• Smart Structures and Systems
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• v.23 no.6
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• pp.653-667
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• 2019

Using cross-ties to connect cables together when forming a cable network is regarded as an efficient method of mitigating cable vibrations. Cross-ties have been extended and fixed on bridge decks or towers in some engineering applications. However, the dynamics of this kind of system need to be further studied, and the effects of extending cross-links to bridge decks/towers on the modal response of the system should be assessed in detail. In this paper, a system of two cables connected by an inter-supported cross-link with another lower cross-link extended to the ground is proposed and analyzed. The characteristic equation of the system is derived, and some limiting solutions in closed form of the system are derived. Roots of cable system with special configurations are also discussed, attention being given to the case when the two cables are identical. A predictable mode behavior was found when the stiffness of inter-connection cross-link and the cross-link extended to the ground were the same. The vector of mode energy distribution and the degree of mode localization index are proposed so as to distinguish global and local modes. The change of mode behaviors is further discussed in the case when the two cables are not identical. Effects of cross-link stiffness, cross-link location, mass-tension ratio, cable length ratio and frequency ratio on $1^{st}$ mode frequency and mode shape are addressed.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.377-384
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• 2018

The chamber method is widely used for measuring methane emission from paddy rice fields. The closed static chamber has advantages of easy installation and removal in the field and low manufacturing cost. However, the manual chamber method requires a lot of labor and has a limited sampling time and frequency. To overcome the disadvantages of the manual chamber, the auto-chamber system is used for measuring methane emission. We compared the differences in methane flux between the auto-chamber and manual chamber. To investigate methane emissions by the two methods, a chamber was installed for each of the following treatments : control without rice straw (NA), spring plowing after autumn rice straw application (SPRA) and autumn plowing after autumn rice straw application (APRA). The total methane emission was lowest in the control and highest in APRA with both methods. There was no significant difference in total methane emission between the methods, but dynamic fluctuation in methane with temperature change was accurately measured in the auto-chamber. Measuring methane emission with an auto-chamber system is expected to reduce uncertainty and increase accuracy, accompanied by labor reduction.

• Steel and Composite Structures
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• v.38 no.3
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• pp.337-353
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• 2021

Micro-electro-mechanical systems (MEMS) are widely employed in sensors, biomedical devices, optic sectors, and micro-accelerometers. New reinforcement materials such as carbon nanotubes as well as graphene platelets provide stiffer structures with controllable mechanical specifications by changing the graphene platelet features. This paper deals with buckling analyses of functionally graded graphene platelets micro plates with two piezoelectric layers subjected to external applied voltage. Governing equations are based on Kirchhoff plate theory assumptions beside the modified couple stress theory to incorporate the micro scale influences. A uniform temperature change and external electric field are regarded along the micro plate thickness. Moreover, an external in-plane mechanical load is uniformly distributed along the micro plate edges. The Hamilton's principle is employed to extract the governing equations. The material properties of each composite layer reinforced with graphene platelets of the considered micro plate are evaluated by the Halpin-Tsai micromechanical model. The governing equations are solved by the Navier's approach for the case of simply-supported boundary condition. The effects of the external applied voltage, the material length scale parameter, the thickness of the piezoelectric layers, the side, the length and the weight fraction of the graphene platelets as well as the graphene platelets distribution pattern on the critical buckling temperature change and on the critical buckling in-plane load are investigated. The outcomes illustrate the reduction of the thermal buckling strength independent of the graphene platelets distribution pattern while meanwhile the mechanical buckling strength is promoted. Furthermore, a negative voltage, -50 Volt, strengthens the micro plate stability against the thermal buckling occurrence about 9% while a positive voltage, 50 Volt, decreases the critical buckling load about 9% independent of the graphene platelet distribution pattern.

• Archives of Craniofacial Surgery
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• v.23 no.1
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• pp.29-33
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• 2022

Background: There have been many reports of nasal bone fractures in adults, but there are few clinical reports of them in adolescents, although adolescence is the main growth period of the nasal bone. In addition, previous studies have tended to classify and describe child and adolescent nasal fractures in the same category. The aim of this study was to identify the clinical aspects of nasal fractures in adolescents, and to evaluate the characteristics of nasal fractures in the growth period. Methods: Our institution's database was reviewed to extract data on adolescent patients between the age of 13 to 18 who had isolated nasal bone fractures from March 2012 to February 2020. The study excluded patients with other facial fractures, previous facial fractures, or congenital deformities. Results: This study included 243 boys and 26 girls. Interpersonal violence and sports-related accidents accounted for 85 and 79 cases, respectively. There were 128 frontal impact injuries and 132 lateral impact injuries, and 97 patients had accompanying septal fractures. An accompanying septal fracture was present in 36.06% of all patients, but in 51.20% of those who underwent surgery. Conclusion: The prevalence of adolescent nasal fractures was significantly higher in boys, to a greater extent than observed for pediatric or adult fractures. The main causes of fractures were interpersonal violence and sports-related accidents. An explanation for these results is that adolescent boys are more prone to have violent accidents or companionship with active sports than other age or sex groups, leading to substantially more fractures.

• Journal of International Area Studies (JIAS)
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• v.14 no.3
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• pp.57-80
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• 2010

This study aims at the evaluation of procedural changes and policy outcome caused by the Open Method of Coordination(OMC) on Social Inclusion in the European Union. The policy instruments of the OMC introduced by the Lisbon Council can be divided into two groups: the outcome-oriented New Public Management(NPM) and the process-oriented Directly Deliberative Polyarchy(DDP). By considering the adoption process of the NPM instruments, it can be said that OMC could not be effective due to the vagueness of its objectives, the institutional barriers in decentralized decision-making, and the rejection of benchmarking by the Member States. The intended learning by deliberation and peer review as indicated by the normative DDP, is hard to achieve because they are not so reflexive due to relatively restricted and closed participation. We also cannot find any significant reduction of poverty after the long implementation of the OMC. Considering the higher recognition of poverty problem and expanding NGOs concerned with it, however, we may see some significant impact in the future.

• Journal of Korean Foot and Ankle Society
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• v.8 no.1
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• pp.46-51
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• 2004

Purpose: Problematic late sequelae are common following a calcaneal fracture regardless of the initial treatment. We retrospectively evaluated the painful conditions and reviewed the results of the operative treatment in patients with previously treated calcaneal fractures. Materials and Methods: Between October 1996 and September 2001, forty-three patients who underwent subsequent surgical treatment for late sequelae of calcaneal fracture were reviewed. The initial treatment consisted of only immobilization in a cast in 7 patients, closed reduction with pin fixation (Essex-Lopresti technique) in 22 and open reduction and internal fixation in 14. Painful conditions in the hind foot included subtalar arthritis in 31 patients, calcaneofibular impingement in 13, peroneal tendinitis in 6, displaced posterior bony fragment in 3, sural neuritis in 2, subtalar and midtarsal arthritis in 1 and displaced plantar bony fragment in 1. The surgical procedures for the late complications were performed at a mean of 19 months (range, 6 to 35 months) after the injury and consisted of lateral wall ostectomy and in situ subtalar fusion in 28 patients, only lateral wall ostectomy in 5 patients, lateral wall ostectomy and subtalar distraction arthrodesis in 3, removal of displaced posterior bony fragment in 3, sural nerve transposition in the peroneus brevis in 2, triple arthrodesis in 1 and removal of displaced plantar bony fragment in 1. Mean postoperative follow up period was 57 months (range, 33 to 82 months). The results of treatment were evaluated on the basis of pain, improvement in the ability to perform activities of daily living, to return to work or to a pre-injury level of activity. Results: Pain was partially relieved in 38 patients (88%), but not relieved in 5. Function improved in 34 patients (79%), and 32 (74%) returned to work or to a pre-injury level of activity. There was a trend that the longer the interval between the injury and the operation, the longer the subsequent interval until the patient returned to full activities or work. Conclusion: Meticulous physical examination and intensive prompt treatment for remaining pain after initial treatment of calcaneal fractures are recommended for patient's satisfaction and returning to work.

• Journal of Veterinary Clinics
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• v.30 no.1
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• pp.49-52
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• 2013

A wild black-crowned night heron (Nycticorax nycticorax) with dehydration and a non-weight bearing lameness of the left leg was rescued. On physical examination, the left knee was displaced laterally at almost a $90^{\circ}$ angle with firm swelling and crepitus in the area of the coxofemoral joint. Radiographs confirmed cranio-dorsal coxofemoral luxation. A closed reduction attempt failed. The coxofemoral joint luxation was reduced surgically by placement of the femoral neck next to the pelvis with a suture. Ten days after surgery, radiographs and computed tomography showed the femoral neck and head were positioned well within the acetabulum. At 20 days, the bird was using the affected limb normally, and could hunt and forage for food in a rehabilitation housing unit with a small pond. The bird was successfully released into the wild. The placement of the femoral neck adjacent to the pelvis with a suture can be successfully performed for cases of avian coxofemoral joint luxation. Furthermore, this procedure can provide sufficient stabilization of the coxofemoral joint and acceptable limb function.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.302-311
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• 1992

Talus is a important structure of the ankle joint and its function is critical for ambulation and weight bearing. The talus fracture is rare, but the complications of fracture and dislocation are serious and resulting in avascular necrosis, osteoarthritis. So its treatment is carefully considered at initial status. Authors reviewed 11 cases of fracture and dislocation of the talus treated at Yeungnam university hospital from 1984 to 1991. The longest follow up was 8 years and shortest, 1 year. The results were as follows. 1. There were all males, the average age was 30 years old. 2. The most common cause was fall down(8 cases), and next traffic accident(2cases), sports injury(1 case). 3. According to Marti-Weber classification, 1 cases was type I, 1 in type II, 4 in type III and 5 in type IV. 4. The method of treatment were open reduction and internal fixation in 6 cases, the others were closed reduction in 5 cases. 5. Final results(by Hawkins grading system) were as follows, 3 cases were excellent, 4 cases were good, 1 case was fair and 3 cases were poor. 6. Complications were AVN in 2 cases, degenerative arthritis in 8 cases, malunion in 1 case. 7. The range of motion of the ankle joint was relatively preserved(74%), but in the subtalar joint it was decreased(43%).

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.293-305
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• 2009

Methane, as a greenhouse gas, is some 21~25 times more detrimental to the environmental than carbon dioxide. Landfills generally constitute the most important anthropogenic source, and methane emission from landfill was estimated as 35~73 Tg per year. Biological approaches using biocover (open system) and biofilter (closed system) can be a promising solution for older and/or smaller landfills where the methane production is too low for energy recovery or flaring and installation of a gas extraction system is inefficient. Methanotrophic bacteria, utilizing methane as a sole carbon and energy source, are responsible for the aerobic degradation (oxidation) of methane in the biological systems. Many bench-scale studies have demonstrated a high oxidation capacity in diverse filter bed materials such as soil, compost, earthworm cast and etc. Compost had been most often employed in the biological systems, and the methane oxidation rates in compost biocovers/boifilters ranged from 50 to $700\;g-CH_4\;m^{-2}\;d^{-1}$. Some preliminary field trials have showed the suitability of biocovers/biofilters for practical application and their satisfactory performance in mitigation methane emissions. Since the reduction of landfill methane emissions has been linked to carbon credits and trading schemes, the verified quantification of mitigated emissions through biocovers/biofilters is very important. Therefore, the assessment of in situ biocovers/biofilters performance should be standardized, and the reliable quantification methods of methane reduction is necessary.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.3 no.1
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• pp.26-31
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• 2010

Purpose: The purpose of this study is to evaluate the clinical usefulness of ultrasound in treatment of patella fracture. Material and Methods: Twenty cases of twenty patients with patella fracture radiographically from March, 2006 to September, 2009 were involved in this study, there were 8 males and 12 females, there were 13 right knees, 7 left knees, the average age was 43 years (range, 14~72 years). We decided the methods of treatment by using the ultrasound in conjunction with Drayer's test that examining the intactness of patella retinaculum. There were 10 transverse, 8 vertical and 2 comminuted fractures, we examined the patella retinaculum by using the ultrasound and performed Drayer's test. Results: In 12 cases of intact retinaculum, Drayer's test was negative and we allowed patients ambulation without surgical fixation especially. In 4 cases of completely ruptured retinaculum, Drayer's test was positive and we treated the patella fractures by the use of ORIF (open reduction and internal fixation) method, in 2 cases of partially ruptured retinaculum, Drayer's test was negative but displacement of fractures were more than 2 mm, we treated the patella fractures by the use of CRIF (closed reduction and internal fixation) method and obtained clinically satisfactory results. Conclusion: In conjunction with radiographs and Drayer's test, an ultrasound would be one of the useful diagnostic modality for determining treatment method of the patella fracture.