• Journal of rehabilitation welfare engineering & assistive technology
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• v.11 no.2
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• pp.115-124
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• 2017

This study was to develop the balance insole system for detecting and improving the muscle imbalance of left and right side in lower limbs. We were to verify the validation of balance insole system by analyzing the strategy of muscular activities and foot pressure according to sound feedback. We developed the balance insole based FSR sensor modules for estimating the muscle imbalance using detecting foot pressure. The insole system was FPCB have 8-spot FSR sensor with sensitivity range of 64-level. The participants were twenty peoples who have muscle strength differences in left and right legs over 20%. We measured the muscular activity and foot pressure of left and right side of lower limbs in various gait environment for verifying the improvement effect of muscle imbalance according to sound feedback. They performed gait in slope at 0, 5, 10, 15% and velocity at 3, 4, 5km/h. The result showed that the level of muscle imbalance reduced within 30% for sound feedback of balance insole system contrast to high level of muscle imbalance at 169.9~246.8% during normal gait for increasing slope and velocity. This study found the validation of balance insole system with sound feedback stimulus. Also, we thought that it is necessary to research on the sensitivity of foot area, detection of muscle imbalance and processing algorithm of correction threshold spot.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.1
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• pp.7-13
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• 2015

In this study, the effective treatment reducing geosmin and dosage of PAC was suggested when taste & odor compounds flow in. The removal efficiency of geosmin was evaluated with types of chlorination. In case of low geosmin concentration below 25 ng/L, removal efficiency of geosmin was estimated at 46% by combined treatment of pre and intermediate-chlorination. But, in the exclusive intermediate-chlorination treatment, removal efficiency of geosmin was increased to 57%. In the medium geosmin concentration (25~79 ng/L), removal efficiency of geosmin was estimated at 59% by combined treatment. But, in the exclusive intermediate-chlorination treatment, removal efficiency of geosmin was increased to 87%. When high geosmin concentration above 80 ng/L flows in, removal efficiency of geosmin was estimated at 69% by combined treatment. However, in the exclusive intermediate-chlorination treatment, removal efficiency of geosmin was increased to 95%. Then, the exclusive intermediate-chlorination has an important effect on removal of geosmin. After correlation of geosmin concentration and dosage of PAC was analyzed, the coefficient of determination was estimated at 0.96. And, the proper PAC dosage chart was proposed. Also, at a initial occurrence of geosmin, when the combined treatment by intermediate-chlorination and PAC was applied, particle-bound geosmin should be removed continuously. Finally, it is proved that the combined treatment was effective to remove the geosmin by threshold levels as well as to reduce the dosage of PAC.

• Korean journal of applied entomology
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• v.39 no.1
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• pp.21-24
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• 2000

These studies were conducted to investigate the effect of temperature on the developmentof Delia platura (Meigen) under a laboratory condition at five different temperatures. The developmentalperiods of D. platurcr from egg to adult emcrgence at the temperatures of 11, 15, 19, 23, and 27$^{\circ}$C were67.8k 14.5, 43.7t-9.4, 31.2-t-7.0, 22.4k4.9, and 18.3k4.1 days, respectively. Based on these results,threshold temperature of development and effective cumulative degree-day (DD) for overall developmentwas 0.6"C and 579.8 DD, respectively. Generation of time D. pluturci averaged 30.8 days, and meannumber of eggs produced per female was 246.5 k 16.9 at 23$^{\circ}$C. Hatching rate and emergence rate curvesin relation to the temperature was dome shaped with the peak of 90.0 and 85.2% at 23"C, it wassuggesting that hatching and emergence were inhibited by high temperature above that temperature.Pupation rate of the insect reared on garlic and on onion were higher than those reared on other diets.Oviposition of D. platum usually began 7-9 days after emergence at 23$^{\circ}$C. Females laid about 3-4 eggsin a day. Oviposition of the females peaked at the age of 12- 18 days after emergence. of 12- 18 days after emergence.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.2
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• pp.67-74
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• 2008

This paper proposes two peak-windowing algorithms for peak-to-average power reduction(PAPR) of orthogonal frequency division multiple access(OFDMA) downlink systems. The Proposed algorithms mitigate the effect of excessive suppression due to successive peaks or relatively high peaks of the signal. First, multi-stage peak windowing algorithm is proposed, which exploits multiple threshold of target PAPR in order to step down the peaks gradually. Secondary, variable-length peak windowing algorithm is proposed, which adapts the window length with respect to the existence of successive peaks within a half of window length. Therefore, the proposed method reduces the distortion of signal amplitude caused by window overlapping. The proposed algorithms outperform the conventional peak windowing with the aid of window-length adaptation or sequential peak power reduction. Simulation results show the efficiency of the proposed algorithms over OFDMA downlink systems, especially WiBro systems.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.10
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• pp.1852-1859
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• 2016

The effectiveness of a binarization algorithm in image processing depends on how to eliminate the uncertainty of determining threshold in a reasonable way and on minimizing information loss due to the binarization effect. Fuzzy binarization technique was proposed to handle that uncertainty with fuzzy logic. However, that method is known to be inefficient when the given image has low intensity contrast. In this paper, we propose an improved fuzzy binarization method to overcome such known drawbacks. Our method proposes a trapezoid type fuzzy membership function instead of most-frequently used triangle type one. We also propose an adaptive ${\alpha}$_cut determination policy. Our proposed method has less information loss than other algorithms since we do not use any stretching based preprocessing for enhancing the intensity contrast. In experiment, our proposed method is verified to be more effective in binarization with less information loss for many different types of images with low intensity contrast such as night scenery, lumber scoliosis, and lipoma images.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.461-467
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• 2012

Developmental characteristics of Geocoris pallidipennis were investigated at a constant temperature ($20{\pm}1$, $25{\pm}1$, $30{\pm}1$, $35{\pm}1$, $37.5{\pm}1$ and $40{\pm}1^{\circ}C$), under long day illumination 16:8 (L:D) and constant relative humidity ($80{\pm}10%$). From egg to adulthood, the lower developmental threshold and the effective accumulative temperature were $14.8^{\circ}C$ and 399.1 day-degree, respectively. The experimental results at $35^{\circ}C$ were as follows. The egg period was 5.6 days (hatchability: 81.1%) and the nymphal period was 14.3 days (1st: 3.2, 2nd: 2.2, 3rd: 2.7, 4th: 2.7, 5th: 3.6). Female longevity was 33.8 days and the oviposition period was 29.2 days. Total egg production was 111.2 eggs and the maximum daily egg production was 14.8 eggs (in 7th days). However, although some eggs and nymphs developed at $37.5^{\circ}C$, G. pallidipennis could not develop at $40^{\circ}C$, The total egg production at $40^{\circ}C$ was only 22.1 eggs. When G. pallidipennis was fed on Bemisia tabaci pupae, daily prey consumption by nymphs (1st, 3rd and 5th) and adults was 1.9, 7.3, 18.7 and 29.5, respectively.

• Journal of dental hygiene science
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• v.14 no.3
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• pp.405-410
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• 2014

The purpose of this study in vitro investigation was to compare the marginal and internal fit of Ni-Cr alloy metal ceramic crown before and after porcelain veneering. Furthermore, this study evaluated whether the influence of the porcelain firing on the precision of fit of dental prostheses. The maxillary right incisor was selected as an abutment for experiments. Ten working models were prepared. Ni-Cr alloy cores appropriate for each abutment were prepared by lost wax technique. The marginal area and four internal areas of the crowns were measured at two stages: before veneering process and after upper porcelain firing. Silicone replica techniques were used. The data were statistically analyzed with the paired t-test (${\alpha}=0.05$). $Mean{\pm}SD$ marginal and internal gap were $67.1{\pm}23.3{\mu}m$ for the nickle chrome alloy core group and $74.4{\pm}21.9{\mu}m$ for the metal ceramic crown group. There were statistically significant differences in all investigated areas (p<0.05). Within the limitations of this study, none of the Ni-Cr alloy metal crown values measured after porcelain firing process exceeded $120{\mu}m$, which is the clinically acceptable threshold.

• Journal of Radiation Protection and Research
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• v.33 no.2
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• pp.53-59
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• 2008

We observed DNA damages as a function of mean absorbed dose to identify the indirect effect of high-energy radiation such as x-ray. Monolayer films of lyophilized pGEM-3Zf(-) plasmid DNA deposited on tantalum foils were exposed to Al $K{\alpha}$ X-ray (1.5 keV) for 0, 3, 7 and 10 min, respectively, in a condition of ultrahigh vacuum state. We compared DNA damages by X-ray irradiation with those by 3 eV electron irradiation. X-ray photons produced low-energy electrons (mainly below 20 eV) from the tantalum foils and DNA damage was induced chiefly by these electrons. For electron beam irradiation, DNA damage was directly caused by 3 eV electrons. Irradiated DNA was analyzed by agarose gel electrophoresis and quantified by ImagaQuant program. The quantities of remained supercoiled DNA after irradiation were linearly decreased as a function of mean absorbed dose. On the other hand, the yields of nicked circular (single strand break, SSB) and interduplex crosslinked form 1 DNA were linearly increased as a function of mean absorbed dose. From this study, it was confirmed that DNA damage was also induced by low energy electrons ($0{\sim}10\;eV$) even below threshold energies for the ionization of DNA.

• Journal of Pharmacopuncture
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• v.3 no.1
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• pp.35-51
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• 2000

The purpose of this study is to prove the analgesic effects of apitoxin and its mechanism via jaw-opening reflex(JOR) and measuring expression of mRNA in Phospholipase and Tryptophan hydroxylase(TPH) using RT-PCR. The experiments were carried out on Sprague-Dawley rats(300-400g) and mastocytoma(P-185 HTR) for JOR and RT-PCR, respectively. Rats anesthetized with thiopental sodium (80mg/kg) were used in the Tooth Pulp stimulation induced JOR. The amplitude of a digastric electromyogram (dEMG) was recorded during the stimulation at an intensity of 1.5 times the threshold for JOR. Apitoxin used in this experiment was diluted with normal saline by 1:1000. Apitoxin was injected intravenously into the test group while normal saline to the control group. However, it was injected directly into the cell of mastocytoma. We referred to base sequence registered in Genbank in designing primers for RT-PCR. The results were as follows; (1)Compared with control group, analgesic effect started to show right after Sprague-Dawely rats were treated with apitoxin($71.50{\pm}8.08$) and lasted for 50 minutes. (2)As a result of the experiment of RT-PCR, we witnessed significant changes in the degree of expression of phospholipase or rate-limiting enzyme of biosynthesis of prostaglandins with $10{\mu}g/ml$ apitoxin.($31.74{\pm}18.98%$, P<0.05) (3)As a result of the experiment of RT-PCR, we witnessed significant changes in the degree of expression of TPH or rate-limiting enzyme in biosynthesis of serotonin with $10{\mu}g/ml$ apitoxin.($131.37{\pm}16.87%$, P<0.05). These results suggest that $10{\mu}g/ml$ apitoxin have the most analgesic effects. This study showed that apitoxin has analgesic effects and held good for 50 minutes. The injection of apitoxin has brought out changes in the degree of expression of phospholipase and TPH. These results strongly suggest that analgesic mechanism by apitoxin is closely related to prostaglandins and serotonin.

• Environmental Engineering Research
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• v.13 no.3
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• pp.125-130
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• 2008

Free ammonia ($NH_3$-N) inhibition of nitrite-oxidizing bacteria (NOB) has been widely studied for partial nitrification (or nitrite accumulation) and denitrification via nitrite ($NO_2^-$-N) as a low-cost treatment of ammonium containing wastewater. The literature on $NH_3$-N inhibition of NOB, however, shows disagreement about the threshold $NH_3$-N concentration and its degree of inhibition. In order to clarify the confusion, a simple and cheap respirometric method was devised to investigate the effect of free ammonia inhibition of NOB. Sludge samples from an autotrophic nitrifying reactor were exposed to various $NH_3$-N concentrations to measure the maximum specific nitrite oxidation rate ($\hat{K}_{NO}$) using a respirometer. NOB biomass was estimated from the yield values in the literature. Free ammonia inhibition of nitrite oxidizing bacteria was reversible and the specific nitrite oxidation rate ($K_{NO}$) decreased from 0.141 to 0.116, 0.100, 0.097 and 0.081 mg $NO_2^-$-N/mg NOB h, respectively, as the $NH_3$-N concentration increased from 0.0 to 1.0, 4.1, 9.7 and 22.9 mg/L. A nonlinear regression based on the noncompetitive inhibition mode gave an estimate of the Inhibition concentration ($K_I$) of free ammonia to be 21.3 mg $NH_3$-N/L. Previous studies gave $\hat{K}_{NO}$ of Nitrobacter and Nitrospira as 0.120 and 0.032 mg/mg VSS h. The free ammonia concentration which inhibits Nitrobacter was $30{\sim}50\;mg$ $NH_3$-N/L and Nitrospira was inhibited at $0.04{\sim}0.08\;mg$ $NH_3$-N/L. The results support the fact that Nitrobacter is the dominant NOB in the reactor. The variations in the reported values of free ammonia inhibition may be due to the different species of nitrite oxidizers present in the reactors. The respirometric method provides rapid and reliable analysis of the behavior and community of the nitrite oxidizing bacteria.