• 제어로봇시스템학회논문지
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• 제19권9호
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• pp.846-852
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• 2013

In this paper, the authors propose a new approach to control problem of the marine vessels which are moored or controlled by actuators. The vessel control problem in the specified area is called a DPS (Dynamic Positioning System). The main objective of this paper is to obtain more useful control design method for DPS. In this problem, a complicate fact is control allocation which is a numerical method for distributing the control signal to the controlled system. For this, many results have been given and verified by other researchers using two individual processes. It means that the controller design and control allocation design process are carried out individually. In this paper, the authors give more sophisticated design solution on this issue. In which the controller design and control allocation problem are unified by a robust controller design problem. In other word, the stability of the closed-loop system, control performance and allocation problem are unified by an LMI (Linear Matrix Inequality) constraint based on $H_2/H_{\infty}$ mixed design framework. The usefulness of proposed approach is verified by simulation with a supply vessel model and found works well.

• 한국응용곤충학회지
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• 제53권4호
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• pp.465-472
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• 2014

담배가루이(Bemisia tabaci)는 바이러스 매개 역할과 함께 참외에 심각한 경제적 피해를 주고 있다. 담배가루이는 기주 작물과 농약 감수성 정도에 따라 다양한 생태형으로 분류되고 있다. 본 연구는 안동시 풍천면에 소재한 참외밭에서 성충을 채집하여 PCR 분자진단기법으로 동정하였다. 전체 11 곳의 채집 장소에서 Q 생태형 담배가루이를 진단하였고, 이 가운데 4 곳의 채집 장소에서 B 생태형도 검출되었다. 이러한 결과는 경북지역 참외 재배지에서 담배가루이가 발생한다는 최초의 보고이며, 특히 두 생태형이 동일한 재배지에 혼재한다는 것을 나타낸다.

• 한국보건간호학회지
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• 제34권3호
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• pp.391-404
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• 2020

Purpose: This study investigates the disaster preparedness behaviors of people residing in disaster areas and the factors affecting such behaviors, by examining the application of a Health Belief Model. Methods: A mixed-method approach was used for this study. Local residents were surveyed in Gyeongju and Pohang, which had experienced earthquakes one to two years earlier. Quantitative data (N=233) were collected through a questionnaire and analyzed using t-test, one-way ANOVA, Scheffe test and multiple regression. Qualitative data (N=11) were collected through focus group and individual interviews, and evaluated through content analysis. Results: Disaster preparedness behaviors scored 7.04 out of 18 points, and factors that significantly affected disaster preparedness included cut to action, marriage status, experience of education and training related to disaster, benefit-barriers factors of disaster preparedness behaviors, and gender. The focus group and individual interviews confirmed the contents corresponding to each variable of the disaster preparedness behaviors and heal belief model. Conclusion: The findings of this study indicate that in order to induce disaster preparedness behaviors as well as education and training opportunities related to disaster relief, we need to examine cue to action of disaster preparedness behaviors, benefits, and barriers for motivating interventions.

• 가정과삶의질연구
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• 제33권2호
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• pp.35-51
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• 2015

The purpose of this study was to provide information for research about residents' opinion toward the physical environments of elderly facilities, through the analysis and investigation on the research methodology of foreign academic journal articles from 1990 to 2014. The study results were as follows: Firstly, purposive sampling was a large majority of both facilities and elderly residents. In quantitative studies, many researchers have conducted simple random, cluster, or stratified sampling. Diverse facilities in area, size, location, and etc. should be considered for participation. The qualifications for residents' participation should be considered as well, so that they all could have autonomy for study participation. Secondly, questionnaire and semi-structured guide were likely to be used in independent and resident care facilities. On the other hand in assisted living and long-term care facilities, open questions and visual material were used as well. A compatible scale should be developed so that elderly having variable functional level could participate independently in the study. Thirdly, in data collection process, compliance with research ethics and well trained interviewer's skill were important for residents' active responses and minimization of response errors. Enough research period of time and mixed study in data collection will decrease the response error.

• Ocean and Polar Research
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• 제34권2호
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• pp.111-123
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• 2012

To understand the phytoplankton community in the eastern part of the Yellow Sea (EYS), in the summer, field survey was conducted at 25 stations in June 2009, and water samples were analyzed using a epifluorescence microscopy, flow cytometry and HPLC method. The EYS could be divided into four areas by a cluster analysis, using phytoplankton group abundances: coastal mixing area, Anma-do area, transition water, and the central Yellow Sea. In the coastal mixing area, water column was well mixed vertically, and phytoplankton was dominated by diatoms, chrysophytes, dinoflagellates and nanoflagellates, showing high abundance ($>10^5\;cells\;l^{-1}$). In Anma-do coastal waters characterized by high dominance of dinoflagellates, high phytoplankton abundance and biomass separated from other coastal mixing area. The southeastern upwelling area was expanded from Jin-do to Heuksan-do, by a tidal mixing and coastal upwelling in the southern area of Manjae-do, and phytoplankton was dominated by benthic diatoms, nanoflagellates and Synechococcus group in this area. Phytoplankton abundance and biomass dominated by pico- and nanophytoplankton were low values in the transition waters and the central Yellow Sea. In the surface of the central Yellow Sea, high dominance of photosynthetic pigments, 19'-hexanoyloxyfucoxanthin and zeaxanthin implies that haptophytes and cyanobacteria could be the dominant group during the summer. These results indicate that the phytoplankton communities in the EYS were significantly affected by the formation of tidal front, thermal stratification, and coastal upwelling showing the differences of physical and chemical characteristics during the summer.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권5호
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• pp.484-487
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• 2010

Cemento-ossifying fibroma is a true osteogenic neoplasm. It is also called as ossifying fibroma or cementify-ing fibroma. Small lesions seldom cause any symptoms and are detected only on radiographic examination. Large lesions result in a painless swelling of the involved bone. In radiographic features the lesion most often is well defined and unilocular. It may appear completely radiolucent, or more often varying degrees of rdiopacity. It is composed of fibrous tissue that contains a variable mixture of bony trabeculae,cementum-like spherules, or both. Treatment of most lesions generally is enucleation of tumor. However, some lesions which have grown large and destroyed considerable bone, may necessitate surgical resection and bone grafting. This case was the bony lesion that was found by accident in patient with mandibular left body and subcondylar fracture. In radiographic examination, there was a mixed radiolucent and radiopaque lesion in mandibular left body area with fracture line. We treated on mandibular left body and subcondylar fracture and enucleated the lesion on the left body area simultaneously. At surgical exploration, the lesion was well demarcated from the surrounding bone, thus permitting relatively easy separation of the tumor from its bony bed. In histopathologic examination, the lesion contained bony trabeculae and cementum-like spherules within a background of cellular fibrous connective tissue. It finally diagnosed as cemento-ossify-ing fibroma from the result of biopsy.

• Journal of Ecology and Environment
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• 제35권2호
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• pp.123-129
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• 2012

Salt marsh is an important transitional zone among terrestrial, riverine, and marine ecosystems and is a productive habitat that interacts extensively with adjacent landscape elements of estuarine and coastal ecosystems. Nowadays, in addition to various human activities, a variety of natural processes induce changes in salt marshes. This study aims to provide background information to restore disturbed salt marshes and to propose their ecological restoration using seed banks. The study area is a prepared area for the Gwangyang Container Port located in the southern Korea. This area was formed by accumulating mud soils dredged from the bottom of the forward sea. This land was created in a serial process of preparing the Gwangyang container port and the salt marsh was passively restored by seeds buried in mud soil dredged from seabed. As a result of stand ordination based on vegetation data collected from the land, stands were arranged according to tolerance to salinity in the order of $Suaeda$ $maritima$, $Salicornia$ $europaea$, and $Phragmites$ $communis$ communities on the Axis 1. Landscape structure of the projected area was analyzed as well. Edges of the projected area were divided from the marginal waterway by the dike. Four types of vegetation appeared on the dike: $Alnus$ $firma$ plantation, $Robinia$ $pseudoacacia$ plantation, $Lespedeza$ $cyrtobotrya$ plantation, and grassland. In the more internal areas, two types of vegetation sequences appeared: $Aster$ $tripolium$ community-$Suaeda$ $glauca$ community-$Salicornia$ $europaea$ community sequence and $Aster$ $tripolium$ community-$Suaeda$ $maritima$ community-$S.$ $europaea$ community sequence. Mixed community showed the highest species diversity (H' = 0.86) and $S.$ $europaea$ community showed the lowest (H' = 0.0). Evenness is the highest in Mixed community (J' = 2.26) and the lowest in $S.$ $maritime-S.$ $europaea$ community (J' = 0.0). Several plant communities were successfully established on the land created by mud soil dredged from the bottom of Gwangyang Bay. Moreover, community diversity in this area approached a similar level with those from other studies involving natural salt marshes. Therefore, restoration effect based on community diversity obtained in our study can be evaluated as a successful achievement. In this respect, although most salt marshes in Korea and other places worldwide have been destroyed or disturbed by excessive land use, feasibility of seed bank as a restoration tool is greatly expected.

• 대한원격탐사학회지
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• 제38권6_1호
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• pp.1035-1046
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• 2022

이 연구에서는 토지 피복 분류를 위한 다중 해상도 자료 융합의 적용성을 평가하였다. 여기서 다중 해상도 자료 융합 모델로는 spatial time-series geostatistical deconvolution/fusion model (STGDFM)을 적용하였다. 연구 지역은 미국 Iowa 주의 일부 농경 지역으로 선정하였으며, 대상 지역의 규모를 고려해 다중 해상도 자료 융합의 입력 자료로 Moderate Resolution Imaging Spectroradiometer (MODIS) 및 Landsat 영상을 사용하였다. 이를 바탕으로 STGDFM 적용해 Landsat 영상이 결측된 시기에서 가상의 Landsat 영상을 생성하였다. 그리고 획득한 Landsat 영상과 함께 STGDFM의 융합 결과를 입력 자료로 사용해 토지 피복 분류를 수행하였다. 특히 다중 해상도 자료 융합의 적용성 평가를 위해 획득한 Landsat 영상만을 이용한 분류 결과와 Landsat 영상 및 융합 결과를 모두 이용한 분류 결과를 비교 평가하였다. 그 결과, Landsat 영상만을 이용한 분류 결과에서는 대상 지역의 주요 토지 피복인 옥수수와 콩 재배지에서 혼재 양상이 두드러지게 나타났다. 또한 건초 및 곡물 지역과 초지 지역 등 식생 피복 간의 혼재 양상도 큰 것으로 나타났다. 반면 Landsat 영상 및 융합 결과를 이용한 분류 결과에서는 옥수수와 콩 재배지의 혼재 양상과 식생 피복 간의 혼재 양상이 크게 완화되었다. 이러한 영향으로 Landsat 영상 및 융합 결과를 이용한 분류 결과에서 분류 정확도가 약 20%p 향상되었다. 이는 STGDFM을 통해 MODIS 영상이 갖는 시계열 분광 정보를 융합 결과에 반영하면서 Landsat 영상의 결측을 보완할 수 있었고, 이러한 시계열 분광 정보가 분류 과정에 결합되면서 오분류를 크게 줄일 수 있었던 것으로 판단된다. 본 연구 결과를 통해 토지 피복 분류에 다중 해상도 자료 융합이 효과적으로 적용될 수 있음을 확인하였다.

• Journal of Communications and Networks
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• 제18권5호
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• pp.744-761
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• 2016

For about the past decade and a half research efforts into cognitive radio networks (CRNs) have increased dramatically. This is because CRN is recognized as a technology that has the potential to squeeze the most out of the existing spectrum and hence virtually increase the effective capacity of a wireless communication system. The resulting increased capacity is still a limited resource and its optimal allocation is a critical requirement in order to realize its full benefits. Allocating these additional resources to the secondary users (SUs) in a CRN is an extremely challenging task and integer programming based optimization tools have to be employed to achieve the goals which include, among several aspects, increasing SUs throughput without interfering with the activities of primary users. The theory of the optimization tools that can be used for resource allocations (RA) in CRN have been well established in the literature; convex programming is one of them, in fact the major one. However when it comes to application and implementation, it is noticed that the practical problems do not fit exactly into the format of well established tools and researchers have to apply approximations of different forms to assist in the process. In this survey paper, the optimization tools that have been applied to RA in CRNs are reviewed. In some instances the limitations of techniques used are pointed out and creative tools developed by researchers to solve the problems are identified. Some ideas of tools to be considered by researchers are suggested, and direction for future research in this area in order to improve on the existing tools are presented.

• 인문언어
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• 제2권1호
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• pp.93-127
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• 2002

This paper deals with a class of Middle English impersonal constructions that involve verbs of two-place argument structure. As is generally understood, the term 'impersonal' is notoriously murky, and after all those researches that have been performed in this area, quite a few issues still remain controversial. The issues we center around in the present study concern the following two. In the type of impersonal constructions we consider, the two arguments-Cause and Experiencer-are both expressed in oblique case, posing the problem of determining which of them functions as the grammatical subject. The issue, however. is not how an argument in oblique case can be taken as the subject: it is well blown that the so called 'dative subject Experiencer' already occurred in Old English. The real issue is why both of the arguments are syntactically realized as nonnominative. The other issue concerns the 3rd-person singular form of the verb. Here again, the crux of the problem may be blurred by the fact that impersonal construction is often defined as one in which the verb has 3rd-person singular form with no apparent nominative W controlling verb concord. But this definition is more nebulous than clear because the notion 'subjectless' is itself highly controversial. Thus, for an expression like me thinketh that-S, it may well be that the verb thinketh ('seems') is 3rd-person singular because the that-clause is the subject. What should be explained of the data brought up here is why the impersonal verb is 3rd-person singular when neither of the NPs associated with it is 3rd person or singular. I argue that we can account for our paradigm examples by looking upon them as 'mixed construction' in which semantic interpretation conflicts with syntactic parsing as a result of case syncretism and gradual establishment of SVO word order. This amounts to saying that the peculiarities of the construction originate with the confused use of impersonal verbs between the sense of 'give an impression' and that of 'receive and impression.'