• The Journal of KAIRB
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• v.6 no.1
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• pp.5-16
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• 2024

Purpose: The purpose of this study is to investigate the current status of pediatric assent in nationwide hospitals and to assess the children's comprehension for pediatric assent by interviewing pediatricians/pediatric neurologists to determine whether children of the age (elementary and middle school students) can understand the purpose, risks, benefits, and concepts of voluntary participation in clinical research described in the assent form, and to help improve the administrative efficiency of multicenter clinical trials. Methods: The status of pediatric assent was surveyed online using Google Forms at 141 university hospitals with administrative staff who are members of the Institutional Review Board (IRB) administrative staff subcommittee with in Korean Association of Institutional Review Boards (KAIRB). Additionally, face-to-face interviews were conducted with 7 pediatricians/pediatric neurologists. Survey and interview responses were summarized using descriptive statistics. Results: Out of the 141 institutions surveyed, 35 institutions (24.8%) responded. Among them, 30 institutions (85.7%) reported having age criteria for acquiring pediatric assent forms in the case of children. The age range for pediatric assent acquisition have been from 7 years old to 12 years old (15 institutions, 50%), and from 7 years old to 15 years old (7 institutions, 23.3%). Nine institutions (25.7%) have had criteria for obtaining both parents' consent in cases involving the participation of children. Nineteen institutions (54.3%) have had checklists or guidelines available for use by IRB members in study protocols involving vulnerable research subjects. Three pediatricians/pediatric neurologists have believed that upper-grade elementary school students (5th-6th grade) could comprehensively understand informed consent forms. Two have believed that middle school students would be able to understand them if they included personal information. Two pediatricians/pediatric neurologists have believed that even lower-grade elementary school students (1st-4th grade) could understand the explanations if they were made simpler. Conclusion: It is suggested that not only elementary school students (7-12 years old) but also middle school students (13-15 years old) should receive pediatric assent forms, as it would facilitate a comprehensive understanding of the forms. To enhance the comprehension of assent form content, it is necessary to use age-appropriate words, language, and expressions in the forms hospital. It is also recommended to create comics or videos to make the content of the assent forms more accessible for children.

• Journal of Animal Science and Technology
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• v.49 no.4
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• pp.459-470
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• 2007

Domestically, finishing pigs are marketed at 110 kg on an average. However, it is thought to be feasible to increase the market weight to 120kg or greater without decreasing the carcass quality, because most domestic pigs for pork production have descended from lean-type lineages. The present study was undertaken to investigate the growth efficiency and profitability of ‘high’-market wt pigs and the physicochemical characteristics and consumers' acceptability of the high-wt carcass. A total of 96 (Yorkshire × Landrace) × Duroc-crossbred gilts and barrows were fed a finisher diet ad laibtum in 16 pens beginning from 90-kg BW, after which the animals were slaughtered at 110kg (control) or ‘high’ market wt (135 and 125kg in gilts & barrows, respectively) and their carcasses were analyzed. Average daily gain and gain:feed did not differ between the two sex or market wt groups, whereas average daily feed intake was greater in the barrow and high market wt groups than in the gilt and 110-kg market wt groups, respectively(P<0.01). Backfat thickness of the high-market wt gilts and barrows corrected for 135 and 125-kg live wt, which were 23.7 and 22.5 mm, respectively, were greater (P<0.01) than their corresponding 110-kg counterparts(19.7 & 21.1 mm). Percentages of the trimmed primal cuts per total trimmed lean (w/w), except for that of loin, differed statistically (P<0.05) between two sex or market wt groups, but their numerical differences were rather small. Crude protein content of the loin was greater in the high vs. 110-kg market group (P<0.01), but crude fat and moisture contents and other physicochemical characteristics including the color of this primal cut were not different between the two sexes or market weights. Aroma, marbling and overall acceptability scores were greater in the high vs. 110-kg market wt group in sensory evaluation for fresh loin (P<0.01); however, overall acceptabilities for cooked loin, belly and ham were not different between the two market wt groups. Marginal profits of the 135- and 125-kg high-market wt gilt and barrow relative to their corresponding 110-kg ones were approximately -35,000 and 3,500 wons per head under the current carcass grading standard and price. However, if it had not been for the upper wt limits for the A- and B-grade carcasses, marginal profits of the high market wt gilt and barrow would have amounted to 22,000 and 11,000 wons per head, respectively. In summary, 120～125-kg market pigs are likely to meet the consumers' preference better than the 110-kg ones and also bring a profit equal to or slightly greater than that of the latter even under the current carcass grading standard. Moreover, if only the upper wt limits of the A- & B-grade carcasses were removed or increased to accommodate the high-wt carcass, the optimum market weights for the gilt and barrow would fall upon their target weights of the present study, i.e. 135 and 125 kg, respectively.

• Ocean and Polar Research
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• v.35 no.4
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• pp.407-414
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• 2013

One of the most important challenges facing the Spirulina mass cultivation industry is to find a way to reduce the high production costs involved in production. Although the most commercial medium (Zarrouk's medium) for Spirulina cultivation is too expensive to use, it contains higher amount of $NaHCO_3$ (16.80 g $L^{-1}$), trace metals and vitamin solutions. The purpose of this study was to increase the efficiency of Spirulina platensis biomass production by developing a low-cost culture medium at an isolated tropical island such as Chuuk State, Federated States of Micronesia (FSM). This study set out to formulate a lowcost medium for the culture of S. platensis, by substituting nutrients of Zarrouk's medium using fertilizer- grade urea and soil extract with a different concentration of carbon source under natural weather condition. In order to select a low-cost culture medium of S. platensis, 10 culture media were prepared with different concentrations of nitrogen (urea and $NaNO_3$) and $NaHCO_3$. The highest maximum specific growth rate (${\mu}max$) and mass production were 0.50 $day^{-1}$ and 1.05 g $L^{-1}$ in modified medium ($NaHCO_3$ 7.50 g $L^{-1}$, urea 2.00 g $L^{-1}$ without $NaNO_3$) among all the synthesized media. Protein (56.14%) and carbohydrate (16.21%) concentrations of the lyophilized standard samples were estimated with highest concentration of glutamic acid (14.93%). This study revealed that the use of a low concentration of urea and $NaHCO_3$ with soil extract was an affordable medium for natural mass cultivation in the FSM.

• Journal of Energy Engineering
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• v.24 no.2
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• pp.120-128
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• 2015

This study reports the combustion characteristics, such as burner temperature and the concentration of exhausted gas ($O_2$, $CO_x$, $NO_x$) due to the different types and pitches of the fuel supply feeder of the wood pellet boiler. The 1st grade wood pellets composed of mainly larch have been used for the experiment. In case of using the spring feeder, mean temperature of burner was approximately $821.76^{\circ}C$, and the mean concentration of oxygen, carbon monoxide, carbon dioxide and nitrogen oxide were approximately 8.88%, 93.35ppm, 12.15% and 139.83 ppm, respectively. The test result with the spring feeder was shown to approach the condition of complete combustion compared to that of a screw feeder and were in good agreement with authentication judgement standard. Furthermore, the combustion efficiency was improved according to the growth of screw pitch. The control of air flow rate from the blower and ventilator is needed to achieve the complete combustion.

• Steel and Composite Structures
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• v.47 no.1
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• pp.91-102
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• 2023

To study the evaluation standard and control limit of mortar filling layer void length, in this paper, the train sub-model was developed by MATLAB and the track-bridge sub-model considering the mortar filling layer void was established by ANSYS. The two sub-models were assembled into a train-track-bridge coupling dynamic model through the wheel-rail contact relationship, and the validity was corroborated by the coupling dynamic model with the literature model. Considering the randomness of fastening stiffness, mortar elastic modulus, length of mortar filling layer void, and pier settlement, the test points were designed by the Box-Behnken method based on Design-Expert software. The coupled dynamic model was calculated, and the support vector regression (SVR) nonlinear mapping model of the wheel-rail system was established. The learning, prediction, and verification were carried out. Finally, the reliable probability of the amplification coefficient distribution of the response index of the train and structure in different ranges was obtained based on the SVR nonlinear mapping model and Latin hypercube sampling method. The limit of the length of the mortar filling layer void was, thus, obtained. The results show that the SVR nonlinear mapping model developed in this paper has a high fitting accuracy of 0.993, and the computational efficiency is significantly improved by 99.86%. It can be used to calculate the dynamic response of the wheel-rail system. The length of the mortar filling layer void significantly affects the wheel-rail vertical force, wheel weight load reduction ratio, rail vertical displacement, and track plate vertical displacement. The dynamic response of the track structure has a more significant effect on the limit value of the length of the mortar filling layer void than the dynamic response of the vehicle, and the rail vertical displacement is the most obvious. At 250 km/h - 350 km/h train running speed, the limit values of grade I, II, and III of the lengths of the mortar filling layer void are 3.932 m, 4.337 m, and 4.766 m, respectively. The results can provide some reference for the long-term service performance reliability of the ballastless track-bridge system of HRS.

• Clean Technology
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• v.27 no.4
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• pp.332-340
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• 2021

With the recent reinforcement of emission standards, it is necessary to make efforts to reduce NOx from air pollutant-emitting workplaces. The NOx reduction method mainly used in industrial facilities is selective catalytic reduction (SCR), and the most commercial SCR catalyst is the ceramic honeycomb catalyst. This study was carried out to reduce the NOx emitted from steel plants by applying De-NOx catalyst coated on metallic monolith. The De-NOx catalyst was synthesized through the optimized coating technique, and the coated catalyst was uniformly and strongly adhered onto the surface of the metallic monolith according to the air jet erosion and bending test. Due to the good thermal conductivity of metallic monolith, the De-NOx catalyst coated on metallic monolith showed good De-NOx efficiency at low temperatures (200 ~ 250 ℃). In addition, the optimal amount of catalyst coating on the metallic monolith surface was confirmed for the design of an economical catalyst. Based on these results, the De-NOx catalyst of commercial grade size was tested in a semi-pilot De-NOx performance facility under a simulated gas similar to the exhaust gas emitted from a steel plant. Even at a low temperature (200 ℃), it showed excellent performance satisfying the emission standard (less than 60 ppm). Therefore, the De-NOx catalyst coated metallic monolith has good physical and chemical properties and showed a good De-NOx efficiency even with the minimum amount of catalyst. Additionally, it was possible to compact and downsize the SCR reactor through the application of a high-density cell. Therefore, we suggest that the proposed De-NOx catalyst coated metallic monolith may be a good alternative De-NOx catalyst for industrial uses such as steel plants, thermal power plants, incineration plants ships, and construction machinery.