• Title/Summary/Keyword: Self Noise

Search Result 575, Processing Time 0.058 seconds

Implementation of Analog Signal Processing ASIC for Vibratory Angular Velocity Detection Sensor (진동형 각속도 검출 센서를 위한 애널로그 신호처리 ASIC의 구현)

  • 김청월;이병렬;이상우;최준혁
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.40 no.4
    • /
    • pp.65-73
    • /
    • 2003
  • This paper presents the implementation of an analog signal-processing ASIS to detect an angular velocity signal from a vibrator angular velocity detection sensor. The output of the sensor to be charge appeared as the variation of the capacitance value in the structure of the sensor was detected using charge amplifiers and a self oscillation circuit for driving the sensor was implemented with a sinusoidal self oscillation circuit using the resonance characteristics of the sensor. Specially an automatic gain control circuit was utilized to prevent the deterioration of self-oscillation characteristics due to the external elements such as the characteristic variation of the sensor process and the temperature variation. The angular velocity signal, amplitude-mod)Hated in the operation characteristics of the sensor, was demodulated using a synchronous detection circuit. A switching multiplication circuit was used in the synchronous detection circuit to prevent the magnitude variation of detected signal caused by the amplitude variation of the carrier signal. The ASIC was designed and implemented using 0.5${\mu}{\textrm}{m}$ CMOS process. The chip size was 1.2mm x 1mm. In the experiment under the supply voltage of 3V, the ASIC consumed the supply current of 3.6mA and noise spectrum density from dc to 50Hz was in the range of -95 dBrms/√Hz and -100 dBrms/√Hz when the ASIC, coupled with the sensor, was in normal operation.

Self-Adaptive Performance Improvement of Novel SDD Equalization Using Sigmoid Estimate and Threshold Decision-Weighted Error (시그모이드 추정과 임계 판정 가중 오차를 사용한 새로운 SDD 등화의 자기적응 성능 개선)

  • Oh, Kil Nam
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.17 no.8
    • /
    • pp.17-22
    • /
    • 2016
  • For the self-adaptive equalization of higher-order QAM systems, this paper proposes a new soft decision-directed (SDD) algorithm that opens the eye patterns quickly as well as significantly reducing the error level in the steady-state when it is applied to the initial equalization stage with completely closed eye patterns. The proposed method for M-QAM application minimized the computational complexity of the existing SDD by the symbol estimated based on the two symbols closest to the observation, and greatly simplified the soft decision independently of the QAM order. Furthermore, in the symbol estimating it increased the reliability of the estimates by applying the superior properties of the sigmoid function and avoiding the erroneous estimation of the threshold function. In addition, the initialization performance was improved when an error is generated to update the equalizer, weighting the symbol decision by the threshold function to the error, resulting in an extension of the range of error fluctuations. As a result, the proposed method improves remarkably the computational complexity and the properties of initialization and convergence of the traditional SDD. Through simulations for 64-QAM and 256-QAM under multipath channel conditions with additive noise, the usefulness of the proposed methods was confirmed by comparing the performance of the proposed 2-SDD and two forms of weighted 2-SDD with CMA.

Gaussian Noise Reduction Algorithm using Self-similarity (자기 유사성을 이용한 가우시안 노이즈 제거 알고리즘)

  • Jeon, Yougn-Eun;Eom, Min-Young;Choe, Yoon-Sik
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.44 no.5
    • /
    • pp.1-10
    • /
    • 2007
  • Most of natural images have a special property, what is called self-similarity, which is the basis of fractal image coding. Even though an image has local stationarity in several homogeneous regions, it is generally non-stationarysignal, especially in edge region. This is the main reason that poor results are induced in linear techniques. In order to overcome the difficulty we propose a non-linear technique using self-similarity in the image. In our work, an image is classified into stationary and non-stationary region with respect to sample variance. In case of stationary region, do-noising is performed as simply averaging of its neighborhoods. However, if the region is non-stationary region, stationalization is conducted as make a set of center pixels by similarity matching with respect to bMSE(block Mean Square Error). And then do-nosing is performed by Gaussian weighted averaging of center pixels of similar blocks, because the set of center pixels of similar blocks can be regarded as nearly stationary. The true image value is estimated by weighted average of the elements of the set. The experimental results show that our method has better performance and smaller variance than other methods as estimator.

An Investigation on the self-consciousness Symptoms of the Clerical Workers attendant upon Office Automation (사무 자동화에 따른 사무직 근로자의 건강과 연관된 자각 증상에 대한 조사연구)

  • Jung, Mi Wha
    • Korean Journal of Occupational Health Nursing
    • /
    • v.3
    • /
    • pp.54-70
    • /
    • 1993
  • According as the automation of clerical work(OA ; Office Automation) develops, the use of VDT(Visual or Video Display Terminal) is increasing suddenly. But, in proportion to the spread of office automation(OA tendency), the self-conciousness syptom attendant upon the work is appearing also (Kim, Jung Tae, Lee, Young Ook, 1990). The apparatuses of office enable the clerical workers to be convenient and perform mass businesses. But, they are increasing the opportunity to be exposed to VDT syndrom, techno stress, computer terminal disease, pain by muscle strain(RSI), bradycausia of noise nature, and electromagnetic waves, etc. which are referred to as the new type of occupational diseases to the workers. It is the real situation that the workers to use VDT is complaining of the physical inconvenience sense in the recent newspaper and literature, it is the point of time that the sydrome to come from VDT use and computer terminal disease, etc. must be classified into the occupational disease(Lee, Kwang Young 1990, Lee, Kyoo Hak 1990, Lee, Won Ho 1991, Lee, Si Young 1991, Lee, Joon 1991, Choi, Young Tae 1991, Heo, Seung Ho 1989). In addition, it is the real situation that the scientifitic study result about the scope that electromagnetic waves has influence on the human body has not been suggested yet, and criticism on the stable exposure permission standard about electromagnetic waves to be emitted from VDT and on the problem in the health about electromagnetic waves is continuing. (IEEE Spectrum, 1990). In addition according to the experience of nursery business of industry field, it is the real situation that the patients who consult complaining of physical and mental inconvenience sence, among the users of apparatus of office automation, are reaching 10% of the patients coming to doctor's room. Therefore, it is necessary to confirm the self-consciousness symptom that the clerical workers complain of multilaterally with the actual state examination about the use of the apparatuses of offices automaton. Thus, this study was tried as th basic data for the cosultation and education for the maintenance and furtherance of the health of workers as the nurse of industry field, by confirming the contents of self-consciousness symptom attendant upon the use of the apparatus for office outomation making the financial institution in which the spparatus for office automation in most frequently used as the subject, and by examining whether there is the difference according to the subject of study, the data were collected, by using the questionnaire method, making 200 workers who consented to the study participation as the subject, among the persons who have spent over 3 months since they used the apparatuses for office automation and didn't receive the treatment in hospital due to the clerical disease for recent 3 years. The period of data collection was from Oct. 9, 1991 to Oct. 12. As for the measurement instrument about the complaint if self-consciousness symptom attendant upon the use of apparatuses fo office automation, the question item on the complaint symptom of health problem attendant upon the treatment of VDT that Kim(1991) developed and on CMI health problem and the question items on the fatigue degree due to industry were used by previous examination to 25 persons. Collected data were analyzed with the statistical method such as percentage, arithmetic mean, Person correlation coeffient, Kai square verfication, t-test, ANOVA, etc. by using SPSS/PC+ program, and the result is as follows : 1. The self-consciousness symptom that the clerical workers complained of most frequetly appeared high in 'My eyes are tired'(99.4%), 'I feel fatigue and weariness'(99.4%), 'I feel that my head is heavy5(90.0%), 'eyesight fell'(88.8%), 'I have a stiff neck'(88.8%), 'I fell pain in the shoulder'(85.0%), 'I feel cold and painful in the eyes'(76.9%), 'I feel the dry sense of eyeball'(76.2%), 'My nerves are edgy, and I an fretful, (75.6%), 'I feel pain in the waist'(73.2%) and 'I fell pain in the back'(72.8%). It emerged that the subject use the apparatuses for office automation complained of self-consciousness symptoms related to visual symptoms and musculoskeletal symptoms. 2. As for the general feature of examination subjects, the result to see the distribution by classifying into sex, age, school career, use career of apparatuses for office automation, skillfulness degree of the use of apparatus for office automation, use hours of the apparatuses for office automation per 1 day, type of business of the apparatus for office automation, rest hours during the use of apparatus for office automation, satifaction degree of business of office automation, and work circumstance, etc. emerged as follows : As for the sex of subjects, the distribution showed that men were 58.8% and women were 41.3%, Age was average 26.9. As the distribution of school career, the distribution showed that4below the graduation of high school' was 58.8%, 'graduation from junior college-university' was 35.0%, and 'over graduate school' was 6.3%. In the question to ask the existence or non-existence of experience of health consultation in connection with the work of office automation, the response that I had the consultation exprience and I feel the necessity emergerd as 90.1% And, the case that the subject who didn't wear the glasses or lens before using the OA apparatus wear glasses or lens after using OA apparatus emerged as 28.3% of whole. As for the existence or non-existence of use career of OA apparatus, the case under 3 years was highest as 52. 7%. As for the skillfulnness degree about the use of apparatus for office automation, most of them are skillful with the fact that 'common' was 44.4%, 'skill' was 42.5%, and 'unskillful' was 13.1% As for the use average hours of the apparatus for office automation per 1 day, the distribution showed that the case under 3-6 hours was 33.1%, the case under 6-9 hours was 28.1%, the case under 3 hours was 30.6%, and the case over 9 hours was 8.1% Main OA business and the use hours for 1 day showed in the order of keeping and retrieval, business of information transmission(162min), business of information transmission(79.3 min), business of document framing(55.5 min), and business of duplication and printing(25.4min). as for the rest during the use of apparatus for affice automation, that I take rest occasion demands the major portion, but that I take after completing the work emerged as 33.8%. Though the subiness gets to be convenient by the use of the apparatus for of office automation, respondents who showed the dissatisfaction about the present OA business emergd high as 78.1%. The work circumstances of each office was good with the fact that the temperature of office was 21.8, noise was average 42.7db, and the illumination was average 364.4 lx, in the light of ANSi/HFS 100 Standard. 3. Sight syptom, musculoskeletal symptom, skin and other symptoms showed the significant difference according to the extent of skillfulness of the apparatus for office automation. All the symptoms exept skin symptom showed the difference according to the use hours of the apparatus for office automation. All the question items exept the sytoms of digestive organs and the rest hours during the apparatus for office automation showed the signicant difference. The question item which showed the signicant difference from the satisfaction degree of present OA business showed the significant difference from all the question item classified into 6 groups. But, age and school career didn't significant difference from the complaint of any self-consciousness symptoms.

    . In conclusion, the self-consciousness symptoms of the subjects to use OA apparatus appeared differently, according to sex distiction, skillfull degree of OA apparatus, use hours of OA apparatus, the rest hours during th use of OA apparatus, and the satiafaction degree of persent business. Therefore, it is necessary that the nurse in the inuctry field must recognize to receive the education about the human technological physical condition which is most proper for te use of OA apparatus and about the proper rest method until they get accustomed to the use of OA apparatus. In addition, the simple exercise relax the tention of muscle due to the repetitive simple movement, and the education for the protection of eyesight are necessary.

  • PDF
  • Permission of the Claim that Prohibits Military Aircraft Operation Nearby Residential Area - Supreme Court of Japan, Judgement Heisei 27th (Gyo hi) 512, 513, decided on Dec. 8, 2016 - (군사기지 인근주민의 군용기 비행금지 청구의 허용 여부 - 최고재(最高裁) 2016. 12. 8. 선고 평성(平成) 27년(행(行ヒ)) 제512, 513호 판결 -)

    • Kwon, Chang-Young
      • The Korean Journal of Air & Space Law and Policy
      • /
      • v.33 no.1
      • /
      • pp.45-79
      • /
      • 2018
    • An increase of airplanes and military aircraft operation lead to significant demanding of residential claims by people who live in nearby airports and military bases due to noise, vibration and residential damages caused by aircraft operations. In recent years, a plaintiff has filed a lawsuit against the defendant, claiming the prohibition of using claimant's possessed land as a helicopter landing route, and the Daejeon High Court was in favour of the plaintiff. Although the Supreme Court later dismissed the Appeal Court decision, it is necessary to discuss the case of setting flight prohibited zone. In Japan, the airport noise lawsuits have been filed for a long time, mainly by environmental groups. Unlike the case that admitted residential damages caused by noise, the Yokohama District Court for the first time sentenced a judgment of the prohibition of the flight. This ruling was partially changed in the appellate court and some of the plaintiffs' claims were adopted. However, the Supreme Court of Japan finally rejected such decision from appeal and district courts. Atsugi Base is an army camp jointly used by the United States and Japan, and residents, live nearby, claim that they are suffering from mental damage such as physical abnormal, insomnia, and life disturbance because of the noise from airplane taking off and landing in the base. An administrative lawsuit was therefore preceded in the Yokohama District Court. The plaintiff requested the Japan Self-Defense Forces(hereinafter 'JSDF') and US military aircraft to be prohibited operating. The court firstly held the limitation of the flight operation from 10pm to 6am, except unavoidable circumstance. The case was appealed. The Supreme Court of Japan dismissed the original judgment on the flight claim of the JSDF aircraft, canceled the first judgment, and rejected the claims of the plaintiffs. The Supreme Court ruled that the exercise of the authority of the Minister of Defense is reasonable since the JSDF aircraft is operating public flight high zone. The court agreed that noise pollution is such an issue for the residents but there are countermeasures which can be taken by concerned parties. In Korea, the residents can sue against the United States or the Republic of Korea or the Ministry of National Defense for the prohibition of the aircraft operation. However, if they claim against US government regarding to the US military flight operation, the Korean court must issue a dismissal order as its jurisdiction exemption. According to the current case law, the Korean courts do not allow a claimant to appeal for the performance of obligation or an anonymous appeal against the Minister of National Defense for prohibiting flight of military aircraft. However, if the Administrative Appeals Act is amended and obligatory performance litigation is introduced, the claim to the Minister of National Defense can be permitted. In order to judge administrative case of the military aircraft operation, trade-off between interests of the residents and difficulties of the third parties should be measured in the court, if the Act is changed and such claims are granted. In this connection, the Minister of National Defense ought to prove and illuminate the profit from the military aircraft operation and it should be significantly greater than the benefits which neighboring residents will get from the prohibiting flight of military aircraft.

    Application of HHIE-S(Hearing Handicap Inventory for the Elderly-Screening version) to screening test of noise-induced hearing loss (소음성 난청 선별검사에 HHIE-S(Hearing Handicap Inventory for the Elderly-Screening version)의 적용)

    • Lee, Mi-Young;Suh, Suk-Kwon;Lee, Choong-Won
      • Journal of Preventive Medicine and Public Health
      • /
      • v.29 no.3 s.54
      • /
      • pp.539-553
      • /
      • 1996
    • The study was conducted from May to September in 1994 to investigate applicability of the Hearing Handicap Inventory for the Elderly-Screening version(HHIE-S) in parallel with the pure-tone audiometer to the initial screening test of noise-induced hearing loss(NIHL) in some noise-exposed workers. Subjects were selected by systemic sampling that took every 10th person from 6, 700 workers taking the annual occupational health examination by the department of Health Maintenance of Dongsan Hospital Keimyung University in Taegu. The authors administered the pure-tone audiometric test and self-reported questionnaire of HHIE-S including items of sociodemographic and job-related variables concurrently. The final subjects analysed were 1,019(488 males and 531 females) excluding fourteen persons who had many missing values in their questionnaires. The reliability coefficients of HHIE-S scale by Cronbach's alpha were 0.84. In the univariate analysis of hearing handicap measured by the HHIE-S, work duration, military service and the hearing threshold loss at 1KHz and 4KHz by the initial audiometer were significant in males while age, work duration and hearing threshold loss at 1KHz and 4KHz were significant in females. In the stepwise linear regression analysis, hearing threshold loss at 1KHz and 4KHz, was the only selected variable explaining the hearing handicap in males and hearing threshold loss at 1KHz and 4KHz, age, and work duration were selected in females. In ROC curves for HHIE-S scores against NIHL as gold standard which was defined by the follow-up audiogram as more than 30dB of the average of 0.5/1/2KHz and 50dB at 4KHz, the optimal cutoff for the parallel HHIE-S appeared to be 8. The results suggest that HHIE-S appeared to have some reliability and validity in this data and might be used in screening NIHL in parallel with pure-tone audiometer in noise-exposed workers.

    • PDF

    Development of V-band Wireless Transceiver using MMIC Modules (MMIC 모듈을 이용한 V-band 무선 송수신 시스템의 구축)

    • Lee, Sang-Jin;An, Dan;Lee, Mun-Kyo;Go, Du-Hyun;Jin, Jin-Man;Kim, Sung-Chan;Kim, Sam-Dong;Park, Hyun-Chang;Park, Hyung-Moo;Rhee, Jin-Koo
      • Proceedings of the IEEK Conference
      • /
      • 2005.11a
      • /
      • pp.575-578
      • /
      • 2005
    • We report on a low-cost V-band wireless transceiver with no use of any local oscillator in the receiver block using a self-heterodyne architecture. V-band Microwave monolithic IC (MMIC) modules were developed to demonstrate the wireless transceiver using coplanar waveguide (CPW) and GaAs PHEMT technologies. The MMIC modules such as the MMIC low noise amplifier (LNA), medium power amplifier (MPA) and the up/down-mixer were installed in the transceiver system. To interface the MMIC chips with the component modules for the transceiver system, CPW-to-waveguide fin-line transition modules of WR-15 type were designed and fabricated. The fabricated LNA modules showed a $S_{21}$ gain of 8.4 dB and a noise figure of 5.6 dB at 58 GHz. The MPA modules exhibited a gain of 6.9 dB and a $P_1$ $_{dB}$ of 5.4 dBm at 58 GHz. The conversion losses of the up-mixer and the down-mixer module were 14.3 dB at a LO power of 15 dBm, and 19.7 dB at a LO power of 0 dBm, respectively. From the measurement of V-band wireless transceiver, a conversion gain of 0.2 dB and a P $_{1dB}$ of 5.2 dBm were obtained in the transmitter block. The receiver block showed a conversion gain of 2.1 dB and a P $_{1dB}$ of -18.6 dBm. The wireless transceiver system demonstrated a successful data transfer within a distance of 5 meters.

    • PDF

    Effects of Field Configuration Shielding Area and Changing of Density and Sensitivity on Tube Current and Image Quality in Automatic Exposure Control System (자동노출제어장치의 채광창 차폐정도와 농도, 감도의 변화가 관전류량과 영상품질에 미치는 영향)

    • Jeong, Min-Gyu;Seoung, Youl-Hun
      • Journal of the Korean Society of Radiology
      • /
      • v.14 no.5
      • /
      • pp.635-642
      • /
      • 2020
    • The purpose of this study was to analysis the effects of shielding area of field configuration with changing of sensitivity and density on tube current (milliampere-seconds, mAs) and image quality in automatic exposure control (AEC) system. The equipment used a digital radiography device (Digital Diagnost, Philips, Netherlands), which has a integral type with an X-ray tube and an indirect digital detector. The AEC system conditions were consisted of 9 setting environments, that mode changing of the sensitivity (S200, S400, S800) and the density (+2.5, 0, -2.5). The tube current evaluated automatically exposed mAs under 81 combination conditions crossed by AEC conditions in fixed at 40 kVp. The image quality evaluated the radiographic images that selected valid images by visual assessment the radiographic images of the self-produced conical pyramid phantom and then measured their signal to noise ratio (SNR). As a result, the maximum tube current was 60.0 mAs that automatically exposed conditions were the 100% of shielding area and the sensitivity of S200 and the density of +2.5. The minimum tube current was 0.9 mAs with non-shielding area and the sensitivity of S800 and the density of -2.5. When the shielded area 0% with the sensitivity of S200 and the density of +2.5, the maximum SNR was the highest as 25.2. But when the shielded area 25% with the sensitivity of S800 and the density of -2.5, the minimum SNR was the lowest as 4.7.

    Consumer's Behaviors on the Laundering of Baby's Clothing - Comparison of Washing Machine Types - (영.유아복 세탁에 관한 소비자 행동 연구 - 세탁기 유형별 비교 -)

    • Lee, Su-Yeon;Le, Jeong-Sook
      • Journal of the Korean Society of Clothing and Textiles
      • /
      • v.31 no.8
      • /
      • pp.1231-1239
      • /
      • 2007
    • The purpose of this study was to investigate consumer's behaviors on the laundering of baby's clothing according to washing machine types. The subjects were 255 consumers with babies(0-2 years) in Korea. The data were collected with a self-administered questionnaire and analyzed by Chi-square test and multiple response analysis, and SPSS 12.0 statistics package was used. Consumers were separated into two groups according to washing machine types with general pulsator type and drum-type. Consumer's behaviors between general pulsator type group and drum-type group of washing machines were also examined. The results of this study were as follows. In the consumer satisfaction for washing machine, mostly drum-type group of consumers were satisfied with their washing machines. As the reasons of washing machine's dissatisfaction, noise, washing time and low washing efficiency were high in the pulsator type group, and washing time, noise and high price in the drum-type washing machine group. The consumers concerned about separation of clothing and laundering label while they washed laundry by washing machine. However, they didn't separate clothing because the small volume of laundry and a long washing time. The most interest and required thing of consumers was complete rinsing without any detergents used in washing as well as the removal of soils for baby's clothing regardless of two washing machine types. And they complained food soils like milk and mother's milk etc. were not completely removed by washing machine. As a whole the washing frequency of baby's laundry was once per a day and the rinsing also more than three times per a laundry. Most of the consumers used a private detergents for baby's clothing(detergents for baby's clothing only), and preferred to the high or boiled temperature washing as a desirable baby's laundering. There were significant differences between general pulsator type group and drum-type group of washing machines on the laundering of baby's clothing in this study.

    Dilated convolution and gated linear unit based sound event detection and tagging algorithm using weak label (약한 레이블을 이용한 확장 합성곱 신경망과 게이트 선형 유닛 기반 음향 이벤트 검출 및 태깅 알고리즘)

    • Park, Chungho;Kim, Donghyun;Ko, Hanseok
      • The Journal of the Acoustical Society of Korea
      • /
      • v.39 no.5
      • /
      • pp.414-423
      • /
      • 2020
    • In this paper, we propose a Dilated Convolution Gate Linear Unit (DCGLU) to mitigate the lack of sparsity and small receptive field problems caused by the segmentation map extraction process in sound event detection with weak labels. In the advent of deep learning framework, segmentation map extraction approaches have shown improved performance in noisy environments. However, these methods are forced to maintain the size of the feature map to extract the segmentation map as the model would be constructed without a pooling operation. As a result, the performance of these methods is deteriorated with a lack of sparsity and a small receptive field. To mitigate these problems, we utilize GLU to control the flow of information and Dilated Convolutional Neural Networks (DCNNs) to increase the receptive field without additional learning parameters. For the performance evaluation, we employ a URBAN-SED and self-organized bird sound dataset. The relevant experiments show that our proposed DCGLU model outperforms over other baselines. In particular, our method is shown to exhibit robustness against nature sound noises with three Signal to Noise Ratio (SNR) levels (20 dB, 10 dB and 0 dB).