction of school forests was high when students of group II were few and other group's students were similar. As these schools use a lot of parts of the playground for green space, there was more school forest than at other schools. Also, students of these schools were experiencing the school forest through educational programs. Therefore, school forests should be constructed by increasing the green area and considering the satisfaction factors of students through various experience and education programs and by the way utilizing wide space than adding the tree in the garden.

Analysis of Consciousness and Model on Land for the Another use After Quarrying (채석장의 부지 활용에 대한 의식 및 모델 분석)

  • Park, Jae Hyeon
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.387-394
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    • 2012
  • The study was conducted to develop an effective forest resources use models for an alternate use of abandoned quarry by an attitude survey. According to the result of survey, a pessimistic view due to dust, noise pollution, and forest damage was 5% higher than an affirmative view by economic benefits from the development of quarry. The 42% of the respondents preferred the alternate use of abandoned quarry and the 25% of the respondents wanted an art and cultural space. The optimum size of alternate use was 5-10 ha (43%) with the requirement of nearby residents (32%). According to the SWOT analysis for abandoned quarry, the strength factors were an effective use of land, the content development of modern industrial inheritance + cultural and art fusion, attraction for nearby city and visitors, a harmony of beauty landscape and clean environment, and a sustainable increase of domestic and foreign visitors with the 5-day-work week. The opportunity factors were the improvement of traffic networks through KTX and local highway, the creation of the new growth engines with the establishment of artistic creation belts, the providing of unique cultural and art space through grafting of tour and education, the creation of local income through stone processed goods, and the vitalization of local development through eco-city. The weakness factors were a psychological remoteness and backwardness, and the weakness of staying tour infra. The threat factors were a poor financial support for sustainable development in nearby quarry and a modify of legal and institutional system for the alternated use of abandoned quarry. The developed restoration models for the alternate use in abandoned quarry are classified to a sculpture park, a waterfall and lake park, a rock-climbing, a sports park + forest park, a native botanical garden, a culture and art park, a complex park, a water storage site, a water storage site to extinguish forest fire, a geriatric hospital, an agricultural facility, and a school site types etc. The results suggest that the alternate use in the abandoned soil and stone quarry is needed to establish facility use models with consideration of user's preference.

A comparison of acoustic measures among the microphone types for smartphone recordings in normal adults (정상 성인에서 스마트폰 녹음을 위한 마이크 유형 간 음향학적 측정치 비교)

  • Jeong In Park;Seung Jin Lee
    • Phonetics and Speech Sciences
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    • v.16 no.2
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    • pp.49-58
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    • 2024
  • This study aimed to compare the acoustic measurements of speech samples recorded from individuals with normal voices using various devices: the Computerized Speech Lab (CSL), a unidirectional wired pin-microphone (WIRED) suitable for smartphones, the built-in omnidirectional microphone (SMART) of smartphones, and Bluetooth-connected wireless earphones, specifically the Galaxy Buds2 Pro (WIRELESS). This study included 40 normal adults (12 males and 28 females) who had not visited an otolaryngologist for respiratory diseases within the past three months. Participants performed sustained vowel /a/ phonation for four seconds and reading tasks with sentences ("Walk") and paragraphs ("Autumn") in a sound-treated booth. Recordings were simultaneously conducted using the four different devices and synchronized based on the CSL-recorded samples for analysis using the MDVP, ADSV, and VOXplot programs. Compared with CSL, the Cepstral Spectral Index of Dysphonia (CSIDV, CSIDS) and Acoustic Voice Quality Index (AVQI) values were lower in the WIRED and higher in the SMART. The opposite trend was observed for the L/H spectral ratios (SRV and SRS), and the WIRELESS demonstrated task-specific discrepancies. Furthermore, both the fundamental frequency (F0) and the cepstral peak prominence of the vowel samples (CPPV) had intraclass correlation coefficient (ICC) values above 0.9, indicating high reliability. These variables, F0 and CPPV were considered highly reliable for voice recordings across different microphone types. However, caution should be exercised when analyzing and interpreting variables such as the SR, CSID, and AVQI, which may be influenced by the type of microphone used.

A Study of the Functional Improvement for Comfortable Expressway Service Areas - Metropolitan Expressway Service Areas - (고속도로 휴게소 환경개선을 위한 기능 증진 방안 연구 - 수도권 휴게소를 중심으로 -)

  • Lee, Won-Myoung;Han, Bong-Ho;Kim, Jong-Yup;Park, Seok-Cheol
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.3
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    • pp.63-76
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    • 2015
  • This study was carried out to suggest improvement plans for problems with the landscape areas of highway service areas. The survey factors were land use, placement of green area and land coverage in terms of spatial and environmental property. Noise and topographic structure in detached green areas were surveyed in terms of impact factor. The status of the planting area around each service area was analysed in regards to planting structure and planting landscape. As a result, the mean of rations of land use were 81.6% building and 18.4% green areas, which were composed of 5.4% landscape area, 9.1% buffer area, etc. Planting areas as usable space accounted for only 0.7%, and the result of noise measurement was different according to the distribution of highway and service area and type of detached green area. The mean of ratio of planting area was 18.4%, which consists of 6.7% landscape planting, 3.4% other green area, 4.6% buffer area, 2.0% buffer and landscape area, 1.1% shade planting and 0.5% landscape and shade planting. Most planting areas aim at landscape appreciation and areas in which visitors can relax and gain recreation were insufficient. The planting structures of service areas were 52.2% canopy layer, 11.8% shrubs and 9.4% canopy and shrub layers, and most of the planting areas were a single layer of green area. Multi-layered planting structures in the landscape and buffer areas were required and a shade planting area was needed to improve amenities as planting canopy layered trees. This study suggested improvement methods for based environments, spatial function and planting function in landscape areas.

Analysis of Inter-Questionnaire Agreement in Determining Sasang Constitution (설문지(設問紙)에 의한 사상체질(四象體質) 판정(判定)의 일치도(一致度) 분석(分析))

  • Park, Seong-sik;Park, Eun-kyung;Choi, Jae-young
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.1
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    • pp.103-117
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    • 1999
  • 1. Background and Purpose : Sasang Constitutional medicine is baon dividing individuals' constitutions into four categories. Determination of an individual's constitution, however, can be different according to who he or she consults with since it depends solely on the examiner's own perception and methods. Currently, the use of self-reporting questionnaires is accepted as a general approach in clinical settings, but the results of different questionnaires tend to be inconsistent. In this study, we investigated how different the results of the questionnaires are and what the inter-questionnaires agreement is. 2. Method : 1595 peoples who volunteered our research from 1997 to 1999 and were evaluated disease free were asked to mark out three questionnaires: Sasang Pattern Identification Questionnaire, QSCC I and QSCCII(QSCC I was completed by 348 patients only). 3. Results and Conclusions : Three questionnaires above produced different results as excepted. In Sasang Pattern Identification Questionnaire, the Soeumin accounted for 55.9%. With the modified version of Sasang Pattern Identification Questionnaire, the Taeumin was the majoriy(39.1 %) and, QSCCII also showed similar results(34.8% of Taeumin). In contrast, the QSCC I revealed the majority consisted of the Soyangin (59.1 %). In terms of analysis on inter-questionnaire agreement, Sasang Pattern Identification Questionnaire and its modified version showed the highest agreement of 66.3, followed by 55.6% of QSCCII and the modified version from Sasang Pattern Identification Questionnaire. Therefore, we concluded that the ideal choice to determine an individual's constitution, as far as questionnaires go, is to take results from both the modified version from Sasang Pattern Identification Questionnaire and QSCCII. We found the use of QSCC I can be confusing to reach a satisfactory agreement.

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