• 제목/요약/키워드: abnormal behavior

검색결과 552건 처리시간 0.031초

프로세스 압축기 틸팅패드 저널베어링의 비정상 고온거동 트러블슈팅 (Abnormal High-Temperature Behavior Troubleshooting of Process Compressor Tilting Pad Journal Bearing)

  • 이안성;이운실;최동훈
    • Tribology and Lubricants
    • /
    • 제33권2호
    • /
    • pp.37-44
    • /
    • 2017
  • A DE-side LBP tilting pad journal bearing of a 1-stage overhung heat-pump compressor in a propylene process exhibited abnormal high-temperature behavior. Its temperature had been relatively high at $78^{\circ}C$ from the beginning of operation. In 2014, after three years of operation, it increased suddenly and reached $103^{\circ}C$. Installing a varnish removal equipment and others managed to stabilize the temperature at $95^{\circ}C$. We undertook a troubleshooting approach for reviewing the comprehensive status and integrity of the temperature design of the bearing. We performed lubrication and heat-balance analysis, based on the design engineering data and documents supplied by the OEM. For the base design data of DE-side TPJB, evaluating the effects of key design variables on bearing metal temperature showed that firstly, increasing the bearing clearance and supply oil flow-rate, and next, changing the oil type, and finally, increasing the machined pad clearance and offset, are more effective in reducing the bearing metal temperature. Furthermore, a clarification meeting with the OEM revealed that an incorrect decision had been made to decrease the bearing clearance to eliminate the SSV harshness issue, while not maintaining a sufficient oil flow-rate. We conducted a detailed retrofit design analysis, wherein we increased the oil flow-rate and bearing clearance by decreasing the preload. We predicted that the bearing temperature would decrease to $63^{\circ}C$ from $75.7^{\circ}C$ even at the rerate condition. Finally, after installing and operating a retrofit replacement bearing in 2015, the bearing temperature stabilized at a low temperature of $65^{\circ}C$. Currently (January. 2017), two year later, the bearing metal temperature remains at $65^{\circ}C$. Therefore, we can conclude that the abnormal high-temperature behavior of the bearing has been resolved completely.

AE에 의한 치과용 다이아몬드 버의 연삭가공 특성 (Grinding Characteristics of Diamond Burs in Dentistry)

  • 이근상;임영호;권동호;소의열
    • 한국생산제조학회지
    • /
    • 제8권3호
    • /
    • pp.76-82
    • /
    • 1999
  • This study was carried out to verify finding performance of dental diamond bur and investigate the possibility of AE application in density field. Work pieces were made of acryl and bovine respectively for the experiments in this study. Grinding test was conducted to get the data of grinding resistance and specific finding energy of low different types of diamond bur by using tool dynamometer. AE signal was acquired to verify grinding process in the AE measuring system. AErms value was increased as the grinding velocity and depth were increasing, but it decreased as the feed rate was increasing. The case of the small value of AE signal is due to abnormal grinding in D type diamond bur. By analyzing AErms start and finish time of grinding working, abnormal grinding state can be confined. Abnormal state can be found through the behavior of AE signal in the finding working. As a result, it is expected that forecast of abnormal state is possible using AE equipments under real time process.

  • PDF

패스트 데이터 기반 실시간 비정상 행위 탐지 시스템 (Real-time Abnormal Behavior Detection System based on Fast Data)

  • 이명철;문대성;김익균
    • 정보보호학회논문지
    • /
    • 제25권5호
    • /
    • pp.1027-1041
    • /
    • 2015
  • 최근, Verizon(2010), 농협(2011), SK컴즈(2011), 그리고 3.20 사이버 테러(2013)와 같이 소중한 정보가 누출되고 자산에 피해가 발생한 후에야 보안 공격을 인지하는 APT (Advanced Persistent Threat) 공격 사례가 증가하고 있다. 이러한 APT 공격을 해결하고자 이상 행위 탐지 기술 관련 연구가 일부 진행되고 있으나, 대부분 알려진 악성 코드의 시그너쳐 기반으로 명백한 이상 행위를 탐지하는데 초점을 맞추고 있어서, 장기간 잠복하며 제로데이 취약점을 이용하고, 새로운 또는 변형된 악성 코드를 일관되게 사용하는 APT 공격에는 취약하여, 미탐율이 굉장히 높은 문제들을 겪고 있다. APT 공격을 탐지하기 위해서는 다양한 소스로부터 장기간에 걸쳐 대규모 데이터를 수집, 처리 및 분석하는 기술과, 데이터를 수집 즉시 실시간 분석하는 기술, 그리고 개별 공격들 간의 상관(correlation) 분석 기술이 동시에 요구되나, 기존 보안 시스템들은 이러한 복잡한 분석 능력이나 컴퓨팅 파워, 신속성 등이 부족하다. 본 논문에서는 기존 시스템들의 실시간 처리 및 분석 한계를 극복하기 위해, 패스트 데이터 기반 실시간 비정상 행위 탐지 시스템을 제안한다.

건강검진 결과에 의한 사후관리 필요여부와 건강행위와의 관련성 - 국민건강영양조사, 제4기 1차년도 자료를 중심으로 - (Relationship between Health Behavior and Need for Follow-up According to Health Examination Results - National Health and Nutritional Examination Survey(KNHANES VI-1) -)

  • 최지헌;황인영
    • 한국농촌간호학회지
    • /
    • 제6권1호
    • /
    • pp.23-32
    • /
    • 2011
  • Purpose: This study was conducted to estimate the relationship between health behavior and follow-up needed for results of health examinations. Methods: The participants were 2,245 adults over age 19. Data from the National Health and Nutritional Examination Survey VI-1 was used. Health behavior was defined as smoking, alcohol consumption, physical activity, hours of sleep and BMI. Those who needed follow-up care after a health examination were defined as having abnormal blood pressure, abnormal blood sugar, or abnormal blood cholesterol. Results: The proportion needing follow-up was 77.4%. The odds ratio (95%CI) for needing follow-up for blood pressure for men was 1.59 (1.18-2.15) with excessive alcohol consumption over one month, and 2.33 (1.73-3.13) with obesity, and for women, 3.55 (2.66-4.74) with obesity. For blood sugar in men it was 1.59 (1.18-2.15) with excessive alcohol consumption and 2.33 (1.73-3.13) with obesity, and for women, 3.55 (2.66-4.74) with obesity. For low HDL-C in men it was 0.53 (00.40-0.72) with excessive alcohol consumption and 2.39 (1.81-3.15) with obesity, and in women, 0.73 (0.57-0.94) with excessive alcohol consumption and 1.66 (1.29-2.14) with obesity. For high triglycerides it was 2.37 (1.42-2.39) with smoking and 2.34 (1.70-3.22) with obesity in men and in women, 1.51 (1.05-2.16) with obesity. Conclusions: The results of this study indicate that obesity is associated with high blood pressure, high blood sugar, low HDL-C, and high triglycerides.

Introduction of tmie Gene Can Recover the Hearing Impairment and Abnormal Behavior in the Circling Mouse

  • Shin, Mi-Jung;Park, Seo-Jin;Pare, Hum Dai;Ryoo, Zae-Young
    • Reproductive and Developmental Biology
    • /
    • 제34권2호
    • /
    • pp.63-71
    • /
    • 2010
  • The spontaneous mutant circling mouse (cir/cir) shows a circling behavior and hearing loss. We produced transgenic mice overexpressing transmembrane inner ear (tmie) gene, the causative gene, for the phenotypic rescue of the circling mouse. Through the continuous breeding with circling mice, the cir/cir homozygous mice carrying the transgene (cir/cir-tg) were produced. The rescued cir/cir-tg mice were able to swim in the water with proper orientation and did not show any circling behavior like wild type mice. Western blot and immunohistochemical analysis exhibited that the transgenic tmie was expressed in the inner ear. Inner and outer hair cells were recovered in the cochlea and spiral ganglion neurons were also recovered in the rescued mice. Auditory brainstem response (ABR) test demonstrated that the cir/cir-tg mice are able to respond to sound. This study demonstrates that tmie transgene can recover the hearing impairment and abnormal behavior in the circling mouse.

잠재계층분석을 활용한 결혼이주여성의 건강관련행동 군집유형과 영향요인 (Health related behavior patterns and associated factors among marriage immigrant women using latent class analysis)

  • 조원섭;유승현;김혜경
    • 보건교육건강증진학회지
    • /
    • 제32권5호
    • /
    • pp.17-31
    • /
    • 2015
  • Objectives: This paper aims to identify the health related behaviors patterns and its associated factors among marriage immigrant women in Korea, and discusses their application to health promotion strategies. Methods: The study participants were 7,591 immigrant wives in Gyeonggi province who participated in health examinations conducted by the Korea Association of Health Promotion in 2011-2013. The participants completed self-administered questionnaires on sociodemographics, psychological characteristics, health status and health care factors, and health related behaviors. Results: A 3-latent-class model of health behaviors was identified related to 'lack of physical activity', 'abnormal diet', and 'not experienced medical check-up': 'high risk class', 'middle risk class', and 'low risk class'. Most of the participants belong to 'middle risk class'. Country of origin, age, length of stay, number of children, work status, health insurance status, and unmet health care needs were associated with problematic health behaviors in middle risk health behavior class. Conclusions: Health promotion and intervention programs for marriage immigrant women and their family members need to consider the health behavior patterns of physical inactivity, abnormal diet and no medical check-up and develop multiple behavior intervention with pre-existing program modification.

비정상 상태 운전 시 정면충돌에서의 상해 분석 (Analysis of Driver Injuries Caused by Frontal Impact during Abnormal Driver Position)

  • 박지양;윤영한;곽영찬;손창기
    • 자동차안전학회지
    • /
    • 제10권3호
    • /
    • pp.32-37
    • /
    • 2018
  • Recently, the driver can be assisted by the advanced active safety devices such as ADAS from road traffic risks. With this system, driver and passenger may freed from can driving tasks or kept eyes on forward direction while on the road. Help from adoptive cruise control, auto parking and newly develped automated driving vehicles technologies, the driver positions will vary significantly from the current standard driver position during the travel time. On this hypothesis, the objective of this study is analyze the behavior and injuries of drivers in the event of frontal impact under these abnormal driver position. Based on the KNCAP frontal impact testing method, this simulation matrix was set-up with dummies of 5 th tile female Hybrid III dummy and 50 th tile male Hybrid III dummy. The small sedan type passenger car was modeled in this simulation. The series of simulation was performed to compare the injuries and behaviour of each dummy, varying the seating status and seat position of each dummy.

일 지역주민의 죽음관과 돌봄행위 (The Notion of Death and Caring Behaviors in one Community)

  • 고성희;이영희
    • 대한간호학회지
    • /
    • 제29권3호
    • /
    • pp.688-699
    • /
    • 1999
  • This study was to find out the perceptions of toward death and caring behavior of lay persons in one community : One Island in Puan County, Chonbuk. The methodology of this study was ethnography. For this study, the fieldwork was conducted from October 1997 to July 1998. Data collected by in-depth interview and participant observations. The participants consisted fo were 17 persons of both sexes. The key informants were four specific people. The result of this study is as follows ; The people perceived two different kinds of death. Normal death, which means death from old age. The person was respected as an ancestor God and was believed to exist forever with their offspring. Abnormal death was regarded as negative, many had fears toward this kind of death. The causes of abnormal death were supernatural phenomena and had absolute holy meanings. Whether death was good or bad, the death was not personal, but collective events as family or community affairs and was interpreted as death and birth for their offsprings. Funeral rites were family-centered and/or com munity-centered. They did normal procedures for normal deaths for abnormal deaths, there were many protective ceremonies(BuJungMagi : the prevention of the taboo of uncleanliness) for the remaining people. These ceremonies combined confucism and shamanism. Caring behavior for dying persons was ruled as community-centered, reciprocal and reality-centered principles.

  • PDF

민간종합검진 유소견자들의 치료기관 선택에 미치는 영향 (The Influence on Selecting the Medical Institute for Treatment by Patients Who Had Abnormal Findings through the Private Health Screening)

  • 정은주;황병덕
    • 보건의료산업학회지
    • /
    • 제5권4호
    • /
    • pp.1-13
    • /
    • 2011
  • The purpose of this study is to analyze the medical care utilization behavior of patients to whom treatment (surgery) is recommended after they are diagnosed with abnormal findings on health screening and factors affecting the selection of the medical institute for treatment. The data was collected from 291 patients who need treatment or surgery, according to the abnormal findings on the additional examination such as cardiac CT, brain MRI, Gastroscopy and Colonoscopy since four diseases are suspected among of 2,752 people who receive health screening. The results are as follows. First, the most common disease of patients who have abnormal findings by the diagnosis through the results of first testing is colon disease based on through the additional examination. The most common disease of patients who will get treatment (surgery) based on final diagnosis by a doctor who determines the result of health screening on the basis of diagnosis from the first testing is cardiovascular disease. Second, in terms of diseases, patients with cardiovascular disease select the medical institute where they get the health screenings as a place for treatment. Patients with cerebrovascular disease select another medical institute for treatment. Finally, the affective factors of selectivity treatment facility on health screening satisfaction were human, facility, health screening and revisit factors.

COVID-19 Pandemic and the Reaction of Asian Stock Markets: Empirical Evidence from Saudi Arabia

  • SHAIK, Abdul Rahman
    • The Journal of Asian Finance, Economics and Business
    • /
    • 제8권12호
    • /
    • pp.1-7
    • /
    • 2021
  • The study examines the influence of COVID-19 on the stock market returns of Saudi Arabia. The data was analyzed through event study methodology using daily price data of Tadawul All Share Index (TASI). The study examines the behavior pattern of the Saudi Arabian stock market in different phases during the event period by selecting six-event windows with a range of 10 days. The results report a negative Abnormal Return (AR) of -0.003 on the event date, while the abnormal returns reversed the next day to 0.005 positively. The result of Cumulative Abnormal Return (CAR) is negative and significant at the 1 percent level in all the six-event windows starting from the event date to day 59 after the event for the TASI index. Even though the influence of the COVID-19 pandemic decreased after 30 days of the event date, it increased during the last ten days of the event window. The stock market volatility of Saudi Arabia increased during the post-event period compared to the pre-event period with a negative mean return of -0.326 and a greater standard deviation. In a conclusion, the study found a significant influence of the COVID-19 pandemic on the stock market returns of TASI.