• Environmental Engineering Research
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• v.23 no.1
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• pp.92-98
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• 2018

Suitability of aluminium-based water treatment sludge (WTS), a waste product from water treatment facilities, was assessed for removal of heavy metals from an electroplating wastewater which had high concentrations of copper and chromium along with other heavy metals. Batch tests with simulated wastewater in single- and multi-metal solutions indicated the influence of initial pH and WTS dose on removal of six metals namely Cu(II), Co(II), Cr(VI), Hg(II), Pb(II) and Zn(II). In general, removal of cationic metals such as Pb(II), Cu(II) and Zn(II) increased with increase in pH while that of anionic Cr(VI) showed a reduction with increased pH values. Tests with multi-metal solution showed that the influence of competition was more pronounced at lower WTS dosages. Column test with diluted (100 times) real electroplating wastewater showed complete removal of copper up to 100 bed volumes while chromium removal ranged between 78-92%. Other metals which were present in lower concentrations were also effectively removed. Mass balance for copper and chromium showed that the WTS media had Cu(II) and Cr(VI) sorption capacities of about 1.7 and 3.5 mg/g of dried sludge, respectively. The study thus indicates that WTS has the potential to be used as a filtration/adsorption medium for removal of metals from metal-bearing wastewaters.

• Journal of Magnetics
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• v.3 no.4
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• pp.99-104
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• 1998

The $ Sm_2Fe_{17}N_x $materials were prepared by the combination consisting of the HDDR (hydrogenation, disproportionation, desorption, and recombination) process and nitrogenation or by the conventional way consisting of nitrogenation only, and the magnetic and thermomagnetic properties of the materials were investigated. The magnetic characterisation of the prepared $ Sm_2Fe_{17}N_x $ materials was performed using a VSM. Thermal stability of the materials was evaluated using a DTA under Ar gas atmosphere. The thermomagnetic characteristics of the materials were examined using a Sucksmith-type balance. The previously HDDR-treated Sm2Fe17parent alloy was found to be nitrogenated more easily compared to the ordinary $ Sm_2Fe_{17}N_x $alloy. The $ Sm_2Fe_{17}N_x $ material produced by the combination method showed a high coercivity (12.9 kOe) even in the state of coarse particle size (around 60 ${\mu}{\textrm}{m}$). It was also revealed that the $ Sm_2Fe_{17}N_x $ material produced by the material produced by the combination showed an unusual TMA tracing featured with a low and constant magnetisation at lower temperature range and a peak just before the Curie temperature. This thermomagnetic characteristic was interpreted in terms of the competition between two counteracting effects; the decrease in magnetisation due to the thermal agitation at an elevated temperature and the increase in magnetisation resulting from the rotation of magnetisation of the fine grains comparable to a critical single domain size due to the decreased magnetocrystalline anisotropy at an elevated temperature.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.1
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• pp.1-7
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• 2021

The pH dependence of sorption distribution coefficient (Kd) of Np(IV) on MX-80 in Ca-Na-Cl type solution with the ionic strength of 0.3 M, which was similar to one of the reference groundwaters in crystalline rock, was experimentally investigated under the reducing conditions. The overall trend of Kd on MX-80 was independent of pH at 5 ≤ pH ≤ 10 but increased as pH increased at pH ≤ 5. The 2-site protolysis non-electrostatic surface complexation and cation exchange model was applied to the experimentally measured pH dependence of Kd and the optimized surface complexation constants of Np(IV) sorption on MX-80 were estimated. The values of surface complexation constants in this work agreed relatively well with those in the Na-Ca-Cl solution previously evaluated, suggesting that compared to Na+, the competition of Ca2+ with Np(IV) for surface complexation on MX-80 was not much strong in Ca-Na-Cl solution. The sorption model well predicted the pH dependence of Kd values but slightly overestimated the sorption at the low pH region.

• Smart Structures and Systems
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• v.31 no.4
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• pp.383-392
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• 2023

Post-earthquake building condition assessment is crucial for subsequent rescue and remediation and can be automated by emerging computer vision and deep learning technologies. This study is based on an endeavour for the 2nd International Competition of Structural Health Monitoring (IC-SHM 2021). The task package includes five image segmentation objectives - defects (crack/spall/rebar exposure), structural component, and damage state. The structural component and damage state tasks are identified as the priority that can form actionable decisions. A multi-task Convolutional Neural Network (CNN) is proposed to conduct the two major tasks simultaneously. The rest 3 sub-tasks (spall/crack/rebar exposure) were incorporated as auxiliary tasks. By synchronously learning defect information (spall/crack/rebar exposure), the multi-task CNN model outperforms the counterpart single-task models in recognizing structural components and estimating damage states. Particularly, the pixel-level damage state estimation witnesses a mIoU (mean intersection over union) improvement from 0.5855 to 0.6374. For the defect detection tasks, rebar exposure is omitted due to the extremely biased sample distribution. The segmentations of crack and spall are automated by single-task U-Net but with extra efforts to resample the provided data. The segmentation of small objects (spall and crack) benefits from the resampling method, with a substantial IoU increment of nearly 10%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.252-258
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• 1985

An experiment was conducted at the Yeongnam Crop Experiment Station to obtain basic informations about cultural techniques for high yielding by manipulating plant spacing using two rice cultivars, Samgangbyeo (Indica/Japonica type) and Nakdongbyeo (Japonica type), and four plant spacings, 10${\times}$10cm, 20${\times}$20cm 30${\times}$30cm and 40${\times}$40cm, with 4 kinds of seedling number per hill, 1,3,5 and 7, respectively. High photosynthetic efficiency (Eu) exhibited at the Samgangbyeo compared to Nakdongbyeo regardless of plant spacings and seedling numbers. For Samgangbyeo, Eu value was the highest at the 20${\times}$20cm plant spacing and five seedlings and seven seedlings per hill showed high Eu values at 10${\times}$10cm plant spacing and 20${\times}$20cm plant spacing, respectively, while other plant spacings were not significantly differed among seedling numbers. For Nakdongbyeo, however, one seedling plot obtained high Eu value at the 10${\times}$10cm plant spacing while this Eu value increased as the seedling number per hill increased in other plant spacings. There was a high positive correlation between rice grain yield and total competition index for both cultivars while kind of relationships differed in these two cultivars; linear relationship for Samgangbyeo and exponential relationship for Nakdongbyeo, respectively. Competition index between rice hill was more significant than within rice hill for Samgangbyeo while both competition indexs were important for Nakdongbyeo to increase rice yield.

• Korean Journal of Medicinal Crop Science
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• v.7 no.2
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• pp.121-128
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• 1999

This experiment was carried out to establish effective weed control system in the cultivation of Coix lachryma-jobi L. The effect of annual weeds artificially transplanted on the growth of Coix lachryma-jobi L. were that the higher the density of weeds, the lower the yield considerably by reducing number of grains and tillers per plant. Among four weeds of Echinochloa crusgalli galli P. BEAUV., Digitaria sanguinalis $S_{COPOL}$., Chenopodium album L., and Portulaca oleracea L., weed of Portulaca oleracea L. reduced adlay yield most by 182.6kg/10a and it was judged to be the most injurious weed to adlay production. Among four weed control systems, which are one herbicide treatment, one herbicide treatment + one cultivating work with cultivator, two times cultivating work with cultivator and two times hand-weeding, the control system of 'one herbicide treatment + one cultivating work with cultivator' showed the lowest amount of weed growth by 7.34 weeds per $m^2$ in comparison with control plot of 35.00 weeds per $m^2$. Among four weed control systems, the system of 'two times hand-weeding' had much more amount of light penetration in adlay canopy with 791.9 mol than any other systems.

• Korean Journal of Applied Biomechanics
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• v.14 no.3
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• pp.149-163
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• 2004

This study analyzed kinematic variables about the cross step, the delivery and the release for women's javelin athletics recorded over 50m in the 2004 Busan International Athletics Competition. It was used the Kwon3D Motion Analysis Package Ver. 3.1 Program(Kwon, 2000) for analysing the kinematic variables about the distance, the velocity, and the angle, then we had the results as follows; 1 In the Cross step phase, the COG velocity was low because their step length was short. To keep the CM velocity from the approach to the last cross over step contact, the athletes have to keep the longer step length within about 130% of the athletics' height. 2. In the Delivery phase, the athletics' COG height was gradually lower, and the deceleration of the COG was going up. As the same in the cross step, Therefore the athletes have to increase the step length within about 100% of their height, in order to increasing the COG velocity. And it was shown they have to make small angle of the elbow as possible from the right foot contact to the left foot contact in order to being the big acceleration of the upperarm at the release phase. 3. In the release phase, it was shown to being low position of the release point as the COG was low and then the release velocity of the upperarm was low. Specially when the shoulder lean lateral angle is big at the release phase, it was shown they have a excessive release angle. And, when it was shown the high rotation angle of the shoulder, the shoulder was opened forward bigger than the trunk was opened forward. So the transmission of velocity from the proximal segments was a fast change.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.177-182
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• 1989

The plant height, shoot numbers and dry matter weight in both bulrush and rice were increased by high level of nitrogen fertilizer and especially the dry matter weights in both species were sharply increased by high level of nitrogen fertilizer. The plant height, dry matter weight in rice, and shoot, and dry matter weight in bulrush were increased by high level of phosphorus fertilizer. The deficient symptom disappeared with change of low level into high level phosphorus in rice. The plant height, dry matter weight and shoot numbers in rice and bulrush were increased by high level of potassium fertilizer. In the inter-specific competition in bulrush according to various water levels, the plant heights in both species elongated longer with deep water levels, and the plant height and dry matter weight in bulrush were more sharply decreased than in rice by deep water levels. The shoot numbers and dry matter weight were critically dropped above 6-8 cm water level. In case of the shoot numbers for light source, in both species were more decreased in mixed culture than each monoculture. The exserted shoot length and weight in bulrush were larger than those in rice. The shaded shoot dry weight was more decreased in mixed culture than in each monoculture, and the decrement was larger in bulrush than in rice.

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.228-242
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• 2016

This research was conducted for understanding the evergreen forest community structure of the Bijin Island. The island was worth of vegetational value because of the representative warm temperate species such as Castanopsis cuspidata was distribute there. According to the results of community classification by TWINSPAN and DCA, the Bijin Island evergreen forest were classified by 9 communities, such as C. cuspidata, C. cuspidata-Pinus thunbergii, Neolitsea sericea-Camellia japonica, Platycarya strobilacea, Quercus serrata-Decidus broad-leaved, Alnus firma, P. thunbergii. Due to the C. cuspidata, N. sericea, Ca. japonica etc. were still dominated at canopy and under-canopy layer, so the evergreen forest will be sustain current conditions for a while if there is no artificial disturbances that were caused by human. Pl. strobilacea community will be expected to replace N. sericea and also Q. serrata-Decidus broad-leaved community will be changing caused by mutual competition. Normally, in the way of the succession process of the warm temperate forest, P. thunbergii will be expect via deciduous broad-leaved to evergreen forest such as Machilus thunbergii, C. cuspidata var. sieboldii, and N. sericea. In case of species diversity index, P. thunbergii comm.(1.2739), Q. serrata-Decidus broad-leaved comm.(1.2325), Decidus broad-leaved comm.(1.1807), and A. firma comm.(1.0854) are relatively high, while C. cuspidata and N. sericea-Ca. japonica that was dominated by evergreen species at canopy layer and P. thunbergii that was damaged by fire are relatively low(0.7380~0.8416). Soil pH was 4.72~6.33, electric conductance was 0.035~0.128dS/m, and content of organic matter was 3.4~17.4%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.1146-1152
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• 2010

The Korean healthcare industry is rapidly changing along with the competition among hospitals. In the past, hospitals could make profit without designing competitive management strategies. Thus, they did not find importance in listening to customers' voices and identifying their wants. However, nowadays, the increasingly intense competition is encouraging hospitals to seriously consider competitive management strategies and Customer Relationship Management (CRM) activities to gain a competitive advantage and prosper. It tries to compare the expected satisfaction with the satisfaction of out-patient and in-patient and analysis of VOC(Voice of Customer). This survey was done from 27th, April, 2009 to 8th May and each 100 in-patients and out-patients. The paired t-test and descriptive analysis was used to analysis between before and after satisfaction. The result, the replied out-patients were the highest of I.M department, 43% and in-patients, surgery and other department are the highest each 22.0%. Nurses kindness is statistical significant in out-patients. Doctor, Nurse and staff's kindness and rounding service was statistical significant in in-patients. Totally, the satisfaction was lower than expected satisfaction, so the medical care institutions should analyst detailed the patient's satisfaction by VOC.