• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.54-60
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• 2008

Sound absorption coefficients of oak (Quercus mongolica) wood and oak mushroom bed log were measured by the two microphone transfer function method and anatomical features of oak mushroom bed log examined by stereo scope and SEM observations. The sound absorption coefficients of oak mushroom bed log seemed to be higher than those of normal oak wood specimen over all estimated frequency range. Especially, in the frequency range of 2 to 6 kHz, they were about 2~3 times higher than those of normal wood specimen. Due to fungi degradation, the specific gravity of oak mushroom bed log decreased about 70% than that of normal wood. For oak mushroom bed log, abundant pores occurred on the radial, tangential and cross sectional surface and it was considered that the pores behaved as a sound absorbing pore.

• Applied Microscopy
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• v.3 no.1
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• pp.23-28
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• 1973

The changes of rough surfaced endoplasmic reticulum of plasma cells in the regional lymph node after injection of Bovine Gamma Globulin summarized as follow: The rough ER of plasma cells before antigenic stimulation shows flattened sac but changed to vesicular at 3rd day and vacuolar at 7th to 10th day. lntradisternal granules are appeared within the lumina or rough ER at 7th to 10th day. The rough ER is changed to distended sac or flattened sac at 20th day. The results suggest that normally flattened sac of rough ER is changed to vesicular and then to vacuolar after antigenic stimulation. But they are returned to distended sac or flattened sac with disappearance of antigenic stimuli.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.407-416
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• 2014

The purpose of this study is to identify the effect of physical environment on customer satisfaction and revisit intention. The questionnaire was distributed from October 1st to 31st, of the 250 distributed questionnaire 221 copies were used in the analysis to give a response rate of 88.4%. The results of the study were as followed; Firstly, it was found that perception of customers regarding physical environment of a buffet restaurant are cleanliness, entertainment, aesthetics, convenience and comfort. Secondly, it appeared that cleanliness of physical environment of buffet restaurant had the most influence on customer satisfaction. Thirdly, it also indicated that customer satisfaction had a influence on revisit intention. Based on these findings, this paper suggests implications and limitation of the research as well as future directions for the study.

• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.121-133
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• 2018

This study begins with focus on the public opinion and political views on embracing Yemeni refugees in Jeju. The public opinion is demanding amendment or even abolition of the Refugee Act. The argument opposing Yemeni refugees is persuasive enough in terms of public order and safety, cultural conflicts and economic interests, but it is going against the universal and authentic values that must be pursued by a forward-looking society. It is natural that the power exerting political discretion keeps an eye on public opinion. However, no matter how many people express it, unjustified public opinion must not be a foundation for political decision. This study will examine the shadows of public opinion and related concepts for those reasons, and review Augustine's concept of 'love' as a value to refer to in making a communal decision. Conflicts lead to insecurity and rift. Without sensus communis (common sense), the rift will not be healed. This study raises the need to resolve such conflicting state and seeks insight from Augustine.

• Korean Journal of Materials Research
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• v.7 no.8
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• pp.654-659
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• 1997

HMDS[Si$_{2}$(CH$_{3}$)$_{6}$]단일 선구체를 이용하여 화학증착 방법으로 성장된 3C-SiC/Si(001) 이종접합박막의 특성을 XRD, 라만 스펙트럼 및 투과전자현미경(TEM)등을 이용하여 조사하였으며 시판되고 있는 상용 3C-SiC/Si 시편을 같은 방법으로 분석하여 특성을 비교검토하였다. $C_{3}$H$_{8}$-SiH$_{4}$-H$_{2}$혼합가스를 선구체로 이용하여 5$\mu\textrm{m}$두께로 성장된 상용 3C-SiC/Si 이종접합박막 시료의 XRD스펙트럼에서는 강한 3C-SiC(002)피크 만이 관찰되었으며, 라만 스펙트럼의 LO피크는 970nm$^{-1}$ 정도에서 강하게 나타났다. TEM 관찰 결과 다수의 전위, 쌍정, 적층결함 및 APB와 같은 결정결함들이 3C-SiC/Si 계면 근처에 집중적으로 분포되어 있었으며 성장된 박막은 단결정임을 확인할 수 있었다. 선구체로 HMDS를 사용하여 0.3$\mu\textrm{m}$ 및 2$\mu\textrm{m}$ 두께로 성장시킨 3C-SiC/Si 박막 시료의 XRD 스펙트럼은 다소 완만한 3C-SiC(002) 피크와 함께 3C-SiC(111)피크가 관찰되었으며, TEM으로 확인한 결과 소경각 결정립들이 약 5˚-10˚ 정도 방위차를 가지고 성장하여 기둥구조(columnar structure)를 이루고 있기 때문임을 알 수 있었다. 라만 스펙트럼 분석 결과 박막의 LO 피크가 967-969nm$^{-1}$정도로 다소 낮은 wavenumber쪽으로 이동되어 박막 내에 상당한 응력이 존재함을 확인할 수 있었다. 이와 같은 HMDS 3C-SiC박막의 특성은 성장 온도가 낮고 박막 성장용 가스로 사용한 HMDS 선구체에서 탄소가 과잉으로 공급되기 때문으로 제안되었다.다.

• Journal of the Korean Geosynthetics Society
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• v.15 no.1
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• pp.37-46
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• 2016

Rotary pile consists a single or multiple helix plate and it is installed into the ground using the rotation of the helix plate. Rotary pile in soft ground is able to be supported by pile shaft and helix plate. When the pile is installed into hard layer relatively, the end bearing capacity is possible to be increased by the lower helix plate. In this paper, small-size rotary piles were manufactured with using steel pipe which is reduced to 1/5 size of the rotary pile on the construction field. Pile load test was carried out on the foundation soil which was formed by weathered soft soil. The bearing capacity of small-scale piles depends on the number of helix plate, the length of plate diameter, and an interval of plates, respectively. The bearing capacity of pile increases about 40% with 3 helix plate and it is also confirmed that the bearing capacity is improved about 10% as the increment of plate interval.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.61-68
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• 2010

The objective of this study was to test the estimation possibility of driver's stress degrees with the HRV analysis. For this, first, HRV analysis was applied to the 5 driver's ECG signals which were acquired in 7 different stress situations. From this, the facts that HRV trend was different from that in long-distance driving and 6 parameters - meanRR, sdRR, HF, LF/HF, LFnorm, HFnorm were useful for the stress estimation in stress varying driving situation. Next, we designed 5 personalized linear regression models in which 6 HRV parameters were input and the outcomes were 7 different stress degrees. Finally, we tested each model for 5min-long 16 segments individually. Consequently, the models could not hit the stress degrees exactly in some segments but the correlation coefficients between original stress pattern and estimated stress pattern during entire driving showed reasonably high.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.6
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• pp.397-405
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• 2014

Software-Defined Networking (SDN), which separates the control plane from the data plane and manages data planes in a centralized way, is now considered as a future networking technology, and many researchers and practitioners have dived into this area to devise new network applications, such new routing methods. Likewise, network security applications could be redesigned with SDN, and some pioneers have proposed several interesting network security applications with SDN. However, most approaches have just reimplemented some well-known network security applications, although SDN provides many interesting features, They didn't effectively use them. To investigate if we can use SDN in realizing sophisticated network security applications, we have designed and implemented an advanced network security application, Reflectornet, which redirects malicious or suspicious network trials to other security monitoring points (e.g., honeypot). In addition, we have tested its performance and practicability in diverse angles. Our findings and some insights will encourage other researchers to design better or intelligent network security applications with SDN.

• Journal of Internet Computing and Services
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• v.12 no.2
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• pp.63-73
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• 2011

In general, conventional search engines provide the same search results for the same queries of users, and however such techniques do not consider users' characteristics. To overcome this problem, we need a new way of personalized search which returns customized search results according to users' preference. In this paper, we propose a concept network profile-based personalized web search system in which the concept network is developed for accumulating users' characteristics. The concept network-based user profile is used to expand initial search queries to achieve personalized search. The concept network is a network structure of concepts where each concept is generated whenever each query is submitted, and it can be defined as a set of keywords extracted from the selected documents. Furthermore, we have improved the concept networks by augmenting intent keywords of each concept with a set of classification tags, called folksonomy, assigned to each document. For an additional personalized search technique, we propose a new re-ranking method that analayzes the degree of overlapped search results.

• Journal of Ginseng Research
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• v.26 no.4
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• pp.213-218
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• 2002

Crystalline calcium oxalate occur throughout near)y all plants species in five major forms; styloids, druses, raphids, prisms and sands. These crystals are known to be distributed in specific tissue such as cortex, xylem, phloem, cambium and epidermis. This research was undertaken to identify the occurrence, type, location and ultrastructure of druse crystals in Panax ginseng. In situ visualization, conventional light microscopy, histochemistry and scanning electron microscopy were applied for these purposes. Druse crystals in ginseng were identified as calcium oxalate by silver nitraterubeanic acid histochemistry. Calcium oxalate crystals are observed in nearly all plant organs such as leaf, petiole, peduncle, stem, rhizome, tap root and lateral root except fine root. Most frequent observation of crystals in the leaf and rhizomes were noticed. Three different types of calcium of oxalate druse crystals were identified by scanning electron microscopy.