• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.6B
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• pp.534-543
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• 2006

As the topology frequently varies, more cluster reconstructing is needed and also management overheads increase in the wireless ad hoc/sensor networks. In this paper, we propose a multi-hop clustering algorithm for wireless sensor network topology management using dynamic pre-clusterhead scheme to solve cluster reconstruction and load balancing problems. The proposed scheme uses weight map that is composed with power level and mobility, to choose pre-clusterhead and construct multi-hop cluster. A clusterhead has a weight map and threshold to hand over functions of clusterhead to pre-clusterhead. As a result of simulation, our algorithm can reduce overheads and provide more load balancing well. Moreover, our scheme can maintain the proper number of clusters and cluster members regardless of topology changes.

• Archives of Plastic Surgery
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• v.47 no.6
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• pp.551-558
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• 2020

Background Giant congenital melanocytic nevus (GCMN) is a rare disease, for which complete surgical resection is recommended. However, the size of the lesions presents problems for the management of the condition. The most popular approach is to use a tissue expander; however, single-stage expansion in reconstructive surgery for GCMN cannot always address the entire defect. Few reports have compared tissue expansion techniques. The present study compared single and serial expansion to analyze the risk factors for complications and the surgical outcomes of the two techniques. Methods We retrospectively reviewed the medical charts of patients who underwent tissue expander reconstruction between March 2011 and July 2019. Serial expansion was indicated in cases of anatomically obvious defects after the first expansion, limited skin expansion with two more expander insertions, or capsular contracture after removal of the first expander. Results Fifty-five patients (88 cases) were analyzed, of whom 31 underwent serial expansion. The number of expanders inserted was higher in the serial-expansion group (P<0.001). The back and lower extremities were the most common locations for single and serial expansion, respectively (P =0.043). Multivariate analysis showed that sex (odds ratio [OR], 0.257; P=0.015), expander size (OR, 1.016; P=0.015), and inflation volume (OR, 0.987; P=0.015) were risk factors for complications. Conclusions Serial expansion is a good option for GCMN management. We demonstrated that large-sized expanders and large inflation volumes can lead to complications, and therefore require risk-reducing strategies. Nonetheless, serial expansion with proper management is appropriate for certain patients and can provide aesthetically satisfactory outcomes.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.19.1-19.7
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• 2015

Background: The purpose of this retrospective study was to investigate the usefulness of tracheostomy scoring system in the decision of postoperative airway management in oral cancer patients. Materials and methods: A total of 104 patients were reviewed in this retrospective study, who underwent radical resection with or without neck dissection and free flap reconstruction due to oral cancer. The patients were classified into three groups according to the timing of the extubation; extubated groups (n = 51), overnight intubation group (n = 45), and tracheostomy group (n = 8). Cameron's score was used to evaluate the relation between the state of the patient's airway and the type of the operation. Results: Tracheostomy was performed in eight patients (8/104, 7.7 %). A total of 22 patients (21.2 %) had more than 5 points of which 17 patients (77.3 %) did not have a tracheostomy and any postoperative emergency airway problems. The tracheostomy scores were significantly different among the three groups. Hospital stay showed a significant correlation with the tracheostomy score. Conclusions: The scoring system did not quite agree with the airway management of the authors' clinic; however, it can be one of the clinical factors predicting the degree of the postoperative airway obstruction and surgical aggressiveness for recovery. The further studies are needed for clinically more reliable scoring systems.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.5
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• pp.81-101
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• 2011

This study was conducted to understand the environmental and ecological function of habitat through evaluation of water environment, soil environment, vegetation characteristics, macro-invertebrate characteristics, and visual habits environment evaluation (SVAP) in Hongdong stream located in Hongseong-Gun, Chungnam Province, and hereafter to utilize the results for the habits reconstruction and improvement project. As the results of water quality analysis, BOD, COD, T-P was almost below the standard quality from upper stream to down stream. The construction of small reservoir, wetland and water purification facility, and the management of non-point pollution are proposed to improve these problems. The soil texture was sandy soil, which is unfitted with vegetation development. The construction of shallows and bogs, and induction of soil sedimentation and biotope formation are proposed to improve these problems. In the plant flora, total 90 kinds were observed with 81 species and nine varieties in total 36 families and 85 genera, and the naturalization rate was higher at down area than upper area. As the results of macro-invertebrate fauna survey, total 26 species and 297 individuals in 20 families and 22 genera were collected. Peltodytes sinensis, Chironomidae sp., and Culicidae sp., which are observed at polluted environment, were collected as dominant species. An appropriate vegetation management party idea is necessary, and it is done an idea in consideration of the soil and a physical characteristic. Visual habits environment evaluation (SVAP) result was mostly determined with below normal (Fair) grade. Pollution source interception, purification pond establishment, and various bog establishment are proposed to improve these problems. With the above results, the ecological environment was determined with bad condition, and the improvement of biotope was urgently needed through sustainable monitoring and management of streams habitat in rural area.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.1
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• pp.12-17
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• 2018

Objectives: Airway management in patients with panfacial trauma is complicated. In addition to involving facial lesions, such trauma compromises the airway, and the use of intermaxillary fixation makes it difficult to secure ventilation by usual approaches (nasotracheal or endotracheal intubation). Submental airway derivation is an alternative to tracheostomy and nasotracheal intubation, allowing a permeable airway with minimal complications in complex patients. Materials and Methods: This is a descriptive, retrospective study based on a review of medical records of all patients with facial trauma from January 2003 to May 2015. In total, 31 patients with complex factures requiring submental airway derivation were included. No complications such as bleeding, infection, vascular, glandular, or nervous lesions were presented in any of the patients. Results: The use of submental airway derivation is a simple, safe, and easy method to ensure airway management. Moreover, it allows an easier reconstruction. Conclusion: Based on these results, we concluded that, if the relevant steps are followed, the use of submental intubation in the treatment of patients with complex facial trauma is a safe and effective option.

• The Journal of the Korean dental association
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• v.54 no.10
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• pp.811-819
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• 2016

Panfacial fracture is extremely difficult to manage facial injuries but concomitant injuries and severe complications including facial esthetic and functional problems can make it harder. Thorough evaluation and closed co-work with other specialists is needed when reduction and fixation cannot be achieved quickly. Emergency bony support and soft tissue key suture provide the patients with airway integrity, hard and soft tissue vitality. A systemic treatment plan must be made by 3D CT image. This plan include airway management for surgery, sequence of reduction and fixation, approach method, soft tissue resuspension and reconstruction of lost tissue like inferior orbital wall, zygomaic buttress and soft tissue. From known to unknown structures, accurate reduction and fixation will provide proper occlusion, facial projection, width, hight and function. Consideration about facial retaining ligaments must be given to prevent soft tissue sagging.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.321-333
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• 2017

This study was a qualitative study using Colaizzi's phenomenological study method to understand the experience of reconstructing life through hemodialysis in chronic renal failure patients and to clarify the meaning of their vivid experience. The participants were eight chronic renal failure patients receiving hemodialysis. Data were collected through individual in - depth interviews with participants. The five categories that were found in the study were 'The beginning of unexpected difficulties', 'Burden of survival brought on by hemodialysis', 'The driving force of recovery', 'Choices and concentration of today in order', ' Every day life which must be woven sincerely'. The results of this study will help clinicians better understand the physical and mental suffering experienced by patients with chronic renal failure receiving hemodialysis and how they are constantly trying to adapt to a changed lifestyle. Also it might provide basic data for the development of efficient nursing intervention for the health management of hemodialysis patients.

• Archives of Craniofacial Surgery
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• v.13 no.1
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• pp.46-49
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• 2012

Purpose: The forehead flap is the workhorse in nasal reconstruction, which provides a similar skin color, texture, structure, and reliability. There are some disadvantages, including donor site morbidities, 2- or 3-stage operations, and postoperative management after initial flap transfer. Furthermore, there has been little attention to the exposed raw surface wound, after the first stage of an operation. This article describes the authors' modification to overcome this problem, using artificial collagen membrane. Methods: An Artificial collagen membrane is composed of an outer silicone membrane and an inner collagen layer. After a forehead flap elevation, the expected raw surface was covered by an artificial collagen membrane with 5-0 nylon suture. A simple dressing, which had been applied to the site, was changed every 2 or 3 days in an outpatient unit. At 3 weeks postprocedure, a second stage operation was performed. Results: With biosynthetic protection of the raw surface, there were no wound problems, such as infection or flap loss. Thus, the patient was satisfied due to an effortless management of the wound and a reduction in pain. Conclusion: The application of an artificial collagen membrane to the raw under-surface of the flap could be a comfortable and a protective choice for this procedure.

• Annals of Surgical Treatment and Research
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• v.95 no.6
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• pp.324-332
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• 2018

Purpose: We present our experience involving the management of this disease, identifying prognostic factors affecting treatment outcomes. Methods: The patients treated for Fournier gangrene at our institution were retrospectively reviewed. Data collected included demographics, extent of soft tissue necrosis, predisposing factors, etiological factors, laboratory values, and treatment outcomes. The severity index and score were calculated. Multivariate regression analysis was used to determine the association between potential predictors and clinical outcomes. Results: A total of 41 patients (male:female = 33:8) were studied. The mean age was 54.4 years (range, 24-79 years). The most common predisposing factor was diabetes mellitus (n = 19, 46.3%). Sixteen patients (39.0%) were current smokers. Seven patients had chronic kidney disease. The most frequent etiology was urogenital lesion (41.5%). The mortality rate was 22.0% (n = 9). Multivariate regression analyses showed that extension of necrosis beyond perineal/inguinal area and pre-existing chronic kidney disease were significant and independent predictors of mortality. Extension of necrosis beyond perineal/inguinal area was a significant predictor of increased duration in the intensive care unit and hospital stay. In addition, pre-existing chronic kidney disease was a significant predictor of flap reconstruction in the wound. Conclusion: Fournier gangrene with extensive soft tissue necrosis and pre-existing chronic kidney disease was associated with poor prognosis and complexity of patient management. Early recognition of dissemination and premorbid renal function is essential to reduce mortality and establish a management plan for this disease.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.792-799
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• 2022

Building Information Modeling (BIM) technology is a key component of modern construction engineering and project management workflows. As-is BIM models that represent the spatial reality of a project site can offer crucial information to stakeholders for construction progress monitoring, error checking, and building maintenance purposes. Geometric methods for automatically converting raw scan data into BIM models (Scan-to-BIM) often fail to make use of higher-level semantic information in the data. Whereas, semantic segmentation methods only output labels at the point level without creating object level models that is necessary for BIM. To address these issues, this research proposes a hybrid semantic-geometric approach for clutter-resistant floorplan generation from laser-scanned building point clouds. The input point clouds are first pre-processed by normalizing the coordinate system and removing outliers. Then, a semantic segmentation network based on PointNet++ is used to label each point as ceiling, floor, wall, door, stair, and clutter. The clutter points are removed whereas the wall, door, and stair points are used for 2D floorplan generation. A region-growing segmentation algorithm paired with geometric reasoning rules is applied to group the points together into individual building elements. Finally, a 2-fold Random Sample Consensus (RANSAC) algorithm is applied to parameterize the building elements into 2D lines which are used to create the output floorplan. The proposed method is evaluated using the metrics of precision, recall, Intersection-over-Union (IOU), Betti error, and warping error.