• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.2
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• pp.60-66
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• 2014

A control oriented model of the Lean $NO_x$ trap (LNT) was developed to determine the timing of $NO_x$ regeneration. The LNT model consists of $NO_x$ storage and reduction model. Once $NO_x$ is stored ($NO_x$ storage model), at the right timing $NO_x$ should be released and then reduced ($NO_x$ reduction model) with reductants on the catalyst active sites, called regeneration. The $NO_x$ storage model simulates the degree of stored $NO_x$ in the LNT. It is structured by an instantaneous $NO_x$ storage efficiency and the $NO_x$ storage capacity model. The $NO_x$ storge capacity model was modeled to have a Gaussian distribution with a function of exhaust gas temperature. $NO_x$ release and reduction reactions for the $NO_x$ reduction model were modeled as Arrhenius equations. The parameter identification was optimally performed by the data of the bench flow reactor test results at space velocity 50,000/hr, 80,000/hr, and temperature of $250-500^{\circ}C$. The LNT model state, storage fraction indicates the degree of stored $NO_x$ in the LNT and thus, the timing of the regeneration can be determined based on it. For practical purpose, this model will be verified more completely by engine test data which simulate the NEDC transient mode.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.5A
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• pp.611-617
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• 2000

Asynchronous mode W-CDMA system is kmown to be quite appropriate to the next generation mobile communication system, especially in a non-homogenious cellular architecture. In this case, however, each base station needs to use different spreading code for identification, so it is a demeanding task for a mobile terminal to find the best cell site and get an accurate code synchronization at the beginning of a communication. Since slow acquisition of a base station could mean the failure of initiation, a fast algorithm to accelerate the cell search process is essential. In this paper, a new cell search algorithm based on the binary code position modulation within the code block is proposed. Different cell sites are identified by different hopping code sequences, andeach position modulation is performed by the hopping code. The proposed algorithm is proved to make the cell search time in most places in a cell much shorter than the previous algorithms, and to make the receiver implementation simpler.

• Journal of the korean veterinary medical association
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• v.38 no.4
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• pp.376-382
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• 2002

호주의 많은 소동물 임상수의사들이 최근에 관심을 갖고 있는 부분은 개의 아토피(Canine Atopy)에서의 알러지-특이성(Allergen-specific)IgE에 쓰이는 혈청 ELISA (Enzyme-Linked Immuno-Sorbent Assay, 효소결합면역흡착검사)테스트의 활용 가능성에 관한 것이다. 희망사항은 개 아토피의 진단과 치료에 있어서 도움이 되도록 접근할 수 있는 시험(Accessible test)일 것이다. 아토피(Atopy)는 진단과 치료를 실패시키는 질병이며, 새로운 ELISA라도 이 문제를 쉽게 해결하여 주지 못한다. 개의 아토피에서 알려진(Allergens)들을 분석하는 데 쓰이는 혈청 ELISA처럼 아주 정확하게 특성화되어져야 한다. 해당 개는 아토피성(Atopic)으로서 진단되어져야만 되고 그 다음에 치료에 지침이 되도록 개별 알러진 동정(Individual allergen identification)용 ELISA로 개의 혈액을 스크린하는데 적합하여야 한다. ELISA와 피내접종시험(Internal testing)방법은 상관도가 낮고 그렇기 때문에 어떤 시험이 더 신뢰할 수 있는 것일까? 이러한 사실은 논쟁의 여지가 있으며 이상의 2가지 시험들이 옳다면 각각의 상응하는 각각 다른 아형(Subtypes)의 아토피라고 볼 수있다. 아마도 알러진들은 경피적으로 흡수되어 아토피성피부염으로 되어진다. 그것은 인체에서 건초열(Hay fever)이나 천식(Asthma)과 같이 흡입에 의해 일으키는 유사한 증후군동종 (Syndrome akin)과 같은 접근의 초기양식(Primary mode of access)으로부터 생기는 다른 유사한 질병과정이 되어질 수도 있다. 이러한 2가지 증후군은 함께 병발하는 경우가 있다. 의학에서는 피부 반점시험방법의 예비조사연구(Preliminary research with skin patch testing in medicine)는 아토피성 피부염을 야기하는 알러진들의 경피흡수경로의 개념을 지지해준다. 흡인 알러진들을 사용한 개들에서의 도전 시험(Challenge tests)들은 거의 대부분이 비-피부학적 임상증상들을 발현하였다. 모든 증거가 분명히 나타나도록 미래의 조사연구를 인도해 주는 게 필요하며 개 아토피의 정의와 진단을 둘러싼 수수께끼를 해결하는데 도움이 될 것이다.

• The Journal of Korean Medicine
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• v.26 no.1 s.61
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• pp.187-194
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• 2005

Objective: Two Korea-mode sport beverages with medicinal herbs added, Saeng Mac San (SMS) and Je Ho Tang (JHT), were developed by the Ginseng Research Group of the Korea Food Research Institute. For their practical usage, we examined their taste tests at rest including sense-analysis (S-A) and preference-inquiry (P-I). Methods: Five beverage-treatments, SMS, JHT and three commercial sport beverages (CSBs) and a control (CON) were offered randomly. Eighty-two subjects under stable control of their taste sense filled out the questionnaires for their S-A and p-I, which were developed by the Exercise Physiology Laboratory of Kyungpook National University. The collected data $(means{\pm}SD)$ were analyzed by repeated measures one-way ANOVA; Tukey' s test was administrated for identification of statistically significant differences (p<0.05). Results: Overall beverage likeability values of SMS and JHT were significantly lower than those of CSBs, JHT lower than CON. Overall flavor values of SMS and JHT were significantly lower than those of CSBs and CON. SMS was similar to CON in the amount of flavor. SMS and JHT were less tart than CSBs and the former was significantly lower than CSBs and CON in four drinkability-related items. Conclusion : SMS rated less than CSBs in tartness and the amount of flavor. JHT was avoided most. Thus, the results indicate that JHT is not fit as a sport beverdge and the overall likeability of SMS must be elevated by way of strengthening its tartness and amount of flavor for practical usage.

• Steel and Composite Structures
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• v.28 no.2
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• pp.223-231
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• 2018

Nowadays, there are a great number of various structures that have been retrofitted by using different FRP Composites. Due to this, more researches need to be conducted to know more the characteristics of these structures, not only that but also a comparison among them before and after the retrofitting is needed. In this research, a model steel structure is tested using a bench-scale earthquake simulator on the shake table, using recorded micro tremor data, in order to get the dynamic behaviors. Columns of the model steel structure are then retrofitted by using GFRP composite, and then tested on the Quanser shake table by using the recorded micro tremor data. At this stage, it is needed to evaluate the dynamic behaviors of the retrofitted model steel structure. Various types of methods of OMA, such as EFDD, SSI, etc. are used to take action in the ambient responses. Having a purpose to learn more about the effects of GFRP composite, experimental model analysis of both types (retrofitted and no-retrofitted models) is conducted to evaluate their dynamic behaviors. There is a provision of ambient excitation to the shake table by using recorded micro tremor ambient vibration data on ground level. Furthermore, the Enhanced Frequency Domain Decomposition is used through output-only modal identification. At the end of this study, moderate correlation is obtained between mode shapes, periods and damping ratios. The aim of this research is to show and determine the effects of GFRP Composite implementation on structural responses of the model steel structure, in terms of changing its dynamical behaviors. The frequencies for model steel structure and the retrofitted model steel structure are shown to be 33.916% in average difference. Finally, it is shown that, in order to evaluate the period and rigidity of retrofitted structures, OMA might be used.

• Smart Structures and Systems
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• v.25 no.1
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• pp.81-96
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• 2020

Wind measurements were made on the Canton Tower at a height of 461 m above ground during the Typhoon Vincente, the wind-induced accelerations and displacements of the tower were recorded as well. Comparisons of measured wind parameters at upper level of atmospheric boundary layer with those adopted in wind tunnel testing were presented. The measured turbulence intensity can be smaller than the design value, indicating that the wind tunnel testing may underestimate the crosswind structural responses for certain lock-in velocity range of vortex shedding. Analyses of peak factors and power spectral density for acceleration response shows that the crosswind responses are a combination of gust-induced buffeting and vortex-induced vibrations in the certain range of wind directions. The identified modal frequencies and mode shapes from acceleration data are found to be in good agreement with existing experimental results and the prediction from the finite element model. The damping ratios increase with amplitude of vibration or equivalently wind velocity which may be attributed to aerodynamic damping. In addition, the natural frequencies determined from the measured displacement are very close to those determined from the acceleration data for the first two modes. Finally, the relation between displacement responses and wind speed/direction was investigated.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.251-267
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• 1991

Plastic strength analysis using plastic failure mode as a limit state is adopted instead of a conventional elastic structural analysis to predict the ultimate strength of Web frame idealized by a plane frame. Linear programming arid Compact procedure are developed for determining the collapse load factor. It is found that the final results are good agreement with the results of Elasto-plastic analysis. Besides, the redundant structures like Web frame is known to have multiple failure modes. Web frame may collapse under any of the possible failure modes. Thus, the identification of these possible failure modes is necessary and very important in the reliability analysis of Web frame. In order to deal with multiple failure modes, automatic generation method of all failure modes and basic failure modes is used for selecting the dominant failure modes. The probability of failure pastic collapse of Web frame is calculated using these dominant failure modes. The safety of Web frame is asscssed and compared by performing the deterministic and probabilistic analysis.

• Korean Journal of Crystallography
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• v.8 no.1
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• pp.33-37
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• 1997

The optical properties of (1210) GaN epitaxy films grown on the (1012) $\alpha-A1_2O_3$ substrates have been studied. The hetero-epitaxy films were grown by the halide vapor phase epitaxy (HVPE) method using $Ga/HC1/NH_3/He$ system at $990^{\circ}C$. XRD, RHEED and SEM are used for the identification of the hetero-epitaxy films structure and surface morphology. The confirmed (1210) GaN epitaxy films were characterized by PL and Raman. By the Raman scattering, the active phonon modes of single-phase GaN films are varied with the arrangement of both polarization and propagation directions of laser beam with reference to the axis in single-phase crystal films. The Y(Z, Y & Z) X geometry allows scattering pat-terns of $A_1(TO)=533\;cm^{-1},\;E_1(TO)=559\;cm^{-1}\;and\;E_2=568 cm^{-1}$ modes, whereas in the Z(Y, Y & Z) X geometry the only $E_2$ mode are observed.

• Earthquakes and Structures
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• v.8 no.4
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• pp.889-913
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• 2015

Structural vibration characteristics of a semi-active base-isolated building were investigated using seismic observation records including those of the 2011 Great East Japan earthquake (Tohoku earthquake). Three different types of analyses were conducted. First, we investigated the long-term changes in the natural frequencies and damping factors by using an ARX model and confirmed that the natural frequency of the superstructure decreased slightly after the main shock of the Tohoku earthquake. Second, we investigated short-term changes in the natural frequencies and damping factors during the main shock by using the N4SID method and observed different transition characteristics between the first and second modes. In the second mode, in which the superstructure response is most significant, the natural frequency changed depending on the response amplitude. In addition, at the beginning of the ground motion, the identified first natural frequency was high possibly as a result of sliding friction. Third, we compared the natural frequencies and damping factors between the conditions of a properly functional semi-active control system and a nonfunctional system, by using the records of the aftershocks of the Tohoku earthquake. However, we could not detect major differences because the response was probably influenced by sliding friction, which had a more significant effect on damping characteristics than did the semi-active dampers.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.959-962
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• 2005

Recently, business integration and interoperability of between the heterogeneous applications are requested by rapid growth of web. Web Services that self-contained for platform and programming language is appeared used to XML of standard data format. Such amid Fast Web Services attract attention at fields necessary to bring rapid communication like Mobile and RFID. In this paper, we inquired about ASN.1 of ITU-T and IS0/IEC standard that a central role of data transform. And we studied encoding process of between ASN.1 and XML for transform SOAP massage of a massage transfer mode of Web Services to binary data.