• 제목/요약/키워드: At-site frequency analysis

Search Result 338, Processing Time 0.027 seconds

A Study of Vibration Characteristics of Exposed Gas Pipeline under Vehicle Loading (차량 하중을 받는 노출 가스배관의 진동특성 연구)

  • 홍성경;김준호;정석영
    • Journal of the Korean Society of Safety
    • /
    • v.14 no.4
    • /
    • pp.71-77
    • /
    • 1999
  • Exposed gas pipeline in underground, especially subway construction site, has been continuously vibrated by vehicle above ground. Because this vibration can cause unexpected damages to pipeline, we had measured and analyzed the vibration. This paper presents results of the vibration analysis of exposed gas pipeline and the results are as follows. The major vertical vibration frequency of pipeline was about 13 Hz and the other frequency components disappeared when the vibration transmitted to I-beam and wire rope. Existence of wooden casement had not affect vibration of exposed gas pipeline. The results of modal analysis by experimental and analytical methods have good agreement and it is also shown that exposed pipeline has possibility of resonance at second mode.

  • PDF

Improving Patient Safety and Control in Operating Room by Leveraging RFID Technology

  • Su, Chuan-Jun
    • Industrial Engineering and Management Systems
    • /
    • v.8 no.1
    • /
    • pp.37-46
    • /
    • 2009
  • Patient safety has become a growing concern in health care. The U.S. Institute of Medicine (IOM) report "To Err Is Human: Building a Safer Health System" in 1999 included estimations that medical error is the eighth leading cause of death in the United States and results in up to 100,000 deaths annually. However, many adverse events and errors occur in surgical practice. Within all kinds of surgical adverse events, wrong-side/wrong-site, wrong-procedure, and wrong-patient adverse events are the most devastating, unacceptable, and often result in litigation. Much literature claims that systems must be put in place to render it essentially impossible or at least extremely difficult for human error to cause harm to patients. Hence, this research aims to develop a prototype system based on active RFID that detects and prevents errors in the OR. To fully comprehend the operating room (OR) process, multiple rounds of on site discussions were conducted. IDEF0 models were subsequently constructed for identifying the opportunity of improvement and performing before-after analysis. Based on the analysis, the architecture of the proposed RFID-based OR system was developed. An on-site survey conducted subsequently for better understanding the hardware requirement will then be illustrated. Finally, an RFID-enhanced system based on both the proposed architecture and test results was developed for gaining better control and improving the safety level of the surgical operations.

Characterization of the Spatial Distribution of Fracture System at the Rock Block Scale in the Granitic Area (화강암지역의 암반블록규모 단열체계 분포특성 연구)

  • 김경수;배대석;김천수
    • Tunnel and Underground Space
    • /
    • v.12 no.3
    • /
    • pp.198-209
    • /
    • 2002
  • To assess deep geological environment for the research and development of hish-level radioactive waste disposal, six boreholes of 3" in diameter were installed in two granitic areas. An areal extent of the rock block scale in the study sites was estimated by the lineament analysis from satellite images and shaded relief maps. The characterization of fracture system developed in rock block scale was carried out based on the acoustic televiewer logging in deep boreholes. In the Yuseong site, the granite rock mass was divided into the upper and lower zones at around -160m based on the probabilistic distribution characteristics of the geometric parameters such as orientation, fracture frequency, spacing and aperture size. Since the groundwater flow is dependent on the fracture system in a fractured rock mass, the correlation of the fracture frequency and cumulative aperture size to the hydraulic conductivity was also discussed.

Site-Directed Saturation Mutagenesis of Yeast Gcn4p at Codon 242

  • Lee, Jae-Yung;Bae, Yu-Byung;Kim, Jung-Ae;Song, Jae-Mahn;Choe, Mu-Hyeon;Kim, Ick-Young;Kim, Joon
    • Journal of Microbiology and Biotechnology
    • /
    • v.9 no.1
    • /
    • pp.122-125
    • /
    • 1999
  • Gcn4p, a transcriptional activator protein of the yeast, Sacchromyces cerevisiae, binds to the specific sequence in the promoters of many amino acid biosynthetic genes for general control. The serine residue (Ser 242) of Gcn4p directly contacts the DNA. Here, for inspecting the DNA binding properties and the level of transcriptional activation of Gcn4p, we introduced a polymerase chain reaction (PCR) site-directed saturation mutation library into the Ser 242 site using 2 outside primers and 2 oligonucleotides with its codons fully degenerated. The sequencing analysis of 146 samples revealed the even nucleotide distribution within the experimental error showing 23, 26, 25, and 26% frequency of U, C, A, and G bases, respectively. This method turned out to be a simple, fast, and economical method for constructing a library of all 20 amino acids at specific codon.

  • PDF

Computational Modelling Method by Using the Natural Frequencies of Five-Story Stone Pagoda in Chongnimsa Site (고유진동수를 이용한 정림사지 5층 석탑의 구조모델)

  • Lee, Sung-Min;Lee, Ki-Hak;Park, Sun-Woo;Suh, Man-Chul;Lee, Chan-Hee
    • Journal of Korean Association for Spatial Structures
    • /
    • v.8 no.5
    • /
    • pp.67-74
    • /
    • 2008
  • Multi-layered stone masonry monuments, such as stone pagoda can be modeled as a multi-degrees of freedom system. The dynamic behavior of these structures are mainly influenced by contour condition of contacting surface of stones. In this case the mass of the system can be easily estimated, mean while the estimation of stiffness at junction is not simple. In this paper a method for estimating the spring constant at the contacting surface of stone in proposed. This paper describes a method of computational modelling technique for structural analysis of stone pagodas using measurement of natural frequency and eigenvalue analysis. For this purpose Five story stone pagoda in Cchongnimsa site was selected as a model.

  • PDF

Effectiveness of multi-mode surface wave inversion in shallow engineering site investigations (토목관련 천부층 조사에서 다중 모드 표면파 역산의 효과)

  • Feng Shaokong;Sugiyama Takeshi;Yamanaka Hiroaki
    • Geophysics and Geophysical Exploration
    • /
    • v.8 no.1
    • /
    • pp.26-33
    • /
    • 2005
  • Inversion of multi-mode surface-wave phase velocity for shallow engineering site investigation has received much attention in recent years. A sensitivity analysis and inversion of both synthetic and field data demonstrates the greater effectiveness of this method over employing the fundamental mode alone. Perturbation of thickness and shear-wave velocity parameters in multi-modal Rayleigh wave phase velocities revealed that the sensitivities of higher modes: (a) concentrate in different frequency bands, and (b) are greater than the fundamental mode for deeper parameters. These observations suggest that multi-mode phase velocity inversion can provide better parameter discrimination and imaging of deep structure, especially with a velocity reversal, than can inversion of fundamental mode data alone. An inversion of the theoretical phase velocities in a model with a low velocity layer at 20 m depth can only image the soft layer when the first higher mode is incorporated. This is especially important when the lowest measurable frequency is only 6 Hz. Field tests were conducted at sites surveyed by borehole and PS logging. At the first site, an array microtremor survey, often used for deep geological surveying in Japan, was used to survey the soil down to 35 m depth. At the second site, linear multichannel spreads with a sledgehammer source were recorded, for an investigation down to 12 m depth. The f-k power spectrum method was applied for dispersion analysis, and velocities up to the second higher mode were observed in each test. The multi-mode inversion results agree well with PS logs, but models estimated from the fundamental mode alone show f large underestimation of the depth to shallow soft layers below artificial fill.

Study on Evaluation of Internal Leak of Turbine Control Valve in Power Plant Using Acoustic Emission Signal Measurement (음향방출 계측에 의한 터빈 제어밸브 내부누설 평가연구)

  • Lee, S.G.
    • Journal of Power System Engineering
    • /
    • v.12 no.5
    • /
    • pp.65-70
    • /
    • 2008
  • The purpose of this study is to verify availability of the acoustic emission in-situ monitoring method to the internal leak and operating conditions of the turbine major valves relating to safety for turbine operating and prevention of turbine trouble at nuclear power plants. In this study, acoustic emission tests are performed when the pressurized electro-hydraulic control oil flowed through turbine electro-hydraulic controller oil check valve and turbine power/trip fluid solenoid valve in the condition of actual turbine operating. The acoustic emission method was applied to the valves at the site, and the background noise was measured far the abnormal plant condition. To judge for the leak existence ell the object valves, voltage analysis and frequency analysis of acoustic signal emitted from infernal leak in the valve operating condition are performed. It was conformed that acoustic emission method could monitor for valve internal leak to high sensitivity.

  • PDF

Regional Low Flow Frequency Analysis Using Bayesian Multiple Regression (Bayesian 다중회귀분석을 이용한 저수량(Low flow) 지역 빈도분석)

  • Kim, Sang-Ug;Lee, Kil-Seong
    • Journal of Korea Water Resources Association
    • /
    • v.41 no.3
    • /
    • pp.325-340
    • /
    • 2008
  • This study employs Bayesian multiple regression analysis using the ordinary least squares method for regional low flow frequency analysis. The parameter estimates using the Bayesian multiple regression analysis were compared to conventional analysis using the t-distribution. In these comparisons, the mean values from the t-distribution and the Bayesian analysis at each return period are not significantly different. However, the difference between upper and lower limits is remarkably reduced using the Bayesian multiple regression. Therefore, from the point of view of uncertainty analysis, Bayesian multiple regression analysis is more attractive than the conventional method based on a t-distribution because the low flow sample size at the site of interest is typically insufficient to perform low flow frequency analysis. Also, we performed low flow prediction, including confidence interval, at two ungauged catchments in the Nakdong River basin using the developed Bayesian multiple regression model. The Bayesian prediction proves effective to infer the low flow characteristic at the ungauged catchment.

A Study on the Visibility Analysis Model for the Ward of General Hospital Considering Nurse's Circulation (종합병원 병동부 간호 이동 동선을 고려한 가시 특성 분석 모델에 관한 연구)

  • Kim, Seo-Yeong;Kweon, Jihoon
    • Journal of the Regional Association of Architectural Institute of Korea
    • /
    • v.20 no.6
    • /
    • pp.71-80
    • /
    • 2018
  • The path and visibility of nurses in general hospital wards have been treated as architectural planning factors. However, the analysis approach of existing studies shows limitations that only fixed physical elements are considered without considering the behavior of users using space. Consider factors for analysis of ward and models based on this study model. Select a case hospital to apply the analysis technique and conduct the nurse questionnaire and route survey of the hospital. Establish a framework for analysis model applied with the path of nurse movements. The analysis model applies to the case hospital. The analysis results are aggregated to derive design suggestion for reference to the spatial improvement of the ward. Visible visibility to observe the bedside in the nursing station, visibility to observe the beds in the nurse's path, and visibility to observe patients moving in the nurse's path were derived from visual access frequency and exposure frequency. The survey of nurses' movements at the site allowed the nurses to calculate the distance required to move. Reflecting the path of nurse movement, a model was presented for a comprehensive analysis of nursing distance and nursing visibility, which could lead to improvement in the observation and visibility of nurses and the layout of patient rooms or day rooms.

Near-field Performance Analysis of LW-TLM Antenna for propagation obstacle (장파대역 TLM 안테나의 전파 장애물에 의한 근거리장 성능 분석)

  • Kim, Young-Wan
    • Journal of IKEEE
    • /
    • v.24 no.4
    • /
    • pp.1064-1068
    • /
    • 2020
  • For LW-TLM antenna of 65 kHz, Near-field propagation characteristics due to wave propagation obstacle are analyzed in this paper. The simulation modeling for propagation effects are based on the model of actual LW-TLM antenna which utilizes the frequency of 65 kHz, and the model expressed as propagation obstacle at a mountain height and a proximity of antenna and mountain. The near-field performance are analyzed based on the parameters of simulation model. In case of a normal mountain height and distance between the adjacent mountain and antenna site, a field strength change of about 1.7 dB has occurred. Above the constant distance of propagation obstacle and antenna, the wave propagation characteristics of disregarding the effects of propagation obstacle are shown. The results of this paper can be used to design and build a transmitting antenna site with 65 kHz operating frequency.