• Title/Summary/Keyword: cross area

Search Result 3,122, Processing Time 0.027 seconds

Analysis of Actual Cross-Sectional Area During Scanning According to MRI Bore Size (MRI 보어 구경에 따른 검사 시 실효 단면적 분석)

  • Jeong, Hyunkeun;Jeong, Hyundo;Kim, Seongho;Jeon, Mincheol;Yoo, Sejong;Ko, Hyuncheol;Cho, Yonghyun
    • Journal of Biomedical Engineering Research
    • /
    • v.41 no.6
    • /
    • pp.219-227
    • /
    • 2020
  • In this study, we tried to quantify the actual cross-sectional area inside the bore when scanning by the MRI system with various bore sizes. To this end, a comparative analysis was conducted by both of blueprint of each MRI equipment and actual measurement in the field. As a result of analysis, ACSA(Actual Cross-Sectional Area) in Ingenia CX, Elition X, uMR 780, Omega, Vida, Lumina, Architect, Premier is recorded as 171230, 232150, 242100, 309332, 230760, 230760, 229380 and 235990 ㎟, respectively ACSA% was 60.6, 60.3, 73.0, 70.0, 60.0, 60.0, 59.6, and 61,3%. In addition, DTB (Distance from Table top to Bore top) recorded 400, 407, 445, 495, 405, 405, 405, 403, and 412 mm. Through this study, it was confirmed that there is a difference between the bore size according to each MRI system and the actual cross-sectional area during MRI scanning. Accordingly, if we consider the internal actual area just not bore size at the clinical site, useful diagnostic images can be obtained in the end with better convenience.

Cross Flow Characteristics of the Core Simulator in SMART Reactor Flow Distribution Test Facility (SMART 유동분포시험장치 노심모의기에서의 횡방향 유동 특성)

  • Yoon, Jung;Kim, Young-In;Chung, Young-Jong;Lee, Won-Jae
    • The KSFM Journal of Fluid Machinery
    • /
    • v.15 no.4
    • /
    • pp.5-11
    • /
    • 2012
  • To identify the flow characteristics of the SMART reactor, a flow distribution model test and a numerical simulation are performed in KAERI. Among several part of the SMART reactor, the fuel assemblies are simulated using simulators because of the complexity. The geometries of the core in the SMART reactor and simulator are different, but some similarities are maintained such as the ratio of pressure drop in the vertical and cross directions. There are cross flow holes in each core simulator to reproduce the cross flow of SMART fuel assemblies. To know the flow characteristics of the cross flow, numerical analysis is performed. As the cross flow area is decreased, the pressure drop between inlet and outlet is decreased. Also, when the flow imbalance between two core simulators is constant, the cross flow area does not significantly affect the cross flow.

Image Analysis of the Luster of Fabrics with Modified Cross-section Fibers

  • Shin Kyung In;Kim Seong Hun;Kim Jong Jun
    • Fibers and Polymers
    • /
    • v.6 no.1
    • /
    • pp.82-88
    • /
    • 2005
  • We have investigated the luster of modified cross-sectional fiber fabrics as one of the essential quality estimates for clothing development. We have confirmed an objective evaluation method, and have determined the experimental luster char­acteristics of modified cross-section fibers. The cross-section of the fibers in a fabric affects the appearance of a textile. We used the image analysis method to investigate the luster to determine the critical factors influencing the appearance of modi­fied cross-section fiber fabrics. For similarly structured textiles in a component fabric, clear differences were observed in the fabric weave, density, percentage, and total area of blobs, which is image region. Color played a decisive role in the luster of the textiles, and luster was not significantly influenced by the modified cross-section fabric weave. In addition, the degree of luster did not increase in the order plain to twill to satin for modified cross-sectional fiber fabrics. All the split-type microfi­bers exhibited higher numerical luster values (percentage of pixels, and number and total area of blobs) than sea-island microfibers did. The degree of luster of the modified cross-sectional fiber fabrics was not high at specular reflection angles.

Stability Analysis ofn HTS Current Lead with Constant Safety Factor (안전율이 일정한 초전도 전류도입선의 안정성해석)

  • Seol, Seoung-Yun
    • Progress in Superconductivity and Cryogenics
    • /
    • v.2 no.2
    • /
    • pp.15-19
    • /
    • 2000
  • The stability of variable cross-sectional area HTS current lead is considered. The cross-sectional area is varied to have a constant safety factor which is defined as the ratio of operating current and critical current of superconductor. As the constant area HTS lead, the variable cross-sectional area HTS lead also has three steady states above the bifurcation point and only one steady state below the bifurcation point. The temperature profiles and current sharing ratios for each steady state are calculated. The heat dissipation into cryogenic system for super-conducting, intermediate, and upper states are compared. For Bi-2333 sheathed with silver-gold alloy 2m length of current lead, and the maximum temperature of upper state seems to be burn-out free below 5m length.

  • PDF

Effect of Tube Area on the Impulse Wave Discharged from the Exit of Tube (관출구로부터 방출되는 펄스파에 미치는 관단면적의 영향)

  • Shin, Hyun-Dong;Lee, Young-Ki;Kim, Heuy-Dong
    • Proceedings of the KSME Conference
    • /
    • 2003.11a
    • /
    • pp.544-549
    • /
    • 2003
  • When a shock wave arrives at an open end of tube, an impulse wave is discharged from the tube exit and causes serious noise and vibration problems. In the current study, the effect of the cross-sectional area of tube on the impulse wave is numerically investigated using a CFD method. The Harten-Yee's total variation diminishing(TVD) scheme is used to solve the axisymmetric, two-dimensional, unsteady, compressible Euler equations. With three different cross-sectional areas of tube, the Mach number of the incident shock wave $M_{s}$ is varied between 1.01 and 1.5. The results obtained show that the directivity and magnitude of impulse wave strongly depend upon the Mach number of incident shock wave and are influenced by the tube area. It is also known that the tube cross-sectional area significantly affects the magnitude of impulse wave at or near the tube axis.

  • PDF

Computation of Ease-Rate in Basic Bodice Pattern by Analysis of Multiple Cross Section, Using 3-D Measuring Instrument (착의 단면 중합도 분석에 의한 길 원형의 여유률 산출 - 3차원 형상 계측기에 의한 -)

  • Shim, Kue-Nam;Kim, Jin-Sun;Lee, Womn-Ja
    • Fashion & Textile Research Journal
    • /
    • v.2 no.4
    • /
    • pp.360-365
    • /
    • 2000
  • This research is the trial for the computation of the ease-rate for the bodice pattern. The result of the analysis about the cross section figures of garment space by using a 3-D measuring instrument is that: The garment space of each bodice by each body size is definite. In the figure of cross section of the basic lines, an area of cross section of garment space and length of cross section of garment space are not increased in proportion to an area of cross section of the body. The ease rate is the same no matter that flat-rate of the body is same or different. The ease-rate is computed by length of cross section of garment space that is in proportion to the radius of the body.

  • PDF

Effect of Short-term Undernutrition on Hindlimb Muscles in Rats (단기간의 영양 섭취 저하가 쥐 뒷다리근에 미치는 영향)

  • Choe, Myoung-Ae;Lee, Kyoung-A;An, Gyeong-Ju
    • Journal of Korean Biological Nursing Science
    • /
    • v.13 no.2
    • /
    • pp.179-184
    • /
    • 2011
  • Purpose: The purpose of this study was to examine the effect of short-term undernutrition on muscle weight and Type I and II fiber cross-sectional area of hindlimb muscles in undernourished rats. Methods: Adult male Sprague-Dawley rats were randomly assigned to one of two groups: The undernourished (UN) group (n=9) and the control (C) group (n=9). A control group was allowed to have water and pellet ad libitum for 5 days. Undernutrition was induced by providing 32% of total intake of the control group for 5 days. Body weight of two groups and food intake of the control group were measured every day. At 6 days all rats were anesthetized and soleus, plantaris and gastrocnemius muscles, and liver were dissected. Body weight, food intake, muscle weight, liver weight and cross-sectional area were determined. Results: The UN group at 6 days after undernutrition showed significant decreases, as compared to the control group in body weight, liver weight, muscle weight of soleus, plantaris, and gastrocnemius, and Type I fiber cross-sectional area of soleus and gastrocnemius muscles and Type II fiber cross-sectional area of plantaris and gastrocnemius muscles. Conclusion: Hindlimb muscle atrophy occurs from the short-term undernutrition.

A Computational Study of the Impulsive Wave Discharged from a Circular Tube (원형관으로부터 방출되는 펄스파에 대한 수치해석적 연구)

  • Lee, Young-Ki;Kweon, Yong-Hun;Kim, Heuy-Dong
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.28 no.7
    • /
    • pp.850-856
    • /
    • 2004
  • When a shock wave arrives at the open end of a tube, an impulsive wave is discharged from the tube exit and causes serious noise and vibration problems. In the current study, the effect of the cross-sectional area of a circular tube on the impulsive wave is investigated using computational methods. Marten-Yee's TVD scheme was employed to solve axisymmetric, unsteady, compressible Euler equations. With a change in the cross-sectional area of the tube, the Mach number of an incident shock wave is varied between 1.01 and 1.50. The results obtained show that the magnitude of the impulsive wave strongly depends upon the Mach number of the incident shock wave and the cross-sectional area of the tube. It is also found that for a given cross-sectional area of the tube, the impulse wave has strong directivity to the tube axis.

Analysis of Age-related Distribution of the Tracheal Diameter and Cross-sectional Area Among Koreans -Compuerized Tomographic Measurement- (한국인의 연령별 기관 내경 및 단면적 분포에 대한 분석 -흉부전산화단층촬영을 이용한 측정-)

  • Lee, Gun;Kim, Dae-Sik;Moon, Seung-Chul;Koo, Won-Mo;Yang, Jin-Young;Lee, Hyeon-Jae;Lim, Chang-Young;Han, Hyeon;Kim, Kwang-Ho;Sun, Kyung
    • Journal of Chest Surgery
    • /
    • v.32 no.5
    • /
    • pp.442-447
    • /
    • 1999
  • Introduction: Understanding the normal distribution of the tracheal diameter and crross- sectional area is one of the key elements in the management of various tracheal pathologies or tracheal reconstruction for the patients in growing age. However, data for Korean standard has been lacking. This study was designed to analyze retrospectively the distribution of tracheal diameter and cross-sectional area in young Koreans, which can afford fundamental data for the management of tracheal diseases. Material and Method: Of the patients who underwent computerized tomogram of the chest between May 1996 and August 1998, one hundred six young patients(age range: 0-20 years) were included. Patients with any conditions which might affect the tracheal cross-sectional area or diameter, such as tracheal disease, previous operation, mediastinal tumor, or obstructive lung disease were excluded from the study. Gender distribution was 69 males and 37 females. Tracheal diameters, anterior-posterior and transverse, were measured at the level of the thoracic inlet(level I) and the aortic arch(level II). Types of the trachea were divided into round, oval, or horseshoe shaped on cross-sectional view, and the dimension was calculated by using the equation of A=1/4$\pi$ab(A; area, $\pi$; 3.14, a; anterior-posterior diameter, b; transverse diameter). We analyzed the distribution of the diameter at each level and compared the cross-sectional area with respect to age and gender. A p-value lower than 0.05 wa considered significant. Result: The trachea of patients less than 5 years old were round in shape at both of level I and II, and no differences in cross-sectional area was observed between the levels(p=NS). As the age increased, the trachea become oval in shape at level I while it remained round in shape at level II(p=0.020). The tracheal diameter and cross-sectional area increased as the age increased with a linear correlation(r>0.9). In patients less than 5 years of age, female patients showed larger cross-sectional area than male patients (p=0.020), and it was reversed in patients older than 15 years of age(p=0.002). Conclusion: From the above results, we suggest chest computerized tomogram as a safe and reliable tool in measuring the tracheal diameter and cross-sectional area. We also provide the data as a standard for distribution of the tracheal diameter and cross-sectional area in young Korean population.

  • PDF

Investigation of Microbial Contamination and Working Environment in University Foodservices (대학급식소 작업시설과 환경의 미생물 오염도 분석 및 작업환경 실태조사)

  • Park, Soon-Hee;Moon, Hye-Kyung
    • Journal of the Korean Dietetic Association
    • /
    • v.23 no.2
    • /
    • pp.180-191
    • /
    • 2017
  • The purpose of this study was to identity the probability of cross-contamination from the environment. For this, we examined foodservices at 20 universities/colleges for microbiological analysis of their working facilities and environment as well as their preventive equipment against cross-contamination. Seventy percent of the 20 foodservices were found to maintain one unified working area, which suggests high probability of contamination of food/utensils/equipment in the cooking area by pre-preparation or dish washing. According to the microbiological analysis, the hygiene acceptance ratio of working facilities in the clean zone was 70%, which was higher than the average 45% hygiene acceptance ratio of working facilities in the contamination operating zone. There was a significant difference in the total plate count (P<0.001) and coliform count (P<0.01), which demonstrates that work tables in the clean zone were in a good state compared to those in the contamination operating zone. In the contamination operating zone, refrigerator shelves had a high probability of cross-contamination. Regarding the floor surface and airborne microbes, cooking areas which should be maintained as clean zones had higher cross-contamination probability than those in the contamination operating zone. So corrective actions such as cleaning and sanitizing, keeping dry floors, lowered temperature and humidity, shoe disinfecting facilities, and checking concentrations, are necessary to manage floor surfaces and airborne microbes in the cooking area.