• Geomechanics and Engineering
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• v.30 no.6
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• pp.517-524
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• 2022

Every year, millions of waste tires are discarded across the world. Storage of waste tires presents many problems such as fire threats, epidemics, and non-economic factors. Furthermore, the disintegration process of waste tires is not economical or practical due to its time-consuming, and disposal requirements. In this study, half-section waste tires (HSWTs) were integrated with high-density polyethylene (HDPE) pipes under different relative density conditions. The main aim of the study was to reduce the deformation values of embedded HDPE pipes in sandy soil and to evaluate the soil-pipe interaction. In comprehensive laboratory tests, half-section waste tires were integrated in two different ways: in the middle of the pipeline and along the pipeline. Accordingly, it was concluded that the effectiveness of waste tires reduces the deformation and bending moment values in the critical regions of pipes. As a result of reinforcement in the mid-point of the pipe defined as the most critical region, 52% and 36% less deformation was observed in the crown and springlines of the pipe, respectively. In addition, the bending moment values for the same critical section were determined to be 40% less in the crown and 28% less in the springline regions of the pipe.

• Journal of the Korean Society of Visualization
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• v.21 no.1
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• pp.67-73
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• 2023

In the study, pool boing critical heat flux (CHF) was experimentally investigated depending on the length of heaters. A smooth silicon oxide surfaces are used as the boiling surfaces. As the results of pool boiling experiments based on distilled water in ambient pressure condition, the CHF decreased as the length of the heater increased. By the high speed imaging, it was shown that the number of vapor columns increased as the length of the heater increased. Comparing the number of vapor columns and the CHF according to the heater length, the change in the CHF according to the heater length was analyzed based on the hydrodynamic instability.

• Safety and Health at Work
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• v.14 no.1
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• pp.1-9
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• 2023

Background: Firefighting involves exposure of firefighters to risks related to this activity, serious injuries, and occupational diseases are recorded. There are other consequences such as thermal and emotional stress. This systematic review is proposed in order to analyze the risks and consequences faced by these workers and thus provide elements to improve safety management systems in institutions. Method: A descriptive observational study of systematic literature review on the risks and consequences of exposure to firefighters' activity was proposed, and the information was analyzed and described based on the available data and according to the variables determined. Results: The studies showed data on mechanical, physical, chemical, psychosocial risks, workers' perception and resilience, and epidemiological data. Information related to firefighters' activity on falls and slips, exposure to noise, and high concentrations of carbon monoxide is detailed. In addition, the relationship between burnout, cognitive, and physical fatigue as adverse effects on health and performance is mentioned. Conclusions: Among the preventive measures, the use of personal protective equipment is suggested, incorporation in prevention programs of information on exposure to risk factors, as well as the implementation of models that can predict the perception of workers, additionally, the generation of management systems with safety climate models for fire departments.

• Advances in concrete construction
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• v.16 no.1
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• pp.1-20
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• 2023

This study presents the experimental results performed to evaluate the effects of Polyvinyl-alcohol (PVA) and Polypropylene (PP) fibers on the fresh and residual mechanical properties of the hybrid fiber reinforced SCC before and after the exposure of 250℃, 500℃ and 750℃ temperatures. The compressive and splitting tensile strength, modulus of rupture (MOR), ultrasonic pulse velocity (UPV) as well as toughness and weight loss were investigated at different temperatures. PVA and PP fibers were added into SCC mixtures having only macro steel fiber and also having binary hybridization of both macro and micro steel fiber. The results showed that the use of micro steel fiber replaced by macro steel fiber improved the fresh and hardened properties compared to the use of only macro steel fiber. Moreover, it was emphasized that PVA or PP enhanced the residual flexural performance of SCC, generally, while it negatively influenced the workability, weight loss, UPV and the residual strengths with regards to the use of single steel fiber and binary steel fiber hybridization. Compared to the effect of synthetic fibers, PP had slightly more positive effect in the view of workability while PVA enhanced the residual mechanical properties more.

• Steel and Composite Structures
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• v.50 no.4
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• pp.375-382
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• 2024

The network theory studies interconnection between discrete objects to find about the behavior of a collection of objects. Also, nanomaterials are a collection of discrete atoms interconnected together to perform a specific task of mechanical or/and electrical type. Therefore, it is reasonable to use the network theory in the study of behavior of super-molecule in nano-scale. In the current study, we aim to examine vibrational behavior of spherical nanostructured composite with different geometrical and materials properties. In this regard, a specific shear deformation displacement theory, classical elasticity theory and analytical solution to find the natural frequency of the spherical nano-composite structure. The analytical results are validated by comparison to finite element (FE). Further, a detail comprehensive results of frequency variations are presented in terms of different parameters. It is revealed that the current methodology provides accurate results in comparison to FE results. On the other hand, different geometrical and weight fraction have influential role in determining frequency of the structure.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.5
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• pp.211-217
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• 2006

This analysis evaluated small and large temperature gradient effects on the FRP deck considering lightweight of FRP deck and ply orientations at the interface between steel girders and FRP deck. Finally, the analytical results shows the possible failure mechanism of FRP deck under various temperature changes and its corresponding index is suddenly varied depending on the rapid change of temperature on the deck plate.

• Journal of Pharmacopuncture
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• v.27 no.3
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• pp.264-269
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• 2024

Background: Conventional treatments for seborrheic dermatitis often lead to a recurring cycle of symptom improvement and worsening, resulting in chronic conditions. Thus, safer and more effective alternatives are needed. In Korean medicine, Hwangryunhaedok-tang tablets, targeted at treating the fire-heat syndrome, offer a more fundamental approach to manage seborrheic dermatitis. Clinical Features and Outcomes: In this study, we monitored the changes in the symptoms of two patients with seborrheic dermatitis who were treated with Hwangryunhaedoktang tablets. The patients were administered this medication during the treatment period. The effectiveness of the treatment was assessed by visually recording changes in the affected skin areas using photographs and evaluating symptoms such as heat, itching, and stinging in these areas using a visual analog scale (VAS). Visible improvements in the patients' skin conditions were observed after taking Hwangryunhaedok-tang tablets. Following treatment, VAS scores for subjective symptoms such as heat sensation, itching, and stinging in the affected areas decreased. Conclusion: This study offers evidence of a potential alternative approach for treating seborrheic dermatitis using Kyungbang Hwangryunhaedok-tang tablets. However, it highlights the necessity for further research on the appropriate dosage, side effects, and long-term effectiveness of this treatment.

• Herbal Formula Science
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• v.16 no.1
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• pp.1-13
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• 2008

The Oriental Medical Literature Relating to Treatment of Gyogamdan in Ki Stagnation : focused on Suseunghwagang The normal drift of a current Ki can maintain a function of body. An abnormal drift of a current Ki which is called a Ki Stagnation by lots of thinking or agony gets to a various disease syndrome. A Ki Stagnation is similar to a mental stress disease. It is a common disease for us to contact easily, so, it is very valuable to study. Gyogamdan which is composed of Cyperi Rhizoma L. and Poria cum Radix pini has been used by basic prescription of a symptom related to all kinds of Ki disease, after being recorded to Hongssijibhumbang first. Gyogamdan has an ability to regulate Ki , through 'Suseunghwagang-centric'(Ascending the Water and Descending the Fire) in body. Gyogamdan compares to Gamijajoohwan which can treat eyes dizzy by ascending heat and Gongjindan which can regulate lack of basic Ki through 'Suseunghwagang-centric'. It is general for the herb and acupuncture to give medical treatment coming together in oriental medicine, so do Gyogamdan and Sagwan Acupoints. Gyogamdan in composition Cyperi Rhizoma L. and Poria cum Radix pini and Sagwan Acupoints in composition Hapkok and T'aech'ung get to synergistic effects. Therefore, a Ki Stagnation treatment through unions of Gyogamdan and Sagwan Acupoints may have more effects than when a treatment used each one alone. Be considered that we have to study Gyogamdan and Sagwan Acupoints carried out an experiment to set up the previous theory in future

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1351-1356
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• 2012

The objective of this study was to compare body weight, ADG, and feed:gain ratio of antibiotic-free pigs from Yorkshire dams and sired by Yorkshire (YY), Berkshire (BY), Large Black (LBY) or Tamworth (TY) boars. All the crossbred pigs in each of three trials were raised as one group from weaning to finishing in the same deep-bedded hoop, providing a comfortable environment for the animals which allowed rooting and other natural behaviors. Birth, weaning and litter weights were measured and recorded. From approximately 50 kg to market weight (125 kg), feed intake and body weights were recorded manually (body weight) or using a FIRE (Feed Intake Recording Equipment, Osborne Industries Inc. Osborne, Kansas) system with eight individual feeding stations. Feed intake data for 106 finishing pigs between 140 and 210 d of age and the resulting weights and feed conversion ratios were analyzed by breed type. Least square means for body weights (birth, weaning and to 240 d) were estimated with Proc Mixed in SAS 9.2 for fixed effects such as crossbreed and days of age within the sire breed. The differences within fixed effects were compared using least significant differences with DIFF option. Individual birth weights and weaning weights were influenced by sire breed (p<0.05). For birth weight, BY pigs were the lightest, TY and YY pigs were the heaviest but similar to each other and LBY pigs were intermediate. For weaning weights, BY and LBY pigs were heavier than TY and YY pigs. However, litter birth and weaning weights were not influenced by sire breed, and average daily gain was also not significantly different among breed types. Tamworth sired pigs had lower overall body weight gain, and feed conversion was lower in TY and YY groups than BY and LBY groups (p<0.05), however, number of observations was somewhat limited for feed conversion and for Tamworth pigs. Overall, no convincing differences among breed types were noted for this study, but growth performance in the outdoor environment was satisfactory.

• Journal of Industrial Convergence
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• v.18 no.3
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• pp.117-124
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• 2020

In addition to education, the effects of color on humans have been studied in various areas such as human emotions, behaviors, and relationships between bodies. This study is based on the assumption that the color expression of University students can be observed to understand the inner and inclinations of University students, and that color expression activities can be a means of psychological expression, self-expression, and emotional relief. This study is aimed to find how much the color mind expression program effects the psychological mind state of University students. As a result of the study, the color mind expression program influenced the expression of inner feelings and emotions of University students, and had a positive effect on color psychology and utilization. In addition, overall, the color mind expression program was effective in positive and psychological recovery of negative emotions, such as being able to honestly express the difficulties felt in the process of preparing for employment.