• 한국안전학회지
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• 제9권4호
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• pp.77-84
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• 1994

A study is performed in order to design a effective ventilation equipment for the pollutants in workshop. The procedure has been used to calculate the flow in a confined rectangular space channel. A cross free stream is flowed from open space and jet stream including pollutants is injected from bottom area. Calculation results shows a wake region which exists immediarely downstream of the jet discharge and are compared with the experimental data. Calculation data are in good agreement with experimental results. A wake plays an important role on a stagnation of the pollutants. Thus ventilation equipment has to be designed without a stagnation region which give rise to concentration stratification. In this study, calculation parameters are the position and velocity of pollutants and fresh air from cross free stream. It is concluded that more measurements of local velocities, temperatures and concentrations of the pollutants.

• Environmental Engineering Research
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• 제11권3호
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• pp.164-171
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• 2006

Numerical modeling of the flow velocity fields for the near corona wire electrohydrodynamic (EHD) flow was conducted. The steady, two-dimensional momentum equations have been computed for a wire-plate type electrostatic precipitator (ESP). The equations were solved in the conservative finite-difference form on a fine uniform rectilinear grid of sufficient resolution to accurately capture the momentum boundary layers. The numerical procedure for the differential equations was used by SIMPLEST algorithm. The Phoenics (Version 3.5.1) CFD code, coupled with Poisson's electric field, ion transport equations and the momentum equation with electric body force were used for the numerical simulation and the Chen-Kim ${\kappa}-{\varepsilon}$ turbulent model numerical results that an EHD secondary flow was clearly visible in the downstream regions of the corona wire despite the low Reynolds number for the electrode ($Re_{cw}=12.4$). Secondary flow vortices caused by the EHD increases with increasing discharge current or EHD number, hence pressure drop of ESP increases.

• 설비공학논문집
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• 제11권3호
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• pp.401-413
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• 1999

An ice storage cooling facility with cooling capacity of 150㎾ has been constructed for the purpose of developing optimal design and control strategy for an ice storage system. As the first step to this purpose, a computer program has been developed to simulate the operation of the ice storage system and examined precisely by comparing the results with those measured from the test facility. With the simulation program verified from the comparison, a design procedure has been developed to determine the minimum capacity required for each operation strategy available commercially. It is shown that the minimum sizes of the chiller and the storage tank are strongly dependent on the control strategy, i.e., chiller priority or storage priority, but less affected by the arrangement method, i.e., chiller upstream or chiller downstream.

• 대한전기학회논문지
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• 제37권10호
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• pp.683-693
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• 1988

For the economical and reasonable operation of electric power system according to continual increase of electric power demand and decrease of load factor, the potential application of superconducting magnertic energy storage [SMES] with high efficiency and fast response in the electric utility is receiving attractive attension. In the light of this background, to confirm the basic principle of SMES, theoretical study, design technique and fabrication procedure for superconducting coil, current lead, cryostat, measuring and protection system of SMES are described in detail. Especially, a new design technique for superconducting coil and current lead is porposed and it was proved experimentally by the performance test of SMES which is developed for the first time in our country. At the peak operating current 200A, the maximum magnetic field amd stored energy of the coil are 3.52T and 2500J, espectively. The thermal and mechanical stability of 2500J SMES is also confirmed experimetally by its characteristics test, AC loss, protection system, charge and discharge test. The experimetal results show good characteristics of energy storage system.

• Structural Engineering and Mechanics
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• 제45권2호
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• pp.169-182
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• 2013

The mechanical behavior of rectangular foundation plates with perimetric beams and internal stiffening beams of the plate is herein analyzed, taking the foundation design into account. A series of dimensionless parameters related to the geometry of the studied elements were defined. In order to generalize the problem statement, an initial settlements was considered. A numeric procedure was developed for the resolution by means of the Finite Differences Method that takes into account the stiffness of the plate, the perimetric and internal plate beams and the soil reaction module. Iterative algorithms were employed which, for each of the analyzed cases, made it possible to find displacements and reaction percentages taken by the plate and those that discharge directly into the perimetric beams, practically without affecting the plate. To enhance its mechanical behavior the internal stiffening beams were prestressed and the results obtained with and without prestressing were compared. This analysis was made considering the load conditions and the soil reaction module constant.

• 고신대학교 의과대학 학술지
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• 제33권3호
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• pp.396-401
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• 2018

Extraction of old pacemaker leads remains a complex procedure owing to fibrotic encapsulation and lead adhesions. We report a case of extraction of 15-year-old pacemaker leads by weight and pulley method. A 81-year-old man presented with exposed pacemaker leads out of body with purulent discharge from a pacemaker insertion site. He inserted DDD (dual chamber pacing, dual chamber sensing dual function) pacemaker implantation 15 years ago for SSS. Previously pacemaker battery was removed 3 years ago due to recurrent infection of pacemaker scar site. We extracted the pacemaker leads by weight and pulley method successfully without any complications.

• Journal of Yeungnam Medical Science
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• 제39권1호
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• pp.67-71
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• 2022

This report describes a case of coinfection of Sphingomonas paucimobilis meningitis and Listeria monocytogenes bacteremia in a 66-year-old immunocompetent female patient. The patient had undergone traditional procedures, including acupuncture, which possibly caused the coinfection. During treatment with susceptible antibiotics for bacterial meningitis, she developed hydrocephalus on the third day. Consequently, the patient recovered with a mild neurological deficit of grade 4 motor assessment in both upper and lower extremities at discharge. S. paucimobilis and L. monocytogenes are rare pathogens in developed countries, occurring only during environmental outbreaks. S. paucimobilis meningitis is rarely reported. Hence, the various presentations of S. paucimobilis meningitis and the antibiotic regimen for its treatment are hereby reported, in addition to a review of other similar reported cases. This case is a possible traditional procedure-related infection. Appropriate oversight and training should be emphasized regarding preventive measures of this kind of infection. A team approach with neurologists and neurosurgeons is imperative in treating patients with hydrocephalus-complicated meningitis.

• Journal of Korean Neurosurgical Society
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• 제65권2호
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• pp.224-235
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• 2022

Objective : Since the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, neurointerventionists have been increasingly concerned regarding the prevention of infection and time delay in performing emergency thrombectomy procedures in patients with acute stroke. This study aimed to analyze the effects of changes in mechanical thrombectomy protocol before and after the COVID-19 pandemic on procedure time and patient outcomes and to identify factors that significantly impact procedure time. Methods : The last-normal-to-door, first-abnormal-to-door, door-to-imaging, door-to-puncture, and puncture-to-recanalization times of 88 patients (45 treated with conventional pre-COVID-19 protocol and 43 with COVID-19 protection protocol) were retrospectively analyzed. The recanalization time, success rate of mechanical thrombectomy, and modified Rankin score of patients at discharge were assessed. A multivariate analysis was conducted to identify variables that significantly influenced the time delay in the door-to-puncture time and total procedure time. Results : The door-to-imaging time significantly increased under the COVID-19 protection protocol (p=0.0257) compared to that with the conventional pre-COVID-19 protocol. This increase was even more pronounced in patients who were suspected to be COVID-19-positive than in those who were negative. The door-to-puncture time showed no statistical difference between the conventional and COVID-19 protocol groups (p=0.5042). However, in the multivariate analysis, the last-normal-to-door time and door-to-imaging time were shown to affect the door-to-puncture time (p=0.0068 and 0.0097). The total procedure time was affected by the occlusion site, last-normal-to-door time, door-to-imaging time, and type of anesthesia (p=0.0001, 0.0231, 0.0103, and 0.0207, respectively). Conclusion : The COVID-19 protection protocol significantly impacted the door-to-imaging time. Shortening the door-to-imaging time and performing the procedure under local anesthesia, if possible, may be required to reduce the door-to-puncture and door-to-recanalization times. The effect of various aspects of the protection protocol on emergency thrombectomy should be further studied.

• 한국간호교육학회지
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• 제6권2호
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• pp.287-302
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• 2000

The purpose of the study are to examine the perception of the importance and performance of patient education of the clinical nurse and find out the interfering factors in practicing patient education. The data were collected from convenient sample of 256 clinical nurses working in the nursing units of adult patients except the psychiatric unit, obstetric unit, dental surgical unit and intensive care unit of one University Hospital in Seoul from September 29 to October 2, 1998. Three measurement tools of self-report- questionnaires developed by researcher used. For the content validity of the questionnaires, two sessions of panel discussion and a pilot test were done and finally factor analysis was done with Varimax method. Analysis of data was done with SAS program using frequency, percentage, means, standard deviation, Pearson's Correlation Coefficients, t-test and ANOVA. The obtained results were as follows : 1. The surveyed nurses perceived the importance of patient education at higher level with mean score of 4.08 among 5 point than their perception of practice( mean score : 3.42). 2. There was positive significant correlation(r=.29, p=0.0001)between nurses' perception of the importance of patient education and it's practice 3. Among the teaching contents for patients, 'information of diagnostic procedure and operation' and 'orientation of hospitalization' were perceived most important. And 'preparation for discharge' and 'understanding of disease and health promotion' were perceived least important 4. Among the teaching contents for patients, 'orientation of hospitalization' and 'information of diagnostic procedure and operation' were perceived highly performable. And 'understanding of disease and health promotion' and 'preparation for discharge' were perceived least performable. 5. Three types of interfering factors were identified as patient-factor, situational factor, nurse-factor. The mean degree of impediment with the interfering factors was at average level(3.09 among 5). The patient and situational factors of impediments were more interfering than nurse- factor for teaching patients. 6. In older age(p<.05), married state (p<.05), higher educational status (p<.01), higher clinical experience (p<.01) and higher position(p<.01), the score of perceived importance of patients education was more high. 7. In older age(p<.01), higher clinical experience(p<.001) and surgical unit (p<.01), the score of perceived performance of patients education was more high. In conclusion, in order to activate patient education practice in the clinical setting, the continuing education for patients education should be more emphasized and the effective teaching methods and materials should be developed to help patient teaching. And an organizational support such as budgeting for patient education and reimbursement system should be administrated.

• Journal of Korean Neurosurgical Society
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• 제62권4호
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• pp.405-413
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• 2019

Objective : We evaluated efficacy of combining proximal balloon guiding catheter (antegrade flow arrest) and distal access catheter (aspiration at the site of occlusion) in thrombectomy for anterior circulation ischemic stroke. Methods : We retrospectively analyzed 116 patients who underwent mechanical thrombectomy with stent retriever. The patients were divided by the techniques adopted, the combined technique (proximal balloon guiding catheter and large bore distal access catheter) group (n=57, 49.1%) and the conventional (guiding catheter with stent retriever) technique group (n=59, 50.9%). We evaluated baseline characteristics (epidemiologic data, clinical and imaging characteristics) and procedure details (the number of retrieval attempts, procedure time), as well as angiographic (thrombolysis in cerebral infarction (TICI) score, distal thrombus migration) and clinical outcome (National Institutes of Health Stroke Scale at discharge, modified Rankin Scale [mRS] at 3 months) of them. Results : The number of retrieval attempts was lower (p=0.002) and the first-pass successful reperfusion rate was higher (56.1% vs. 28.8%; p=0.003) in the combined technique group. And the rate of final result of TICI score 3 was higher (68.4% vs. 28.8%; p<0.01) and distal thrombus migration rate was also lower (15.8% vs. 40.7%; p=0.021) in the combined technique group. Early strong neurologic improvement (improvement of National Institutes of Health Stroke Scale ${\geq}11$ or National Institutes of Health Stroke Scale ${\leq}1$ at discharge) rate (57.9% vs. 36.2%; p=0.02) and favorable clinical outcome (mRS at 3 months ${\leq}2$) rate (59.6% vs. 33.9%; p=0.005) were also better in the combined technique group. Conclusion : The combined technique needs lesser attempts, decreases distal migration, increases TICI 3 reperfusion and achieves better clinical outcomes.