• The Journal of the Korean dental association
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• v.58 no.7
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• pp.404-411
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• 2020

This study reports the unusual complications of 22-year-old male who presented with sudden hearing loss after the right mandibular third molar extraction under local anesthesia with 3.6 ml of 2 % lidocaine. Total 8.75 mg of oral dexamethasone for 1 week immediately after extraction was prescribed in department of oral and maxillofacial surgery but hearing did not improve after 1 week. As referral to otolaryngology, total 600 mg of oral methylon and hyperbaric oxygen therapies were operated for 2 weeks. The hearing of patient was improved at 6 weeks after extraction but tinnitus was persisted even after 12 months. The reason and treatment were discussed with literature review, searching with the keywords ['hearing loss' AND ('dental' OR 'tooth extraction'OR'teeth extraction')] in PubMed and Google scholar at October 2019. Total five cases were reported after tooth extraction with local anesthesia. The sudden hearing loss could be associated with local anesthesia containing vasoconstrictors. Early steroid (extensive medication and intra-tympanic injection) and hyperbaric oxygen therapies were recommended within 2 weeks. As a proper treatment, hearing could be improved but other additional symptoms, such as tinnitus, dizziness, might be remained.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.5
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• pp.583-596
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• 2004

Statement of problem : Stress concentration on the neck bone affects the bone resorption, and finally the implant survival. Purpose: In order to examine the stress distribution on the neck bone and prosthesis abutment for implants, decreasing abutment sizes were used. Material and methods : Axisymmetric models were used to obtain the data required. These models were composed of 4mm implants with 3.4mm and 4mm abutments, 5mm implants with 3.4mm and 5mm abutments and 6mm implants with 3.4mm and 6mm abutments. All abutments were designed to received a 10mm high by 10mm diameter gold crown. Functional element analysis was used to obtain these results using data that consisted of 50 N vertical and 45 degree inclination forces. Results : 1. Changing the diameter of the abutment on the implant affects the effect of the inclination forces more than the effect of the vortical forces. 2. Changing the diameter of the abutment on the implant affect the effect of the inclination forces more than the effect of the vertical forces. 3. Experimentation showed that the larger diameter implants provided a decreased neck bone stress, whereas a larger diameter abutment provided a decrease marginal abutment stress. 4. Experimentation showed that the neck bone and abutment received more stress from inclination forces than vertical forces, Conclusions: By decreasing the size of the abutment on the implant we were able to diminishneck bone stress.

• Smart Structures and Systems
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• v.30 no.6
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• pp.661-671
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• 2022

Stayed cables are the key components for transmitting loads in cable-stayed bridges. Therefore, it is very important to evaluate the cable force condition to ensure bridge safety. An online condition assessment and anomaly localization method is proposed for cables based on the spatiotemporal correlation of grouped cable forces. First, an anomaly sensitive feature index is obtained based on the distribution characteristics of grouped cable forces. Second, an adaptive anomaly detection method based on the k-nearest neighbor rule is used to perform dissimilarity measurements on the extracted feature index, and such a method can effectively remove the interference of environment factors and vehicle loads on online condition assessment of the grouped cable forces. Furthermore, an online anomaly isolation and localization method for stay cables is established, and the complete decomposition contributions method is used to decompose the feature matrix of the grouped cable forces and build an anomaly isolation index. Finally, case studies were carried out to validate the proposed method using an in-service cable-stayed bridge equipped with a structural health monitoring system. The results show that the proposed approach is sensitive to the abnormal distribution of grouped cable forces and is robust to the influence of interference factors. In addition, the proposed approach can also localize the cables with abnormal cable forces online, which can be successfully applied to the field monitoring of cables for cable-stayed bridges.

• The Korean Nurse
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• v.20 no.1 s.109
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• pp.56-65
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• 1981

The purpose of this study is to indentify the degree of hospitalization anxiety is experiened by hospitalized patients in the Armed Forces General Hospital and to provide effective care to hospitalized patients for decresing their anxiety. The subjects in

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1993.04a
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• pp.101-108
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• 1993

A simplified dynamic analysis method for high-rise building structures is proposed in this study. In the proposed method, member forces are obtained through static analysis using story forces derived from story shear forces which are obtained using dynamic analysis procedure. Major advantage of the proposed method is in the convenience in load combinations for design analysis.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.431-433
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• 2007

The drawbeads, which is used for controlling the flow of the sheet by imposing the tension and for preventing the springback in the sheet metal forming process, affects a lot the formability because of the differences in the restraint and opening forces according to the drawbead shapes and dimensions. In this study, the experimental device enabling to measure the drawbead restraining and opening forces was manufactured and the drawing forces of circular, square, and step drawbeads are measured. The drawbead restraining and opening forces of a circular drawbead are increased as its drawbead height is increased. Similarly, those of a square drawbead are increased as its height is increased and shoulder radii decreased. Also, those of a step drawbead are increased as its height and difference in their heights are increased.

• Journal of Ship and Ocean Technology
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• v.3 no.2
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• pp.17-26
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• 1999

An experimental investigation on hydrodynamic forces acting on a porpoising craft at high advanced speeds up to Froude numbers Fn=6.0(Fn=U\ulcorner:Lo\ulcorner denote overall length of ship) in calm water is performed. Captive model tests and forced motion tests are carried out to measure the hydrodynamic forces. The results show that significant nonlinear effects for motion amplitudes appear in the restoring, the added mass and the damping coefficients. The experimental results are compared with the results of a prediction method of the hydrodynamic forces include the nonlinear effects, and show a good agreement with them. A simulation using the predicted hydrodynamic forces in a nonlinear motion equation is carried out to obtain the porpoising motion of a craft in calm water. The calculated results are in fairly good agreement with experimental ones.

• Tribology and Lubricants
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• v.22 no.6
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• pp.342-349
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• 2006

In this study, a dynamic behavior of rotor-bearing system used in CNG compressor has been investigated using the combined methodologies of finite elements and transfer matrices. The finite element is formulated including the field element for a shaft section and the point element for roller bearings. The Houbolt method is used to consider the time march for the integration of the system equations. The transient whirl response of rotating shaft supported on roller bearings is obtained, considering compression forces and unbalance forces at eccentric crank-pin part. And, the steady state displacements of the rotor are compared with a variation in stiffness coefficient of roller bearings. Results show that the loci of crankshaft considering unbalance forces and external compression forces are more severe in whirl motion than with only unbalance forces.

• Wind and Structures
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• v.4 no.5
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• pp.399-412
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• 2001

Simultaneous pressure and force measurements have been conducted on a stationary box deck section model for two configurations (namely without and with New Jersey traffic barriers) at various angles of incidence. The mean and fluctuating aerodynamic coefficients and pressure coefficients were derived, together with their spectra and with the coherence functions between the pressures and the total aerodynamic forces. The mean aerodynamic coefficients derived from force measurements are first compared with those derived from the integration of the pressures on the deck surface. Correlation between forces and local pressures are determined in order to gain insight on the wind excitation mechanism. The influence of the angle of incidence on the pressure distribution and on the fluctuating forces is also analysed. It is evidenced how particular deck section areas are more responsible for the aerodynamic excitation of the deck.

• Journal of KSNVE
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• v.10 no.3
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• pp.500-507
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• 2000

Dynamic forces due to mechanical and hydraulic related causes are always exerted on operating turbomachinery such as centrifugal pumps. To ensure the safety and the reliability of the pump. the magnitudes of the vibration must be kept within an acceptable limit. The focus of this paper is on the identification of the vibration behavior and the quantitative analysis of the hydraulic excitation forces. As the structure becomes more complex finite element analysis is essential to accurately predict the vibration characteristics and the excitation forces, This paper presents an experimental and analytical technique to find and solve to vibration problems in double volute double suction centrifugal pump. Measured vibration data due to the dynamic forces are presented and individual causes are identified, finally excitation forces of the pump are inversely estimated at each frequency on operating conditions.