• Journal of Communications and Networks
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• v.11 no.2
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• pp.122-133
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• 2009

As wireless spectrum resources become more scarce while some portions of frequency bands suffer from low utilization, the design of cognitive radio (CR) has recently been urged, which allows opportunistic usage of licensed bands for secondary users without interference with primary users. Spectrum sensing is fundamental for a secondary user to find a specific available spectrum hole. Cooperative spectrum sensing is more accurate and more widely used since it obtains helpful reports from nodes in different locations. However, if some nodes are compromised and report false sensing data to the fusion center on purpose, the accuracy of decisions made by the fusion center can be heavily impaired. Weighted sequential probability ratio test (WSPRT), based on a credit evaluation system to restrict damage caused by malicious nodes, was proposed to address such a spectrum sensing data falsification (SSDF) attack at the price of introducing four times more sampling numbers. In this paper, we propose two new schemes, named enhanced weighted sequential probability ratio test (EWSPRT) and enhanced weighted sequential zero/one test (EWSZOT), which are robust against SSDF attack. By incorporating a new weight module and a new test module, both schemes have much less sampling numbers than WSPRT. Simulation results show that when holding comparable error rates, the numbers of EWSPRT and EWSZOT are 40% and 75% lower than WSPRT, respectively. We also provide theoretical analysis models to support the performance improvement estimates of the new schemes.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.50.2-50.2
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• 2013

Galaxy clusters, the largest gravitationally bound systems, are an important means to place constraints on cosmological models. Moreover, they are excellent places to test galaxy evolution models in connection to the environments. To this day, massive clusters have been found unexpectedly at high redshfit (Kang & Im 2009, Durret et al. 2011, Tashikawa et al. 2012), and evolution of galaxies in cluster has not been fully understood. Finding galaxy cluster candidates at z > 1 in wide, deep imaging survey data will enable us to solve such issues of modern extragalactic astronomy. We report new candidates of galaxy clusters in the wide and deep survey fields, European Large Area ISO Survey North1(ELAIS-N1) and North2(ELAIS-N2) fields, covering sky area of $8.75deg^2$ and $4.85deg^2$ each. We also suggest a new useful colour-colour selection technique to separate 1 < z < 2 galaxies from low-z galaxies by combining multi-wavelength data from the UKIRT Infrared Deep Sky Survey Deep Extragalactic Survey (UKIDSS DXS, JK bands), Spitzer Wise-area InfraRed Extragalactic survey (SWIRE, Optical-Infrared bands), Canada France Hawaii Telescope (CFHT, z band) and Infrared Medium-deep Survey(IMS, J band).

• Animal Systematics, Evolution and Diversity
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• v.9 no.1
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• pp.35-50
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• 1993

The Korean byozoans belonging to the Smittinidae, collected at 15 localities from the South Sea during the period from 1969 to 1991, were studied taxonomically. They are found to consist of eleven species, including one new species, Parasmfttfna contraria sp. nov. Of remaining 10 species, following four are known to be new to the Korean fauna: Smittfna malleolus, Parasmittfna elongata, Parasmittina crosslandf and Smfttofdea t-eticulata. Up to now, it is known that the Korean Smittinidae comprises 21 recorded species, including 19 species found from the South Sea. Eleven species are dealt with in the present report, with presentation of keys to the species of each genus, and photographic illustrations for the new species and tliose new to the Korean fauna.

• Journal of Microbiology and Biotechnology
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• v.19 no.7
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• pp.675-680
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• 2009

There is considerable interest in the isolation of potent radical scavenging compounds from natural resources to treat diseases involving oxidative stress. In this report, four new fungal metabolites including one new bisdihydroanthracenone derivative (1, eurorubrin), two new seco-anthraquinone derivatives [3, 2-O-methyl-9-dehydroxyeurotinone and 4, 2-O-methyl-4-O-(${\alpha}$-D-ribofuranosyl)-9-dehydroxyeurotinone], and one new anthraquinone glycoside [6,3-O-(${\alpha}$-D-ribofuranosyl)-questin], were isolated and identified from Eurotium rubrum, an endophytic fungal strain that was isolated from the inner tissue of the stem of the marine mangrove plant Hibiscus tiliaceus. In addition, three known compounds including asperflavin (2), 2-0-methyleurotinone (5), and questin (7) were also isolated and identified. Their structures were elucidated on the basis of spectroscopic analysis. All of the isolated compounds were evaluated for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity.

• Journal of the Korean Institute of Rural Architecture
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• v.8 no.1
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• pp.17-24
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• 2006

The purpose of this study is to provide the systematic report and analysis about Apartment VE application in Design Phase. In this study, the method of VE application is classified into foure groups-changing materials, changing a method of construction, acceptance of new technology, and use of new device. The facts found in this study can be summarized as follows. Application rate of VE is highest in building circumference parts. The main reason would be that there are many applicable factors according to locations, types of work, etc. Parking lots also show similar results with the same reason. It means there are a lot of possibility to adapt value engineering in these steps during the work. So far application of value engineering has been so limited that just small changes of process or method have been tried. One reason is the lack of challenging and the other is some characteristics of construction work which is very difficult to fix after completion. In the future, it would be more efficient to apply new technology and new device in construction work. Though these attempts have been ignored in Korea so far, there are still lots of possibilities to be developed in value engineering.

• Journal of Periodontal and Implant Science
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• v.44 no.5
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• pp.259-264
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• 2014

Purpose: The aim of this case report is to present the longitudinal results of sinus grafting using a new demineralized bovine bone material (DBBM) in human cases. Methods: A patient with a resorbed maxilla was treated by maxillary sinus grafting using a new deproteinized bovine bone material. After a healing period of 6.5 months, three implants were placed and restored. The patient was periodically recalled and followed up for 5 years after restoration. Results: Twelve partially edentulous patients (average age, 55.7 years) were followed up. All patients had insufficient residual height in their maxillary posterior area and underwent maxillary sinus graft surgery to increase the height of their maxilla. In all, 27 fixtures were placed in the augmented bone area. On average, 8.6 months later, implants were loaded using provisional or final restorations. The observation period ranged from 27 to 75 months (average, 43.3 months), and the patients did not show any severe resorption of the graft material or any infection during this time. Conclusions: Our results show that the new DBBM is useful for a maxillary sinus graft procedure. Good healing responses as well as reliable results were obtained for an average follow-up period of 43.3 months.

• The Korean Journal of Zoology
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• v.2 no.1
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• pp.17-28
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• 1959

In Korea ,little attention was paid to chiggers until 1950 so only to reports on four species of chiggers were pulished before Korean War. Since 1950 (beginning of Korean War), a marked progress in the study of chiggers has been made in connection with investigations of Epidemic hemorrhagic fever occurring among the United Nations troops which was suspected as a chigger-borne infectious disease and the first report of tsutsugamushi disease in Korea called natives attention to chiggers as the vector mites of this newly known disease in Korea. This paper is mostly based on specimens of author's collections from 3269 Rodentia Insectivora, 9 Chiroptera, 24 Aves , 35 Amphibia and 3 Reptilia during the time from December 1955 to December 1956 but four species were introduced here from works of others . There are reported here five species of chiggers previously known only out of Korea and a new species also. This new species was collected by author but Lipovsky informed his colleague had collected the same one in Korea and they would publish it as new one in near future. This is the reason of describing the new species without specific name . Of course, this paper is incomplete in view of the geographic distribution, seosonal change and host relation etc, but will serve as a brief summary of the chiggers fauna of Korea up to the present. This species described here are as follows : Gahrliepia brennani var. ventralis Neoschongastia posekanyi Euschongastia kigtajimai Euschongastia miyagawai Euschongastia koreaensis Trombicula nagayoi Trombicula japonica Trombicula pomeranzevi Trombicula mitamurai Trombicula tamiyai Trombicula palpalis Trombicula orientalis Trombicula pallida Trombicula scutellaris Trobmicula miotis Trombicula hiranumai Trombicula sp. Trombicula hiranumai Trombicula sp. Trombicula subintermedius Shunsennia tarsalis . Euschongastia ikaoensis . Trombicula koomori Trombicul subakanushi

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.6
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• pp.814-820
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• 2000

Statement of Problem. Commonly used classification systems do not inform for dentists the dimension of the available bone at a potential implant site although regarding a variety of morphologic and pathophysiologic aspects using schematic graphs. However, for the implantologist the availability of bone substance is most important independent whether it concerns the jaw basis or the alveolus. Purpose of Study. The present article refers to a new evaluation form, to analyze the available bone with regard to optional immediate loading site by site. According to a new systematic implant planning concept will be presented in two case reports. Results. The feasibility of the classification for planning and documentation of immediately loaded implants is presented in two case reports. Conclusion. The factor of bone support for immediate functional stability is important in dental implantology. The new systematic implant planning helps to systematically estimate the dimension (ASCIi classification) of the alveolus site by site to evaluate the possibility of immediate loading. The Gottingen classification thus aids to determine the degree of stability that can be expected for the planned solution.

• Structural Engineering and Mechanics
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• v.6 no.1
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• pp.41-61
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• 1998

A state-of-the-art report on the new finite elements formulated by the addition of nonconforming displacement modes has been presented. The development of a series improved nonconforming finite elements for the analysis of plate and shell structures is described in the first part of this paper. These new plate and shell finite elements are established by the combined use of different improvement schemes such as; the addition of nonconforming modes, the reduced (or selective) integration, and the construction of the substitute shear strain fields. The improvement achieved may be attributable to the fact that the merits of these improvement techniques are merged into the formation of the new elements in a complementary manner. It is shown that the results obtained by the new elements give significantly improved solutions without any serious defects such as; the shear locking, spurious zero energy mode for the linear as well as nonlinear benchmark problems. Recent developments in the transition elements that have a variable number of mid-side nodes and can be effectively used in the adaptive mesh refinement are presented in the second part. Finally, the nonconforming transition flat shell elements with drilling degrees of freedom are also presented.

• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.414-424
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• 2010

This report describes recent advances in tissue culture, genetic transformation of commercial rose (Rosa hybrida) and in development of new rose cultivars by molecular breeding. Rose is one of major cut-flowers in global horticulture industry. Successful progresses were made in development of new cultivars for pathogen resistant, environmental stress resistant and petal color modification by molecular breeding. New cultivars, however, has not reported yet in korea, although lots of progresses were achieved in each field of conventional breeding, tissue culture and genetic transformation. Cooperation in these research fields will promote screening of useful genes to have specific traits on rose and exploiting of processes to improve in the efficiency of tissue culture and genetic transformation of rose, therefore, we hopefully expect that new rose cultivars by molecular breeding will be released in the near future.