• Membrane and Water Treatment
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• v.7 no.4
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• pp.341-353
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• 2016

Papermaking reconstituted tobacco is an important strategy for recycling the waste tobacco residues. To indentify the influences of the inorganic components on harmful components delivery in cigarette smoke, a self-made electrodialysis stack was assembled to desalt the tobacco extract. The influences of the applied current and extract content on the removal rate of the inorganic ions were investigated. Results indicated that the applied current was a dominant impact on the desalination performance. High currents lower than the limiting current density could accelerate the desalting efficiency but cause higher energy consumption. A current of 2 A, or current density of ${\sim}11mA{\cdot}cm^{-2}$, was an optimal choice by considering both the energy consumption and desalting efficiency. A 20% tobacco extract was an appropriate content for the electrodialysis process. More than 90% of inorganic ions could be removed under the optimum condition. The preliminary result indicated that removal of inorganic components was beneficial to decrease the harmful component delivery in cigarette smoke. Naturally, ED is an environmentally friendly and high-effective technology for desalting the tobacco extract.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.16 no.1
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• pp.85-87
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• 2005

The pyriform sinus fistula can cause a recurrent abscess in the neck and the current treatment of choice involves complete excision of the sinus tract. But, because of excisional difficult, chemical cautery has been intermittently used as a successful substitute. Recently we experienced a case of pyriform sinus fistula of 9 year-old female who was successfully treated with chemocauterization with trichloroacetic acid(TCA) and ligation of the internal opening of the fistula tract on suspension laryngoscopy. So we report this rate case with review of literatures.

• Korean Journal of Head & Neck Oncology
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• v.17 no.2
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• pp.234-237
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• 2001

Pyriform sinus fistula is a rare anomaly arising from 3rd or 4th branchial apparatus and has been recognized as one cause of acute suppurative thyroiditis or acute deep neck infection. Pyriform sinus fistula must be considered when a clinician is encountered recurrent left lower neck abscess and a history of repeated incision and drainage. The confirmation of the diagnosis is made when the fistula tract is identified on a barium swallow study and when the internal orifice of the fistula is found at the apex of pyriform sinus on laryngoscopic examination. A complete excision of the fistula tract has been proposed as a treatment of choice. However, in some cases it is very difficult to resect the tract completely because of severe inflammation and repeated drainage procedure. We present three cases of pyriform sinus fistula which are successfully treated by laryngomicroscopic chemocauterization using synthetic fibrin and $AgNO_3$.

• Journal of Yeungnam Medical Science
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• v.28 no.2
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• pp.173-179
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• 2011

Polymyositis is diffuse, inflammatory myopathy with proximal-muscle weakness due to lymphocyte infiltration to the muscle layer. The exact cause of the muscle weakness is unclear but may be related with an immunologic mechanism. Using high-dose steroid is the treatment of choice for polymyositis. It is difficult to distinguish steroid-resistant polymyositis from steroid myopathy, however, in the course of high-dose steroid therapy. These authors encountered a steroid myopathy patient during polymyositis treatment with high-dose steroid. A 57-year-old woman was diagnosed with polymyositis and was treated with high-dose steroid. Her condition was initially improved, but in the course of the treatment, her symptom was aggravated without increasing the muscle enzymes. Her muscle weakness was improved by reducing the steroid dosage.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.558-561
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• 1994

Bronchopulmonary endometriosis is a rare cause of hemoptysis. We describe a woman with recurrent hemoptysis during menstruation. The site of origin of hemoptysis was localized on chest CT images. CT appears to be the method of choice for the correct intrapulmonary localization of this disease. The hematogenous spread from the pelvis to the lungs has been proposed for the mechanism for the development of parenchymal pulmonary endometriosis. Thoracic endometriosis is reviewed and new therapeutic modalities are discussed.

• Earthquakes and Structures
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• v.15 no.4
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• pp.403-410
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• 2018

The choice of attenuation relationships is one of the most important parts of seismic hazard analysis as using a different attenuation relationship will cause significant differences in the final result, particularly in near distances. This problem is responsible for huge sensibilities of attenuation relationships which are used in seismic hazard analysis. For achieving this goal, attenuation relationships require a good compatibility with the target region. Many researchers have put substantial efforts in their studies of strong ground motion predictions, and each of them had an influence on the progress of attenuation relationships. In this study, two attenuation relationships are presented using seismic data of Mazandaran province in the north of Iran by Genetic Expression Programming (GEP) algorithm. Two site classifications of soil and rock were considered regarding the shear wave velocity of top 30 meters of site. The quantity of primary data was 93 records; 63 of them were recorded on rock and 30 of them recorded on soil. Due to the shortage of records, a regression technique had been used for increasing them. Through using this technique, 693 data had been created; 178 data for soil and 515 data for rock conditions. The Results of this study show the observed PGA values in the region have high correlation coefficients with the predicted values and can be used in seismic hazard analysis studies in the region.

• Smart Structures and Systems
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• v.16 no.4
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• pp.725-742
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• 2015

Tuned mass dampers (TMD) are devices employed in vibration control since the beginning of the twentieth century. However, their implementation for controlling the seismic response in civil structures is more recent. While the efficiency of TMD on structures under far-field earthquakes has been demonstrated, the convenience of its employment against near-fault earthquakes is still under discussion. In this context, the study of this type of device is raised, not as an alternative to the seismic isolation, which is clearly a better choice for new buildings, but rather as an improvement in the structural safety of existing buildings. Seismic records with an impulsive character have been registered in the vicinity of faults that cause seismic events. In this paper, the ability of TMD to control the response of structures that experience inelastic deformations and eventually reach collapse subject to the action of such earthquakes is studied. The results of a series of nonlinear dynamic analyses are presented. These analyses are performed on a numerical model of a structure under the action of near-fault earthquakes. The structure analyzed in this study is a steel frame which behaves as a single degree of freedom (SDOF) system. TMD with different mass values are added on the numerical model of the structure, and the TMD performance is evaluated by comparing the response of the structure with and without the control device.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.10
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• pp.1023-1030
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• 2015

The purpose of this paper is to present the basic mathematical modeling of a hexacopter, which could be used to develop proper methods for stabilization and trajectory control. A hexacopter consists of six rotors with three pairs of counter-rotating fixed-pitch blades. This mechanism is an under-actuated, dynamically unstable, six-degrees-of-freedom system. The whole motion of this object consists of translational and rotational motion in three dimensions, where the translational motion is created by changing the direction and magnitude of the upward propeller thrust. The hexacopter is controlled by adjusting the angular velocities of the rotors, which are spun by electric motors. It is assumed to be a rigid body; thus, the differential equation of the hexacopter dynamics can be derived from the Newton-Euler equation. The Euler-angle parametrization of the three-dimensional rotations contains singular points in the coordinate space that can cause failure of both the dynamical model and control. In order to avoid singularities, the rotations of the hexacopter are parametrized in terms of quaternions. This choice has been made considering the linearity of the quaternion formulation and their stability and efficiency. Further, control simulation of a hexacopter applying cascaded-PID control is also presented in this paper.

• Journal of Chest Surgery
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• v.8 no.2
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• pp.125-134
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• 1975

The record of 137 patients with spontaneous pneumothorax seen at Busan National University Hospital during past 3years were reviewed to study the possible pathogenesis and its effective management. and the results obtained as follows; 1] The incidence of the "spontaneous" pneumothorax which developed without underlying pathology was 13-1%. The majority of those cases was considered as the result of rupture of subpleural blebs. 2] The incidence of secondary pneumothorax which developed with underlying pathology was 50.0%, in which 42.3% was combined with pulmonary tuberculosis and 8, 0% was combined with pulmonary infection. The traumatic pneumothorax was developed in 36-5% of total series. 3] In age distribution, there was pronounced difference between spontaneous and secondary pneumothorax. The majority of spontaneous pneumothorax cases was 20-30 decade and tall and tall and thin in body structure. In secondary pneumothorax, however, the incidence was relatively high in age group more than 50 years old. 4] The incidence of pneumothorax combined with pulmonary tuberculosis was particularly high in our country, and the cause of pneumothorax was seemed due to the rupture of subpleural caseous foci in some cases, but the majority was seen due to the rupture of emphysematous blebs which were formed with a pathological process of chronic tuberculosis. 5]Closed [tube] thoracotomy was the main therapeutic approach of choice in the great majority ,of pneumothorax in our series with the relapse rate of 19.6%. However, open thoracotomy and adequate surgical procedures should be undertaken in patients with continuous air leakage over 7 days and recurrent attack of pneumothorax.

• Journal of Korean Neurosurgical Society
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• v.58 no.3
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• pp.304-307
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• 2015

Only a few cases of anterior longitudinal ligament (ALL) injury related with retropharyngeal hematoma without fracture have previously been reported. The treatment of choice for retropharyngeal hematoma is generally considered to be conservative care, but we believe that early surgery of this pathology would be better in certain situations. Here, we describe two cases with life-threatening large retropharyngeal hematomas related with ALL injuries and operated on at an early stage. Two previously healthy patients visited the emergency room with neck pain and dyspnea after falling. Serious neck swelling was observed and lateral neck X-ray showed severe widening of the prevertebral space. Due to dyspnea progression, emergency endotracheal intubation was performed. Although there was no primary cause of the retropharyngeal hematoma on preoperative examination, ALL tearing was intraoperatively confirmed during early surgery. The in-hospital evolutions of the patients were favorable after surgery. We should bear in mind the possibility of ALL injury and perform early surgery where possible given the earlier convalescence and good prognosis.