• Journal of the Korean Society for Precision Engineering
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• v.11 no.1
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• pp.63-70
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• 1994

This paper presents manufacturing and evaluation of a non-contact rotational torque measurement system which consists of torque cell, telemeter system, transmitter and receiver coil, transmitter, receiver and telemeter indicator. Static calibration test results show that the system has a maximum uncertaintry of 05% or less. A standar calibration system for rotational torque is used to evaluate the measurement system, As a result, the maximum uncertainty for measuring rotational torque by this system is 2% or less. We may conclude that the measurement system is sufficient to measure rotational torque of shaft in industry.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.7
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• pp.1039-1048
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• 2007

Two experiments were conducted to determine whether leptin is a metabolic signal for gonadotropin secretion in ewes. In the first experiment, twenty-eight cyclic Chal ewes were assigned randomly to an energy restricted, no leptin group (ERNL) (60% of maintenance; n = 14) and an energy normal, no leptin group (ENNL) (100% of maintenance; n = 14) for 71 days (6 estrous cycles). Estrus was synchronized with seven consecutive injections of $PGF_{2{\alpha}}$ Biweekly, body weight (BW) and body condition score (BCS) were determined and blood samples were collected to measure plasma leptin concentration. Blood samples were also taken to determine plasma progesterone concentration twice weekly. After each PG injection from the second injection to the end of experiment, four ewes were selected and blood samples were collected at 20 minutes and at hourly intervals for 3 h to detect plasma LH and FSH concentration. In the second experiment, after the ceasing of the estrous cycle caused by energy restriction, six acyclic ewes were selected and randomly allotted to two groups (n = 3) and received the following treatment for four days. Ewes in an energy restricted, leptin group (ERL) were fed with a ration which provided 60% of maintenance energy requirements and intravenously injected with $4{\mu}g$ leptin/kg BW daily. Ewes in an energy excess, no leptin group (EENL) were fed with a ration that provided 180% (120%+60%) of maintenance energy requirements and intravenously injected with 1 ml saline daily. In both groups, blood samples were collected at 20 minutes and at hourly intervals for 3 h before feeding on d 0 and d 5, and for 3 h before and after injections as above on d 2 and d 4 to detect plasma LH and FSH concentration. In the first experiment, BW and BCS from the $2^{nd}$ estrous cycle, and leptin from the $3^{rd}$ estrous cycle to the end of the experiment significantly (p<0.05) decreased. In ERNL ewes, mean plasma concentrations of FSH significantly (p<0.01) decreased from the $4^{th}$ estrous cycle to d 71 and LH pulsatile secretion was suppressed on d 71, so that, mean plasma concentrations of LH (p<0.05), LH pulse frequency (p<0.01) and LH pulse amplitude (p<0.05) significantly decreased. In the second experiment, injection of leptin significantly increased mean circulating concentrations of LH (p<0.05), LH pulse frequency (p<0.01), LH pulse amplitude (p<0.05) and mean circulating concentrations of FSH (p<0.01) and leptin (p<0.01). High energy intake significantly (p<0.05) stimulated pulsatile secretion of LH and leptin secretion (p<0.01), but non-significantly increased plasma FSH concentration. The results of this study indicate that leptin is a metabolic signal for the GnRH-LH/FSH axis in feed-restricted fat-tailed ewes.

• Journal of Animal Environmental Science
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• v.13 no.2
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• pp.113-120
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• 2007

This study was conducted to measure Nitrogen(N), Phosphate($P_2O_5$), Potassium ($K_2O$), Organic matter(OM) and Moisture content of liquid pig manure by Near Infrared Spectroscopy(NIRS) and to develop an alternative and analytical instrument which are used for measurement of N, $P_2O_5$, $K_2O$, OM, and Moisture contents for liquid pig manure. The liquid pig manure sample's transmittance spectra were measured with a NIRS in the wavelength range of 400 to 2,500 nm. Multiple linear regression and partial least square regression were used for calibrations. The correlation coefficient(RSQ) and standard error of calibration(SEC) obtained for nitrogen were 0.9190 and 2.1649, respectively. The RSQ for phosphate, potassium, organic matter and moisture contents were 0.9749, 0.5046, 0.9883 and 0.9777, and the SEC were 0.5019, 1.9252, 0.1180 and 0.0789, respectively. These results are indications of the rapid determination of components of liquid pig manure through the NIR analysis. The simple analytical instrument for liquid pig manure consisted of a tungsten halogen lamp for light source, a sample holder, a quartz cell, a SM 301 spectrometer for spectrum analyzer, a power supply, an electronics, a computer and a software. Results showed that the simple analytical instrument that was developed can approximately predict the phosphate, organic matter and moisture content of the liquid pig manure when compared to the analysis taken by NIRS. The low predictability value of potassium however, needs further investigation. Generally, the experiment proved that the simple analytical instrument was reliable, feasible and practical for analyzing liquid pig manure.

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.19-26
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• 2003

An oscillating digger mechanism was designed, constructed. and tested. The mechanism is consisted of a six-bar linkage, one four-bar linkage was fer the digger blade and the other one fur variable soil-crop separation. Experimental variables were amplitude(3, 6, 9 mm). frequency(11.2, 14.9. 17.0 Hz), and forward speed of tractor(0.91, 1.13, 1.56 km/h). Each combination of these variables was replicated three times to measure the draft and torque for power requirement evaluation. and the broken-up soil height on the soil separation sieve mechanism. Four parameters λ(the ratio of vibration speed to forward velocity), p(the ratio of vibration acceleration to forward velocity), K(the ratio of vibration acceleration to gravitational acceleration), and T(the product of λ and K) were induced from three experimental variables: amplitude, frequency, and tractor speed. And the power requirement and soil separation ability were analyzed by regression. Though λ and K were known to be the representative parameters. T was the most moderate one to explain draft. torque. and soil separation in this study. It was estimated that the T equal to or greater than 2.4 was the minimum recommended value. Figure 18 would be useful fir the selection of amplitude. frequency, or operating tractor speed once any two variables are known.

• IEMEK Journal of Embedded Systems and Applications
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• v.14 no.1
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• pp.1-9
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• 2019

In this paper, we propose a method of generating a 2D gray image from LiDAR 3D reflection intensity. The proposed method uses the Fully Convolutional Network (FCN) to generate the gray image from 2D reflection intensity which is projected from LiDAR 3D intensity. Both encoder and decoder of FCN are configured with several convolution blocks in the symmetric fashion. Each convolution block consists of a convolution layer with $3{\times}3$ filter, batch normalization layer and activation function. The performance of the proposed method architecture is empirically evaluated by varying depths of convolution blocks. The well-known KITTI data set for various scenarios is used for training and performance evaluation. The simulation results show that the proposed method produces the improvements of 8.56 dB in peak signal-to-noise ratio and 0.33 in structural similarity index measure compared with conventional interpolation methods such as inverse distance weighted and nearest neighbor. The proposed method can be possibly used as an assistance tool in the night-time driving system for autonomous vehicles.

• Journal of International Academy of Physical Therapy Research
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• v.2 no.2
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• pp.324-328
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• 2011

The purpose of this study is to measure the effect of change in heel height on lower extremities activity of young women on high-heeled shoes that young women prefer from more kinetic and realistic perspective as this study changes the degree of slope on a treadmill. The study subjects are 15 young and healthy women who do not have any external injuries or problem with walking and understand the purpose of this study clearly. They wore three different height of heels(1cm, 7cm, 12cm) and walked on a treadmill at a constant speed of 3km/h. EMG value of four muscles (anterior tibial muscle, gastrocnemius muscle, straight muscle of thigh, and biceps muscle of thigh) were collected when walking and the change according to the height of heels were analyzed using one-way ANOVA. Multiple comparison analysis on anterior tibial muscle and heel height showed that the group with 12cm heel showed significantly high muscle activation compared to the groups with 1cm and 7cm heels. The result of this study can be used for various perspectives from inferring and mediating problems caused by wearing high heels on different ground slopes for a long time.

• Journal of Sensor Science and Technology
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• v.21 no.2
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• pp.103-108
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• 2012

Radiofrequency(RF) signal is a key medium to the most of the present wireless communication devices including RF identification devices(RFID) and smart sensors. However, the most critical barrier to overcome in RFID application is in the failure rate in detection. The most notable improvement in the detection was from the introduction of EPC Class1 Gen2 protocol, but the fundamental problems in the physical properties of the RF signal drew less attention. In this work, we focused on the physical properties of the RF signal in order to understand the failure rate by noting the existence of the ground planes and noise sources in the real environment. By using the mathematical computation software, Maple, we simulated the distribution of the electromagnetic field from a dipole antenna when ground planes exist. Calculations showed that the dark area can be formed by interference. We also constructed a test system to measure the failure rate in the detection of a RFID transponder. The test system was composed of a fixed RFID reader and an EPC Class1 Gen2 transponder which was attached to a scanner to sweep in the x-y plane. Labview software was used to control the x-y scanner and to acquire data. Tests in the laboratory environment showed that the dark area can be as much as 43 %. One who wants to use RFID and smart sensors should carefully consider the extent of the dark area.

• Journal of Power System Engineering
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• v.10 no.4
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• pp.5-10
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• 2006

The purpose of this study is to measure the droplet distribution and Sauter mean diameter(SMD) of biodiesel fuel, using the immersion sampling method. This method involves using an optical microscope and a CCD camera, to take an image of the droplets. These images are then measured by using a 'Sigma Scan' processing program. The results of the above experiment are summarized as followed ; (1) There can be as much as a 10% error rate when measuring the diameter of these droplets, using the image processing method and the naked eye. (2) The result of droplet size distribution test, TVO(transesterified vegetable oil) big size droplet distribution were increased at ambient pressure $6kg/cm^2$. (3) When ambient pressure increased $6kg/cm^2$ above, SMD variation of TVO and UVO(used vegetable oil) 30 are small. (4) On Rosin-Rammler analysis, droplets size distribution of UVO(used vegetable oil) 30 uniform more than TVO 20 on ambient pressure $1kg/cm^2$.

• Journal of the Korean Magnetics Society
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• v.12 no.6
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• pp.206-211
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• 2002

We have constructed a new kind of magnetic motion capture sensor based on the pulse magnetic field method. 3-orthogonal magnetic pulse fields were generated in turns only one period of sinusoidal waveform using 3-orthogonal magnetic dipole coils, ring counter and analog multiplier. These pulse magnetic fields were measured with 3-orthogonal search coils, of which induced voltages by the x-, y-, and l-dipole sources using S/H amplifier at the time position of maximum induced voltage. Using the developed motion capture sensor, we can measure position of sensor with uncertainty of ${\pm}$0.5％ in the measuring range from ${\pm}$0.5 m to ${\pm}$1.5 m.

• Journal of The Korean Astronomical Society
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• v.48 no.4
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• pp.213-228
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• 2015

The Horizon Run 4 is a cosmological N-body simulation designed for the study of coupled evolution between galaxies and large-scale structures of the Universe, and for the test of galaxy formation models. Using 6300³ gravitating particles in a cubic box of L_box = 3150 h⁻¹Mpc, we build a dense forest of halo merger trees to trace the halo merger history with a halo mass resolution scale down to M_s = 2.7 × 10¹¹h⁻¹M_⊙. We build a set of particle and halo data, which can serve as testbeds for comparison of cosmological models and gravitational theories with observations. We find that the FoF halo mass function shows a substantial deviation from the universal form with tangible redshift evolution of amplitude and shape. At higher redshifts, the amplitude of the mass function is lower, and the functional form is shifted toward larger values of ln(1/σ). We also find that the baryonic acoustic oscillation feature in the two-point correlation function of mock galaxies becomes broader with a peak position moving to smaller scales and the peak amplitude decreasing for increasing directional cosine μ compared to the linear predictions. From the halo merger trees built from halo data at 75 redshifts, we measure the half-mass epoch of halos and find that less massive halos tend to reach half of their current mass at higher redshifts. Simulation outputs including snapshot data, past lightcone space data, and halo merger data are available at http://sdss.kias.re.kr/astro/Horizon-Run4.