• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.8
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• pp.107-118
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• 1995

Three-dimensional simulator for thermal oxidation process is developed. The simulator is consisted by two individual module, one is analytic-model module and the other is numerical-model module. The analytic-model which uses simple complementary-error function guarantees fast calculation in prediction of multi-dimensional oxidation process. The numerical-model which is based on boundary element method (BEM), has a good accuracy and suitable for various process conditions. The results of this study show that oxide growth is retarded at the corner of hole structure and enhanced at the corner of island structure. These effects are reson of different distribution of oxidant diffusion and mask stress. The utility of models and simulator developed in this study is demonstrated by using it to predict not only traditional shape of LOCOS but also process effects in small geometry.

• International Journal of Automotive Technology
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• v.5 no.3
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• pp.165-172
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• 2004

Phenomenological models for direct injection diesel engine emissions including NO, soot, and HC were implemented into a full engine cycle simulation and validated with experimental data obtained from representative heavy-duty DI diesel engines. The cycle simulation developed earlier by Jung and Assanis (2001) features a quasi-dimensional, multi-zone, spray combustion model to account for transient spray evolution, fuel-air mixing, ignition and combustion. In this study, additional models for HC emissions were newly implemented and the models for NO, soot, and HC emissions were validated against experimental data. It is shown that the models can predict the emissions with reasonable accuracy. However, additional effort may be required to enhance the fidelity of models across a wide range of operating conditions and engine types.

• Communications for Statistical Applications and Methods
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• v.6 no.1
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• pp.305-318
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• 1999

In this paper we derive the higher order expansions of the first four cumulants of multi-dimensional Maximum Likelihood Estimator (MLE) under the general parametric model up to and including terms of order O({{{{ {n }^{-1 } }}}}) Also we obtain the explicit form of the expansion of the normalizing trans formation of multi-dimensional MLE and show that the suggested normalizing process is much better than the normal approximation based on central limit theorem through example.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.9
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• pp.4320-4333
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• 2017

Energy-efficient virtual resource allocation algorithm has become a hot research topic in cloud computing. However, most of the existing allocation schemes cannot ensure each type of resource be fully utilized. To solve the problem, this paper proposes a virtual machine (VM) allocation algorithm on the basis of multi-dimensional resource, considering the diversity of user's requests. First, we analyze the usage of each dimension resource of physical machines (PMs) and build a D-dimensional resource state model. Second, we introduce an energy-resource state metric (PAR) and then propose an energy-aware multi-dimensional resource allocation algorithm called MRBEA to allocate resources according to the resource state and energy consumption of PMs. Third, we validate the effectiveness of the proposed algorithm by real-world datasets. Experimental results show that MRBEA has a better performance in terms of energy consumption, SLA violations and the number of VM migrations.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.7
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• pp.1063-1071
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• 2004

Accurate heat release analysis of cylinder pressure data is important for evaluating performance in the development of diesel engine However, traditional single zone first law heat release model(SZM) has significant limitations due to the simplified assumption of uniform charge and neglecting local temperature inside cylinder during combustion process. In this study. heat release rate based on single zone heat release model has been evaluated by comparison with computational analysis results using Fire code which is based on multi-dimensional model(MDM). To overcome limitations due to simplicity of single zone assumption. especially the influence of specific heat ratio on gross heat release has been esteemed and newly suggested were the equation $\gamma$= $\gamma$(${T/T}_{max}$) which describes the variations of gases thermodynamic properties with mean temperature and maximum mean temperature inside cylinder Single zone heat release model applied with this equation is shown to give very good results over whole range of operating conditions when compared with computational analysis results based on multi-dimensional model.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.9 s.240
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• pp.997-1005
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• 2005

The extinction characteristics of low strain rate normal gravity (1-g) nonpremixed methane-air flames were studied numerically and experimentally. A time-dependent axisymmetric two-dimensional (2D) model considering buoyancy effects and radiative heat transfer was developed to capture the structure and extinction limits of 1-g flames. One-dimensional (1D) computations were also conducted to provide information on 0-g flames. A 3-step global reaction mechanism was used in both the 1D and 2D computations to predict the measured extinction limit and flame temperature. A specific maximum heat release rate was introduced to quantify the local flame strength and to elucidate the extinction mechanism. Overall fractional contribution by each term in the energy equation to the heat release was evaluated to investigate the multi-dimensional structure and radiative extinction of 1-g flames. Images of flames were taken for comparison with the model calculation undergoing extinction. The two-dimensional numerical model was validated by comparing flame temperature profiles and extinction limits with experiments and ID computation results. The 2D computations yielded insight into the extinction mode and flame structure of 1-g flames. Two combustion regimes depending on the extinction mode were identified. Lateral heat loss effects and multi-dimensional flame structure were also found. At low strain rates of 1-g flame ('Regime A'), the flame is extinguished from the weak outer flame edge, which is attributed to multi-dimensional flame structure and flow field. At high strain rates, ('Regime B'), the flame extinction initiates near the flame centerline due to an increased diluent concentration in reaction zone, which is the same as the extinction mode of 1D flame. These two extinction modes could be clearly explained with the specific maximum heat release rate.

• Korean Journal of Construction Engineering and Management
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• v.14 no.6
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• pp.61-69
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• 2013

In the mixed-use development program, several conflicts occur due to the characteristics of construction program, such as large-scale, variety of stakeholders, long periods of time, etc. In particular, since the characteristics of the construction program having various complex projects lead to different requirements depending on stakeholders, it is crucial to plan the appropriate type and size of facilities. Therefore, it is necessary to derive solutions suitable for the needs of owner by conducting VE in the planning phase. In this study, a multi-dimensional quality model is developed to present proper facilities necessary for the construction program by clearly identifying the owner's requirements in performing VE in the planning phase. Through the development of the multi-dimensional quality model, the characteristics distribution of 15 major facilities by 12 performance indicators for mixed-use development programs is presented. The deduction method of appropriate facilities based on the requirements of owner and the multi-dimensional synthesis method among the performance indicators are also suggested. This study is significant as a basic research for the application of VE in the planning phase of construction program. It is expected that the multi-dimensional quality model proposed in this study could facilitate presentation and review of appropriate facilities based on the analysis of requirements of various stakeholders in the early stage of the construction program.

• Management Science and Financial Engineering
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• v.7 no.1
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• pp.27-39
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• 2001

The multi-projective model considers attributes and the relationships among attributes called projections. The critical features of the multi-projective model are the way of relating attributes in the description of the system, the way of reasoning incomplete projections, and the determination of connected patterns between projection. In order to get a full picture of the system, we build a set of projections. The multi-projective model can be thought of as projections of a multi-dimensional reality onto simplified “model space”. The multi-projective database modeling approach used in this paper unified the ideas and terminology of various database models. Most importantly, the multi-projective modeling is presented as a tool of database design in the relational and other database models.

• Water Engineering Research
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• v.1 no.2
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• pp.147-158
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• 2000

In this study, we characterized the seasonal variation of rainrate fields in the Han river basin using the WGR multi-dimensional precipitation model (Waymire, Gupta, and Rodriguez-Iturbe, 1984) by estimating and comparing the parameters derived for each month and for the plain area, the mountain area and overall basin, respectively. The first-and second-order statistics derived from observed point gauge data were used to estimate the model parameters based on the Davidon-Fletcher-Powell algorithm of optimization. As a result of the study, we can find that the higher rainfall amount during summer is mainly due to the arrival rate of rain bands, mean number of cells per cluster potential center, and raincell intensity. However, other parameters controlling the mean number of rain cells per cluster, the cellular birth rate, and the mean cell age are found invariant to the rainfall amounts. In the application to the downstream plain area and upstream mountain area of the Han river basin, we found that the number of storms in the mountain area was estimated a little higher than that in the plain area, but the cell intensity in the mountain area a little lower than that in the plain area. Thus, in the mountain area more frequent but less intense storms can be expected due to the orographic effect, but the total amount of rainfall in a given period seems to remain the same.

• Smart Media Journal
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• v.10 no.4
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• pp.21-27
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• 2021

Recently, the importance of counseling is increasing due to the Corona Blue caused by COVID-19. Also, with the increase of non-face-to-face services, researches on chatbots that have changed the counseling media are being actively conducted. In non-face-to-face counseling through chatbot, it is most important to accurately understand the client's emotions. However, since there is a limit to recognizing emotions only in sentences written by the client, it is necessary to recognize the dimensional emotions embedded in the sentences for more accurate emotion recognition. Therefore, in this paper, the vector and sentence VAD (Valence, Arousal, Dominance) generated by learning the Word2Vec model after correcting the original data according to the characteristics of the data are learned using a deep learning algorithm to learn the multi-dimensional We propose an emotion recognition model. As a result of comparing three deep learning models as a method to verify the usefulness of the proposed model, R-squared showed the best performance with 0.8484 when the attention model is used.