• 전기학회논문지
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• 제59권6호
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• pp.1041-1045
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• 2010

Short-term electric load forecasting of power systems is essential for the power system stability and the efficient power system operation. An accurate load forecasting scheme improves the power system security and saves some economic losses in power system operations. Due to scarcity of the historical same type of holiday load data, most big electric load forecasting errors occur on load forecasting for the holidays. The fuzzy linear regression model has showed good accuracy for the load forecasting of the holidays. However, it is not good enough to forecast the load of the election day. The concept of the load variation rate for the load forecasting of the election day is introduced. The proposed algorithm shows its good accuracy in that the average percentage error for the short-term 24 hourly loads forecasting of the election days is 2.27%. The accuracy of the proposed 24 hourly loads forecasting of the election days is compared with the fuzzy linear regression method. The proposed method gives much better forecasting accuracy with overall average error of 2.27%, which improved about average error of 2% as compared to the fuzzy linear regression method.

• Earthquakes and Structures
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• 제14권4호
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• pp.305-312
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• 2018

Significant research efforts were undertaken to evaluate seismic performance of vertically irregular buildings on flat ground. However, there is scarcity of study on seismic performance of buildings on hill slopes. The present study attempts to investigate seismic behaviour of reinforced concrete irregular stepback building frames with different configurations on sloping ground. Based on extensive regression study of free vibration results of four hundred seventeen frames with varying ground slope, number of story and span number, a modification is proposed to the code based empirical fundamental time period estimation formula. The modification to the fundamental time period estimation formula is a simplified function of ground slope and a newly introduced equivalent height parameter to reflect the effect of stiffness and mass irregularity. The derived empirical formula is successfully validated with various combinations of slope and framing configurations of buildings. The correlation between the predicted and the actual time period obtained from the free vibration analysis results are in good agreement. The various statistical parameters e.g., the root mean square error, coefficient of determination, standard average error generally used for validation of such regression equations also ensure the prediction capability of the proposed empirical relation with reasonable accuracy.

• Journal of Yeungnam Medical Science
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• 제37권1호
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• pp.59-62
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• 2020

Hemoptysis is a major reason for emergency department (ED) visits. Catamenial hemoptysis (CH), a rare condition of thoracic endometriosis, can cause recurrent hemoptysis but is difficult to diagnose in the ED due to the scarcity of cases and nonspecific clinical findings. We report a case of a 26-year-old woman who presented to the ED with recurrent hemoptysis since 2 years without a definite cause. Her vital signs and blood test findings were unremarkable. Chest computed tomography (CT) did not show any specific lesions other than a non-specific ground-glass opacity pattern in her right lung. She was on day 4 of her menstrual cycle and her hemoptysis frequently occurred during menstruation. Although there was no histological confirmation, based on her history of hemoptysis during menstruation and no other cause of the hemoptysis, the patient was tentatively diagnosed with CH and was administered gonadotropin-releasing hormone. She had no recurrence of hemoptysis for 3 months. While CH is difficult to diagnose in the ED, the patient's recurrent hemoptysis related to menstruation was a clue to the presence of CH. Therefore, physicians should determine the relationship between hemoptysis and menstruation for women of childbearing age presenting with repeated hemoptysis without a definite cause.

• 한국콘텐츠학회논문지
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• 제16권2호
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• pp.618-632
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• 2016

드라마 제작산업의 가격결정 방식은 다중가격 체계를 형성하고 있다. 생산요소 가격은 방송사업자별, 제작주체별, 드라마 장르별로 차별화가 이루어지고 있다. 다중가격 체계에서 가격결정에 영향을 미치는 요인들은 생산요소의 희소성과 대체재의 유무, 제작비 규모, 명성 효과, 경쟁의 정도, 생산요소를 선택하는 주체 등이다. 스타 연기자에게 가격은 자신의 역량을 평가받는 기준으로 작용하는 동시에 자존심이라는 명성과 직결되는 기준으로 인식되고 있다. 이로 인해, 연기자 가격은 기존의 최고 가격을 경쟁자가 뛰어넘으며 경쟁하는 시소효과를 나타내고 있는 반면, 작가 가격은 최고 대우를 받고 있는 특정 작가의 가격 이하에서 제한적으로 상승하는 사다리 효과를 나타내고 있다. 현재는 제작비 규모의 상승 속도가 생산요소 가격의 상승 속도를 따라가지 못하는 상황이기 때문에 런닝개런티 제도를 적용하여 합리적인 시장 가격 형성을 위한 기준이 마련되어야 할 시점이다.

• Geomechanics and Engineering
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• 제15권2호
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• pp.729-738
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• 2018

Soft clay soils due to their various geotechnical problems, stabilized with different additives. Traditional additives such as cement and lime will not able to increase the soil strength properties significantly. So, it seems necessary to use new additives for increasing strength parameters of soft clay soils significantly. Among the new additives, epoxy resins have excellent physical and mechanical properties, low shrinkage, excellent resistance to chemicals and corrosive materials, etc. So, in this research, epoxy resin used for stabilization of soft clay soils. For comprehensive study, three clay soil samples with different PI and various clay mineral types were studied. A series of uniaxial tests, SEM and XRD analysis conducted on the samples. The results show that using epoxy resin increases the strength parameters such as UCS, elastic modulus and material toughness about 100 to 500 times which the increase was dependent on the type of clay minerals type in the soil. Also, In addition to water conservation, the best efficiency in the weakest and most sensitive soils is the prominent results of stabilization by epoxy resin which can be used in different climatic zones, especially in hot and dry and equatorial climate which will be faced with water scarcity.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2429-2435
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• 2012

Methyl isocyanate may have a role in cancer etiology, although the link is unclear. There is evidence in the literature that it can induce cancer in animals but the carcinogenic potency is weak. Pheochromocytoma of adrenal medulla and acinar cell tumors of pancreas have been observed in methyl isocyanate exposed animals. Conversely, emerging data from population-based epidemiological studies are contradictory since there is no evidence of such cancers in methyl isocyanate exposed humans. Recently, we reported a high prevalence of breast and lung cancers in such a population in Bhopal. In vitro findings appearing in the latest scientific literature suggest that genomic instability is caused by methyl isocyanate analogs in lung, colon, kidney, ovary epithelial cells, and that hepatocytes may undergo oncogenic transformation, have obvious implications. The conflicting information prompted us to present this update over the last three decades on methyl isocyanate-induced cancers after an extensive literature search using PubMed. While the pertinent literature remains limited, with a scarcity of strong laboratory analyses and field-epidemiological investigations, our succinct review of animal and human epidemiological data including in vitro evidences, should hopefully provide more insight to researchers, toxicologists, and public health professionals concerned with validation of the carcinogenicity of methyl isocyanate in humans.

• The Journal of Asian Finance, Economics and Business
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• 제5권3호
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• pp.113-119
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• 2018

Higher Education Institutions (HEIs) are place contributing to the intellectual advancement of the nation, quality human resource, and to a number of socio-economic improvements for society and organizations. Despite facilitators and staffs are the bare-bone of HEIs, there is a scarcity of research, both conceptual and empirical, focusing on their organizational citizenship behaviors (OCB). To attempt to fill this gap, this article develops a conceptual model of OCB under influencing of organizational justice and job satisfaction. The prospective respondents were chosen randomly from HEIs (public and private). Individuals have been employed at least one year and above will be the unit of analysis in which the experimental test of the proposed model will be conducted. The results suggest that organizational citizenship behavior is one of the most important factor influence the organizational performance. Furthermore, the performance of HEIs does not affect only the national human resources, but also impact on national economy. In this context, a conceptual framework is proposed to study the determinants of organizational citizenship behavior in the form of organizational justice and job satisfaction. Additionally, the ultimate benefits of OCB through perceived organizational justice with job satisfaction as mediator is enlightened. Finally, the authors discuss the managerial implications of their research.

• 한국항행학회논문지
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• 제12권2호
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• pp.132-138
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• 2008

최근 주파수 자원 부족 문제로 인하여 무선 인지(Cognitive Radio) 기술과 같은 주파수 공유 기술에 대한 연구가 활발히 진행 중에 있다. CR기술의 구현을 위해서는 주파수 대역의 사용 유무를 판단하는 스펙트럼 센싱기술의 구현이 우선시 된다. IEEE 802.22 WRAN은 CR 기술을 사용한 첫 번째 표준화로 TV대역에서의 인터넷 서비스를 목표로 하고 있다. 따라서 본 논문에서는 IEEE 802.22에 제시된 여러 센싱 기법들 중에서 협대역에서 ATSC신호를 검출하는 센싱 기법들인 에너지 검출기법, 스펙트럴 상관성 센싱 기법, 공분산을 이용한 센싱기법에 대하여 설명하고 오경보 확률이 10%일때의 미검출 확률을 통해서 성능을 분석하였다. 분석한 결과를 바탕으로 각각의 센싱 기법의 장단점을 보완할 수 있는 방법으로 에너지 검출 기법을 기반으로 하는 이중 센싱 구조를 제안하였고, 제안된 센싱구조를 실험을 통해 각각의 센싱 기법과 비교 분석하였다.

• 멤브레인
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• 제27권4호
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• pp.291-312
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• 2017

해수담수화는 최근 전 세계적으로 대두되고 있는 물부족 현상을 해결하기 위한 최적 기술 중 하나이다. 막분리 및 투과 현상의 근본적인 이해는 차후의 막여과 기술의 발전을 위해서 뿐만 아니라, 현재 막기술 증진을 위한 통합적 디자인, 최적화 제어법, 그리고 중장기적 유지관리를 위해서도 매우 중요하다. 이에, 본 연구는 물질 전달 및 여과 현상에 대한 기존의 주요 모델들을 상세히 재검토하고, 통계물리학에 근간하여 주요 막분리 현상들을 이론적으로 분석하며, 원천적 모델에 기초한 물리적 의미와 그들이 실제 막공정에서 미치는 영향들에 대해서 함축적으로 토의하고자 한다. 이론적 재검토의 과정에서 새로이 유도된 복합적 막오염도(Combined Fouling Index (CFI))의 소개도 포함한다.

• Journal of Forest and Environmental Science
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• 제34권1호
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• pp.24-30
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• 2018

In Botswana, mopane worms are widely harvested for household consumption. They are also traded for income generation. Urban based entrepreneurs' source mopane worms from rural areas to sell. The price of sourcing mopane worms from the harvesters has increased quite incredibly in villages. However, there is dearth of academic studies on the commercialisation of mopane worms in Botswana. This paper uses primary data collected from multiple sources to investigate the factors influencing the prices of mopane worms. Data collection involved administration of questionnaires to purposively selected harvesters in four campsites in the Central District, focus group discussions at each campsite and key informant interviews. The results show that there is declining population of mopane worms. The decline is attributable to such factors as over-harvesting and climate change which are the main factors influencing the price of mopane worms. In addition to physical scarcity of mopane worms, institutional weaknesses exist in the study area. The Agricultural Resources Conservation Act is ineffective and the majority of the harvesters are unaware of its existences. It is recommended that the regulations on the harvesting of mopane worms be reviewed. In order to benefit harvesters, mopane worms should be processed to add diversified economic value to rural communities.