• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.560-571
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• 2019

In the study, used torrefaction method to make sample from organic waste of livestock manure for Biomass-solid refuse fuel feasibility study of torrefied materials. Fallen leaves and sawdust added in torrefaction methods with livestock manure, that additives were used to improve the lower calorific value of livestock manure. During the torrefaction experiment, the reaction temperature was varied from $200^{\circ}C$ to $260^{\circ}C$ and $20^{\circ}C$ to prepare a sample. The reaction time was divided into 15, 30 and 45min to determine the effect of the experimental conditions on the torrified products. The additives were mixed at a ratio of 9:1 and 8:2 (Cow manure: additive) relative to the livestock manure. Through this experiment, it was obtained 3,500 kcal/kg standard product of solid fuel produced in Korea and improved product was obtained by adding additives.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.16-21
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• 2019

This study has its aim to judge both applicability and suitability of recycling of waste soil for the use of farmland amelioration and low-lying farmland reclamation through growth and development experiment and component analysis. As results of physical characteristic evaluation on recycling of waste soil, the classification based on unified soil classification system has investigated as SW and SP affiliation and soil classification has appeared to be a loamy sand. As results of chemical component analysis, pH has appeared to be 7.0~8.4 which is relatively higher than general soil, however, heavy metal has investigated within the 1 region's standard value of soil pollution standards. As results of germination experiment, when using it by mixing recycling soil less than 75%, there is no significant influence on germination, and in the growth and development experiment, when using horticultural bed soil which is mixed with less than 40% of recycling of waste soil, it has confirmed that there is no significance difference with general soil. In case of farmland, the growth disorder of recycling of waste soil rate no more than 40% has shown that it has relatively small influences, and in case of using it by mixing with agricultural soil, it has evaluated to require concrete review of factors which may restrict growth condition including nutrition and pH.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.37-43
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• 2019

This research studied production of lightweight filling production for sink hole restoration utilizing various industrial by-products(2kinds of fly ash, petro-cokes CFBC ash, blast furnace slag fine particle). For this purpose, the mixed raw material properties(compressive strength) behaviors according to the blending ratio of industrial by-products were examined by applying the experimental design method and statistical analysis was performed using the commercial program MINITAB. Compressive strengths of industrial by-products were strongly dependent on blast furnace slag powder. Compressive strength(3days aging) was 3~11MPa depending on the amount of blast furnace slag powder used. The use of CFBC fly ash was evaluated to have the least effect on compressive strength. In addition, the compressive strength and the coefficient of permeability were measured by preparing foamed concrete for the experimental batch 1 condition in the mixture experimental design. In this case, the bulk density is 0.9 to 1.0, the apparent porosity is 30 to 50%, the compressive strength(3days old) is 1 to 2MPa, and the permeability coefficient is $10^{-2}$ to $10^{-3}cm/sec$.

• Journal of the Korea Institute of Building Construction
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• v.19 no.2
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• pp.113-121
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• 2019

Single walled carbon nanotube (SWCNT) has been used as a material for reinforcing various advanced materials because it has superior mechanical properties. However, pure SWCNT that does not have any functional group has a hydrophobic character, and exists as bundles due to the strong Van der Waals attraction between each SWCNT. Due to these reasons, it is very difficult to disperse SWCNTs in the water. In this work, in order to use SWCNT for production of cementitious composites, SWCNT was first dispersed in water to make an aqueous solution. Sodium deoxycholate (DOC) and Sodium dodecyl sulfate (SDS) were chosen as surfactants, and the dosage of DOC and SDS were 2wt% and 1wt%, respectively. Sonication and ultracentrifugation were applied to separate each SWCNT and impurities. Using such processed SWCNT solutions, cement paste was prepared and its shear stress vs. strain rate relationship was studied. The yield stress and plastic viscosity of cement paste were obtained using Bingham model. According to the results in this work, cement pastes made with DOC and SDS showed similar rheological behavior to that of air entrained cement paste. While cement paste made with DOC 2 wt.% SWCNT solution showed similar rheological behavior to that of plain cement paste, cement paste made with SDS 1 wt.% SWCNT solution showed different rheological behavior showing much less yield stress than plain cement paste.

• Journal of the Korea Institute of Building Construction
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• v.19 no.3
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• pp.209-217
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• 2019

EMP (Electromagnetic Pulse) usually means High Power Electromagnetic Wave (HPEM). In the case of the shielding plate against the EMP, there is a possibility of deterioration of the electromagnetic wave shielding performance due to the skill of the constructor, bad construction, deformation of the shielding plate at the connection portion (joint portion). The inefficient use of space due to the separation distance is also pointed out as a problem. Therefore, this study aims to derive the optimum electromagnetic shielding condition by applying ATMSM to concrete as a part of securing electromagnetic wave shielding performance with reflection loss against concrete wall. Experimental parameters included concrete wall thickness and application of Zn-Al ATMSM. For the concrete wall, the wall thickness was 100 to 300mm, which is generally applied, and experimental parameters were set for the application of Zn-Al metal spraying method to evaluate electromagnetic shielding performance. Experimental results showed that as the thickness increases, the electromagnetic shielding performance increases due to the increase of absorption loss. In addition, after the application of Zn-Al ATMSM, the average shielding performance increased by 56.68 dB on average, which is considered to be increased by the reflection loss of the ATMSM. In addition, it is considered that the shielding performance will be better than that when the conductive mixed material and the ATMSM are simultaneously applied.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.40-45
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• 2021

Prior studies of physiologically active substances in grapes have focused only on the fruit, pericarp, and branches, as well as the pulp and seeds. The present study assessed the changes in quercetin-3-O-glucuronide (Q3OG) and flavonol glycoside content using grape leaves from Vitis labruscana B. and V. coignetiae at different growth stages and provided basic data for quality control. Content analysis showed that both varieties differed in Q3OG and flavonol glycoside content by growth stage, and the components were found to be high in the order of fruit, maturation, and coloration. Also, Vitis labruscana B. has a better vascular relaxation effect than Vitis coignetiae. These results suggest that in the use of grape leaves as a functional raw material, Q3OG and flavonol glycosides can be used as indicator components. In addition, if raw materials for each growth stage are mixed in a particular ratio, it will be a way to manage the specific efficacy and content of indicator components.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.3
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• pp.183-205
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• 2021

This systematic review and meta-analysis aimed to analyze the effectiveness of maxillary stabilization splint (SS) therapy to reduce headache (HA) intensity and HA frequency in patients with temporomandibular disorders (TMD)-HA comorbidity. Randomized controlled trials (RCTs) using full-arch coverage, hard resin, and maxillary SS therapy were included. Electronic databases, including Cochrane Library, MEDLINE through PubMed, Web of Science, and EMBASE, were searched. The risk of bias was analyzed based on Cochrane's handbook. The search yielded 247 references up to January 28, 2020. Nine RCTs were included at a high risk of bias. The comparison groups included other splints, counseling, jaw exercises, medications, neurologic treatment, and occlusal equilibration. Four studies reported a statistically significant reduction in HA intensity, and five studies reported significant improvement in HA frequency from baseline at 2-12 months in patients with TMD-HA comorbidity treated with a full-arch hard maxillary SS. HA frequency in tension-type HA (TTH) comorbid with TMD diagnoses of myofascial pain (MFP) or capsulitis/synovitis improved significantly with SS than that with full-arch maxillary non-occluding splint (NOS) in two studies. Comparison groups receiving hard partial-arch maxillary splint nociceptive trigeminal inhibition (NTI) showed statistically significant improvements in HA intensity in patients with mixed TMD phenotypes of MFP and disc displacement comorbid with "general HA." Comparison groups receiving partial-arch maxillary resilient/soft splint (Relax) showed significant improvements in both HA intensity and frequency in patients with HA concomitant with MFP. The meta-analysis showed no statistically significant difference in the improvement of pain intensity at 2-3 months with comparison of the splints (partial-arch soft [Relax], hard [NTI], and full-arch NOS) or splint use compliance at 6-12 months with comparison of the splints (partial-arch Relax and full-arch NOS) versus the SS groups in patients with various TMD-HA comorbidities. In conclusion, although SS therapy showed a statistically significant decrease in HA intensity and HA frequency when reported, the evidence quality was low due to the high bias risk and small sample size. Therefore, further studies are required.

• Journal of the Korean GEO-environmental Society
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• v.12 no.7
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• pp.31-37
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• 2011

Only a few studies have been conducted using reduced slag as recycled material. The reduced slag in electric furnace is produced as a by-product in making a steel and a few applications of the reduced slag as expensive additives and bonding materials or as the stabilized soils was reported. The purpose of this study is to present the feasibility of the reduced slag as recycled material, especially, in a field of civil engineering. In order to achieve the purpose experiments such as SEM and XRF analysis was conducted for the reduced slag in electric furnace. Based on the results various geotechnical experiments were conducted to know engineering properties of slag-soil mixtures. Weathered soils and clay are mixed with reduced slag for various ratios. As the ratio of reduced slag to weathered soil increases, the maximum dry unit weight of the mixture decreased with increasing optimum moisture content. The results indicates that there is no effect on a reduced slag by compaction efforts. The shear strengths of the weathered soil-slag mixtures are slightly higher or similar to those of weathered soils. The permeability of the weathered soil-slag mixtures is similar to that of silty or sandy soils. Therefore, it is possible to use the mixtures as embankment or backfill materials in the fields. The unconfined strength of the mixtures of reduced slag and clay is higher than that of clay and it tends to increase with the curing time. Therefore it can be used to improve the soft ground.

• 교육공학연구
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• v.33 no.1
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• pp.105-135
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• 2017

The purpose of this study is to clarify conceptually the difference of instructional coaching, instructional supervision, and instructional consulting by analyzing their own characteristics. The practices for instructional improvement are common in that fundamental objectives are improvement of instruction and development of teacher's professionalism in instruction. However, each area changed according to the social flow and the demands of the educational field and created a unique activity system. So, in order to get rid of this mixed use of these terms, it is meaningful to distinguish the concepts, attributes, and areas of each activity. The specific study questions were 1) what is the origin of coaching, supervision, and consulting? 2) how are instructional coaching, instructional supervision, and instructional consulting defined in existing research in korea? 3) how can we conceptually distinguish instructional coaching, instructional supervision, and instructional consulting? Based on reviewing various existing studies, First, this study investigated the conceptual origins and lexicons of coaching, supervision, and consulting, respectively, in addition reviewd the prior studies conducted in Korea with regard to instructional coaching, instructional supervision, and instructional consulting, and summarized how each concept is defined according to the researcher. Second, this study compared each two concept with another one. Finally, the existing definitions of instructional coaching, instructional supervision, and instructional consulting were analyzed to find out the inherent and common attributes of each concept. In conclusion, this study suggest that the concept of instructional consulting needs to be redefined to better reflect the characteristics of activities, and that studies that rethink the relationship between instructional coaching and instructional supervision are needed.

• The Journal of Engineering Geology
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• v.30 no.4
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• pp.603-615
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• 2020

The design factors of artificial recharge are determined by considering the hydrogeological characteristics of the aquifer. The optimal design factors for artificial recharge were derived after performing the injection tests step by step for each injection type (vertical well, ditch and mixed type), which were built in the test site of the study area. It was analyzed that the difference in the injection effect according to the diameter of the injection well was not large, and the 100 mm well was evaluated as appropriate in consideration of the availability and economy of land use. Since the injection effect was well maintained even in the upper rock, the depth of the injection well was proposed for the alluvial layer and the upper rock layer. On the other hand, in four cases of filter media in the ditch, it was analyzed that the penetration efficiency and the hydraulic interference effect indicated excellent injection performance when a filter medium of 10 to 30 mm diameter was filled in the ditch. In addition, the proper spacing of the injection wells was analyzed as 9~12 m considering the interference efficiency. The interference efficiency attenuation coefficient per 1 m of hole spacing was calculated to be 1.75% in this area. In the future study, the artificial recharge design factors obtained in this stage are applied and verified on site construction and operation. Also it is expected to contribute to securing water in areas where there is always a lack of water.