• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.171-176
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• 2016

This paper proposes road safety facilities applying Hot-dip zinc-aluminum-magnesium alloy-coated steel sheets and coils to reduce the loss of function caused by the corrosion of steel in the service state. Vehicle crash simulations and full-scale crash tests were carried out to provide reliable information on evaluating the crash performance with the products of road safety facilities built with hot-dip zinc-aluminum-magnesium alloy-coated steel. From the results of the simulations and full-scale crash tests, the impact behaviors evaluated by the three-dimensional crash simulations considering the strain-rate dependency in a constitutive model were similar to those obtained from the full-scale crash test results. The full-scale crash test results met the crashworthiness evaluation criteria; hence, the proposed bridge barrier in this paper is ready for field applications.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.2
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• pp.161-168
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• 2015

An experimental study was conducted to scrutinize the influence of the frequency of an ultrasonic standing wave on the variation in the behavior of a methane-air premixed flame. The evolutionary features of the propagating flame were captured by a high-speed camera, and the macroscopic flame behavior, including the flame structure and local velocities, was investigated in detail using a post-processing analysis of the high-speed images. It was found that a structural variation and propagation-velocity augmentation of the methane-air premixed flame were caused by the intervention of the ultrasonic standing wave, which enhanced the combustion reaction. Conclusive evidence for the dependency of the flame behaviors on the driving frequency of the ultrasonic standing wave and equivalence ratio of the reactants is presented.

• Korean Journal of Cognitive Science
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• v.19 no.1
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• pp.89-105
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• 2008

In this paper, we suggest a rule-based system for the prediction of natural prosodic phrase breaks from Korean texts. For the implementation of the rule-based system, (1) sentence constituents are sub-categorized according to their syntactic functions, (2) syntactic phrases are recognized using the dependency relations among sub-categorized constituents, (3) rules for predicting prosodic phrase breaks are created. In addition, (4) the length of syntactic phrases and sentences, the position of syntactic phrases in a sentence, sense information of contextual words have been considered as to determine the variable prosodic phrase breaks. Based on these rules and features, we obtained the accuracy over 90% in predicting the position of major break and no break which have high correlation with the syntactic structure of the sentence. As for the overall accuracy in predicting the whole prosodic phrase breaks, the suggested system shows Break_Correct of 87.18% and Juncture Correct of 89.27% which is higher than that of other models.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.5
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• pp.375-379
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• 2009

Protein domain is the conserved unit of compact tree-dimensional structure and evolution, which carries specific function. Domains may appear in patterns in proteins, since they have been conserved through the evolution for functional formation of proteins. In this paper, we propose a formulated method for conservation analysis of domain combination based on association rule. Proposed method measures mutual dependency of domains in a combination, as well as co-occurrence frequency of them, which is conventionally used. Based on the method, we extracted conserve domain combinations in S.cerevisiae proteins and analyzed their functions based on Gene Ontology. From the results, we drew conclusions that domains in S.cerevisiae proteins form patterns whose members are highly affiliated to one another, and that extracted patterns tend to be associated with molecular function. Moreover, the results testified to proposed method superior to conventional ones for identifying domain combinations conserved for functional cooperation.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.1.1-1.1
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• 2011

Printed electronics based on the direct writing of solution processable functional materials have been of paramount interest and importance. In this talk, the synthesis of printable inorganic functional materials (conductors and semiconductors) for thin-film transistors (TFTs) and photovoltaic devices, device fabrication based on a printing technique, and specific characteristics of devices are presented. For printable conductor materials, Ag ink is designed to achieve the long-term dispersion stability and good adhesion property on a glass substrate, and Cu ink is sophisticatedly formulated to endow the oxidation stability in air and even aqueous solvent system. The both inks were successfully printed onto either polymer or glass substrate, exhibiting the superior conductivity comparable to that of bulk one. In addition, the organic thin-film transistor based on the printed metal source/drain electrode exhibits the electrical performance comparable to that of a transistor based on a vacuum deposited Au electrode. For printable amorphous oxide semiconductors (AOSs), I introduce the noble ways to resolve the critical problems, a high processing temperature above $400^{\circ}C$ and low mobility of AOSs annealed at a low temperature below $400^{\circ}C$. The dependency of TFT performances on the chemical structure of AOSs is compared and contrasted to clarify which factor should be considered to realize the low temperature annealed, high performance AOSs. For photovoltaic application, CI(G)S nanoparticle ink for solution processable high performance solar cells is presented. By overcoming the critical drawbacks of conventional solution processed CI(G)S absorber layers, the device quality dense CI(G)S layer is obtained, affording 7.3% efficiency CI(G)S photovoltaic device.

• Korean journal of communication and information
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• v.38
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• pp.245-275
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• 2007

This study analyzes interactivity between formal policy and informal trade practices at outside production market of broadcasting production environment in Korea. For this, this study raises three topics. First, the trait of historical context of policy making at outside broadcasting production policy: Second, the trait and meaning of path dependency behavior in the process of trade practices between over-the-air TV Organization and independent production companies : Three, the meaning of interactivity between formal policy and informal trade practices at outside broadcasting production market. Major findings of this study are : the trait of policy making was concentrated on the quantitative rates of the outside production program. And, the trait of trade practices was unfair rivalry in accordance with the custom of insider dealing. The chief cause of the conflict structure of outside broadcasting production market is lacked in policy complement at the qualitative dimension.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5C
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• pp.726-736
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• 2004

In this paper, we proposed a new scalar multiplier structure needed for an elliptic curve cryptosystem(ECC) over the standard basis in GF(2$^{163}$ ). It consists of a bit-serial multiplier and a divider with control logics, and the divider consumes most of the processing time. To speed up the division processing, we developed a new division algorithm based on the extended Euclid algorithm. Dynamic data dependency of the Euclid algorithm has been transformed to static and fixed data flow by a localization technique, to make it independent of the input and field polynomial. Compared to other existing scalar multipliers, the new scalar multiplier requires smaller gate counts with improved processor performance. It has been synthesized using Samsung 0.18 um CMOS technology, and the maximum operating frequency is estimated 250 MHz. The resulting performance is 148 kbps, that is, it takes 1.1 msec to process a 163-bit data frame. We assure that this performance is enough to be used for digital signature, encryption/decryption, and key exchanges in real time environments.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.177-184
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• 2014

In chemical vapor deposition(CVD) tungsten silicide(WSix) dual poly gate(DPG) scheme, we observed the fluorine effects on gate oxide using the electrical and physical measurements. It is found that in fluorine-rich WSix NMOS transistors, the gate thickness decreases as gate length is reduced, and it intensifies the roll-off properties of transistor. This is because the fluorine diffuses laterally from WSix to the gate sidewall oxide in addition to its vertical diffusion to the gate oxide during gate re-oxidation process. When the channel length is very small, the gate oxide thickness is further reduced due to a relative increase of the lateral diffusion than the vertical diffusion. In PMOS transistors, it is observed that boron of background dopoing in $p^+$ poly retards fluorine diffusion into the gate oxide. Thus, it is suppressed the fluorine effects on gate oxide thickness with the channel length dependency.

• Journal of Korean Society of Rural Planning
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• v.11 no.2 s.27
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• pp.43-49
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• 2005

As information has been brought to public attention, information storage as well as information usability has been important. Rural information is produced in many areas and institutions. However, it is difficult to use rural information comprehensively. Since formats for management are various, it is difficult to have unified frame. In this research, a schema of database fer integrating rural data is designed to improve usability using dimensional modeling. First of all, rural data are analyzed for designing integrated rural database schema. Rural data used are 'National Agricultural Statistics' and 'Gun annual statistical report'. Analysis shows that there are three considerations; administrative district, time-dependency and classification of data. Considering these three requisite, we designed database schema using dimensional modeling. The reason of using dimensional modeling is to improve usability and effectiveness. If the database was designed using ER modeling, many tables have to be joined every searching time. Separately from integrated rural database schema, user's database schema is designed considering usability. Through user's database, users can modify data or generate new data and save these processes. These make it possible to use generated data repeatedly. We evaluate usability, contribution, and effectiveness of data manipulation on the integrated rural database. We propose an integrated rural database structure improving the accessibility and usability of rural data and information and verified the data model based on a practical example.

• The Korean Journal of Applied Statistics
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• v.32 no.5
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• pp.763-782
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• 2019

This paper proposes a probabilistic document ranking model incorporating term dependencies. Document ranking is a fundamental information retrieval task. The task is to sort documents in a collection according to the relevance to the user query (Qin et al., Information Retrieval Journal, 13, 346-374, 2010). A probabilistic model is a model for computing the conditional probability of the relevance of each document given query. Most of the widely used models assume the term independence because it is challenging to compute the joint probabilities of multiple terms. Words in natural language texts are obviously highly correlated. In this paper, we assume a multinomial distribution model to calculate the relevance probability of a document by considering the dependency structure of words, and propose an information retrieval model to rank a document by estimating the probability with the maximum entropy method. The results of the ranking simulation experiment in various multinomial situations show better retrieval results than a model that assumes the independence of words. The results of document ranking experiments using real-world datasets LETOR OHSUMED also show better retrieval results.