• Earthquakes and Structures
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• v.22 no.4
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• pp.345-353
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• 2022

The configuration of an open ground floor (pilotis) is a common and very critical irregularity observed in multistory reinforced concrete frame structures. The characteristics and the geometrical formation of the beams of the first story proved to be a critical parameter for the overall seismic behavior of this type of Reinforced Concrete (RC) structures. In this work the combination of open ground floor (pilotis) morphology with very strong perimetrical beams at the level of the first story is studied. The observation of the seismic damages and the in situ measurements of the fundamental period of four buildings with this morphology and Π-shaped plan view are presented herein. Further analytical results of a pilotis type Π-shaped RC structure are also included in the study. From the measurements and the analytical results yield that the open ground floor configuration greatly influences the fundamental period whereas this morphology in combination with strong beams can lead to severe local shear damages in the columns of the ground floor. The structural damage was limited in the columns of the ground floor and yet based on the changes of the in situ measured fundamental period the damaged level is assessed as DI=88%. Furthermore, due to the Π-shape of the plan view the tendency of the parts of the building to move independently strongly influences the distribution of the damages over the ground floor vertical elements.

• Journal of the Korean Orthopaedic Association
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• v.55 no.4
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• pp.338-342
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• 2020

Periosteal chondroma is a rare, slow-growing, benign cartilaginous tumor that develops between the periosteum and cortex, but there are no reports of multiple periosteal chondroma of the toes. A 19-year-old male presented with a palpable mass of the right fourth toe with tenderness for one year. A radiology examination revealed multiple, radio-lucent lesions with mild cortical irregularity. The magnetic resonance imaging findings were chondrogenic tumors with multiple, well-defined T1-low and T2-high signal enhanced lesions involved in the fourth proximal, middle, and distal phalanges. The tumors were removed by a surgical resection and curettage. Histologically, the tumors were proven to be periosteal chondroma.

• Journal of Distribution Science
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• v.20 no.9
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• pp.127-139
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• 2022

Purpose: As sharing economy is becoming increasingly relevant to people's lives, we want to understand why people participate in the sharing economy. We propose and validate three factors that are likely to influence consumers' choice of participating in the sharing economy at distribution market. Also, we found antecedents that affect these variables. These antecedents include appointment and return convenient, extended operating time, variety-seeking need, usage irregularity, other's clean usage, and feeling of membership between users. Research design, data, and methodology: This research collected 341 questionnaire data from participants in China. These participants were asked about the usage of DiDi, the most popular shareware in China. The data analysis and hypothesis testing were conducted using SPSS and Amos. Results: Usage convenience, usefulness of short-term usage, and trust in other users were found to have a positive impact on consumers' intention to participate in the sharing economy. In addition, we found that all the antecedents affect these variables positively. Conclusions: This research provides new driving factors for consumer participation in the sharing economy. Moreover, these findings will help managers develop marketing strategies for inducing the consumers to participate in the sharing economy.

• Structural Engineering and Mechanics
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• v.87 no.5
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• pp.405-418
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• 2023

This study focused on the effectiveness of seismic isolation technique in case of a reinforced concrete structure with soft story defined as the stiffness irregularity between adjacent stories. In this context, a seismically isolated 3-story reinforced concrete structure was analyzed by gradually increasing the first story height (3.0, 4.5, and 6.0 m). The seismic isolation system of the structure is assumed to be composed of lead rubber bearings (LRB). In the analyses, isolators were modeled by both deteriorating (temperature-dependent analyses) and non-deteriorating (bounding analyses) hysteretic representations. The deterioration in strength of isolator is due to temperature rise in the lead core during cyclic motion. The ground motion pairs used in bi-directional nonlinear dynamic analyses were selected and scaled according to codified procedures. In the analyses, different isolation periods (Tiso) and characteristic strength to weight ratios (Q/W) were considered in order to determine the sensitivity of structural response to the isolator properties. Response quantities under consideration are floor accelerations, and interstory drift ratios. Analyses results are compared for both hysteretic representations of LRBs. Results are also used to assess the significance of the ratio between the horizontal stiffnesses of soft story and isolation system. It is revealed that seismic isolation is a viable method to reduce structural damage in structures with soft story.

• The Research Journal of the Costume Culture
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• v.31 no.1
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• pp.18-33
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• 2023

Zero-waste pattern cutting is a groundbreaking sustainable fashion practice. However, few brands and designers have pursued this method because it requires creative pattern design that diverges from the existing process of using pattern slopers. Therefore, application within the fashion industry is not sufficient. Therefore, in an attempt to highlight the key characteristics of zero-waste pattern design, this study classifies and analyzes cases in which similar designs employ zero-waste pattern-cutting techniques. We hope to make zero-waste pattern design more accessible by presenting realistic pattern-cutting guidelines. To this end, theoretical research on relevant literature, previous research, and online resources and an empirical analysis of cases involving zero-waste pattern cutting were conducted in parallel. As a result of the study, we were able to classify the factors of zero-waste pattern design in terms of fabric use, design, and composition. Regarding materials, our research revealed the importance of appropriate fabric width, understanding the difference between waste minimization and minimal fabric use, and easy reuse and recycling. In terms of design, the simultaneous progress of pattern and design work, adjustable loose silhouettes, and the use of surplus fabric for functional and decorative details emerged as key characteristics. For composition, we found that size adjustment limits, arrangement irregularity, and pattern shapes were crucial elements and that various arrangements revealed unlimited design potential.

• Earthquakes and Structures
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• v.26 no.6
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• pp.433-447
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• 2024

During earthquakes, regular buildings perform better than irregular buildings. In general, seismic design codes define a regular building using estimates of Storey Stiffness and Storey Strength. At present, seismic design codes do not recommend a specific method to estimate these parameters. Consequently, any method described in the literature can be applied to estimate the aforementioned parameters. Nevertheless, research has demonstrated that storey stiffness and storey strength vary depending on the estimation method employed. As a result, the same building can be regular or irregular, depending on the method employed to estimate storey stiffness and storey strength. Hence, there is a need to identify the best method to estimate storey stiffness and storey strength. For this purpose, the study presents a qualitative and quantitative evaluation of nine approaches used to determine storey stiffness. Similarly, the study compares six approaches for estimating storey strength. Subsequently, the study identifies the best method to estimate storey stiffness and storey strength using results of 350 linear time history analyses and 245 nonlinear time history analyses, respectively. Based on the comparison, it is concluded that the Fundamental Lateral Translational Mode Shape Method and Isolated Storey Method - A Particular Case are the best methods to estimate storey stiffness and storey strength of low-to-mid rise buildings, respectively.

• Journal of the Mineralogical Society of Korea
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• v.27 no.2
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• pp.85-95
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• 2014

The felsitic intrusives of Bulguksa granitic rocks of late Cretaceous in age are located at Mt. Daeduk, Daegu, where two different types of tourmalines are found. Two tourmalines show rounded and radiating in morphology and are found in separated region, but in same felsitic rocks. In this study, we investigate the chemical differences between two types of tourmaline and the effect of growing condition of the crystal on the its morphology. The rounded tourmaline has more amounts of Al and vacancy and less amounts of Ca, Na, K, Fe, Mn, Mg, which commonly occupy X and Y-site of the tourmaline. On the basis of the Diffusion-limited aggregation model, morphological irregularity indicates the active mobility of the magma. The radiating tourmaline, therefore, crystallized with active magma condition relatively, and the rounded tourmaline crystallized with stable magma condition created by decreasing temperature and the concentration of felsic components as the magma differentiate continually.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3502-3507
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• 2013

If a sky-bridge is rigidly connected to adjacent buildings, the irregularity of the connected structures is increased resulting in providing a worse seismic behavior. Therefore, a friction pendulum system (FPS) or lead rubber bearing (LRB) is frequently used for the connection system between a sky-bridge and building structures. These connection systems should be carefully designed to prevent a skyfall of a sky-bridge subjected to severe seismic loads. In this paper, the inevitable structural design procedures for a sky-bridge connection system using a friction pendulum system without uplift resistance capacity have been investigated. To this end, Nuri Dream Square building structure is used as a example structure. The structural design process of a friction pendulum system for fail safe of a sky-bridge has been proposed in this paper by evaluating structural responses of the sky-bridge and building structures subjected to earthquake loads.

• Journal of dental hygiene science
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• v.11 no.4
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• pp.375-380
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• 2011

This study evaluated whether fluoride treatment can affect recovery of the irregularity of enamel surface after tooth whitening with a high concentration of hydrogen peroxide (HP) activated by plasma arc light. A total of 36 bovine teeth stained with coke were used in this experiment. The specimens were classified into following three groups (two different commercial plasma arc groups and a control group without light curing source): (1) 35% HP gel only, (2): 35% HP gel and Plasma arc A, and (3) 35% HP gel and Plasma arc B. To measure color changes and surface morphologies before and after the bleaching, colorimeter and scanning electron microscopy were used, respectively. When the specimens were bleached with hydrogen peroxide and plasma arc lights, the bleaching effect was greater than when only hydrogen peroxide gels were used (Kruskal-Wallis test, p<0.05). In addition, plasma arc B showed the more color changes than plasma arc A (Bonferroni post-hoc test, p<0.05). The surfaces of the teeth treated with fluoride gel after the whitening treatment came to be smooth. Therefore, the results of this study suggested that the fluoride application for patients who got tooth whitening therapy with a high concentration of hydrogen peroxide gels activated by plasma arc light will be effective to recover rough enamel surfaces.

• Archives of Craniofacial Surgery
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• v.10 no.2
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• pp.91-96
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• 2009

Purpose: Frontal sinus fractures are relatively less common than other facial bone fractures. They are commonly concomitant with other facial bone fractures. They can cause severe complications but the optimal treatment of frontal sinus fractures remains controversial. Currently, many principles of treatment were introduced variously. The authors present valid and simplified protocols of treatment for frontal sinus fractures based on fracture pattern, nasofrontal duct injury, and complications. Methods: A retrospective chart review was performed on 36 cases of frontal sinus fractures between January, 2004 and January, 2009. The average age of patients was 33.7 years. Fracture patterns were classified by displacement of anterior and posterior wall, comminution, nasofrontal duct injury. These fractures were classified in 4 groups: I. anterior wall linear fractures; II. anterior wall displaced fractures; III. anterior wall displaced and posterior wall linear fractures; IV. anterior wall and posterior wall displaced fractures. Also, assessment of nasofrontal duct injury was conducted with preoperative coronal section computed tomographic scan and intraoperative findings. Patients were treated with various procedures including open reduction and internal fixation, obliteration, galeal frontalis flap and cranialization. Results: 12 patients are group I (33.3 percent), 14 patient were group II (38.8 percent), group III, IV were 5 each (13.9 percent). Frontal sinus fractures were commonly associated with zygomatic fractures (21.8 percent). 9 patients had nasofrontal duct injury. The complication rate was 25 percent (9 patients), including hypoesthesia, slight forehead irregularity, transient cerebrospinal fluid leakage. Conclusion: The critical element of successful frontal sinus fracture repair is precise diagnosis of the fracture pattern and nasofrontal duct injury. The main goal of management is the restoration of the sinus function and aesthetic preservation.