• 제목/요약/키워드: Adjusted rating time

검색결과 9건 처리시간 0.019초

원심펌프 베어링 유닛의 열신뢰성 분석 (Thermal Reliability Analysis of the Bearing Units in a Centrifugal Pump)

  • 문정환;문승재;이재헌
    • 설비공학논문집
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    • 제19권4호
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    • pp.313-320
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    • 2007
  • In this paper, the experimental study has been carried out to investigate the reliability lifetime of two bearing units based on the oil temperature. Measurements for the oil temperature as well as the bearing temperature during normal operation were performed to study the effects of oil viscosity and oil submergence percentages in the two bearing units. The optimal lubrication condition to increase the lifetime of the bearing unit A was found that its viscosity and submergence percentage were VG32 and 25%, respectively. For the bearing unit B, when the oil viscosity and submergence percent were VG32 and 75%, the lubrication condition was the most efficient. Finally, the adjusted rating times of both the bearing units were calculated to be over 28,000 h, which is greater than the minimum adjusted rating times of 25,000 h. Therefore, they satisfied the regulated lifetime of API 610.

Quality Characteristics of Chicken Breast Surimi as Affected by Water Washing Time and pH Adjustment

  • Jin, Sang-Keun;Kim, Il-Suk;Choi, Yeung-Joon;Park, Gu-Boo;Yang, Han-Sul
    • Asian-Australasian Journal of Animal Sciences
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    • 제21권3호
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    • pp.449-455
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    • 2008
  • This study was carried out to compare the quality properties of chicken breast surimi manufactured by four different procedures/methods. Surimi was made from chicken breast by washing two (T1) or four times (T2) with water as well as by pH adjustments at 3.0 (T3) or 11.0 (T4). The contents of moisture and crude fat were significantly higher in the surimi manufactured from pH-adjusted material than after washing. Again, collagen and yield were significantly higher in chicken breast surimi manufactured from washed than pH-adjusted samples, whereas crude protein was higher in the pH-adjusted than washed surimi samples. There was no significant difference in myofibrillar protein content among the surimi manufactured after different washing times and differences following pH adjustments were found. T4 showed highest myofibrillar protein content rating among the surimi samples. All physical characteristics were higher in pH-adjusted chicken breast surimi than in T1 and T2 washed surimi samples. The pH-adjusted surimi had higher hardness, gumminess and chewiness than washed surimi samples (p<0.05). The chicken breast surimi made by pH adjustments had higher lightness (L*) than when made by washing times, whereas pH 3.0-adjusted surimi samples had lower whiteness (W) then the other surimi samples. Myoglobin content was significantly higher in the surimi manufactured from pH-adjusted chicken breast samples.

앉은 자세에서 일어서기(Sit to stand)과제의 동작시간과 지면반발력 분석 (The Analysis of Movement time and Ground Reaction Force during Sit to Stand Task in Healthy)

  • 김수민
    • PNF and Movement
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    • 제9권1호
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    • pp.31-38
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    • 2011
  • Purpose : Sit-to-stand (STS) is one of the important activities of daily living (ADL) and each of its parameters is used frequently. This study aimed to examine the influence of different seat height on performance time and floor reaction force strength during an STS movement. Methods : Fifteen young-adult male subjects participated in this study. The subjects were divided into three groups based on lower leg length. Subjects performed an STS movement twice from chairs at height adjusted by the lower leg length of each subject. To examine the influence of the chair seat height, ground reaction forces during a STS performed with 3 chair heights adjusted to each subjects lower leg length were compared. Results : Vertical ground reaction force and time during an STS movement were measured to evaluate. Parameters regarding ground reaction force were selected for analyses. Significant differences were found in ground reaction force at G1 was greater than G2 and G3. Conclusion : The STS movement achievement strategy differed since chair seat height changes relatively by the difference in lower leg length. When conducting the ability to achieve STS movement rating test, chair seat height considering each subject's lower leg length may be needed.

아산화질소(N2O)와 공기(Air)를 사용한 마취 수술의 기낭압 조정이 수술 후 인후통과 쉰목소리에 미치는 영향 (The Effect of Intracuff Pressure Adjustment on Postoperative Sore Throat and Hoarseness after Nitrous Oxide and Air Anesthesia)

  • 구안나;유미
    • 대한간호학회지
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    • 제49권2호
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    • pp.215-224
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    • 2019
  • Purpose: To investigate the differences in postoperative sore throat and hoarseness by adjustment of endotracheal tube cuff pressure (CP) during nitrous oxide ($N_2O$) and air anesthesia. Methods: A one-equivalent control group pretest-posttest design was used. Data were collected from August 8 to October 19, 2017 and analyzed using the independent t-test and repeated measures ANOVA. Eighty-four participants were enrolled and divided into three groups: 28 in the Control Group (CP adjusted every 30 minutes using $N_2O$), 28 in Experimental Group 1 (CP adjusted every 10 minutes using $N_2O$), and 28 in Experimental Group 2 (non-adjusted CP using air), all of whom underwent urologic, gynecologic, and orthopedic surgeries at the G University hospital. Sore throat was assessed using a numeric rating scale; hoarseness was evaluate using the Stout classification at 1, 6, and 24 hours after surgery. Results: Scores for sore throat and hoarseness were significantly different between the groups at each measurement time, and scores were consistently higher in the control group. During subsequent measurements, sore throat and hoarseness scores were significantly lower at 6 hours. Cuff pressure changed significantly using air anesthesia (${\chi}^2=10.41$, p=.015) up to 2 hours after induction. Severe sore throat and hoarseness was observed for up to 6 hours after surgery. Conclusion: Cuff pressure adjustment at short time intervals would be helpful in reducing postoperative sore throat and hoarseness. Nursing intervention focused on prevention of sore throat and hoarseness should be required up to 6 hours postoperatively in patients undergoing endotracheal intubation.

The Relationship between Hair Zinc and Lead Levels and Clinical Features of Attention-Deficit Hyperactivity Disorder

  • Shin, Dong-Won;Kim, Eun-Ji;Oh, Kang-Seob;Shin, Young-Chul;Lim, Se-Won
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제25권1호
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    • pp.28-36
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    • 2014
  • Objectives : The goal of this study was to examine the association between zinc and lead level and symptoms of attention-deficit hyperactivity disorder (ADHD) among Korean children. Methods : A total of 89 clinic-referred children participated in the study (ADHD group=45, control group=44). The participants were 5-15 years old, and were mainly from urban areas of Seoul, Korea. ADHD was diagnosed using the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version. We excluded children with a comorbid psychiatric disorder, medical illness requiring medication, or a prior history of taking ADHD medication. In order to evaluate the severity of ADHD symptoms, parents' Korean ADHD Rating Scale (K-ARS) was used. The ADHD diagnostic system (ADS) was used for evaluation of the severity of inattention and impulsivity. All participants completed the intelligence test and hair mineral analysis. Multiple regression analysis was used to examine the effect of hair zinc and lead levels on the K-ARS and ADS. We measured the predictive ability of the zinc and lead levels using logistic regression analysis. Results : The lead level explained the score for omission errors, commission errors, and response time SD in visual ADS in the ADHD group (adjusted $R^2$=.243, p<.01, adjusted $R^2$=.362, p<.01, and adjusted $R^2$=.275, p<.01), the score for omission errors of auditory ADS in ADHD group (adjusted $R^2$=.407, p<.01) and the entire group (adjusted $R^2$=.292, p<.01). Zinc was significantly explanatory for the K-ARS scores for the entire group (adjusted $R^2$=.248, p<.001) and the ADHD group (adjusted $R^2$=.247, p<.05). Conclusion : These findings suggest a possible role of zinc and lead in ADHD. Lead concentration in hair samples affected the ADS scores, and this was more prominent in children with ADHD. Children with ADHD had a lower zinc concentration in their hair, and the zinc concentration in hair showed negative correlation with the K-ARS score.

디지털 사진매핑에 의한 공학적 암반분류와 터널의 보강 (Supporting The Tunnel Using Digital Photographic Mapping And Engineering Rock Classification)

  • 김치환
    • 터널과지하공간
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    • 제21권6호
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    • pp.439-449
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    • 2011
  • 터널의 페이스매핑(face mapping)을 신속하고 신뢰성 있게 수행하기 위하여 디지털 사진으로부터 3차원 좌표의 점군(point cloud)을 생성하고 이로부터 절리면의 방향과 간격 및 암질지수(R.Q.D), 절리면 거칠기 등을 분석하였다. 분석결과를 공학적 암반분류 방법인 RMR(Rock Mass Rating)과 Q 시스템에 입력하여 보강방법을 결정하고 터널을 시공하였다. 그 결과 터널 페이스매핑 작업의 안전성을 높이면서, 분석부터 보강작업까지의 시간을 절약하였다. 또 터널 막장면의 디지털 영상과 공학적 암반분류용 정보를 객관적으로 평가하고 필요 시재분석이 가능하도록 보존함으로써 보강등급 결정과 터널보강 방법의 신뢰도를 높였다.

250W MHL용 Buck Type 전자식 안정기 및 Dimming 시스템 개발 (The Development of Buck Type Electronic Ballast for 250W MHL and Dimming System)

  • 박종연;박영길;정동열;김한수
    • 전력전자학회논문지
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    • 제7권1호
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    • pp.30-40
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    • 2002
  • 본 논문은 250w 메탈 할라이드 램프용 전자식 안정기의 개발에 관한 연구로써 안정기의 입력 역율은 PFC IC를 이용하여 개선하였고, 벅 Type의 DC-DC 컨버터를 회로에 삽입하여 인버터회로에서 램프의 정격전압만을 공급할 수 있도록 함으로써 인버터 스위칭소자의 스트레스를 줄이게 되었다. 인버터의 형태는 풀 브릿지로 하였고 램프 점등을 구형 저주파에 고주파 성분을 첨가하는 방식으로 음향공명현상을 제거하였다. 또한 LC 회로를 이용한 간단 한 점화기 회로를 개발하였다. 벅 컨버터의 출력 전압을 조절하여 램프의 전압이 가변되는 원리를 이용하여 조광 제어를 할 수 있으며 계절별 및 시간대별로 점등시간과 조도조절이 가능토록 하였다. 벅 컨버터 출력 전압의 조절과 무부하 보호 및 과전류 보호 기능은 마이크로프로세서의 프로그램을 개발하여 수행하였다.

무용요법이 노인의 신체적.심리적 특성에 미치는 효과 (The Effect of Dance Therapy on Physical and Psychological Characteristics in The Elderly)

  • 이영란
    • 대한간호학회지
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    • 제29권2호
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    • pp.429-444
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    • 1999
  • This study was performed to explore the effects of a dance therapy on physical and psychological characteristics in the elderly. The design of this study was a non-equivalent pre-post test experiment. The subjects consisted of elderly persons living in a facility located in Suweon and Bucheon. Fifty eight subjects, aged between 65 and 93 years who had normal cognition, sensory function, balance, and resting blood pressure. They underwent tests of balance, flexibility, muscle strength, depression, and anxiety as baseline data before dance therapy, and at 6th week and at the end of the 12nd week after following dance therapy. Twenty seven elderly persons were assigned to the experimental group and participated with the dance therapy between April and July, 1998. The dance therapy was developed by the author with the help of a dance therapist and a physiatrist. This therapy was based on the Marian Chace's dance therapy and Korean traditional dance with music. The dance therapy consists of 50 minutes session, 3 times a week for 12 weeks. One session was consisted of warming-up, expression, catharsis, sharing, and closing stage. The intensity of the dance therapy was at the 40 % of age-adjusted maximum heart rates. Data were analysed with mead standard deviation, Chi-square test, unpaired t-test, repeated measures ANOVA, and Bonferroni multiple regression using SAS program. 1. The results related to the physical characteristics were as follows : 1) The balance (standing on one leg, walking on the balancing bar), flexibility and muscle strength (knee extensor, knee flexor, ankle plantarflexor and dorsiflexor) of the experimental subjects significantly increased over time mere than that of the control subjects. 2) The experimental group had significantly higher score for balance, flexibility, muscle strength of knee extensor, and knee flexor than the control group at the 12nd week after dance therapy. 3) The experimental group had significantly higher score for muscle strength of ankle dorsiflexor and plantarflexor than the control group at the 6th week and the 12nd week after dance therapy. 2. The results related to psychological characteristics were as follows : 1) Scores of Geriatric Depression Scale, Hamilton Depression Rating Scale, and Zung's Self-rating Anxiety Scale of the experimental group were significantly decreased over time more than that of the control group. 2) The experimental group had significantly lower score for depression than the control group at the 12nd week after dance therapy. 3) The experimental group had significantly lower score for anxiety than the control group at the 6th week and the 12nd week after dance therapy. The findings showed that the dance therapy could be effective in improving the balances, flexibility, and muscle strength of lower limb, and effective in decreasing the depression and anxiety of the elderly. Additional merits of the dance therapy would be inexpensiveness, easy accessibility, and increasing interpersonal relationship. It can be suggested that the dance therapy is effective in the health promotion of the elderly.

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불산 누출사고에 따른 지역사회 구성원들의 노출평가 (Exposure Assessment on Sub-Populations of the Local Community following a Hydrofluoric Acid Accident)

  • 김순신;우극현;윤성용;임현술;김근배;유승도;조용성;이석용;이현수;양원호
    • 한국환경보건학회지
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    • 제41권1호
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    • pp.1-10
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    • 2015
  • Objectives: The purpose of this study was to propose an indirect exposure assessment method using a questionnaire survey at a time when direct exposure assessment would be impossible after a chemical accident. Methods: About two weeks after an accident, a questionnaire survey was performed with 1,264 persons from the local community. Variables related to exposure were extracted from the survey contents, weighted and then graded for comparison with subjective symptoms in order to evaluate the extent of exposure. Survey items suitable for reflecting the previous exposure level during the accident were extracted, weighted and divided into quartile ranges. Subjective symptoms showed an increasing tendency with higher exposure level when compared with final exposure level (p<0.01). Results: For the relationship between the final exposure grade and subjective symptoms, as the exposure grade was increasing the rates complaining of symptom also showed an increasing tendency. However, when adjusted for demographic characteristics, there was a tendency for the eye irritation symptom to appear higher in women, and respiratory organ irritation appeared higher in smokers. Conclusions: When the problem of recall bias is considered, this study may not have completely unraveled exposure and the characteristics of the participants can affect subjective symptoms. Nevertheless, the exposure rating method of using a questionnaire showed a significant relationship with symptom level. It can be deemed that assessment of past exposure may be successfully evaluated by questionnaire in cases such as chemical accidents.