• Journal of the Institute of Convergence Signal Processing
• /
• v.12 no.4
• /
• pp.291-297
• /
• 2011

In this paper, the differential quantized method and the parallel method to reduce the size of ROM in the direct digital frequency synthesizer(DDFS) is proposed And we design the DDFS by FPGA The new ROM compression method can reduce the ROM size by using the two ROM. The quantized value of sine is saved by the quantized-ROM(Q-ROM) and the differential ROM(D-ROM). Also we design the phase-to-sine converter using the phase accumulator of parallel type for generating the high frequency. So the total size of the ROM in the proposed DDFS is significantly reduced compared to the original ROM The ROM compression ratio of 67.5% is achieved by this method. Also, the power consumption is decreased according to the ROM size reduction and we can design the DDFS generating the high frequency.

• Journal of Korean Society of Forest Science
• /
• v.21 no.1
• /
• pp.39-45
• /
• 1974

The objects of this study are to induce the experimental equation suitable to estimate the height growing process, and to get some information that could be to reduce the error percent on determining the site index. The height growing process per sample plot were made up from the height age curve getted through the stem-analysis of the dominant tree. The 11 equations were calculated in the functional formulas between the age and the dominant height of Alnus hirsuta, Larix leptolepsis, L. Gmelini, P. koraiensis, Abies holophylla, P. rigida, Q. acutissima and Q. aliena. The suitable equation for estimating the guide curve were selected with the highest correlation and the low standard error with comparision on the age-height distributed map as Fig. 2. The suitable equation is different between the species as their calculated results as follows; The growing process of tree height are occasionally found to be polymorphous in the growth pattern as Fig. 3. By this result, the site index are practically found to be always not constant but shows variation to age in same plot as example 5. So, that the site index are estimated from the height-growth curve to age drawing by the stem-analysis or the polymorphic-curve, are concluded to be suitable on the study of site evaluation.

• The Korean Journal of Physiology
• /
• v.16 no.2
• /
• pp.129-136
• /
• 1982

We studied this experiment to compare the effects of exercise and other body conditions: i.e., Flack test, cold pressor test and bicycle ergometry on the electrocardiogram. We had sixty healthy college students who were thirty nine men and twenty one women. Their $mean{\pm}SD$ values of physical characteristics were as follows: age; $22.0{\pm}1.4$, weight; men $61.7{\pm}5.6\;kg$, women $46.2{\pm}7.47\;kg$. We observed the changes of P-Q and Q-T interval, R and T amplitude, mean QRS vector, S-T segment deviation, and P and T vector. The result obtained were summarized as follows: P vector was shifted rightward regardless of the type of stress. T vector was shifted var-in each stress but in the bicycle ergometry T vector was shifted leftward. Mean QRS vector was shifted rightward immediately after the bicycle ergometry. Percentage of the occurrence of the depression of S-T segment was 21.7% at the immediately after the submaximal bicycle ergometry in lead II. The elevation of S-T segment was often observed after the mild stresses. Increased amplitude of T wave in the cold pressor test and decreased amplitude of T wave in the bicycle ergometry were observed. In the bicycle ergometry and other stresses, the precise mechanism of S-T segment changes was unexplained but insufficient repolarization in base or apex of the left ventricle due to heart strain was indicated by so called S-T vector analysis.

• Korean Journal of Clinical Laboratory Science
• /
• v.40 no.1
• /
• pp.41-47
• /
• 2008

Colorectal carcinoma is occurred frequently to Korean and so ranked the fourth from various cancers. Due to western dietary life, this cancer has been increased continually. Therefore, the study will be needed to find a candidate gene involved in the development and progression of colorectal carcinoma and to diagnose and treatment helpfully. The striking feature from cancer suppressor genes is known for LOH (loss of heterozygosity), which is the method to find allele genetic loss or mutation of cancer cell. The purpose of this study was designed to find a carcinogenic gene from colon cancer using microsatellite marker on 17th and 18th chromosome from 30 subjects. The LOH was investigated in order of D18S59 57% (17/30), TP53CA 50% (15/30), D18S68 47% (14/30), D18S69 43% (13/30). The genetic mutation depends on loci of colorectal carcinoma was shown higher with 2.44 from colon cancer than with 1.25 from right colorectal carcinoma (p<0.032). The genetic mutation with lymph nodes was investigated higher with 2.69 at mutated group than with 1.14 at non-mutated group (p<0.003). At genetic mutated pattern depends on disease stage, there was higher significant difference at III-IV stage 2.50 than that of I-II stage 1.17, respectively (p=0.015). There was no difference at comparison between histological classification and serological CEA increase. The loss on 18q21 found in this study is highly recurrence loci and was observed 43% for Korean with high recurrence. Therefore, LOH is a very useful tool to detect 18q21 loci in clinical application, prior to the treatment of colorectal carcinoma. After the operation of colorectol carcinoma, the efficient application using LOH at operated part tissue which is designed to protect the recurrence as well as its cure will be needed.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.9 no.2
• /
• pp.1301-1305
• /
• 1967

Ground water flow can be studied with model test. Model test of ground water works are necessary for economic and safe design of the works. Also influence of the ground water flow to the durability and safety of hydraulic structures can be studied with this model. a. Sand model ; Water flow through porous media is the principle of sand model. Darcy's formula is the basic equation, $q=k{\frac{dh}{ds}}^{\circ}. The effect of the ground water flow on the grain system itself is represented with this model only. b. Hele-Shaw model ; In this model use is made of the viscous flow analogy. Viscous fluid such as glycerine flowing through two parallel plates depends on Poiseuille law, $q=-c{\frac{dh}{ds}}$. The analogue can be used vertically and horizontally. c. Heat model ; This is based on the analogy of the Fourier's law for heat conduction and Darcy's law for ground water flow. Especially unsteady problem can be studied with this model. A difficulty of the construction of this model is the isolation, which has to prevent losses of the heat. d. Electirc model ; Ohm's law for electric current is analogous to Darcy's law. Resistance material such as metal foil, graphite block, water with salt added, gelatine with salt added, ete. is connected to electric sources and resistor, and equi-voltage line is detected with galvanometer, $N_aCl$, $CuSo_4$, etc. are used as salt in the model. e. Membrane model ; This model is based on the facts that the deflection of a thin membrane obeys Laplace's equation if there is no load in the direction perpendicular to the membrane, and if the dellection is small.

• Journal of Elementary Mathematics Education in Korea
• /
• v.15 no.1
• /
• pp.77-93
• /
• 2011

Jisuguimundo(地數龜文圖) is a magic hexagon created by Suk-Jung Choi in his book about three hundreds years ago in Korea. Recently attention is focused on jisuguimundo, and it is known that jisuguimundos exist when magic number is from 77 to 108, however a general method making jisuguimundos is not known so far. Up to now, methods of making jisuguimundos using computers are known. In this study, a method making jisuguimundos is suggested using pairs of two numbers with sum p and q ($p{\neq}q$) alternately when magic number is from 88 to 92, and from 94 to 98, without using computer in elementary math class as a task for problem solving. Mathematical theory is introduced for this method, and jisuguimundos are presented which are found out through this method. Elementary students are expected to make their own jisuguimundo using this method.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.24 no.10A
• /
• pp.1563-1570
• /
• 1999

This paper relates to the soft decision method with erasure technique in digital terrestrial television broadcasting system. The proposed decoder use the CSI derived from using the pilots in receiver. The active real(I) and imaginary(Q) data are transferred to the branch metric calculation block that decides the Euclidean distance for the soft decision decoding and also the estimated CSI values are transferred to the same block. After calculating the Euclidean distance for the soft decision decoding, the Euclidean distance of branch metric is multiplied by CSI. To do so, new branch metric values that consider each carrier state information are obtained. We simulated this method in better performance of about 0.15dB to 0.17dB and 2.2dB to 2.9dB in Rayleigh channel than that of the conventional soft decision Viterbi decoding with or without bit interleaver where the constellation is QPSK, 16-QAM and 64-QAM.

• Mycobiology
• /
• v.42 no.4
• /
• pp.346-352
• /
• 2014

Recently, the Q biotype of tobacco whitefly has been recognized as the most hazardous strain of Bemisia tabaci worldwide, because of its increased resistance to some insecticide groups. As an alternative control agent, we selected an Isaria javanica isolate as a candidate for the development of a mycopesticide against the Q biotype of sweet potato whitefly. To select optimal mass production media for solid-state fermentation, we compared the production yield and virulence of conidia between 2 substrates (barley and brown rice), and we also compared the effects of various additives on conidia production and virulence. Barley was a better substrate for conidia production, producing $3.43{\times}10^{10}$ conidia/g, compared with $3.05{\times}10^{10}$ conidia/g for brown rice. The addition of 2% $CaCO_3+2%$ $CaSO_4$ to barley significantly increased conidia production. Addition of yeast extract, casein, or gluten also improved conidia production on barley. Gluten addition (3% and 1.32%) to brown rice improved conidia production by 14 and 6 times, respectively, relative to brown rice without additives. Conidia cultivated on barley produced a mortality rate of 62% in the sweet potato whitefly after 4-day treatment, compared with 53% for conidia cultivated on brown rice. The amendment of solid substrate cultivation with additives changed the virulence of the conidia produced; the median lethal time ($LT_{50}$) was shorter for conidia produced on barley and brown rice with added yeast extract (1.32% and 3%, respectively), $KNO_3$ (0.6% and 1%), or gluten (1.32% and 3%) compared with conidia produced on substrates without additives.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.45 no.1
• /
• pp.56-63
• /
• 2008

This paper describes a 12 bit 1GS/s current mode segmented DAC for WCDMA communication. The proposed circuit in this paper employes segmented structure which consists of 4bit binary weighted structure in the LSB and 4bit thermometer decoder structure in the mSB and MSB. The proposed DAC uses delay time compensation circuits in order to suppress performance decline by delay time in segmented structure. The delay time compensation circuit comprises of phase frequency detector, charge pump, and control circuits, so that suppress delay time by binary weighted structure and thermometer decoder structure. The proposed DAC uses CMOS $0.18{\mu}m$ 1-poly 6-metal n-well process, and measured INL/DNL are below ${\pm}0.93LSB/{\pm}0.62LSB$. SFDR is approximately 60dB and SNDR is 51dB at 1MHz input frequency. Single DAC's power consumption is 46.2mW.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.6
• /
• pp.1469-1473
• /
• 2010

Influences of alrylamino (R) substituents on the herbicidal activity ($pI_{50}$) of 1-(4-chloro-2-fluoro-5-propargyloxypheny)-3-(R)-thiourea analogues (1 ~ 35) against the barnyard grass (Echinochloa crusgalli) in the pre-emergence step were discussed quantitatively using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) as the three dimensional quantitative structure-activity relationship (3D-QSAR) method. The statistically most satisfactory CoMFA models for the herbicidal activity against the barnyard grass had the better predictability ($r^2{_{cv.}}$) and correlativity ($r^2{_{ncv.}}$) than those of CoMSIA models. The optimized CoMFA model 1($r^2{_{cv.}}$ = 0.531 & $r^2{_{ncv.}}$ = 0.931) with the sensitivity to the perturbation (${d_q}^{2'}{dr^2}_{yy'}$ = 1.081) and the prediction ($q^2$ = 0.475) produced by a progressive scrambling analyses were not dependent on chance correlation. And statistical qualities with the atom based fit alignment (AF) were slightly higher than those of the field fit alignment (FF). According to the optimized CoMFA model 1, the contribution ratio (%) of the steric field (76.9%) on the herbicidal activity of the Thioureas was three-fold higher than that of the electrostatic field (20.1%) and the hydrophobic field (3.0%) had the least influence. A steric favor group is on the vicinity of the nitrogen atom in alrylamino (R) substituent, and a steric disfavor group is on the outer side of alrylamino (R) substituent. Thus, as the size of alrylamino (R) substituent increases, so does the herbicidal activity of the substituent.