• Title/Summary/Keyword: slow light

Search Result 205, Processing Time 0.028 seconds

Single Gyroscope Sensor Module System for Gait Event Detection (보행시점 검출을 위한 단일 각속도 센서모듈 시스템)

  • Kang, Dong-Won;Choi, Jin-Seung;Kim, Han-Su;Oh, Ho-Sang;Seo, Jeong-Woo;Tack, Gye-Rae
    • Korean Journal of Applied Biomechanics
    • /
    • v.21 no.4
    • /
    • pp.495-501
    • /
    • 2011
  • The purpose of this study was to develop the inertial sensor module system to detect gait event using single angular rate sensor(gyroscope), and evaluate the accuracy of this system. This sensor module is attached at the heel and gait events such as heel strike, foot flat, heel off, toe off are detected by using proposed automatic event detection algorithm. The developed algorithm detect characteristics of pitch data of the gyroscope to find gait event. To evaluate the accuracy of system, 3D motion capture system was used and synchronized with sensor module system for comparison of gait event timings. In experiment, 6 subjects performed 5 trials level walking with 3 different conditions such as slow, preferred and fast. Results showed that gait event timings by sensor module system are similar to that by kinematic data, because maximum absolute errors were under 37.4msec regardless of gait velocity. Therefore, this system can be used to detect gait events. Although this system has advantages of small, light weight, long-term monitoring and high accuracy, it is necessary to improve the system to get other gait information such as gait velocity, stride length, step width and joint angles.

Non-isothermal Crystallization Behaviors of Ethylene-Tetrafluoroethylene Copolymer (에틸렌-테트라플르오르에틸렌 공중합체의 비등온 결정화 거동)

  • Lee, Jaehun;Kim, Hyokap;Kan, Ho-Jong
    • Polymer(Korea)
    • /
    • v.36 no.6
    • /
    • pp.803-809
    • /
    • 2012
  • The non-isothermal crystallization behavior of ethylene-tetrafluoroethylene (ETFE) copolymer was investigated by DSC and imaging FTIR analysis. Modified non-isothermal Avrami analysis was applied to interpret the crystallization behavior of ETFE. It was found that the less linearity in ln[-ln(1-X(t))] vs. ln(t) plot was obtained in thermal analysis comparison with imaging FTIR due to relatively small crystallization enthalpy change in ETFE. It means that imaging FTIR measured by overall IR absorption intensity change due to the crystallization was found to be effective to understand the non-isothermal crystallization kinetics of ETFE. In addition, the optical transmittance of ETFE was studied. The crystallite developed by slow cooling caused the light scattering and resulted in the increase of haze and the lowering of transmittance up to 8%. From our results, it was confirmed that cooling rate is an important processing parameter for maintaining optical transmittance of ETFE as a replacement material for glass.

Estimation of Visual Stimulus Intensity From Retinal Ganglion Cell Spike Trains Using Optimal Linear Filter (최적선형필터를 이용한 망막신경절세포 Spike Train으로부터의 시각자극 세기 변화 추정)

  • Ryu, Sang-Baek;Kim, Doo-Hee;Ye, Jang-Hee;Kim, Kyung-Hwan;Goo, Yong-Sook
    • Journal of Biomedical Engineering Research
    • /
    • v.28 no.2
    • /
    • pp.212-217
    • /
    • 2007
  • As a preliminary study for the development of electrical stimulation strategy of artificial retina, we set up a method fur the reconstruction of input intensity variation from retinal ganglion cell(RGC) responses. In order to estimate light intensity variation, we used an optimal linear filter trained from given stimulus intensity variation and multiple single unit spike trains from RGCs. By applying ON/OFF stimulation(ON duration: 2 sec, OFF duration: 5 sec) repetitively, we identified three functional types of ganglion cells according to when they respond to the ON/OFF stimulus actively: ON cell, OFF cell, and ON-OFF cell. Experiments were also performed using a Gaussian random stimulus and a binary random stimulus. The input intensity was updated once every 90 msec(i. e. 11 Hz) to present the stimulus. The result of reconstructing 11 Hz Gaussian and binary random stimulus was not satisfactory and showed low correlation between the original and reconstructed stimulus. In the case of ON/OFF stimulus in which temporal variation is slow, successful reconstruction was achieved and the correlation coefficient was as high as 0.8.

VARIABLE STARS IN THE REGION OF CYG OB3 ASSOCIATION CENTERED ON THE OPEN CLUSTER NGC 6871 II (산개성단 NGC 6871을 중심으로 한 Cyg OB3 성협 영역의 변광성 II)

  • Jeon, Young-Beom;Park, Yoon-Ho;Lee, UiRyeol;Kim, DongHyeon;Jang, Hyeeun;Cho, SungYoon
    • Publications of The Korean Astronomical Society
    • /
    • v.28 no.3
    • /
    • pp.83-93
    • /
    • 2013
  • This is the second paper on a systematic search for variable stars in Cyg OB3 region. In this paper we present the observational properties of 46 variable stars found in the region. Among them, 27 are eclipsing binaries and others are semi-long periodic or slow irregular variables. Only 5 are known variables and the rest are newly discovered ones. We have obtained the period and amplitude of 20 eclipsing binaries using the phase fitting method, and present the light curves of 46 variable stars.

The Effect of Sodium Sulfate in Liquid or Solid Form on Reactive Dyeing and Fastness Properties of Cellulose Knitted Fabric (액상 또는 분말망초 Type에 따른 Cellulose 편성물의 반응성염료에 대한 염색성과 견뢰도 연구)

  • Kim, Mi-Ri;Lee, Hae-Jung;Lee, Jung-Jin
    • Textile Coloration and Finishing
    • /
    • v.22 no.4
    • /
    • pp.341-348
    • /
    • 2010
  • Sodium sulfate is commonly added in reactive dyebath in order to increase substantivity of the reactive dye to cellulose fiber by reducing repulsion between anionic dye and fiber. While sodium sulfate is mostly used in solid form, it is inconvenient to dissolve a large amount of powder sodium sulfate. Furthermore, if there is undissolved salt in dyebath it might cause unlevel dyeing. In this study, sodium sulfate in liquid or solid form was used in dyeing of cellulose fabric with reactive dyes of three primary color and the effect of type or amount of sodium sulfate on dyeing and fastness properties was investigated. When the amount of sodium sulfate rose to 30-50 g/l, K/S value of the dyed fabric markedly increased; further rise in sodium sulfate concentration resulted in slow increase in K/S value. For light color, optimum amount was about 30 g/l in solid form and 50-100 g/l in liquid form while, for medium to deep color, it was 50 g/l and 100-150 g/l in solid and liquid form, respectively. When using each optimum amount of salt in solid or liquid form for medium color, shape of dyeing curve as well as exhaustion was similar to each other. On the whole, similar color fastness results were obtained regardless of type or amount of sodium sulfate.

Cell Biological Studies of the Effect of Aromatic Amino Acids on Early Development of Chick Embryo (방향족 아미노산이 초기계배에 미치는 영향에 관한 세포생물학적 연구)

  • 최임순;주충노;최춘근;김재원
    • The Korean Journal of Zoology
    • /
    • v.28 no.4
    • /
    • pp.257-278
    • /
    • 1985
  • The effect of aromatic amino acids such as phenylalaine, tryptophan and tyrosine on somitogenesis at the early stage of chick embryo has been investigated morphologically using light and electron microscopy. Micrographs of aromatic amino acid injected chick embryo showed that an incomplete somite segmentation occurred and some decremental effect on the nervous system were observed. Somites were poorly developed and their size were variable. Electron micrograph of somatic cells from aromatic amino acid injected chick embryo showed that chromatins were coagulated, some of mitochondria were damaged, and nucleus were transformed considerably in some cases. The protein and nucleic acid levels and some enzyme activities of 15-day chick embryo which received the injection of 1mg of aromatic amino acid in 0.05 ml of saline 24 hours after the incubation were analyzed. Protein, DNA and RNA levels of the test group were not lowered significantly but the activities of enzymes for basic metabolism, such as lactate dehydrogenase, succinate dehydrogenase, malate dehydrogenase and glucose 6-phosphate dehydrogenase were considerably lowered as compared with those of control. From the present expeerimental results, it was tentatively suggested that the administration of amino acid might slow down the yolk granule degradation probably by feed back mechanism resulting in the disturbance of amino acid balance in the cell, which might give rise to impair normal metabolic pattern leading to abnormal somitogenesis to chick embryo at very early stage of development.

  • PDF

Photocatalytic Oxidation of 2-Mercaptoethanol to Disulfide using Sb(V)-, P(V)-, and Ge(IV)-porphyrin Complexes

  • Shiragami, Tsutomu;Onitsuka, Dai;Matsumoto, Jin;Yasuda, Masahide
    • Rapid Communication in Photoscience
    • /
    • v.3 no.4
    • /
    • pp.70-72
    • /
    • 2014
  • Visible-light irradiation of MeCN solution containing di(hydroxo)metallo(tetraphenyl)porphyrin complex $(tppM(OH)_2$: 1a; $M=Sb(V)^+Br^-$, 1b; $M=P(V)^+Cl^-$, 1c; M=Ge(IV)) and 2-mercaptoethanol (2-ME) as a substrate under aerated condition gave bis(2-hydroxyethyl)disulfide (2-HEDS) as an oxidative product of 2-ME. It is indicated that the oxidation of 2-ME should proceed with a photocatalytic process by 1, because the turn over number (TON) for the formation of 2-HEDS was over unit. The TON was determined to be 642 as a maximum value when 1a was used as a sensitizer. The formation of 2-HDES was extremely slow under argon atmosphere. The fluorescence of 1 was not quenched by 2-ME at all, and the free energy change (${\Delta}G$) with electron transfer (ET) from 2-ME to excited triplet state of $1(^31^*)$ was estimated as a negative value. The quenching rate constant ($k_r$) of $^31^*$ by 2-ME, obtained by the kinetics for the formation of 2-HEDS, strongly depends on ${\Delta}G$. These findings indicate that 1-sensitized oxidation was initiated by photoinduced ET from 2-ME to $^31^*$ to generate both radical cation of 2-ME ($2-ME^{+\bulle}$) and porphyrin radical anion ($1^{-\bulle}$), resulting that the formation of 2-HEDS can be proceeded by the dimerization of $2-ME^{+\bulle}$, and through a catalytic cycle due to returning to 1 by the ET from $1^{-\bulle}$ to molecular oxygen.

Developmental Proteomic Profiling of Porcine Skeletal Muscle during Postnatal Development

  • Kim, Nam-Kuk;Lim, Jong-Hyun;Song, Min-Jin;Kim, Oun-Hyun;Park, Beom-Young;Kim, Myung-Jick;Hwang, In-Ho;Lee, Chang-Soo
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.20 no.10
    • /
    • pp.1612-1617
    • /
    • 2007
  • In this study, we have compared the skeletal muscle proteome at various stages of porcine postnatal development. Korean native pigs were divided into five postnatal stages of 30, 70, 130, 170 and 300 d and their loin muscles were analyzed for muscle proteome by using two-dimensional electrophoresis and mass spectrometry. We found 5 proteins showing a consistent pattern during skeletal muscle growth. Four proteins were identified as myosin light chain 1 slow-twitch (MLC1sa) isoform, troponin T, triosephosphate isomerase (TIP) and DJ-1 protein. The remaining protein was not identified. Two muscle fiber proteins of MLC1sa isoform and troponin T showed a high expression level at an early postnatal stage and then their levels were decreased markedly during growth stages. On the other hand, the expression of TIP and DJ-1 protein, which are well known as catalysis enzyme and antioxidant-related protein, respectively, were linearly increased during growth stages. Thus, the stage-related muscle proteins may be useful as parameters for understanding the developmental characteristics of biochemical and physiological properties in Korean native pig skeletal muscle.

The Effect of Culture Tourism Interpreter's Role on Visitors' Festival Theme Awareness and Satisfaction (문화해설사의 역할이 방문객의 축제주제인식과 만족에 미치는 영향)

  • Yang, Soung-Hoon
    • The Journal of the Korea Contents Association
    • /
    • v.17 no.12
    • /
    • pp.437-446
    • /
    • 2017
  • This research were aimed to verify possible transferring regional development's value into festival contents. It was widely known that Korean festival's theme has been relatively pale in comparing its abundancy, which were required variety of festival contents. Luckily, local residents in Cittaslow frequently host slow-themed festivals, not only to revitalize their communities but also to serve the visitors. Those phenomenon shed the light to study the culture tourism interpreters' role as the presenter of regional development value to visitors at festival setting. Total 180 of questionnaires were administered to Gimsatgat festival visitors, verifying the relationship of variables, interpreters' role, perception of festival theme, revisit intention and practice intention. Regression analysis revealed that significantly influential relations between variables. Successful interpreters will support visitors' understanding of Cittaslow value, satisfaction and practice in daily life. Theoretical /practical significances and research limitation were included.

Trend analysis of X Window used in Linux (리눅스에 사용되는 X 윈도 동향 분석)

  • Sung, Kyung
    • Journal of Digital Contents Society
    • /
    • v.18 no.7
    • /
    • pp.1393-1401
    • /
    • 2017
  • The Linux operating system is expanding to include desktops and servers, as well as mobile devices, automobiles and embedded devices, and is the dominant operating system category because it is freely available and open source software. However, the desktop market is dominated by Microsoft's Windows, and Apple's Mac OS is increasingly dominated by enthusiasts, but Linux's growth is stagnant. An important element to make up for this deficiency is the X Window System. Most Linux distributions still use the traditional X.org server as the X Window System, but it is heavy and slow. To replace it, a new X window system called Wayland emerged. Wayland is small and light enough to fit on an embedded or mobile device, so it can be mounted on the IoT related device as well as on the desktop. With the advent of Wayland, the change in the X window will accelerate the popularization of Linux.