• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.321-326
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• 2022

In this study, cogeneration power plants that use biomass as a raw material to convert them into energy have recently received a lot of attention worldwide and are gradually increasing in South Korea. Therefore, in order to confirm the possibility of using the generated floor material as a fine aggregate for concrete, properties and stability evaluation experiments were performed. Compared to standard sand, the compressive strength of wood chip aggregate was improved by 11 % to 111 %, the length change rate was 89 %, and the waste processing test results met all criteria for hazardous substances. All of these are satisfied, and it is judged that the floor materials by the cogeneration power plant can be used as a fine aggregate for concrete.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.145-155
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• 2021

With the recent rapid improvement in the standards of life and westernization of dietary lifestyles, the consumption of high-calorie diets such as high-fat and high-protein red meat and instant foods has increased, while less vegetables containing dietary fiber are consumed. In addition to that, stress, erroneous dietary behaviors, and contaminated environments are linked to the risk of developing ulcerative colitis, which is on the rise. Another cause of ulcerative colitis is that involve laxative abuse, including repeated, frequent use of laxatives, and include such conditions as deteriorated bowel function, irritable bowel syndrome, diarrhea, intestinal inflammation, etc. The present study aimed to investigate the comparative evaluation of pharmacological efficacy between sulfasalazine alone and combination with herbal medicine on dextran sodium sulfate (DSS)-induced UC in mice. Balb/c mice received 5% DSS in drinking water for 7 days to induce colitis. Animals were divided into five groups (n = 9): group I-normal group, group II-DSS control group, group III-DSS + sulfasalazine (30 mg/kg), group IV-DSS + sulfasalazine (60 mg/kg), group V-DSS + sulfasalazine (30 mg/kg) + Radish Extract mixture (30 mg /kg) (SRE). DSS-treated mice developed symptoms similar to those of human UC, such as severe bloody diarrhea and weight loss. SRE supplementation, as well as sulfasalazine, suppressed colonic length and mucosal inflammatory infiltration. In addition, SRE treatment significantly reduced the expression of pro-inflammatory signaling molecules through suppression both mitogen-activated protein kinases (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways, and prevented the apoptosis of colon. Moreover, SRE administration significantly led to the up-regulation of antioxidant enzyme including SOD and Catalase. This is the first report that Radish extract mixture combined with sulfasalazine protects against experimental UC via the inhibition of both inflammation and apoptosis, very similar to the standard-of-care sulfasalazine.

• Fashion & Textile Research Journal
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• v.23 no.2
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• pp.226-236
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• 2021

The purpose of this study was to classify the torso shape based on abdominal protrusion caused by changes in the physical characteristics of middle-aged women. This study analyzed 3D shape data of 401 females ranging in age from 40 to 59 years who participated in the 6th Size Korea project. Based on the Size Korea 3D measurement standard, 27 additional items such as height, protrusion, and angle were measured in the 3D scan data. Nine factors were extracted from the analysis of constituent factors of the torso: "vertical size of torso," "flatness and protrusion of abdomen," "torso front extrusion," "upper body height," "bust size and flatness," "size of belly and angle of lower abdomen," "hip length," "hip flatness," and "horizontal size of bust." As a result of the cluster analysis using these nine factors, the torsos of middle-aged women were classified into three types. Type 1 has upper abdominal deposition with a small and long upper body and an advanced abdomen; type 2 has lower abdominal deposition with a small and short torso and a small belly and hip flexion; and type 3 has central abdominal deposition with a big and long torso, large breasts, and protruding abdo¬men front. The middle-aged women were mostly distributed in Type 2. The above results will be useful as basic data for the development of clothing with improved fit to accommodate the changed physical characteristics of middle-aged women.

• Archives of Craniofacial Surgery
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• v.23 no.2
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• pp.64-70
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• 2022

Background: Anterolateral thigh (ALT) flaps are versatile soft tissue flaps that have become the standard soft-tissue flaps used for head and neck reconstruction. They provide a long vascular pedicle, constant vessel diameter, abundant soft tissue coverage, and minimal donor site morbidity. The ALT flap was initially designed on the basis of a septocutaneous (SC) perforator. However, more recent research has shown that a substantial number of ALT flaps are now based on musculocutaneous (MC) perforators, and the ratio between MC and SC perforators varies among studies. In this study, we analyzed the perforating pattern of ALT flaps along with their clinical outcomes during head and neck reconstruction in the Korean population. Methods: From October 2016 to July 2020, 68 patients who had undergone an ALT flap procedure for head and neck reconstruction were enrolled retrospectively. The perforating pattern of the cutaneous perforator vessel (MC perforator/SC perforator/oblique branch), pedicle length, and flap size were analyzed intraoperatively. Patient demographics and flap necrosis rates were also calculated. Results: The highest number of cutaneous perforator vessels supplying the ALT flap were the MC perforators (87%). The proportion of MC perforators was significantly higher than that of the SC perforators and oblique branches. Flap necrosis occurred in seven cases (11.86%); sex, hypertension, diabetes mellitus, coronary artery disease, perforator course, and history of radiotherapy did not significantly affect flap necrosis. Conclusion: The ALT free flap procedure remains popular for reconstruction of the head and neck. In this study, we observed that the majority of cutaneous vessels supplying the flaps were MC perforators (87%). When using the MC perforator during flap elevation, careful dissection of the perforator is required to achieve successful ALT flaps because intramuscular dissection is difficult. Perforator pattern and history of radiotherapy did not affect flap necrosis.

• Nuclear Engineering and Technology
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• v.54 no.4
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• pp.1421-1430
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• 2022

The computation of the solid angle and the detector efficiency is considering to be one of the most important factors during the measuring process for the radioactivity, especially the cylindrical γ-ray NaI(Tl) detectors nowadays have applications in several fields such as industry, hazardous for health, the gamma-ray radiation detectors grow to be the main essential instruments in radiation protection sector. In the present work, a generic numerical simulation method (NSM) for calculating the efficiency of the γ-ray spectrometry setup is established. The formulas are suitable for any type of source-to-detector shape and can be valuable to determine the full-energy peak and the total efficiencies and P/T ratio of cylindrical γ-ray NaI(Tl) detector setup concerning the truncated conical radioactive source. This methodology is based on estimate the path length of γ-ray radiation inside the detector active medium, inside the source itself, and the self-attenuation correction factors, which typically use to correct the sample attenuation of the original geometry source. The calculations can be completed in general by using extra reasonable and complicate analytical and numerical techniques than the standard models; especially the effective solid angle, and the detector efficiency have to be calculated in case of the truncated conical radioactive source studied condition. Moreover, the (NSM) can be used for the straight calculations of the γ-ray detector efficiency after the computation of improvement that need in the case of γ-γ coincidence summing (CS). The (NSM) confirmation of the development created by the efficiency transfer method has been achieved by comparing the results of the measuring truncated conical radioactive source with certified nuclide activities with the γ-ray NaI(Tl) detector, and a good agreement was obtained after corrections of (CS). The methodology can be unlimited to find the theoretical efficiencies and modifications equivalent to any geometry by essential sufficiently the physical selective considered situation.

• Structural Engineering and Mechanics
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• v.81 no.5
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• pp.565-574
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• 2022

The infrastructures such as offshore, bridges, power plant, oil and gas piping and aircraft operate in a harsh environment during their service life. Structural integrity of engineering components used in these industries is paramount for the reliability and economics of operation. Two regression models based on the concept of Gaussian process regression (GPR) and Minimax probability machine regression (MPMR) were developed to predict stress intensity factor range (𝚫K). Both GPR and MPMR are in the frame work of probability distribution. Models were developed by using the fatigue crack growth data in MATLAB by appropriately modifying the tools. Fatigue crack growth experiments were carried out on Eccentrically-loaded Single Edge notch Tension (ESE(T)) specimens made of API 5L X65 Grade steel in inert and corrosive environments (2.0% and 3.5% NaCl). The experiments were carried out under constant amplitude cyclic loading with a stress ratio of 0.1 and 5.0 Hz frequency (inert environment), 0.5 Hz frequency (corrosive environment). Crack growth rate (da/dN) and stress intensity factor range (𝚫K) values were evaluated at incremental values of loading cycle and crack length. About 70 to 75% of the data has been used for training and the remaining for validation of the models. It is observed that the predicted SIF range is in good agreement with the corresponding experimental observations. Further, the performance of the models was assessed with several statistical parameters, namely, Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Coefficient of Efficiency (E), Root Mean Square Error to Observation's Standard Deviation Ratio (RSR), Normalized Mean Bias Error (NMBE), Performance Index (ρ) and Variance Account Factor (VAF).

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.5
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• pp.791-799
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• 2022

Among excursion and ferry boats, small boats with a length of less than 12 m are exempted from the stability standard according to the ship safety act. The boarding capacity of these small excursion and ferry boats is calculated by the seating area according to the excursion ship and ferry business act. Many excursion and ferry boats have installed deck structures such as awnings after launching. Therefore, this study attempted to analyze the cause of the accident by estimating the stability based on the case of an actual ferry boat capsizing accident. The analysis results indicated that passengers stood up to disembark at the same time while the boarding capacity was exceeded. However, even if the ferry boat complied with the boarding capacity, a possibility of capsize existed if the passengers on one side of the boat stood up. Therefore, the following were suggested to improve the safety: calculating the boarding capacity using the stability test and recommending the maximum total weight for the boarding capacity.

• The Research Journal of the Costume Culture
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• v.30 no.4
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• pp.495-512
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• 2022

This study aims to design a new sizing system for hygienic masks to protect against COVID-19-related respiratory disorders. The product sizes were collected from 70 commercially available hygienic masks, and 18 head measurements were obtained from the three-dimensional (3D) scan data of 2,048 men and women aged 20 to 69 years from the 6th Size Korea Survey. The statistical analysis was performed using the IBM Statistical Package for the Social Sciences (SPSS) 28.0 program. The "bitragion-subnasale arc" and "menton-sellion length" were chosen as the key body dimensions for the hygienic mask sizing system. The linear regressions with 18 3D head measurements were analyzed, and it was determined that the key body dimensions were useful for statistically predicting other 3D head measurements related to hygienic masks. A new sizing system was proposed for two types of masks, "masks with a tight fit" and "masks with a loose fit," taking into account the existing Korean Industrial Standards (KS) and the shortcomings of the sizes of hygienic masks on the market. The sizing system for tight-fitting masks consisted of the key body dimensions, with their sizes indicated by a pair of numbers. The sizing system for loose-fitting masks consisted solely of the bitragion-subnasale arc, with their sizes denoted by letters such as S, M, and L (denoting small, medium, and large, respectively). Future studies should consider this mask sizing system for different age groups, such as children and adolescents.

• Journal of the Korean Wood Science and Technology
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• v.51 no.5
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• pp.334-344
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• 2023

Dregs from the sugar palm (Arenga pinnata) starch industry are considered a waste product of the agricultural industry and have not yet been optimally utilized. Therefore, this study aimed to manufacture particleboards from dregs using different amounts of adhesive and particle size ratios. Sugar palm dregs, which had been separated into fibers and powder/fine particles, were used as raw material for making particleboards. The fiber had an average length of 6.84 ± 3.23 cm, while the fine particles were of a size that passed through size 10 mesh and remained in size 60 mesh. Three ratios of fiber to fine particles (100:0, 75:25, and 50:50 wt%) with three different amounts of sucrose-citric acid adhesive (10, 15, and 20 wt%) were used in this study. Increasing the amount of fine particles and the resin content can improve the physical properties and the internal bond strength of boards made from sugar palm dregs. The fine particles possibly filled the gap between the fibers in the particleboard, while the fibers exhibited a high bending strength. As a result, a high-performance particleboard can be attained by combining the composition ratio of fiber/fine particles and resin content. In this study, particleboards made from fiber/fine particles (75:25 wt%) and adhesive content of 15 wt% and 20 wt% had the mechanical properties that met the requirements of Japanese Industrial Standard (JIS) A 5908 type 18. Sugar palm dregs have the potential to be used as raw materials to create value-added particleboards.

• Imaging Science in Dentistry
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• v.53 no.1
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• pp.43-51
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• 2023

Purpose: This study aimed to assess texture analysis(TA) of cone-beam computed tomography (CBCT) images as a quantitative tool for the differential diagnosis of odontogenic and non-odontogenic maxillary sinusitis(OS and NOS, respectively). Materials and Methods: CBCT images of 40 patients diagnosed with OS (N=20) and NOS (N=20) were evaluated. The gray level co-occurrence (GLCM) matrix parameters, and gray level run length matrix texture (GLRLM) parameters were extracted using manually placed regions of interest on lesion images. Seven texture parameters were calculated using GLCM and 4 parameters using GLRLM. The Mann-Whitney test was used for comparisons between the groups, and the Levene test was performed to confirm the homogeneity of variance (α=5%). Results: The results showed statistically significant differences(P<0.05) between the OS and NOS patients regarding 3 TA parameters. NOS patients presented higher values for contrast, while OS patients presented higher values for correlation and inverse difference moment. Greater textural homogeneity was observed in the OS patients than in the NOS patients, with statistically significant differences in standard deviations between the groups for correlation, sum of squares, sum of entropy, and entropy. Conclusion: TA enabled quantitative differentiation between OS and NOS on CBCT images by using the parameters of contrast, correlation, and inverse difference moment.