• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.368-369
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• 2011

This article suggests an online-based remote fault current mode discrimination method in order to identify the causes of the power line faults with various causes. For that, it refers to existing cause identification methods and categorizes modes by fault causes based on statistical techniques beforehand and performs the pretreatment process of fault currents by each cause acquired from the fault recorder into a topological plane in order to extract the characteristics of fault currents by each cause. After that, for the fault mode categorization, it discriminates modes by each cause using data by each cause as leaning data through utilizing RBF network based on FCM allowing self-organization in deciding the middle layer. And then it tests the validity of the suggested method as applying it to the data of the actual fault currents acquired from the fault recorder in the electric power transmission center.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.86-88
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• 2009

This article suggests an online-based remote fault current mode discrimination method in order to identify the causes of the power line faults with various causes. For that, it refers to existing cause identification methods and categorizes modes by fault causes based on statistical techniques beforehand and performs the pre-treatment process of fault currents by each cause acquired from the fault recorder into a phase space in order to extract the characteristics of fault currents by each cause. After that, for the fault mode categorization, it discriminates modes by each cause using data by each cause as leaning data through utilizing RBF network. And then it tests the validity of the suggested method as applying it to the data of the actual fault currents acquired from the fault recorder in the electric power transmission center.

• Annals of Geriatric Medicine and Research
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• v.22 no.4
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• pp.189-193
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• 2018

Background: This study aimed to reveal the clinicopathologic features and causes of bleeding in older patients with postmenopausal bleeding (PMB) and to investigate the correlation between the ultrasonographic findings and etiology of PMB. Methods: We retrospectively analyzed the causes and clinical characteristics of PMB in 498 patients who were diagnosed between January 2007 and December 2017. The population with PMB was divided into 2 groups according to age: Group A (n=204) included individuals more than 65 years of age and group B (n=294) included those less than 65 years of age. Clinical characteristics such as age, parity, underlying conditions, previous surgical history, and previous menopausal hormone therapy were compared between the groups. Cervical cytology testing and transvaginal ultrasonography were performed in all patients with PMB. Endometrial biopsy was performed in all cases of endometrial thickness ${\geq}5mm$. Results: We examined 498 patients with PMB. In group A, atrophic endometrium (n=125, 61.27%) was the most common cause of PMB. Twenty-three patients had gynecological malignancy (cervical cancer: n=12, 5.88%; endometrial cancer: n=8, 3.42%; ovarian cancer: n=3, 1.46%), and 30 patients had benign gynecological disease (endometrial polyp: n=10, 4.90%; submucosal myoma: n=6, 2.94%; uterine prolapse: n=7, 3.42%; cervical dysplasia; n=5, 2.45%; cervical polyp: n=2, 0.98%). Forty patients had endometrial thickness ${\geq}5mm$. Eight patients were diagnosed with endometrial cancer. All cases of endometrial cancer were diagnosed with endometrial thickness >10 mm. Conclusion: Atrophic endometrium was the most common cause of PMB in both groups, and approximately 12% of cases were associated with gynecological malignancy in older patients.

• The Journal of Korean Medicine
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• v.42 no.2
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• pp.72-81
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• 2021

Objectives: We compared research characteristics of western medicine, Chinese medicine and Korean medicine on causes, mechanisms, types, treatments and prevention of psoriasis. Methods: For western medicine, "Psoriasis" was used as keyword on Pubmed, for Chinese medicine, "銀屑病" and "中医" on CNKI (China National Knowledge Infrastructure" and for Korean medicine, "건선" on OASIS. Keyword searches were done for papers and books published after 2010. For Chinese medicine, there were more in-depth searches done for "從血論 (血熱, 血瘀, 血燥)" and "陽虛症". Results: Western medicine puts an emphasis on the foci, and approaches it from molecular and genetic levels based on molecular biology; while it views psoriasis as a disease with multiple possible causes, it ultimately sees it as an inflammation that is immunity-mediated. Western medicine seeks to suppress cytokine in order to prevent and eliminate inflammation at each stage of treatment While they are effective short-term, psoriasis recurs shortly after. Chinese and Korean medicines categorize psoriasis as an internal comprehensive systemic diseases that encompasses the patient's physical and mental characteristics, and defines it as a disease that has many causes and mechanisms such as "血熱, 血瘀, 血燥" and "陽虛". They use herbal medicine, acupuncture, and lifestyle interventions to improve the overall health of the patient in addition to treating psoriasis. Treatments are effective, but it takes relatively longer to see results, and can recur. Conclusion: In order for more progress to happen on psoriasis treatment, each branch of medicine must exchange knowledge and information more frequently.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.113-116
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• 2004

In this study, the causes of temporal bright image sticking problem in an AC PDP were investigated. The temporal bright image sticking problem in an ac PDP is observed to be a relatively lower luminance following several minutes on-time at a high gray level compared to that of the ordinary turned-on image area. We focused on the detailed causes of image sticking, which are directly related with the visible emission such as the changes in the characteristics of phosphor, MgO surface and gas dynamics. The experimental results show that the thermal quenching of phosphor and temperature-dependent discharge characteristics change cause the image sticking problem.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.6
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• pp.42-48
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• 1999

Engine misfire causes of the negative effect on exhaust emission such as HC, CO, and NOX . Moreover, it causes damage to the three-way-catalyst(TWC) system permanently. The crankshaft velocity fluctuation(CVF) method has been applied for the real cars as misfire detection system usually, which utilizes the crank angle sensor input to calculate the variation of the crankshaft rotational speed. But this approach has the limit due to the fact that three could be problem under certain engine condition like as deceleration or high speed condition . Therefore the development of new methods are requested today. This study introduced the new method of misfire detection using breakdown voltage(BDV) characteristics between spark plug electrouds.

• Journal of Korean Society for Quality Management
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• v.37 no.1
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• pp.29-39
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• 2009

This article investigates economic-statistical design of VSSI(variable sampling size and interval) cause-selecting charts considering two assignable causes. We consider a process which is composed of two dependent sub-processes. In each sub-process, two kinds of assignable cause may exist. We propose a procedure for designing VSSI cause-selecting charts, based on Lorenzen and Vance model. Computational experiments show that the VSSI cause-selecting chart is superior to the FSSI cause-selecting chart in the economic-statistical characteristics, even under two assignable causes.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2472-2479
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• 2008

There exist several ways to analyse the accident causal analysis. Selection of a method and procedure depends on the characteristics of the system being analysed. Moreover, the selection should take into account of how the accidents causes are classified, since analysis model should make use of the classified causes to identify factors contributing to the risk of accidents. For railway case, a relational analysis as well as statistical estimation of significant hazard frequencies is applied to identify the dominant causes of accidents. This paper introduces outline of the causal analysis system, which is a significant part of the railway accident information and analysis system.

• Neonatal Medicine
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• v.28 no.3
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• pp.99-107
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• 2021

Purpose: Studies have been conducted on the prevalence and infant mortality rate of congenital anomalies; however, studies on child mortality are rare. Therefore, we evaluated the characteristics of deaths associated with congenital anomalies among children born in Korea who died within 5 years of age. Methods: Birth-to-death cohort linked data of children under the age of 5 years from 2010 to 2013, and statistical data on the cause of death by age from 1999 to 2019, both provided by the Korea National Statistical Office's Microdata Integrated Service, were retrospectively investigated. We investigated the trends and characteristics of mortality associated with congenital anomalies. Results: Among 1,858,945 children, 6,510 children who died were under 5 years of age, and among them, 1,229 deaths were associated with congenital anomalies, while 5,281 deaths were due to other causes. Deaths associated with congenital anomalies accounted for 18.9% of all deaths. When comparing congenital anomalies by systems, anomalies of the cardiovascular system (52.6%) were the most common. The mortality rate associated with congenital anomalies and those of other causes showed similar declining trends in 21 years. Conclusion: The mortality rate of congenital anomalies during the first 5 years of life did not increase differently from the prevalence of congenital anomalies but rather decreased. Deaths associated with congenital anomalies accounted for 20.5% of all infant deaths and 12.1% of child deaths, since the major causes of death in infants and children are slightly different, continuous and careful monitoring is required.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.1
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• pp.87-98
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• 2005

This research investigates economic-statistical characteristics of variable sampling size and interval (VSSI)$\bar{X}$charts under two assignable causes. A Markov chain approach is employed in order to calculate average run length (ARL) and average time to signal (ATS). Six transient states are derived by carefully defining the state. A steady state cost rate function is constructed based on Lorenzen and Vance(1986) model. The cost rate function is optimized with respect to six design parameters for designing the VSSI $\bar{X}$ charts. Computational experiments show that the VSSI $\bar{X}$ chart is superior to the Shewhart $\bar{X}$ chart in the economic-statistical sense, even under two assignable causes. A comparative study shows that the cost rate may increase up to almost 30% by overlooking the second cause. Critical input parameters are also derived from a sensitivity study and a few guideline graphs are provided for determining the design parameters.