• Horticultural Science & Technology
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• v.34 no.1
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• pp.77-83
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• 2016

The measurement of total fresh weight of plants provides an essential indicator of crop growth for monitoring production. To measure fresh weight without damaging the vegetation, image-based methods have been developed, but they have limitations. In addition, the total plant fresh weight is difficult to measure directly in hydroponic cultivation systems because of the amount of nutrient solution. This study aimed to develop a real-time, precise method to measure the total fresh weight of Romaine lettuce (Lactuca sativa L. cv. Asia Heuk Romaine) with growth stage in a plant factory using a nutrient film technique. The total weight of the channel, amount of residual nutrient solution in the channel, and fresh shoot and root weights of the plants were measured every 7 days after transplanting. The initial weight of the channel during nutrient solution supply (Wi) and its weight change per second just after the nutrient solution supply stopped were also measured. When no more draining occurred, the final weight of the channel (Ws) and the amount of residual nutrient solution in the channel were measured. The time constant (${\tau}$) was calculated by considering the transient values of Wi and Ws. The relationship of Wi, Ws, ${\tau}$, and fresh weight was quantitatively analyzed. After the nutrient solution supply stopped, the change in the channel weight exponentially decreased. The nutrient solution in the channel slowly drained as the root weight in the channel increased. Large differences were observed between the actual fresh weight of the plant and the predicted value because the channel included residual nutrient solution. These differences were difficult to predict with growth stage but a model with the time constant showed the highest accuracy. The real-time fresh weight could be calculated from Wi, Ws, and ${\tau}$ with growth stage.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.2
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• pp.181-189
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• 2021

Purpose: The purpose of this study is to investigate the stress response and sleep state of the new patients who visit the hospital for prosthodontic treatment due to tooth loss to make reference to further treatment direction. Materials and methods: Examinations, consultations, and surveys were conducted on 236 patients (94 males, 142 females, and 24-86 years old), who newly registered at the department of prosthodontics at Pusan national university hospital, for 2 years from 2018. The number of remaining teeth, edentulous arch, possibility of mastication, and future prosthetic treatment directions were recorded. The visual analogue scale (VAS), stress response inventory (SRI) and Insomnia severity index (ISI) were used as tools to measure patient's subjective discomfort, stress response, and sleep status. Results: Among the entire prosthodontic patient group, the average value of 'fatigue' was significantly higher among the 7 items of SRI, and the value of 'aggression' was significantly lower (P<.001). There are a significant difference between the edentulous and full dentition in the oral discomfort value measured by VAS (P=.004). In cases where less than 20 teeth remain, mastication is impossible, and patients who are planning treatment with removable prostheses, VAS value and 'depression' and 'fatigue' values in SRI were higher than those in the reverse case (P<.05). The patients showed severe level in VAS value have high value of 'tension', 'somatization', 'depression', 'fatigue'and 'frustration'in SRI than non-serious patients (P<.05). Clinical insomnia occurred in 11.4% of all patients, and women had significantly lower sleep quality than men (P=.044). Patients with insomnia showed significantly higher scores on the VAS value and all 7 SRI items than those of normal sleepers (P<.05). Conclusion: The new prosthetics had high 'fatigue' value among the 7 items of SRI. The oral condition, number of residual teeth and mastication function and clinical insomnia affected oral discomfort and the stress response.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.98-103
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• 2014

Purpose: The effective half life of I-131 is useful to calculate radiation dose, period of hospitalization, and exposure dose of surrounding people from patient. However, it is difficult to measure. This study estimates the effective half life in whole body and thyroid in using of value of residual radioactivity obtained from the early and delay images of Dual time I-131 whole body scan. Also, the correlations between the effective half life and serum creatinine, GFR, and administration dose were investigated in this study. Materials and Methods: The targets were 50 patients administration high dose of I-131 from February to August in 2013, having normal range of serum creatinine and over $30{\mu}IU/mL$ of TSH levels. After administration radioactive I-131, the early scan in the 3rd day and the delay scan in the 5-6th days were performed. To measure the residual radioactivity in the whole body and thyroid, ROI was set and then background radioactivity was corrected to estimate. The effective half life was estimated by calculating the ratio of measured values between the early and delay images. To compare the effective half lives of the whole body and thyroid, it was analyzed by Independent t-test, and each correlation of the effective half life, GFR, serum creatinine, and the dose of administration were analyzed by calculating the pearson's correlation coefficient. All of the analysis were determined to be statistically significant when P<0.05. Results: The effective half life of the whole body was $17.06{\pm}5.50$ hours and of the thyroid was $17.22{\pm}5.41$ hours. The two effective half life did not show significant difference (P=0.887). As the value of GFR was increased, the effective half life of whole body (r=-0.407, P=0.003) and of thyroid (r=-0.473, P=0.001) were significantly decreased; as the value of serum creatinine was increased, the effective half life of whole body (r=0.309, P=0.029) and of thyroid (r=0.371, P=0.008) were significantly increased. In the administration dose, effective half life did not have correlations. Conclusion: The effective half life of I-131 of patients treated for their thyroids were estimated only by using the images of Dual time I-131 whole body scan. Also, the correlations with the effective life, GFR, and serum creatinine were examined. This study might be utilized for a study on optimization for the period of hospitalization of patients treated by high dose of I-131 and on evaluation for internal absorbed dose of MIRD schema in application of the effective half life.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.636-642
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• 2011

The effect of different rates of ethanol additive on fermentation quality of napiergrass (Pennisetum purpureum) and residual water soluble carbohydrate were studied in the experiment. The addition rate of ethanol was 0%, 1.5%, 2.5%, 3.5%, 4.5% on fresh weight of napiergrass. The laboratory silos were kept in the room, then were opened on 1, 3, 5, 7, 14, 30 days after ensiling and the changes of silage quality were analyzed, respectively. There was a fast and large reduction in pH from the 5th day of ensiling to below 4.2 except for the 4.5% treatment. After five days the pH of silage decreased slowly and the pH of the ethanol additions was lower than the control. Lactic acid content of ethanol treatments increased significantly (p<0.05) from the 5th day of ensiling, reaching the highest value on either the 7th day or 14th day. The ethanol additive inhibited the break down of silage protein and the ammonia nitrogen content of ethanol addition silage was significantly (p<0.05) lower than the control after 30 days of ensiling. Within the initial first day of ensiling the water soluble carbohydrate content declined quickly. The efficiency of water soluble carbohydrate usage was higher in silage with ethanol than in the control. The acetic acid of ethanol treatment was significantly (p<0.05) lower than control on first and 14th day, but there was no significant (p>0.05) difference among the ethanol addition silages. The volatile fatty acids content of silage increased gradually from the first day of ensiling and reached the peak on 14th day or 30th day and the content of ethanol addition treatment was significantly (p<0.05) lower than the control. The experimental results indicated that adding ethanol inhibited the use of protein and water soluble carbohydrate of aerobic bacteria and reduced the silage losses during the early stage of ensiling and thus supplied more fermentation substrate for lactic acid bacteria and improved the fermentation quality of napiergrass.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.359-367
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• 2014

Drought index can be used to implement an early warning system for drought and to operate a drought monitoring service. In this study, an approach was examined to determine agricultural drought index (ADI) at high spatial resolution, e.g., 270 m. The value of ADI was calculated based on soil water balance between supply and demand of water. Water supply is calculated by the cumulative effective precipitation with the application of the weight to the precipitation from two months ago. Water demand is derived from the actual evapotranspiration, which was calculated applying a crop coefficient to the reference evapotranspiration. The amount of surface runoff on a given soil type was also used to calculate soil residual moisture. Presence of drought was determined based on the probability distribution in the given area. In order to assess the reliability of this index, the amount of residual moisture, which represents severity of drought, was compared with measurements of soil moisture at three experimental between July 2012 and December 2013. As a result, the ADI had greater correlation with measured soil moisture compared with the standardized precipitation index, which suggested that the ADI would be useful for drought warning services.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.7
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• pp.4835-4841
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• 2015

The effect of particle size and compaction pressure on the thermoelectric properties of n-type $FeSi_2$ was investigated. The starting powders with various particle size were pressed into a compact (compaction pressure; $70{\sim}220kg/cm^2$). The compact specimens were sintered at 1473 K for 7 h and annealed at 1103 K for 100 h under Ar atmosphere to transform to the semiconducting ${\beta}$-phase. The microstructure and phases of the specimens were observed by SEM, XRD and EDS. The electrical conductivity and Seebeck coefficient were measured simultaneously for the same specimen at r.t.~1023 K in Ar atmosphere. The electrical conductivity increased with decreasing particle size and hence the increases of relative density of the sintered body and the amount of residual metallic phase ${\varepsilon}$-FeSi due to a increase of the electrical conductivity. The Seebeck coefficient exhibited the maximum value at about 700~800 K and decreased with decreasing particle size. This must be due to a increase of residual metallic phase ${\varepsilon}$-FeSi. On the other hand, the change of compaction pressure appeared to have little effect on the thermoelectric properties. Consequently, the power factor would be affected more by particle size than compaction pressure.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.484-490
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• 2013

This study was conducted to develop a simulation model for estimating the amount of such products as round wood, dimension lumber and the residual wood biomass produced by processing the individual trees of Larix kaempferi. In the model, the stem volume is assessed using the taper equations of the species to estimate the stem forms. Then, the model simulates the conversion processes of logs to round wood or lumber and assesses the maximum amount of the wood products by the lumber dimensions or round wood size. Also the model provides information on the amount of residuals for kerf and slabs produced on the conversion processes for sawn timber or round wood. According to the results of an application of the model to a L. kaempferi process, the trees greater than 12 cm of DBH can be converted to logs for lumber or round wood production. For the trees, of which DBH is available for log conversion, the maximum amount of final products by dimensions were analyzed. In this analysis, production of the bigger dimension lumber was assumed to be preferred to that of the smaller or round wood. This model can be used for assesment of forest economic value through estimation of merchantable volume for the trees, and assessment of mill residues which has the potential to provide significant amount of feedstock for bioenergy production as well.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.2
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• pp.155-163
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• 2014

Total concentration and chemical speciation of trace metals (Cu, Pb, Zn, Cd, and Ni) were determined to evaluate pollution level and potential ecological risk in surface sediments of the Masan Bay. The results showed that the trace metal concentrations, except for Ni, were high in the inner Masan Bay. Based on the chemical speciation of metals in sediments, the percentage of total concentrations of Cd and Pb in non-residual fraction was 92% and 88%, respectively, indicating that these metals originated mainly from anthropogenic sources. However, Ni (70%) was dominant in residual fraction. Pollution load index (PLI) and ecological risk index (ERI) values in the inner bay indicate the presence of anthropogenic pollution and considerable-moderate ecological risk, respectively. Ecological index (Ei) value for Cd was high at most stations in the Masan Bay, and Cd content was the highest in acid soluble fraction, which presents the highest ecological risk. The results obtained in this study indicate that Cd presents a high potential ecological risk to benthic biota in the Masan Bay.

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.44-49
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• 2007

The quality characteristics of strawberry jam containing different levels of sugar alcohols, such as xylitol, sorbitol and maltitol were compared with jam containing 35% of sugar only. Addition of 10-30% of xylitol did not influence pH and total acidity. The intensity of redness and amount of residual anthocyanin were increased according to increase of levels of xylitol, which showed a positive effect on color. However, the addition of more than 10% of xylitol resulted in negative changes in hardness and spreadmeter values. These and consumer preference results showed that the optimum amount of xylitol was less than 10%. Substituting sugar with 10% of xylitol and 25% of sorbitol, 10% of xylitol and 25% of maltitol or 10% of xylitol and 12.5% of sorbitol and maltitol did not change the pH, total acidity, hardness or spreadmeter value, but the redness and the amount of residual anthocyanin were still increased by these ratios. The most preferred ratio according to the sensory test was 10% of xylitol with 12.5% of sorbitol and maltitol each.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.6
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• pp.115-121
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• 2013

This paper related with the DSE-MMA (Dithered Sign-Error MMA) that is the simplification of computational arithmetic number in blind equalization algorithm in order to compensates the intersymbol interference which occurs the passing the nonlinear communication channel in the presence of the band limit and phase distortion. The SE-MMA algorithm has a merit of H/W implementation for the possible to reduction of computational arithmetic number using the 1 bit quantizer in stead of multiplication in the updating the equalizer tap weight. But it degradates the overall blind equalization algorithm performance by the information loss at the quantization process compare to the MMA. The DSE-MMA which implements the dithered signed-error concepts by using the dither signal before qualtization are added to MMA, then the improved SNR performance which represents the roburstness of equalization algorithm are obtained. It has a concurrently compensation capability of the amplitude and phase distortion due to intersymbol interference like as the SE-MMA and MMA algorithm. The paper uses the equalizer output signal, residual isi, MD, MSE learning curve and SER curve for the performance index of blind equalization algorithm, and the computer simulation were performed in order to compare the SE-MMA and DSE-MMA applying the same performance index. As a result of simulation, the DSE-MMA can improving the roburstness and the value of every performance index after steady state than the SE-MMA, and confirmed that the DSE-MMA has slow convergence speed which meaning the reaching the seady state from initial state of adaptive equalization filter.