• Journal of Microbiology and Biotechnology
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• v.24 no.9
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• pp.1245-1253
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• 2014

One-step sulfuric acid saccharification of the red alga Pterocladiella capillacea was optimized, and various detoxification methods (neutralization, overliming, and electrodialysis) of the acid hydrolysate were evaluated for fermentation with the thermotolerant yeast Kluyveromyces marxianus. A proximate composition analysis indicated that P. capillacea was rich in carbohydrates. A significant galactose recovery of $81.1{\pm}5%$ was also achieved under the conditions of a 12% (w/v) biomass load, 5% (v/v) sulfuric acid, $121^{\circ}C$, and hydrolysis for 30 min. Among the various detoxification methods, electrodialysis was identified as the most suitable for fermentable sugar recovery and organic acid removal (100% reduction of formic and levulinic acids), even though it failed to reduce the amount of the inhibitor 5-HMF. As a result, K. marxianus fermentation with the electrodialyzed acid hydrolysate of P. capillacea resulted in the best ethanol levels and fermentation efficiency.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.12
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• pp.38-44
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• 2002

A walking training robot is proposed to provide stable and comfortable walking supports by reducing body weight load partially and a force control of an arm of walking training robot using sliding mode controller is also proposed. The current gait training apparatus in hospital are ineffective for the difficulty in keeping constant unloading level and for the constraint of patients' free walking. The proposed walking training robot effectively unloads body weight during walking. The walking training robot consists of an unloading manipulator and a mobile platform. The manipulator driven by an electro-mechanical linear mechanism unloads body weight in various levels. The mobile platform is wheel type, which allows patients to walt freely. The developed unloading system has advantages such as low noise level, lightweight, low manufacturing cost and low power consumption. A system model fur the manipulator is established using Lagrange's equation. To unload the weight of the patients, sliding mode control with p-control is adopted. Both control responses with a weight and human walking control responses are analyzed through experimental implementation to demonstrate performance characteristics of the proposed force controller.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.2
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• pp.165-173
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• 2007

This paper introduces a new current sharing technique to Interleaved Boost Converter (IBC) using carrier slope control. The IBC is able to boost the input voltage and operates at higher current levels and has various advantages over a single power module. However, how to balance the current each module is still important problem. To solve this problem, the proposed technique can distribute the power and load current equally based on master-slave current sharing method. Unlike a conventional approach, this technique can be extended even though the current stress of switching components at slave modules is significantly smaller than that of the master module. The simulation and the experimental results are presented to show the validity.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.3
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• pp.373-379
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• 2019

Nowadays, the IoT portable electronic devices have become more useful and diverse, so they require various supply voltage levels to operate. This paper presents a DC-DC buck converter with pulse width modulation (PWM) for portable electronic devices. The proposed step-down DC-DC converter consists of passive elements such as capacitors, inductors, and resistors and an integrated chip (IC) for signal control to reduce power consumption and improves ripple voltage with the resolution. The proposed DC-DC converter is simulated and analyzed in PSPICE circuit design platform, and implemented on the prototype PCB board with a Texas Instruments LM5165 IC. The proposed buck converter is showed 92.6% of peak efficiency including a load current range of 4-10 mA, 3.29 mV of the voltage ripple at 5 V output voltage for the supply voltage 12 V. Measured and Simulated power efficiency are made good agreement with each other.

• The Korean Journal of Nuclear Medicine
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• v.11 no.1
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• pp.17-32
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• 1977

The present study was undertaken to evaluate the significance of the insulin and the C-peptide rseponse to oral glucose loads in normal and diabetic subjects and to establish the effects of the obesity. In this study, the authors have measured plasma insulin and C-peptide by means of radioimmunoassay in 10 nonobese normal, 5 obese normal, 13 nonobese moderate diabetic patients, 9 obese moderate diabetic patients and 9 severe diabetic patients. The results obtained were as follows; 1. In 10 nonobese normal subjects, the plasma insulin level at fasting state and at 30, 60, 90, and 120 min after oral glucose loads were $15.7{\pm}3.4,\;48.3{\pm}9.8,\;40.4{\pm}6.7,\;37.4{\pm}6.5\;and\;26.0{\pm}4.2uU/ml(Mean{\pm}S.E.)$ and C-peptide were $1.9{\pm}0.3,\;3.9{\pm}0.6,\;6.3{\pm}0.6,\;5.7{\pm}0.5\;and\;4.0{\pm}0.5ng/ml$. The change of C-peptide was found to go almost parallel with that of insulin and the insulin value reaches to the highest level at 30 min whereas C-peptide reaches to its peak at 60min. 2. The plasma insulin level in 5 obese normal subjects were $38.9{\pm}12.3,\;59.5{\pm}12.3,\;59.2{\pm}17.1,\;56.1{\pm}20.0\;and\;48.4{\pm}17.2uU/ml$ and the C-peptide were $5.5{\pm}0.4,\;6.8{\pm}0.5,\;7.9{\pm}0.8,\;7.9{\pm}0.8\;and\;7.8{\pm}2.0ng/ml$. The insulin response appeared to be greater than nonobese normal subjects. 3. In 13 nonobese moderate diabetic patients, the plasma insulin levels were $27.1{\pm}4.9,\;44.1{\pm}6.0,\;37.3{\pm}6.6,\;35.5{\pm}8.1\;and\;34.7{\pm}10.7uU/ml$ and the C-peptide levels were $2.7{\pm}0.4,\;4.9{\pm}0.7,\;6.5{\pm}0.5,\;7.0{\pm}0.3\;and\;6.7{\pm}1.0ng/ml$. There was little significance compared to nonobese normal groups but delayed pattern is noted. 4. In 9 obese moderated diabetic patients, the plasma insulin levels were $22.1{\pm}7.9,\;80.0{\pm}19.3,\;108.0{\pm}27.0,\;62.0{\pm}17.6\;and\;55.5{\pm}10.1uU/ml$ and the C-peptide levels were $5.2{\pm}0.4,\;8.0{\pm}1.0,\;10.4{\pm}1.6,\;10.4{\pm}1.7\;and\;10.1{\pm}1.0ng/ml$ and its response was also greater than that of nonobese moderate diabetic patients. 5. The plasma insulin concentrations in 9 severe diabetic subjects were $8.0{\pm}3.8,\;12.1{\pm}3.5,\;16.8{\pm}4.6,\;19.6{\pm}5.2\;and\;15.0{\pm}5.0uU/ml$ and the C-peptide levels were $1.6{\pm}0.3,\;2.4{\pm}0.4,\;4.1{\pm}0.6,\;4.0{\pm}0.8\;and\;4.5{\pm}0.7ng/ml$ and the insulin and C-peptide responses were markedly reduced in severe diabetic groups. 6. There were-significant differences between each groups of patients on the magnitude of total insulin or C-peptide areas, the insulinogenic index and the C-peptide index.

• Computers and Concrete
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• v.12 no.2
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• pp.211-228
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• 2013

The structure analyzed in this paper has particular building style and special structural system. It is a rigid-connected twin-tower skyscraper with asymmetrical distribution of stiffness and masses in two towers. Because of the different stiffness between the north and the south towers, the torsion seismic vibration is significant. In this paper, in order to study the seismic response of the structure under both frequent low-intensity earthquakes as well as rare earthquakes at the levels of intensity 7, the analysis model is built and analyzed with NosaCAD. NosaCAD is an nonlinear structure analysis software based on second-development of AutoCAD with ObjectARX. It has convenient modeling function, high computational efficiency and diversity post-processing functions. The deformations, forces and damages of the structure are investigated based on the analysis. According to the analysis, there is no damage on the structure under frequent earthquakes, and the structure has sufficient capacity and ductility to resist rare earthquakes. Therefore the structure can reach the goal of no damage under frequent earthquakes and no collapse under rare earthquakes. The deformation of the structure is below the limit in Chinese code. The time sequence and distribution of damages on tubes are reasonable, which can dissipate some dynamic energy. At last, according to forces, load-carrying capacity and damage of elements, there are some suggestions on increasing the reinforcement in the core tube at base and in stiffened stories.

• International Journal of Computer Science & Network Security
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• v.21 no.12spc
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• pp.696-702
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• 2021

Informatization of early childhood education in the EU occurs in the context of the use of ICT as a means of sharing experiences, practices in the education and training of preschool children, communication, both at the national level and locally - within educational institutions, as a means of document management, search, data processing and information for the management of early childhood educational institutions, and planning activities for these institutions. This article aims to identify the features of the informatization of early childhood education in EU countries. Results. The countries of the EU have different levels of workload on the staff of early childhood education institutions, which is caused by different numbers of preschoolers and workforce. The greatest load on the staff in France due to a large number of preschoolers, which, despite the reduction, remained the highest among all the countries. By comparison, Poland's significant workload is mitigated by the size of its workforce. With almost equal numbers of staff in Poland and Germany, the countries differ significantly in the number of preschoolers. The countries also have different funding mechanisms for early childhood education, which determines the potential for digitalization. In France, total spending on early childhood education has grown the least (by 11 % between 2012 and 2018), in Poland by 51 %, in the Czech Republic by 44 %, and in Germany by 49%. In France, 100 % is funded by the government, in Poland 78 % is funded by the government, in the Czech Republic and Germany 87 % and 85 % respectively is funded by the government. The results of the survey of teachers' training in the use of ICTs and the level of specialists' readiness to use them in their studies indicate a mismatch between education and the practice of using technology. At the same time, given the high level of professional training of teachers in the use of technology in education, a low level of practice of ICT use in teaching preschool children was revealed. Teachers require professional development of ICT skills.

• Journal of the Korean Geotechnical Society
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• v.23 no.12
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• pp.61-73
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• 2007

As a part of Load and Resistance Factor Design(LRFD) code development in Korea, in this paper an intensive reliability analysis was performed to evaluate reliability levels of the two static bearing capacity methods for driven steel pipe piles adopted in Korean Standards for Structure Foundations by the representative reliability methods of First Order Reliability Method(FORM) and Monte Carlo Simulation(MCS). The resistance bias factors for the two static design methods were evaluated by comparing the representative measured bearing capacities with the design values. In determination of the representative bearing capacities of driven steel pipe piles, the 58 data sets of static load tests and soil property tests were collected and analyzed. The static bearing capacity formula and the Meyerhof method using N values were applied to the calculation of the expected design bearing capacity of the piles. The two representative reliability methods(FORM, MCS) based computer programs were developed to facilitate the reliability analysis in this study. Mean Value First Order Second Moment(MVFOSM) approach that provides a simple closed-form solution and two advanced methods of FORM and MCS were used to conduct the intensive reliability analysis using the resistance bias factor statistics obtained, and the results were then compared. In addition, a parametric study was conducted to identify the sensibility and the influence of the random variables on the reliability analysis under consideration.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.605-612
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• 2000

Four young swamp buffalo cows of similar age ranging in weight between 280 to 380 kg and trained to do physical work were used in a study to determine energy and protein requirements for draught using a $4{\times}4$ Latin square designed experiment. The experiment consisted of field trials employing 4 levels of work load, e.g. no work as control, and loads amounting 450 to 500 Newton (N) pulled continuously for 1, 2 and 3 h daily for 14 consecutive days. Cows were fed king grass (Penisetum purpuroides) ad libitum and were subjected to materials balance trials. Body composition was estimated in vivo by the body density method and daily energy expenditure (EE) was calculated from ME minus retained energy (RE). The results show that EE while not working ($EE_{resting}$) was $0.42kgW^{0.75}MJ/d$ and maintenance ME ($ME_m$) was $0.37kgW^{0.75}MJ/d$. ME requirement increased to 1.65 times maintenance for the work of 3 hours. The energy expended for doing exercise ($E_{exercise}$) was 9.56, 20.0 and 25.86 MJ/cow for treatments 1, 2 and 3 II, respectively. Fat retention was absent in all groups of working cows, but protein retention was only negative for cows undertaking 3 h work. The relationship between $E_{exercise}$ (MJ), work load (F, kN), work duration (t, h) and body mass (W, kg) was found to be: $E_{exercise}=(0.003F^{1.43}t^{0.93})/W^{0.09}MJ$. The maintenance requirement for digestible protein was $2.51kgW^{0.75}g/d$, whereas digestible protein for growth ($DP_{growth}$) and for work ($DP_{work}$) followed the equations: $DP_{growth}=[(258+1.25W^{0.75}){\Delta}Wkg/d]g$ and $DP_{work}=[12.59e^{0.95t}]g$, respectively The coefficients a, b and c for the calculation of $E_{exercise}$ components according to the Lawrence equation were found to be 2.56 J/kgW.m, 5.2 J/kg load carried.m and 0.29, respectively, thus efficiencies to convert ME into work were 0, 16.09, 27.3 and 32.44% for control, 1, 2 and 3 h/d work, respectively. ME and DP requirements for a 250 to 400 kg working buffalo cow allowing to growth up to 0.5 kg/d are presented.

• Journal of Preventive Medicine and Public Health
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• v.13 no.1
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• pp.3-12
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• 1980

Certain heavy metals which may lead peoples to poisonous status are widely used in industry and their uses have been increasing along with rapid industrialization of this country. Such an increasement of metal uses aggravates the status of environmental pollution affecting foodstuffs which are the most important life supporting factor of animal and humanbeing. Concerning the safety measures to minimize food-borne transmission of such hazardous metals, surveillance is the backbone of them and probably more so with a potential problem such as intoxication. Theoretically, this surveillance should include the determination of levels of heavy metal toxicants in foods, the determination of food consumption patterns and typical total diet, and the estimation of total load of the metal contaminant from all sources of exposure including air, water, and occupational sources. In recent year, actually, such estimates on the total daily intake of some heavy metals from foods have been made in several developed countries and a wide variation of date by season, locality, and research method was recognized. Also in this country, this kind of research data is vitally needed to make up for the serious shortage or lack of references to estimate the total amount of heavy metal intake of the people. In this study, a modification model for estimation of the total daily intake of cadmium copper, nickel, zinc, and lead through foods was applied and concentrations of the above metals in crops cultivated in this country were measured with atomic absorption spectro photometer to get the following results. 1. Level of heavy metal concentration in crops Generally, the levels of such metals in essential crops such as rice, cucumber, radish. chinese cabbage, apple, pear, grape, and orange are similar or lower than those in Japan and other developed countries. By the way, a striking result on cadmium concentration was increasement of its concentration in rice from $0{\sim}0.035ppm$ in 1970 to 0.11ppm in this study. However, the value is still far below the. Japanese Permissible Lebel of 1.0ppm. 2. Estimation of total daily intake per capita from foods A new model for estimation was devised utilizing levels of metal concentration in foods, amount of food consumed, and other food factors. Based on the above method, the daily intake of cadmium was estimated to be $70.53{\mu}g/man/day$ in average which was as high as the Limit Value of ILO/WHO(up to $71.4{\mu}g/man/day$). Also, 3.89mg of Zinc, 1.65mg of cuppor, 0.32mg of lead were given as the total daily intake per capita by this research. 3. Efficacy of washing or skinning to decrease the amount of metals in crops After washing the crops sufficiently with commercial linear alkylate sulfonate, the concentration of heavy metals could be reduced to $50{\sim}80%$ showing decreasement rate of $20{\sim}50%$. Also, after skinning the fruits, decreasement rate of the heavy metal concentration shelved $0{\sim}50%$.