• Spatial Information Research
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• v.22 no.4
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• pp.67-76
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• 2014

Recently, through the development of IT and mobile technology, spatial information plays a role of infrastructure of the people life and the national economy. Many kinds of applications including SNS and social commerce is to leverage the spatial information for their services. In the case of domestic, spatial open platform that can provide national spatial data infrastructure services in a stable manner has been released. And many people have been interested to the open platform services. However, the open platform currently has many difficulties to analyze its service status and load in real time, because it does not hold a real-time monitoring system. Therefore, we propose a method that can analyze the real-time service status of the open platform using the analysis of the web server log information. In particular, we propose the results of the analysis as follows: amount of data transferred, network bandwidth, number of visitors, hit count, contents usage, and connection path. We think the results presented in this study is insufficient to understand the perfect service status of the open platform. However, it is expected to be utilized as the basic data for understanding of the service status and for system expansion of the open platform, every year.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.204-215
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• 2020

We analyze changes of consumption behavior for bundle services for the latest three years focusing on comparing the detailed service types and service providers to understand competition structure in the market. Our major findings and implications are as follows. First, the mobile telecommunication service is certainly deemed to be a major selection criteria for bundling service provider, therefore the leading company in the mobile telecommunication has become more significant market power. Second, IPTV has an important influence for slection of bundling service provider, lately in some cases, rather than broadband Internet. Third, the individual services affecting the selection of bundling service providers clearly showed differentiation among three operators as a mobile telecommunication service of SK Group, a broadband Internet of KT, and an IPTV of LGU+. In addition, the importance of individual services in securing subscribers has been increased as the preference factors to switch a service provider were synchronized with the decision of major bundling service provider. Finally, although it is difficult to find customers' lock-In due to the latest change of their intentions to switch a provider, we find it is continuously necessary to monitor customers' lock-in as there are more long-term customers with re-contracts. Our results provide the policy implications based on the change of competition structure and usage behavior in the bundle market which is not evaluated the competiton situation.

• The Journal of the Korea Contents Association
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• v.20 no.4
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• pp.396-405
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• 2020

In this study, we used the big data of Voice of Customer (VOC) related to high-speed Internet products to look at the causes of perceived quality and the possibility of proactive service. In order to verify the possibility of proactive service, we collected VOC data from 13 facilities and equipment of a mobile communication service company, and then conducted 𝒙² test to verify that there was a statistically significant difference between the actual VOC observation values and expected values. We found statistical evidence that proactive service is possible through real-time monitoring for the six disability alarms among the 13 facilities and equipment, which are FTTH-R Equipment ON/OFF, FTTH-EV Line Error Detection, Port Faulty, FTTH-R Line Error Detection, Network Loop Detection, and Abnormal Limiting Traffic. Companies are able to adopt the proactive service to improve their market share and to reduce customer service costs. The results of this study are expected to contribute to the actual application of industry in that it has diagnosed the possibility of proactive service in the telecommunication service sector and further suggested suggestions on how to provide effective proactive service.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.207-214
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• 2017

There is little information about the seed longevity of wild plants, although seed bank storage is an important tool for biodiversity conservation. This study was conducted to predict the seed viability equation of Agastache rugosa. The A. rugosa seeds were stored at moisture contents ranging from 2.7 to 12.5%, and temperatures between 10 and $50^{\circ}C$. Viability data were fitted to the seed viability equation in a one step and two step approach. The A. rugosa seeds showed orthodox seed storage behaviour. The viability constants were $K_E=6.9297$, $C_W=4.2551$ $C_H=0.0329$, and $C_Q=0.00048$. The P85 of A. rugosa seeds was predicted to 152 years under standard seed bank conditions. The P85 predicted by seed viability equation can be used as basic information for optimization of seed storage processes.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.6
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• pp.43-54
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• 2016

The occurrence of cyber crime is on the rise every year, and the security control center, which should play a crucial role in monitoring and early response against the cyber attacks targeting various information systems, its importance has increased accordingly. Every endeavors to prevent cyber attacks is being attempted by information security personnel of government and financial sector's security control center, threat response Center, cyber terror response center, Cert Team, SOC(Security Operator Center) and else. The ordinary method to monitor cyber attacks consists of utilizing the security system or the network security device. It is anticipated, however, to be insufficient since this is simply one dimensional way of monitoring them based on signatures. There has been considerable improvement of the security control system and researchers also have conducted a number of studies on monitoring methods to prevent threats to security. In accordance with the environment changes from ESM to SIEM, the security control system is able to be provided with more input data as well as generate the correlation analysis which integrates the processed data, by extraction and parsing, into the potential scenarios of attack or threat. This article shows case studies how to detect the threat to security in effective ways, from the initial phase of the security control system to current SIEM circumstances. Furthermore, scenarios based security control systems rather than simple monitoring is introduced, and finally methods of producing the correlation analysis and its verification methods are presented. It is expected that this result contributes to the development of cyber attack monitoring system in other security centers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1B
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• pp.71-78
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• 2012

The habitat suitability is an important factor to estimate the distribution and size of the physical habitat in river. This suitability is also a key factor to decide the ecological flow discharge for the fish. For the ecological analysis in river, accurate values of habitat suitability index for various fishes are necessary. In general, fish habitat is affected by the physical factor of the flow depth and velocity as well as the chemical and biological factors of nutrient and attached algae. Thus, the condition of the fish habitat is expected to be changed with each watershed and tributary. In this study, the habitat suitability indices for fishes were proposed by using the field monitoring data in the rivers of the Han and Geum river watersheds. The proposed indices for three fishes are compared: Zacco platypus, Zacco temminckii, and Coreoleuciscus splendidus. The results show that Zacco platypus has a similar distribution of habitat suitability index in two watersheds. Zacco temminckii and Coreoleuciscus splendidus, however, have different distributions with watersheds. Also, for Zacco platypus, the developed indices at three tributaries of the Han river are compared: Cheng-mi stream, Dal stream, and Hong-cheon stream. The comparision shows that the index in the Cheng-mi stream is different with those in the other rivers. This is expected to be because of a high nutrient concentration at the Cheong-mi stream.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.240-248
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• 1997

References on the cooking and processing losses of organophosphorus (OP) pesticides in foods were collected and analyzed to indicate that the average removal of whole pesticides being 45% in water washing, 56% in detergent washing, 91% in peeling of fruits, 5l% in blanching-boiling of vegetables, 90% in milling and processing of grains. The theoretical maximum daily intake (TMDI) calculated from the food intake and Korea maximum residue limits showed that 4 among 11 pesticides exceeded the acceptable daily intake (ADI). The estimated daily intake (EDI) calculated from the food intake and monitoring data reached 17.2% of ADI on the assumption that the toxicity of OP pesticides appears as an additive effect. The % ratio of ADI for individual pesticides was 6.1% in diazinon, 5.8% in fenthion, 3.3% in fenitrothion and very low in other pesticides. By applying reduction factors to the EDI, the removal ratio of OP pesticides in cooking and processing appears to be over 50%. In summary, the exposure level of Korean population toward whole OP pesticides was estimated to reach 23% of ADI, which would not cause any health rick as yet, but calls for a systematic risk assessment.

• Science of Emotion and Sensibility
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• v.13 no.3
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• pp.467-474
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• 2010

Recently, Study of functional clothing for Vital sensing is focused on reducing artifact by human motions, in order to enhance the electrocardiogram(ECG) sensing accuracy. In this study, considering the factors for each element found from the analysis, a 3-lead electrode inside textile embroidered with silver yarn was developed, and draft designs off our types of vital-signal sensing garments, which are 'chest-belt typed' garment, 'cross-typed' garment 'x-typed' garment and 'curved x-typed' garment, were prepared. The draft designs were implemented on a sleeveless male shirt made of an elastic material so that the garment and the electrodes can remain closely attached along the contour of the human body, and the acquired data was sent to the main computer over a wireless network. In order to evaluate the effects caused by body movements and the ECG-sensing capability for each type in static and dynamic states, displacements were measured from one and two dimensional perspectives. ECG measurement evaluation was also performed for Signal-to-noise ratio(SNR) analysis. Applying the experimental results, the draft garment designs were modified and complemented to produce two types of modular approaches 'continuous-attached' and 'insertion-detached' for the ECG-sensing smart clothing.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1991.04a
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• pp.75-79
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• 1991

고도로 산업화가 진행됨에 따라 회전기계는 더욱 중요시되고 있으며 이의 성능 향상에 부단한 노력이 경주되고 있다. 특히 우주 시대의 개막과 더불어 우주선 및 인공위성에 사용하기 위해 초소형이며 초고속의 고성능회전모타 를 개발하기에 이르렀다. 한 예로서 미국립항공우주국(NASA)의 스페이스셔 틀에 사용되는 주엔진 터보펌프를 들 수 있는데 이 터보펌프는 접시만한 크 기로써 71000마력을 생성해 낸다. 이러한 가공할 만한 에너지 밀도와 유량을 감당해 내려면 종래의 회전기계보다는 훨씬 더 높은 회전속도를 가져야 한 다. 이러한 회전체는 큰 관성부하와 진 동 및 동안정성의 문제등을 내포하고 있다. 고성능 회전기계의 또다른 예로서 초정밀 가공용 공작기계를 들 수 있 다. 선반 혹은 밀링머신으로 초정밀가공을 행하기 위해서는 회전축의 진동이 극히 작아야 한다. 이와 같이 오늘날 갈수록 초고성능 초정밀도를 추구함에 있어서 회전축의 진동을 현장에서 모니터링하고 이 진동데이터를 분석하여 회전축을 제어하는 것이 강력히 요구되어진다. 따라서 in-situ 측정이 중요성 을 띠게 되었는데 이는 제어기술의 바탕이 되는 자료를 현장에서 제공할 수 있기 때문이다. 회전축 진동측정의 대상이 되는 것들은 모타, 발전기, 엔진 및 터빈등을 대표적으로 들 수가 있다. 여기서 소형회전기계의 축표면과 같 이 비교적 곡면을 이루고 있는 부분의 진동변위 측정에 신중한 고려가 요구 되어 진다. 이는 축의 곡면도에 따라 감도가 변화하기 때문이다. 따라서 평 판에 대한 calibration 챠트를 회전기계축진동 변위환상에 이용하면 곡률에 따라서 오차가 생기게 된다. 본 연구에서는 비접촉 축진동측정시 발생되는 오차에 대하여 검토하고자 한다. from the studies, the origin of ${\alpha}$$_1$peak was attributed to the detrapping process form trap with 2.88[eV] deep of injected space charge from the chathode in the crystaline regions. The origin of ${\alpha}$$_2$ peak was regarded as the detrapping process of ions trapped with 0.9[eV] deep originated from impurity-ion remained in the specimen during production process of the material, in the crystalline regions. The origin of ${\beta}$ peak was concluded to be due to the depolarization process of "C=0"dipole with the activation energy of 0.75[eV] in the amorphous regions. The origin of ${\gamma}$ peak was responsible to the process combined with the depolarization of "CH$_3$", chain segment, with the activation energy of carriers from the shallow trap with 0.

• Journal of the Korean earth science society
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• v.34 no.6
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• pp.588-601
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• 2013

In geophysics and geophysical exploration fields, we can use information about inclination and azimuth in various ways. These include borehole deviation logging for inversion process, real-time data acquisition system, geophysical monitoring system, and so on. This type of information is also necessarily used in the directional drilling of shale gas fields. We thus need to develop a subminiature, low-powered, multi-functional inclination and azimuth measurement system for geophysical exploration fields. In this paper, to develop real-time measurement system, we adopt the high performance low power Micro Control Unit (made with state-of-the-art Complementary Metal Oxide Semiconductor technology) and newly released Micro Electro Mechanical Systems Attitude Heading Reference System sensors. We present test results on the development of a multifunctional real-time inclination and azimuth measurement system. The developed system has an ultra-slim body so as to be installed in 42mm sonde. Also, this system allows us to acquire data in real-time and to easily expand its application by synchronizing with a depth encoder or Differential Global Positioning System.