• Korean Journal of Heritage: History & Science
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• v.54 no.2
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• pp.194-215
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• 2021

Termites are important decomposers in the ecosystem. They are also economically significant structural pests. In this study, we reviewed the developments of termite control and recent research on termite management to provide information on the prevention and control of termites. In Korea, most of the damage to wooden historical buildings is caused by subterranean termites. Reticulitermes speratus kyushuensis is the main species, which is widely found throughout the country. In the early 1900s, inorganic insecticides, such as arsenic dust, were used for termite control. After the synthesis of chlorinated hydrocarbon pesticide in the 1940s, it was widely utilized and demonstrated high termite control efficacy. However, chlorinated hydrocarbon insecticides were later banned, disappearing from markets after reports emerged concerning environmental contamination and toxicity to humans. Therefore, the termite control industry sought a new termiticide; hence many pesticides were utilized for termite control. Organophosphate (1960s), carbamate (1970s), pyrethroid, and insect growth inhibitor (1980s) were newly synthesized and adopted. In the 1990s, the first commercial baits using chitin synthesis inhibitors (CSI) were developed, providing a means to eliminate an entire colony of subterranean termites around a structure. Many studies have been carried out on soil termiticides (liquid termiticides) and CSI baits to increase their efficacy, and different baits such as aboveground bait stations, fluid bait, and high-durability bait were also developed in the 2000s. In addition, the paradigm of termite control has shifted from localized treatments using soil termiticides to area-wide pest management using CSI baits to create termite-free zones and protect buildings over time. Termite infestations in wooden historical buildings in Korea have been reported since 1980, and considerable attention was drawn in the 1990s when several UNESCO world heritages such as the Jongmyo Shrine and the Janggyeong Panjeon Depositories of Haeinsa Temple were infested by subterranean termites. Since then, a survey of termite infestation in wooden architectural heritage has been conducted, and the National Research Institute of Cultural Heritage and Heritage Care Program regularly monitors those properties. Finally, we suggest termite management using primarily CSI baits, selective application of various soil treatments applied to the object, foundation soil treatment, research and development of durable termite baits, application of area-wide programs for wooden-building complexes, application of integrated termite management (ITM), and regular education for owners and managers to prevent and reduce termite damage.

• Clinical and Experimental Pediatrics
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• v.51 no.1
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• pp.89-92
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• 2008

A subcapsular liver hematoma (SLH) is a relatively common lesion in fetuses and neonates. Although an SLH ruptures rarely, it may be life threatening. We report on a term neonate with a delayed rupture of an SLH that occurred on day 7 of life. The infant had been resuscitated with intubation, positive pressure ventilation, and chest compression at birth because of meconium-associated perinatal depression. The SLH was diagnosed by abdominal ultrasonography and paracentesis, and the ruptured SLH was treated operatively. After intensive medical and surgical management, the infant was discharged healthy on day 27 of life. A newborn infant presenting with the sudden onset of extreme shock and pallor associated with abdominal distension should undergo differential diagnosis for SLH and a clinical evaluation concurrent with fluid resuscitation and timely surgery.

• Tuberculosis and Respiratory Diseases
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• v.57 no.4
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• pp.381-385
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• 2004

Pulmonary gangrene is a rare and severe complication of bacterial pneumonia, where a pulmonary segment or lobe is sloughed due to parenchymal devitalization of the parenchyma, with secondary anaerobic infection and necrosis caused by pulmonary vascular thrombosis. Prior to the antibiotic era, massive pulmonary gangrene was potentially fatal. Herein, a case of pulmonary gangrene in a 67-year-old man is reported. He complained of fever, chills, dyspnea and purulent sputum of 5 days duration. The plain chest radiograph showed well-marginated right upper lobe consolidation, with bulging minor fissure, suggestive of a Klebsiella infection. A contrast CT scan demonstrated consolidation of the right upper lobe, with a central necrotizing portion. Klebsiella species was confirmed from both sputum and blood cultures. After appropriate antibiotics, the chest X-ray and CT scan 3 weeks later showed a large cavity with an air-fluid level, sloughing-off and extrusion of necrotic lung tissue, suggestive of pulmonary gangrene. Seven months later, the right gangrenous lung showed severe volume loss on a chest radiograph. The management of pulmonary gangrene has been somewhat controversial. Herein, it was managed without surgical drainage or resection. If the antibiotic therapy had failed, then a surgical approach would have been considered.

• Journal of Digital Convergence
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• v.11 no.8
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• pp.199-204
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• 2013

Computational fluid dynamics (CFD) is used to reduce number of experiments. The CFD tools are widely used for engine design and flow pattern analysis to reduce experiments. In this study the performance of a PEMFC single cell was analyzed by using STAR-CD, product of CD-ADAPCO. The effect of cell design and flow pattern on the performance of a PEMFC was analyzed with the 3-D simulation. As a result the performance of rectangular cell was the higher than that of square cell, while the flow direction scarcely affected on the performance of a PEMFC. Also the current density according to different excess ratio of air flow rate was compared and analyzed. The difference between maximum and minimum current density of flip-flow was lower than that of co-flow.

• Journal of Korean Neurosurgical Society
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• v.41 no.2
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• pp.100-104
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• 2007

Objective : Despite the widespread use of preoperative ventriculostomy in aneurysmal subarachnoid hemorrhage [SAH], there is no general consensus regarding the risk of bleeding associated with its use before aneurysm repair. This study was conducted to define the efficacy and rebleeding risk of ventriculostomy in aneurysmal SAH. Methods : The authors reviewed 339 consecutive patients with aneurysmal SAH who were treated at our hospital between January 1998 and December 2004. Results : Preoperative ventriculostomy was performed on 73 patients for acute hydrocephalus after aneurysmal SAH. The Hunt-Hess[H-H] grades of patients who underwent ventriculostomy were higher. Out of the 73 patients who underwent preoperative ventriculostomy, 58 [79%] demonstrated immediate clinical improvement after ventriculostomy. Of those same 73 patients 22 [30%] suffered aneurysmal rebleeding, whereas only 11 [4%] of the 266 patients who did not undergo ventriculostomy showed preoperative aneurysm rebleeding. The causes of rebleeding in the 22 patients who underwent ventriculostomy before surgery were related to the ventriculostomy procedure itself, subsequent cerebrospinal fluid [CSF] drainage, angiography and patient care procedures, such as endotracheal suction and nursing care. The mean time interval between SAH and surgery in the patients who underwent ventriculostomy was not statistically different from those who did not receive preoperative ventriculostomies [44.66 compared with 42.13 hours; p=0.73]. Conclusion : The preoperative ventriculostomy improved patients' clinical condition but increased the risk of rebleeding after aneurysmal SAH. When necessary, however, rapid change in transmural pressure during ventriculostomy must be avoided, careful management during ventricular drainage is needed, and surgery should be performed as soon as possible to prevent or reduce the incidence of rebleeding.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.5
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• pp.737-746
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• 2017

In 2017, amid changes in the security market such as integrated security (IS) and convergence security (CS), a variety of security paradigms in terms of operation and management have been suggested. Rather than changing existing network infrastructure and bringing about fluid, multi-dimensional changes, these solutions and technologies focus entire security capacity on a primary protection, leading to network infrastructure suffering from unexpected inherent violations and problems in a continued manner. Therefore, it is time to propose and develop a flexible network section that can protect from attacks of similar pattern and concentrated traffic attacks by applying a new concept of WB (Water-Bubble) to network infrastructure and analyzing on the basis of experiment and installation. Methodology of the WB-based highly secure flexible network section proposed in this study is expected to provide materials for studies on how to achieve network section security taking into account three major limitations and security standards: fluidity, unpredictability, and non-area scalability by contact point ratio, by changing a network area predicted to be the final target of attack into resonant network section (area) with flexible area changes.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2008.04a
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• pp.101-108
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• 2008

Polymer electrolyte membrane (PEM) fuel cells are promising power generation devices which are ideal for residential and automobile applications, thanks to their fast transient characteristics. However, liquid water produced in PEM fuel cells should be properly managed to enhance the performances and durabilities of the cells. In this study, a visualization experiment was conducted to investigate the flow behavior of water droplets in cathode channels. The visualization experiment was done with four different model flow channels which were made by varying the material (Acrylic and Teflon) and the channel width (1 mm and 2 mm). Acrylic is hydrophilic (contact angle is about $80^{\circ}$) while Teflon is hydrophobic (contact angle is about $120^{\circ}$). A computational fluid dynamics (CFD) analysis was also performed to compare the observed and the simulated two-phase water/air flow characteristics in cathode channels. The computational models were made to be consistent with the geometries and surface properties of the model flow channels. Both the experimental and numerical results showed that the Teflon cathode channel with 1 mm width has the best water management performance among four model flow channels considered. A close correlation was found between the experimental visualization results and the numerical CFD simulation results.

• Fire Science and Engineering
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• v.26 no.5
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• pp.54-60
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• 2012

This study is the analysis of the actual state of hospital-based training in level 1 emergency medical technicians (EMTs) in fire station. The survey was carried out to 42 fire fighters having level 1 emergency medical technician certification from May 11 to 12 in 2012. The results showed 56.5 %, that the level 1 EMTs of roles had direct experienced. Level 1 EMTs performance frequency of clinical practice that endotracheal intubation 66.9 %, laryngeal mask airway 8.4 %, intravenous access 76.6 %, nitroglycerin sublingual 61.2 %, bronchodilator inhalation 50.0 %, fluid loading 73.8 %, ventilator apply 57.6 %, dextrose injection 57.6 %. It is necessary to investigate the continuous study on the education among the level 1 EMTs and the continuous evaluation and analysis of problems, supplemented of guidebook, practical education programs and regulation upon the operation and management of a hospital-based skill training.

• Journal of Veterinary Clinics
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• v.26 no.4
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• pp.336-339
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• 2009

A 4-year-old, neutered male Shih-tzu dog weighing 5.4 kg was referred due to anorexia and chronic coughing. Based on history, physical examination, laboratory tests, radiographic findings, echocardiography, and bronchoscopic examination, the dog was diagnosed as tracheobronchial foreign body. The foreign body was steamed rice debris, which was removed by bronchoalveolar lavage (BAL) with vacuum suction of bronchoscopy. Bacterial and fungal culture of collected BAL fluid was negative. Baermann test for lungs parasites also was negative. The dog was treated with bronchodilator, antibiotics, anti-inflammatory agent, and mucolytics for 7 days. Appetite increased and coughing sign was clearly improved after removal of foreign body and medical therapy. This case report describes that bronchoscopic techniques are available for the evaluation and management of airway foreign bodies.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.5
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• pp.1384-1396
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• 1998

This paper ivestigates the performance of a relative rate (RR) switch algorithm for the rate-based available bit rate (ABR) flow control in asynchronous transfer mode (ATM) networks. A RR switch may notify the network congestion status to the source by suing the congestion indication (CI) bit or no increase (NI)bit in the backward RM (BRM) cells. A RR switch can be differently implemented according to the congestion detectio and notification methods. In this paper, we propose three implementation schemes for the RR switch with different congestion detection and notification methods, and analyze the allowed cell rate (ACR) of a source and the queue length of a switch in steady state. In addition, we derive the upper and lower bounds for the maximum and minimum queue lengths for each scheme respectively, and evaluate the effects of the ABR parameter values on the queue length. Furthermore, we suggest the range of the rage increase factor (RIF) and rate decrease factor (RDF) parameter values which can prevent buffer overflow and underflow at a switch.