• Korean Chemical Engineering Research
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• v.56 no.2
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• pp.204-211
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• 2018

In this study, densities of water + N-Methyldiethanolamine (MDEA), Water + 2-Amino-2-Methyl-1-Propanol (AMP), MDEA + AMP binary systems and Water+MDEA+AMP ternary system were measured over the full range of composition at temperatures from 303.15 K to 333.15 K by using an Anton Paar digital vibrating tube densimeter (DMA4500). The experimental excess volumes have been obtained from the experimental density results and have been fitted using the Redlich-Kister-Muggianu expression. The parameters obtained from the binary excess volume data were used for the correlation of ternary system with one additional ternary parameter for each isotherm. All investigated binary and ternary systems are completely miscible, because the values of excess volume are negative under the examined conditions.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.7 no.4
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• pp.178-187
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• 2014

The purpose of this study is to study the coexistent development of the touristic and education cultures of temples. For the study, an investigation on the actual conditions of temples in Youngwol and a set of interviews were conducted from 13th June to 7th November in 2014. The analysis was conducted through the field observations and the interviews with building owners based on the criteria and SPSSWIN 18.0 program was used for statistical processes. The results of analysis are as follows. First, the temples are found to be the extremely valuable local cultural assets with the cultural values and historical backgrounds. Second, the major temple buildings show that they have the unique and distinct characteristics that cannot be found from other general temples, so it is necessary for developing the unique local tourism resources from them. Third, since the study shows that there is a lack of tourism and educational culture resources, so a relevant plan thereof is urgently required. The implication of this study is that there is an urgent necessity for the succession and the modern reinterpretation regarding the cultures of traditional temples, based on which a shift of viewpoint to the digital tourism, which covers both the traditional temple cultures and the modern cultures, could arise.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.5
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• pp.781-793
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• 2014

A Public Key Infrastructure (PKI) is security standards to manage and use public key cryptosystem. A PKI is used to provide digital signature, authentication, public key encryption functionality on insecure channel, such as E-banking and E-commerce on Internet. A soft-token private key in PKI is leaked easily because it is stored in a file at standardized location. Also it is vulnerable to a brute-force password attack as is protected by password-based encryption. In this paper, we proposed a new method that detects private key compromise and is probabilistically secure against a brute-force password attack though soft-token private key is leaked. The main idea of the proposed method is to use a genuine signature key pair and (n-1) fake signature key pairs to make an attacker difficult to generate a valid signature with probability 1/n even if the attacker found the correct password. The proposed method provides detection and notification functionality when an attacker make an attempt at authentication, and enhances the security of soft-token private key without the additional cost of construction of infrastructure thereby extending the function of the existing PKI and SSL/TLS.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.385-390
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• 2006

This paper examines the sampling and jitter specifications and considerations for Global Navigation Satellite Systems (GNSS) software receivers. Software radio (SWR) technologies are being used in the implementation of communication receivers in general and GNSS receivers in particular. With the advent of new GPS signals, and a range of new Galileo and GLONASS signals soon becoming available, GNSS is an application where SWR and software-defined radio (SDR) are likely to have an impact. The sampling process is critical for SWR receivers, where it occurs as close to the antenna as possible. One way to achieve this is by BandPass Sampling (BPS), which is an undersampling technique that exploits aliasing to perform downconversion. BPS enables removal of the IF stage in the radio receiver. The sampling frequency is a very important factor since it influences both receiver performance and implementation efficiency. However, the design of BPS can result in degradation of Signal-to-Noise Ratio (SNR) due to the out-of-band noise being aliased. Important to the specification of both the ADC and its clocking Phase- Locked Loop (PLL) is jitter. Contributing to the system jitter are the aperture jitter of the sample-and-hold switch at the input of ADC and the sampling-clock jitter. Aperture jitter effects have usually been modeled as additive noise, based on a sinusoidal input signal, and limits the achievable Signal-to-Noise Ratio (SNR). Jitter in the sampled signal has several sources: phase noise in the Voltage-Controlled Oscillator (VCO) within the sampling PLL, jitter introduced by variations in the period of the frequency divider used in the sampling PLL and cross-talk from the lock line running parallel to signal lines. Jitter in the sampling process directly acts to degrade the noise floor and selectivity of receiver. Choosing an appropriate VCO for a SWR system is not as simple as finding one with right oscillator frequency. Similarly, it is important to specify the right jitter performance for the ADC. In this paper, the allowable sampling frequencies are calculated and analyzed for the multiple frequency BPS software radio GNSS receivers. The SNR degradation due to jitter in a BPSK system is calculated and required jitter standard deviation allowable for each GNSS band of interest is evaluated. Furthermore, in this paper we have investigated the sources of jitter and a basic jitter budget is calculated that could assist in the design of multiple frequency SWR GNSS receivers. We examine different ADCs and PLLs available in the market and compare known performance with the calculated budget. The results obtained are therefore directly applicable to SWR GNSS receiver design.

• KIPS Transactions on Software and Data Engineering
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• v.7 no.4
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• pp.145-152
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• 2018

In electronic textbooks (or e-Textbooks) the traditional paper-based textbooks are enriched with multimedia contents and new features such as interactive multimedia-based simulation, interactive quizzes, and content sharing. It has been envisioned that e-Textbooks will gradually replace the traditional paper-based textbooks in classrooms in the near future. HTML5 is an emerging and promising standard that enables web applications (or apps) to incorporate rich multimedia contents such as video clips, flash movies and simulation-based demonstration, as well as to provide cross-platform functionality which allows the apps to run on a diverse range of platforms. To support rich multimedia contents and cross-platform functionality, with respect to HTML5, this paper presents the new features, compares the current trend of mobile apps (e.g., native, web-based and hybrid apps) for e-Textbook development. In order to investigate the suitability of these three development approaches for e-Textbooks, we present a case study on our recent work in developing e-Textbooks using HTML5 and JavaScript, as well as analyses the challenges associated with HTML5 features (e.g, compatibility with web browsers) for developing e-Textbooks.

• Journal of Information Management
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• v.39 no.2
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• pp.45-74
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• 2008

The purpose of this study was to promote the understanding of laboratory notebook's record characteristics through getting a line on the importance of the notebooks which have record, information, communication, and proof functions. To improve the research ethics and cultures, this study was examined and investigated by literature references and survey results. This study analyzed the status of the notebooks in part of laboratory information system of the R&D institutes, paper notebooks for laboratory records management, and the introduction of ELN for digital record. For the notebook's institutionalization, more review is needed to the possibility of involvement in the conflict, evidential requisite and signature by inspector, the limitation of autonomous policy for the notebook's operation, the difficulty of preservation for 30 years, the introduction of ELN and utilization for the notebooks. To improve management and institutionalization for the notebooks, it is needed to the notebook's record for knowledge management and evidential values, support and budget for the notebook's management department, researcher's recognition conversion for the notebooks related to the intellectual property and technology transference, the record method train for the notebooks from the university classes, and the introduction of ELN related to the laboratory information management system or project management system.

• Journal of the Korean association of regional geographers
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• v.13 no.2
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• pp.171-186
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• 2007

This paper was to examine the existing foundation of cultural contents industry through analyzing the development process, the location pattern, and the value chain system and the management of cultural contents industry in Daegu. Most cultural contents industry in Daegu had less than ten employees: so, it was classified into the early stage of commercialization. The firms that dealt with on-line distribution were recently founded. The high portion of the finns was located in the center of city such as Jung-Gu and Nam-Gu in which the Center for Digital Industry Promotion of Daegu (DIP) is located. The value main system consisted of four nodes such as creation node, production node, marketing node and distribution node. The production node was played the most important role. Based on value chain system, the cultural contents industry firms in Daegu could be divided into four types: Type I is a contents production firm with a single value chain in the cultural contents industry. Type II is a contents production firm with two or three value chains. Type III is a contents production firm with comprehensive value chain. Type IV is a non contents production firm with multiple value chains.

• Applied Microscopy
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• v.29 no.1
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• pp.83-94
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• 1999

The ultrastructure of small arterioles and capillaries in the lumbrical muscles of rat digits were studied by electron microscopy and following results were obtained. 1. The diameter of small arterioles of rat digits were $12\sim20{\mu}m$, and it was relatively smaller than human $(30\sim35{\mu}m)$. 2. All the endothelial cells of small arterioles and capillaries in the lumbrical muscles of rat digits were continuous type, and they had typical morphological characteristics of continuous endothelial cells : numerous cytoplasmic pinocytic vesicles and many tight junctions between the endothelial cells. 3. In the small arterioles subendothelial layers were irregularly spaced beneath the basal lamina, and membrane to membrane contacts were found between the endothelial cells and smooth muscle cells. 4. Pericytes were often found nearby capillary endothelium, and their cytoplasmic processes surrounded part of endothelial cells. They were enclosed by basal lamina. 5. Smooth muscle cells in tunica media of small arterioles were only one layered, that is, they were terminal arterioles. Sarcoplasm of smooth muscle cell was divided to 2 areas; homogeneous or filamentous area and non-homogeneous perinuclear area. 6. The tunica adventitia contained fibroblasts with extremely attenuated cytoplasmic processes and collagen fibirls.

• Journal of Broadcast Engineering
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• v.10 no.3
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• pp.413-421
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• 2005

As the population of HDTV is growing, among many useful features of modern set top boxes (STBs) or digital video recorders (DVRs), video browsing, visual bookmark, and picture-in-picture capabilities are very frequently required. These features typically employ reduced-size versions of video frames, or thumbnail images. Most thumbnail generation approaches generate DC images directly from a compressed video stream. A discrete cosine transform (DCT) coefficient for which the frequency is zero in both dimensions in a compressed block is called a DC coefficient and is simply used to construct a DC image. If a block has been encoded with field DCT, a few AC coefficients are needed to generate the DC image in addition to a DC coefficient. However, the bit length of a codeword coded with variable length coding (VLC) cannot be determined until the previous VLC codeword has been decoded, thus it is required that all codewords should be fully decoded regardless of their necessary for DC image generation. In this paper, we propose a method especially for fast DC image generation from an I-frame using multiple-symbol lookup table (mLUT). The experimental results show that the method using the mLUT improves the performance greatly by reducing LUT count by 50$\%$.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.1
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• pp.89-98
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• 2016

In this paper, we proposed an automated areal feature matching method based on geometric similarity without user intervention and is applied into areal features of many-to-many relation, for confusion of spatial data-sets of different scale and updating cycle. Firstly, areal feature(node) that a value of inclusion function is more than 0.4 was connected as an edge in adjacency matrix and candidate corresponding areal features included many-to-many relation was identified by multiplication of adjacency matrix. For geometrical matching, these multiple candidates corresponding areal features were transformed into an aggregated polygon as a convex hull generated by a curve-fitting algorithm. Secondly, we defined matching criteria to measure geometrical quality, and these criteria were changed into normalized values, similarity, by similarity function. Next, shape similarity is defined as a weighted linear combination of these similarities and weights which are calculated by Criteria Importance Through Intercriteria Correlation(CRITIC) method. Finally, in training data, we identified Equal Error Rate(EER) which is trade-off value in a plot of precision versus recall for all threshold values(PR curve) as a threshold and decided if these candidate pairs are corresponding pairs or not. To the result of applying the proposed method in a digital topographic map and a base map of address system(KAIS), we confirmed that some many-to-many areal features were mis-detected in visual evaluation and precision, recall and F-Measure was highly 0.951, 0.906, 0.928, respectively in statistical evaluation. These means that accuracy of the automated matching between different spatial data-sets by the proposed method is highly. However, we should do a research on an inclusion function and a detail matching criterion to exactly quantify many-to-many areal features in future.