• Title/Summary/Keyword: Frequency analyzer

Search Result 617, Processing Time 0.027 seconds

Rheological and Pasting Properties of Potato Flour Dispersions (감자가루 분산액의 유변학적 및 페이스팅 특성 분석)

  • Heo, Hyemi;Won, Chuin;Jin, Yong-Ik;Chang, Dong-Chil;Kim, Misook;Lee, Youngseung;Chang, Yoon Hyuk
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.44 no.9
    • /
    • pp.1407-1413
    • /
    • 2015
  • The objective of this study was to investigate the rheological and pasting properties of potato flour dispersions at different concentrations (3, 4, 5, 6, and 7%, w/w). A potato cultivar 'Goun', used in this study, was developed by Highland Agriculture Research Center, RDA. Potato flour dispersions showed shear-thinning behaviors (n=0.44~0.51) at $25^{\circ}C$. Apparent viscosity (${\eta}_{a,100}$), consistency index (K), and yield stress (${\sigma}_{oc}$) significantly increased with an increase in potato flour concentration. Storage modulus (G') and loss modulus (G") significantly increased, whereas complex viscosity (${\eta}^*$) was significantly reduced with increasing frequency (${\omega}$) from 0.63 to 63.8 rad/s. Magnitudes of G' and G" were significantly increased with elevation of potato flour concentration. G' values were considerably greater than G" over the entire range of frequency (${\omega}$) with a high dependence on ${\omega}$. Cox-Merz rule was not applicable to potato flour dispersions. Rapid Visco Analyzer data showed that peak viscosity, trough viscosity, breakdown viscosity, final viscosity, and set back viscosity of samples significantly increased with an increase in potato flour concentration.

Prediction of EFT/B Signal Transfer Characteristics in Mobile Charging Circuit (모바일 충전회로에서 EFT/B 신호의 전달특성 예측에 대한 연구)

  • Song, SeungJae;Kim, Kwangho;Jo, Jeongmin;Lee, Seungbae;Kim, So-young;Nah, Wansoo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.26 no.10
    • /
    • pp.895-906
    • /
    • 2015
  • This paper presents a methodology and a model that can analyze the high frequency transfer characteristics from socket in the AC power port to the 5 V DC output port in the mobile charging circuit. This is to predict the output signals coming from the IEC(International Electrotechnical Commission) Standard(IEC 61000-4-4), EFT/B(Electric Fast Transient and Burst) immunity test for mobile charging circuit. Since the mobile charging circuit is energized from the AC power socket from the power line, it is necessary to know the high frequency transfer characteristics with activated AC power line. A simple CDN(Coupling-Decoupling Network) is designed and manufactured for measuring S-parameters of mobile charging circuit with and without AC power line activated. The result shows that the S-parameters of the specific mobile charging circuits are almost the same, independent of AC power line activation. Consequently, the S-parameters without AC line could be used to predict the output response to the EFT/B signals, and it was shown that the proposed methodology predicts the output responses quite accurately, which proves the validness of the methodology presented in this paper.

Perception of Body Weight Control, Life Styles, and Dietary Habits according to the Obesity Index(OI) of Female College Students (여자 대학생의 비만도에 따른 체중 조절 인식, 생활 습관 및 식습관 연구)

  • Ahn, Bo-Ra-Mi;Park, Eun-Sook
    • Korean Journal of Human Ecology
    • /
    • v.18 no.1
    • /
    • pp.167-179
    • /
    • 2009
  • This study aims at examining perception of body weight control and lifestyles and food habits of under-weight, normal-weight and over-weight female college students. The data analysis were conducted by a body fat analyzer and questionnaires. The subjects were 368 female college students divided into three groups: the under-weight(UW), the normal-weight(NW), and the over-weight(OW), according to the guidelines of the Korean Society for the Study of Obesity(2000). Among the subjects, 18.2% were under-weight, 63.6% normal-weight, and 18.2% over-weight. Mean of body weights were 45.4kg, 53.3kg, and 63.7kg, and BMIs were $17.5kg/m^2$, $20.5kg/m^2$ and $24.6kg/m^2$ in the UW, NW, and OW groups, respectively. 'Self assessment of body weight' was significant at the level of p<0.001 according to the Obesity Index. Of the UW group, 41.8% considered their weight to be normal and 4.5% believed they are over-weight. In the NW group, 43.2% thought they are over-weight, 1.5% believed they are under-weight. 57.1 % of the UW group and 98.6% of the NW group had ever tried to reduce their weight. Their 'exercise frequency and exercise time' were not significant by the 01. 'Regularity in the daily life' of the subjects was significant at the level of p<0.05. 43.3 % of the OW group answered that they don't live regular daily lives. 'Sleeping time' of the subjects was significant at the level of p<0.05 by the 01. 41.8% of the OW group reported that they sleep 'between 7 and 8 hours a day' which was the highest rate among the three groups. 'Frequency of meals per day' was not significant by the OI. 'The speed of eating meals' was significant at p<0.01, 23.9% of the UW group, 31.2% of NW group, and 38.8% of OW group reported that they have meals 'in a very fast speed'. Concludingly, most of female college students conceive themselves as having inappropriate body image, which means that they need to be given additional education about nutrition and diet.

Association between Interleukin 31 Receptor A Gene Polymorphism and Schizophrenia in Korean Population

  • Ban, Ju-Yeon;Kim, Su-Kang;Kim, Hak-Jae;Chung, Joo-Ho;Kim, Tae;Park, Jin-Kyung;Park, Hyun-Kyung;Kim, Jong-Woo
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.12 no.4
    • /
    • pp.205-209
    • /
    • 2008
  • Recently, Sun et al (2008) reported that the IL6R polymorphism is associated with schizophrenia. Therefore, to detect the association between polymorphisms of interleukin 31 receptor A (IL31RA) and schizophrenia, we genotyped 9 SNPs [rs9292101 (intron 1), rs1009639 (exon 2, Pr043Pro), rs2161582 (intron 2), rs68761890 (intron 5), rs16884629 (intron 6), rs11956465 (intron 12), rs12153724 (intron 12), and rs16884641 (intron 14)] using the Golden Gate assay on Illumina BeadStation 500 GX. Two hundred eighteen patients with schizophrenia and 379 normal subjects were recruited. Patients with schizophrenia were diagnosed according to DSM-IV, and control subjects without history of psychiatric disorders were selected. We used SNPStats, Haploview, HapAnalyzer, SNPAnalyzer, and Helixtree programs for the evaluation of genetic data. Of nine polymorphisms, three SNPs (rs9292101, rs1009639, and rs11956465) were associated with schizophrenia. The rs9292101 and rs11956465 showed significant associations with the risk of schizophrenia in the codominant [rs9292101, odds ratio (OR)=0.74, 95% confidence interval (CI)=0.58${\sim}$0.95, p=0.017] and recessive (rs11956465, OR=0.64, 95% CI=0.42${\sim}$0.96, p=0.034) models, respectively. The rs1009639 also was statistically related to schizophrenia in both codominant (OR=0.76, 95% CI=0.60${\sim}$0.97, p=0.025) and dominant (OR=0.66, 95% CI=0.44${\sim}$0.98, p=0.035) models. Two linkage disequilibrium (LD) blocks were made. In the analysis of haplotypes, a haplotype (GCT) in block 1 and a haplotype (CCACAG) in block 2 showed significant associations between schizophrenia and control groups (haplotype GCT, frequency=0.509, chi square=4.199, p=0.040; haplotype CCACAG, frequency=0.289, chi square=5.691, p=0.017). The results suggest that IL31RA may be associated with risk of schizophrenia in Korean population.

Cavity-type Beam Position Monitors for Future Accelerators (차세대 가속기용 공동형 빔위치 측정기 개발)

  • Kim S.H.;Park Y.J.;Hwang W.H.;Huang J.Y.;Honda Y.;Inoue Y.
    • Journal of the Korean Vacuum Society
    • /
    • v.15 no.4
    • /
    • pp.331-337
    • /
    • 2006
  • Cavity-type beam position monitors were developed in collaboration with KEK to use for the future accelerators such as international linear collider (ILC) or x-ray free electron laser (XFEL) in PAL. BPM components such as BPM cavity, beam tubes, waveguides and feedthroughs were assembled by brazing at the same time to reduce mechanical errors during the fabrication. There are four screwed pins around outer rim of the cavity for the tuning of cavity frequency and x-y isolation. The resonance frequency of BPM is 6.422 GHz, the inner diameter of cavity is 53.822 mm, and the range of mechanical adjusting is $+ / - 250{\mu}m$. The x-y isolation was measured better than -40 dB after tuned. Test results of signal forms, x-y isolations, sensitivities are satisfied within requirements for the KEK ATF2 beam line.

Performance Evaluation of a W-Band Waveguide Noise Measurement System for Calibrating Noise Sources (잡음원 교정용 W-대역 도파관 잡음 측정 시스템의 성능 평가)

  • Kang, Tae-Weon;Kim, Jeong-Hwan;Kwon, Jae-Yong;Kang, Jin-Seob
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.24 no.2
    • /
    • pp.180-188
    • /
    • 2013
  • A W-band waveguide noise measurement system for calibrating noise sources was implemented and its basic characteristics were discussed. The measurement system consists of a commercial noise figure analyzer, a full W-band frequency converter, and a local oscillator. To measure the noise temperature of a noise source, the Y-factor method is generally used. Since the Y-factor method is based on the assumption that the receiving system is linear, linearity is one of important performance parameters of the measurement system. In this paper, the linearities for mixer, intermediate frequency(IF), and RF parts were evaluated to be 0.24 dB, 0.05 dB, and 0.20 dB, respectively. The noise figure of the measurement system evaluated is 5 dB to 17 dB in W-band. The measurement system can be used to measure thermal noise characteristics of electronic and electrical devices, equipments, and systems as well as to calibrate noise sources.

A Study on the Implementation of the 2-Dimension Magnetic Fluxgate Sensor (2차원 Magnetic Fluxgate센서의 구현에 관한 연구)

  • Park, Yong-Woo;Kim, Nam-Ho;Ryu, Ji-Goo
    • Journal of Sensor Science and Technology
    • /
    • v.11 no.2
    • /
    • pp.67-76
    • /
    • 2002
  • We have presented a 2-dimensional fluxgate sensor with ferrite core, excitation, and pick-up coil. This fluxgate sensor system consists of a sensing element, driving circuits for excitation coil and signal processing for detecting second harmonic frequency component which is proportional to the DC magnetic to be measured. The sensor core is excited by a square waveform of voltage through the excitation coil of 80 turns. The second harmonic output of pick-up coil(x and y axis: 100 turns) is measured by FFT spectrum analyzer. This result is compared with output of PSD(phase sensitive detector) unit for detecting the second harmonic component. The measured maximum sensitivity is about 1580 V/T at driving frequency of 1.5 kHz and excitation current of 2 App. The nonlinearity of this system is measured about 2.3%(PSD) and about 1%(second harmonics of the pick-up). The angle error of the system is ${\pm}2$ %/FS.

Design of Real-Time Dead Pixel Detection and Compensation System for Image Quality Enhancement in Mobile Camera (모바일 카메라 화질 개선을 위한 실시간 불량 화소 검출 및 보정 시스템의 설계)

  • Song, Jin-Gun;Ha, Joo-Young;Park, Jung-Hwan;Choi, Won-Tae;Kang, Bong-Soon
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.8 no.4
    • /
    • pp.237-243
    • /
    • 2007
  • In this paper, we propose the Real-time Dead-Pixel Detection and Compensation System for mobile camera and its hardware architecture. The CMOS image sensors as image input devices are becoming popular due to the demand for miniaturized, low-power and cost-effective imaging systems. However a conventional Dead-Pixel Detection Algorithm is disable to detect neighboring dead pixels and it degrades image quality by wrong detection and compensation. To detect dead pixels the proposed system is classifying dead pixels into Hot pixel and Cold pixel. Also, the proposed algorithm is processing line-detector and $5{\times}5$ window-detector consecutively. The line-detector and window-detector can search dead pixels by using one-dimensional(only horizontal) method in low frequency area and two-dimensional(vertical and diagonal) method in high frequency area, respectively. The experimental result shows that it can detect 99% of dead pixels. It was designed in Verilog hardware description language and total gate count is 23K using TSMC 0.25um ASIC library.

  • PDF

Microwave Absorbing Properties of M-type Barium Ferrites with BaTi0.5Co0.5Fe11O19 Composition in Ka-band Frequencies (BaTi0.5Co0.5Fe11O19 조성을 갖는 M형 바륨 페라이트의 Ka-밴드 전파흡수특성)

  • Kim, Yong-Jin;Kim, Sung-Soo
    • Journal of the Korean Magnetics Society
    • /
    • v.19 no.6
    • /
    • pp.203-208
    • /
    • 2009
  • Magnetic and Ka-band absorbing properties have been investigated in Ti-Co substituted M-type barium hexaferrites with $BaTi_{0.5}Co_{0.5}Fe_{11}O_{19}$ composition. The ferrite powders were prepared by conventional ceramic processing technique and used as absorbent fillers in ferrite-rubber composites. The magnetic properties were measured by vibrating sample magnetometer. The complex permeability and dielectric constant were measured by using the WR-28 rectangular waveguide and network analyzer in the frequency range 26.5~40 GHz. For the Ti-Co substituted M-hexaferrites, the ferromagnetic resonance is observed at Ka-band (29.4 GHz). The matching frequency and matching thickness are determined by using the solution map of impedance matching. A wide band microwave absorbance is predicted with controlled ferrite volume fraction and absorber thickness.

Bone Mineral Density and Affecting Factors in College Women

  • Na, Hye-Bok;Jung, Shin-Yong
    • Journal of Community Nutrition
    • /
    • v.1 no.2
    • /
    • pp.98-107
    • /
    • 1999
  • The purpose of this study was to investigate Bone Mineral Density(BMD) and affecting factors on BMD of college women in Seoul. The subjects were 47 healthy college women aged 18-25 years. Antrophometric and body fat measurements were performed by Bioelectrical Impedance Fatness Analyzer(Tanita TVF 202). Blood pressure and pulse frequency were measured. Dietary intakes and general living habits were examined through questionnaires and nutrient intakes were analyzed by Computer Aided Nutritional Analysis(CAN) program for professional. Serum total cholesterol, TG(triglyceride), HDL-cholesterol, total protein, albumin, GOT, calcium were measured by Spotchem(SP-4410). Serum osteocalcin and alkaline phosphatase(ALP) were measured to monitor bone formation. BMD of lumbar spine(L2-L4), right hip(neck, ward's triangle, trochanter) and right forearm were measured by Dual Energy X-ray Absorptiometry(DEXA). Muscle strength was measured by examining leg flexion strength(right and left), leg extension power(right and left), handgrip power(right and left) and back strength. All data were statistically analyzed by the SAS PC package program. BMD of college women was normal(by WHO, 1994). Their muscle strength was bad(by national fitness guidebook, 1995). Only a mall number of them exercised (32.6% of subjects). There was no significant difference among BMD, muscle strength and % body fat(p<0.05). There were significant differences between BMD and total cholesterol as well as TG and VLDL-cholesterol(p<0.05). Total cholesterol was associated with decreasing BMD of the right forearm(p<0.05). TG and VLDL-cholesterol are associated with increasing BMD of right hip ward's triangle(p<0.05). There were significant differences among BMD, ALP and serum total protein. ALP was associated with decreasing BMD of the right forearm(p<0.05). There were significant differences between BMD and Ca as well as between Na and K intakes (p<0.05). Intakes of Na and K were associated with decreasing BMD of the right forearm (UD)(p<0.05). There were significant differences between in BMD and pulse frequently and serum albumin (p<0.05). Serum albumin is associated with increasing BMD of L3-L4(p<0.05), right hip neck(p<0.05). %Body fat, TG, VLDL-C, Ca intake, pulse frequency and serum albumin were associated with increasing BMD(p<0.05). Intakes of Na and K, ALP, total cholesterol, total cholesterol, total protein and height are associated with decreasing BMD(p<0.05). Overall results indicate that Ca intake but to be moderate in protein and Na intakes in order to increase BMD. Body exercise was recommended to increase BMD as well.

  • PDF