• Journal of Electrical Engineering and Technology
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• v.13 no.6
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• pp.2245-2253
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• 2018

With the increase of electrical consumption and the unbalance of power demand and supply, power reserve rate is getting smaller and also the reliability of the power supply is getting deteriorated. Under this circumstance, the electrical energy storage (EES) System is considered as one of essential countermeasure for demand side management. This paper proposes efficient evaluation algorithms of multiple functions for EES systems, especially the secondary battery energy storage systems, in the case where they are interconnected with the power distribution systems. It is important to perform the economic evaluation for the new energy storage systems in a quantitative manner, because they are very costly right now. In this paper, the multiple functions of EES systems such as load levelling, effective utilization of power distribution systems and uninterruptible power supply are classified, and then the quantitative evaluation methods for their functions are proposed. From the case studies, it is verified that EES systems installed at distribution systems in a dispersed manner have multiple functions involved with direct and indirect benefits and also they can be expected to introduce to distribution systems with respects to economical point of view.

• Archives of Plastic Surgery
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• v.44 no.2
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• pp.162-165
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• 2017

Multiple osteochondromas (MO) is characterized by the formation of osteochondromas throughout the entire body. Although the evidence regarding its pathogenesis is well understood, no curative treatment for the disorder is available. Patients can be treated symptomatically by surgical removal of painful osteochondromas. Unfortunately, some patients still suffer from severe pain, even after surgery. We report on a case concerning a 48-year-old woman with a history of MO who presented with persistent pain after surgical removal of a symptomatic osteochondroma of the left scapula and multiple symptomatic osteochondromas of the left foot and trochanteric region. Several interventions to reduce the pain did not have any lasting effect. Subsequently, she was treated with autologous fat grafting (AFG). After each session she was pain-free for at least one year and reported only partial recurrence of the pain. This is the first case report describing AFG for the treatment of pain after both surgical removal of an osteochondroma and symptomatic osteochondromas in a patient suffering MO with promising results. The treatment is more effective and clearly continues to remain active longer than injection therapy or pain medication. Future studies are necessary to confirm our results.

• Tuberculosis and Respiratory Diseases
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• v.72 no.1
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• pp.88-92
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• 2012

A 37 year old female presented with epigastric pain and weight loss over a period of 3 months. Her abdominal CT finding showed a 4.5 cm size hepatic mass and 4.3 cm size pancreatic head mass with multiple macronodules in the liver. At the same time, her chest CT revealed a 5 cm size necrotic mass in the left lower lobe of the lung with multiple bilateral pulmonary nodules. We diagnosed these lesions as tuberculosis through multiple biopsies. She was treated with anti-tuberculous medication. After taking the medications, her symptoms were improved. Twelve months later, imaging studies indicated an improvement in the patient's health. Here we report a case report of multi-organ macronodular tuberculosis in lung, liver and pancreas.

• Communications for Statistical Applications and Methods
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• v.17 no.6
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• pp.899-907
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• 2010

Several non-response imputation methods are suggested, however, mainly cross-sectional imputations are studied and applied to this analysis. A simple and common imputation method for panel data is the cross-wave regression imputation or carry-over imputation as a special case of cross-wave regression imputation. This study suggests a multiple imputation method combined time series analysis and cross-sectional multiple imputation method. We compare this method and the cross-wave regression imputation method using MSE, MAE, and Bias. The 2008 monthly labor survey data is used for this study.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.3
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• pp.172-177
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• 2023

The main purpose of the research was to review the global trends of airport's smart security technologies. Moreover, using the case studies of airport using smart security, this paper tried to propose the implication how the findings through the case studies may be important for airport policy and will impact the future research of airport operation. It is expected in the future the aviation security technology with biometric information evolves from single identification to multiple identification technology which has combined application of iris, vein and others. Facing post COVID-19 era, the number of passengers traveling through airports continues increase dramatically and the risks as well, the role of AI becomes even more crucial. With AI based automated security robotics airport operators could effectively handle the growing passenger and cargo volume and address the associated issues Smart CCTV analysis with A.I. and IoT applying solutions could also provide significant support for airport security.

• Journal of Korean Neurosurgical Society
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• v.54 no.2
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• pp.151-154
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• 2013

Multiple myeloma, a multicentric hematological malignancy, is the most common primary tumor of the spine. As epidural myeloma causing spinal cord compression is a rare condition, its therapeutic approach and clinical results have been reported to be diverse, and no clear guidelines for therapeutic decision have been established. Three patients presented with progressive paraplegia and sensory disturbance. Image and serological studies revealed multiple myeloma and spinal cord compression caused by epidural myeloma. Emergency radiotherapy and steroid therapy were performed in all three cases. However, their clinical courses and results were distinctly different. Following review of our cases and the related literature, we suggest a systematic therapeutic approach for these patients to achieve better clinical results.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.4
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• pp.474-481
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• 2017

This paper presents a multiple target tracking system using Normalized Rayleigh likelihood of amplitude information of target. Although many studies of Radar systems using amplitude information have been studied, they are focused on single target tracking. This paper proposes the multiple target tracking using amplitude information as well as kinematic information from Radar sensor. The amplitude information are applied in generating the association probability of joint probabilistic data association(JPDA) algorithm through the normalized Rayleigh likelihood. It is verified that the proposed system can enhance the track maintenance and tracking accuracy, especially, in the target crossing case.

• Communications for Statistical Applications and Methods
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• v.30 no.1
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• pp.1-19
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• 2023

Observational data with missing or incomplete data are common in biomedical research. Multiple imputation is an effective approach to handle missing data with the ability to decrease bias while increasing statistical power and efficiency. In recent years propensity score (PS) matching has been increasingly used in observational studies to estimate treatment effect as it can reduce confounding due to measured baseline covariates. In this paper, we describe in detail approaches to competing risk analysis in the setting of incomplete observational data when using PS matching. First, we used multiple imputation to impute several missing variables simultaneously, then conducted propensity-score matching to match statin-exposed patients with those unexposed. Afterwards, we assessed the effect of statin exposure on the risk of heart failure-related hospitalizations or emergency visits by estimating both relative and absolute effects. Collectively, we provided a general methodological framework to assess treatment effect in incomplete observational data. In addition, we presented a practical approach to produce overall cumulative incidence function (CIF) based on estimates from multiple imputed and PS-matched samples.

• Journal of Acupuncture Research
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• v.29 no.3
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• pp.19-28
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• 2012

Objectives : The aim of this study is to evaluate present clinical evidence of oriental medical treatment for cancer in Korea. Method : A search was performed in the Korean Studies Information, Korea Institute of Science and Technology Information, KoreaMed, Oriental Medicine Advanced Searching Integrated System, National Assembly Library, RISS4u, DBPIA, and Oasis using the keyword 'cancer', 'leukemia', 'malignant tumor', 'lymphoma', 'multiple myeloma', 'melanoma'. The search period spanned between Jan 1, 1980~June 30, 2011 and the results were analyzed and evaluated according to the publication date, journal, method of treatment, type of study, and the primary outcome. Randomized clinical trials (RCTs) and Non randomized clinical trial(NRCT) were reviewed separately. Result : The results yielded 133 trials during the period of Jan 1, 1980~June 30, 2011. Most of the trials were concerned with lung cancer and 94 of the trials were simple case studies or case series studies. 61 trials used herbal Formula/herbal medicine as the primary method of treatment. A total of 4 RCTs existed compared to only one NRCT. Conclusion : The use of oriental medicine for the treatment of cancer is gaining popularity in the field of medical scientific research. However most of the studies that have been published up to date are mostly case studies or case series studies, and RCT/NRCT are rare. In order to provide appropriate evidence regarding the effectiveness of oriental medicine in the treatment of cancer, more rigorous and well-designed studies are warranted.

• Archives of Craniofacial Surgery
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• v.20 no.4
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• pp.260-264
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• 2019

Dysplastic nevus is common and affects about 10% of the northern European-descendent population. Studies over the past several decades have identified dysplastic nevi as a risk factor for malignant melanoma. Furthermore, in rare cases, they confirmed that dysplastic nevi have progressed to melanoma. Cases in which dysplastic nevi progressed to malignant melanoma in multiple studies are not uncommon. A 35-year-old woman presented with the major symptom of multiple itchy brown nodules ($2.0cm{\times}1.3cm$) in the left cheek that had first appeared 20 years earlier. Complete excision was performed at the first visit; subsequent biopsy confirmed that they were dysplastic nevi. They recurred three times over 3 years at the same site, all of which were histologically diagnosed as dysplastic nevi. Five years after the final excision, a brownish nodule developed in the left cheek, with others at the left temporal region, right retroauricular region, and left shoulder at the same time. These lesions were histologically diagnosed as malignant melanoma. We experienced a case of malignant melanoma that occurred at the same site after three recurrences of dysplastic nevi. Although rare, the possibility of malignant melanoma should be considered in follow-ups in cases involving repeatedly recurrent dysplastic nevi.