• The Journal of Engineering Geology
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• v.23 no.3
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• pp.305-314
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• 2013

Recent international and national research trends in landslide hazards were analyzed by performing a literature search of relevant scientific journals. For obtaining data from Korea, we used 'Information for Environmental Geology' (IEG), which covers 17 journals in the field of environmental geology. A total of 54 articles related to landslide hazards were found in 5 journals published in the period 2000-2012. The most common topic was landslide prediction or susceptibility (29 articles), followed by landslide mechanisms. For international information, we analyzed 1,851 articles from the 'Web Of Science' published from 2003 to the present. Researchers in Italy have published the greatest number of papers in this field, while papers from Korea rank first in terms of the citation index.

• Science of Emotion and Sensibility
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• v.10 no.4
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• pp.555-569
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• 2007

Ubiquitous computing environment is the new surroundings, currently being realized by modern technology. Since previous usability tests are not suitable for this new technological environment, new research on psychological factors needs to be conducted. The evaluation of service scenarios also will be required in tandem with traditional usability tests of operation devices. Consequently, this study classified usability factors from a scenario perspective and was conducted with a focus on the psychological elements of controllability from a mechanical perspective. Study 1 reclassified the factors of existing usability tests according to similarity and application scenarios, and ten important groups of factors were newly created. Study 2 focused specifically on the design side of a device and showed that the degree of familiarity with the ubiquitous computing device and its complexity brought about a difference in perceived controllability of the device.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.308-308
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• 2009

유기농액비 자가제조 방법의 표준화를 위해 농가 현황조사를 통해 유기농액비 제조방법을 분류하고 제조 시기별 성분함량 변동상을 분석하였다. 조사대상 액비는 경기 9, 강원 5, 충북, 1, 충남 20, 전남 6, 경북 5, 경남 8 등 총 54종이었다. 자가제조 유기농액비에 사용된 재료는 감, 매실, 복숭아, 사과, 참다래, 토마토, 파프리카, 양파, 파, 인삼, 미나리, 민들레, 쇠비름, 쑥, 익모초, 산야초, 황기, 환삼덩굴, 으름열매, 은행과피, 배 어린 열매, 감껍질, 깻묵, 들깨대, 물미역, 쌀뜨물, 쌀겨, 꽁치, 바다생선 (잡어), 불가사리, 생선부산물(내장, 뼈 등), 액젓부산물(해산물의 뼈가 많이 함유된 물질), 동물뼈(돼지, 닭 등), 골분, 혈분, 천매암, 천일염, 계란껍질, 조개껍질, 게껍질, 새우껍질, 굴껍질, 농가부산물, 음식부산물, 구아노, 들깨 대 숯, 참깨 대 숯 등이었다. 제조방법은 기본재료+물, 기본재료+물+미생물, 기본재료+당밀, 기본재료+당밀+미생물, 기본재료+흑설탕, 기본재료+흑설탕+미생물 등이었다. 유기농액비의 화학적 특성은 다양하였으며, 혈분을 주 원료로 한 유기농액비의 화학성변화는 시간의 경과함에 따라 pH는 4.99에서 3.85로 낮아졌지만, EC, T-C, T-N, $P_2O_5$, $K_2O$, CaO, MgO, $Na_2O$, Fe, Mn, Zn 등은 높아졌다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.7
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• pp.555-561
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• 2014

Acoustic Emission technique is widely applied to develop the early fault detection system, and the problem about a signal processing method for AE signal is mainly focused on. In the signal processing method, envelope analysis is a useful method to evaluate the bearing problems and wavelet transform is a powerful method to detect faults occurred on rotating machinery. However, exact method for AE signal is not developed yet for the rotating machinery diagnosis. Therefore, in this paper two methods which are processed by Hilbert transform and DET for feature extraction. In addition, we evaluate the classification performance with varying the parameter from 2 to 15 for feature selection DET, 0.01 to 1.0 for the RBF kernel function of SVR, and the proposed algorithm achieved 94 % classification of averaged accuracy with the parameter of the RBF 0.08, 12 feature selection.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.10C
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• pp.981-990
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• 2006

In this paper, we introduce the concept of a subcarrier-based virtual multiple antennas (SV-MIMO) for OFDM cellular systems, where the multiple antenna techniques are performed on a set of subcarriers, not on the actual multiple antennas. The virtual multiple antenna system can support multiple users simultaneously as well as reduce inter-cell interference (ICI) form adjacent cells with a single antenna. Also, this technique is easily extended to multiple antenna environments. The virtual multiple antenna techniques can be divided into a virtual smart antenna technique and a virtual MIMO technique. Especially, this method effectively reduces ICI at cell boundary with frequency reuse factor equal to 1, and can support flexible resource allocation depending on the amount of interference. It is shown by simulation that the proposed method is superior to conventional method under the same condition of data transmission.

• Journal of Mushroom
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• v.18 no.1
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• pp.72-78
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• 2020

During the monitoring of fungal pests in 2016 and 2017, Acrodontium crateriforme, Naganishia friedmannii, Pestalotiopsis trachicarpicola, Penicillium wollemiicola, and Trichoderma thailandicum were isolated from indoor air, mushroom flies (Phytosciara flavipes), and media materials in the cultivation houses of oak wood mushroom (Lentinula edodes) located in Seocheon, Jangheung, Buyeo, and Yeoju, Korea. These fungal species were identified based on their morphological characteristics after their growth on PDA and subsequent molecular analyses of the 26S rDNA, 28S rDNA, β-tubulin gene, and translation elongation factor 1-α gene using PCR amplification and nucleotide sequencing were performed. The results showed that these fungi were previously undocumented in Korea. This study reports descriptions of their taxonomical and known properties.

• Journal of the Korean Society for Library and Information Science
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• v.46 no.4
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• pp.5-25
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• 2012

The purpose of this study is to develop a measurement tool for the quality of information commons. Information commons is a physical, technological, social, and intellectual place where library users can experience various educational, research, and cultural activities. It is recently gaining popularity and several libraries have implemented it to help users share knowledge and interact with each other. It also intends to provide a place for collaboration, learning, and rest. Despite its benefits and usefulness, there is no measurement tool explicitly designed for the quality of information commons. This study used in-depth personal interview, compared prior studies, and conducted a pilot study to elicit library users' perceptions on information commons and factors influencing on the perceived quality of information commons. Groups of initial items were emerged through classifying and clustering key concepts in the data. Then, the validity of the items were verified through a pilot study. The findings of this study will be useful for developing more reliable and valid survey measurement tool.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.1
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• pp.75-95
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• 2014

The purpose of this study was to propose the improvements for high quality of National Library of Korea (NLK) Subject Headings List which was developed as a subject access tool in 2002. For this study, literature review, case study for subject headings lists of national libraries, and data analysis of headings and relationships were performed. Several problems were found as follows: inconsistency of subject headings descriptions, unclear and unnecessary relationships among headings, inconsistency of hierarchical relationships, lack of currency, incorrectness of classification numbers, duplication of newly requested terms, and assignment of non-preferred and unregistered terms in bibliographic records. Focusing on these problems, modifications of subject headings and bibliographic records, installation and operation of an review committee on subject headings, and supplementation of a manual were suggested to improve NLK Subject Headings List.

• Journal of the korean Society of Automotive Engineers
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• v.6 no.2
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• pp.14-19
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• 1984

종래에 많이 사용된 각양의 계측 방법을 일일이 설명하는 것은 본 해설의 목적이 아니기 때문에 개략적으로 분류하여 설명하면 다음과 같다. 1) 시간 평균유속은 주로 프로브(probe)를 경유하여 동압과 정압의 측정에 의하여 수행되어 왔다. 연소반응이 있으면 밀도의 변화가 있게 되는데 밀도는 후술하는 농도의 계측과 온도의 계측에 의하여 정해져 동압과 정압으로부터 유속으로 변환된다. 시간분해능이 높은 비접촉식(직접 프 로브를 측정부에 삽입하지 않는 방법) 유속측정이 가능한 방법으로는 레이저 도플러 유속계 (Laser Doppler Velocimetry, 이하 LDV로 표현)를 들 수 있다. LDV는 압력측정에 의한 유속 산출법에서와 같은 온도 및 농도 등의 부수적인 계측이 필요없이, 직접 유속을 검출할 수 있으며 또한 검정이 필요없는 절대유속 측정이 가능하며 현재 연소반응이 있는 흐름에 대한 대부분의 연구에 적용되고 있는 실정이다. 2) 시간평균 화학종 농도측정에 가장 많이 쓰이는 방법은, 연소가스를 채취하여 가스 크로마토 그라프(Gas Chromatograph)로 분석하는 것을 들 수 있다. 한편, 시간 분해능이 높은 화학종 농 도의 계측은 레이저를 사용하여 각 화학종의 발광, 산란 및 흡수성을 이용, 측정한다. 3) 온도측정은 대부분 열전대를 사용하고 있다. 그러나 이 방법은 직접 프로브를 삽입해야 하므로 사용한계의 범위가 지극히 좁으며, 연소반응이 일어나므로 프로브 자체의 촉매반응 및 복사 열전달에 의한 보정 등이 사용상 큰 문제로 제기된다. 그러나 최근 레이저 이용기술의 발달로 (2)항에서의 농도 계측과 같이 반응기체의 온도 및 성분의 동시측정이 가능한 방법도 점차 현 실화 되어가고 있다. 그 대표적인 예로 CARS법(Coherent Anti-Stokes Raman Spectroscopy)을 들 수 있다. 이상으로부터 연소반응이 일어나는 흐름에서의 각종 계측에서는, 비접촉 측정의 가능성과 시간 공간 분해능의 특징으로 미루어 앞으로는 레이저를 이용한 계측 방법이 그 주류를 이룰 것으로 사료된다. 우선 본 해설은 기체의 온도 및 농도의 광학적 측정방법중 Raman산란광 검출법에 대하여 실제로 측정하는 입장에서 간단히 소개한다.

• Journal of Korean Society of Steel Construction
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• v.21 no.6
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• pp.563-574
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• 2009

This paper briefly describes the fundamental strategies--path-tracing, pin-pointing, and path-switching--in the computational elastic bifurcation theory of geometrically non-linear single-load-parameter conservative elastic spatial structures. The stability points in the non-linear elasticity may be classified into limit points and bifurcation points. For the limit points, the path tracing scheme that successively computes the regular equilibrium points on the equilibrium path, and the pinpointing scheme that precisely locates the singular equilibrium points were sufficient for the computational stability analysis. For the bifurcation points, however, a specific procedure for path-switching was also necessary to detect the branching paths to be traced in the post-buckling region. After the introduction, a general theory of elastic stability based on the energy concept was given. Then path tracing, an indirect method of detecting multiple bifurcation points, and path switching strategies were described. Next, some numerical examples of bifurcation analysis were carried out for a trussed stardome, and a pin-supported plane circular arch was described. Finally, concluding remarks were given.