• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.3A
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• pp.352-361
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• 2000

The performance of a multi-carrier CDMA system is analyzed considering frequency selective multipath fading and Near/Far effects. The number of multicarrier, multiuser, and arms of RAKE receiver, and the decay ratio of frequency selective multipath fading are used as a parameter for the performance analysis. More over, the distribution and the strength of multiuser interference are also considered. To evaluate the Near/Far effects in a multi-carrier CDMA system, three distribution models are assumed. In the first model, interference to carrier Ratio, I/C, ranges from -4 dB to 4dB, and at each 2 dB interval, 20 % of multiuser is assumed to be uniformly distributed. In the second one, I/C ranges from -2 dB to 2 dB, and 33.3% of multiuser is assumed to be equally dispersed at each 2dB interval. The third model is 0 dB of I/C, that is, with perfect power control, multiuser are assumed to be evenly located. In this paper, multi-carrier CDMA system adoption RAKE receiver is proposed to mitigate the frequency selective multipath fading. From the results, the third model(i.e. perfect power control) shows the best performance, and the narrower range of I/C causes the less effects to the desired signal, which reads to the better performance.

• Reproductive and Developmental Biology
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• v.33 no.3
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• pp.119-123
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• 2009

The two dimensional quantitative structure-activity relationships (2D-QSARs) models concerning the binding affinity constants ($p[Od.]_{50}$) between 2-cyclohexyltetrahydropyrane and 2-cyclohexyltetrahydrofurane analogues as substrates, and bovine odorant binding protein (bOBP) as receptor were derived by multiple regression analyses method and discussed. The statistical quality of the optimized 2D-QSAR model (5) was good (r=0.907). From the model, the binding affinity constants ($p[Od.]_{50}$) were dependent upon the optimal value ($(TL)_{opt.}$=2.737) of total lipole (TL) of substrate molecules. Based on these findings, the high active compounds predicted by optimized 2D-QSAR model (5) were 2-(dimethylcyclohexyl)tetrahydropyrane molecule and their isomer molecules. The binding affinity constants regarding bOBP of the tetrahydrofuryl-2-yl family compounds were dependent upon the hydrophobicity (logP) of whole substrate molecules. In any case of porcine odorant-binding proteins (pOBP), the constants were dependent upon the hydrophobicity (${\pi}x={\log}P_X-{\log}P_H$) of substituents (R) in substrate molecules. Also, from the optimal values of hydrophobic constant, the hydrophobicity for bOBP influenced ca. twice time bigger (bOBP>pOBP) than that for pOBP.

• The KIPS Transactions:PartB
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• v.9B no.5
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• pp.563-570
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• 2002

Robust extraction of 3D facial features and global motion information from 2D image sequence for the MPEG-4 SNHC face model encoding is described. The facial regions are detected from image sequence using multi-modal fusion technique that combines range, color and motion information. 23 facial features among the MPEG-4 FDP (Face Definition Parameters) are extracted automatically inside the facial region using color transform (GSCD, BWCD) and morphological processing. The extracted facial features are used to recover the 3D shape and global motion of the object using paraperspective camera model and SVD (Singular Value Decomposition) factorization method. A 3D synthetic object is designed and tested to show the performance of proposed algorithm. The recovered 3D motion information is transformed into global motion parameters of FAP (Face Animation Parameters) of the MPEG-4 to synchronize a generic face model with a real face.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.1
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• pp.108-115
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• 1996

This paper proposes an algorithm and a model topology for the connected speech recognition using Discrete Hidden Markov Models. A proposed model uses diphone and triphone model which consider the recognition rate and recognisable vocabulary. Considering more exact inter- phoneme segmentation and execution speed of algorithm, 4 states have to exist in diphone model where the first state and the last state are keeping a steady state, the other states hold a transient state. 7 states have to exist in triphone model where 7 states are specified and improved to 3 steady states and 4 transition states. Also, the proposed speech recognition algorithm is designed to detect the inter-phoneme segmentation during the recognition processing.

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.149-154
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• 2019

This paper is to study the durability through structural analysis on the front undercover of SUV car for offroad. It was investigated which model became structurally best by analyzing three kinds of models which are similar to the configuration of undercover for the protection of the part under car body which has been used really. The models of undercover were designed through CATIA program and analyzed by using ANSYS program as three kinds of models A, B and C. Through the analysis results, model B was expressed to have the best durability as model B has the least equivalent stress and the longest fatigue life among three models. As the design data with the durability of undercover obtained on the basis of this study result are utilized, the esthetic sense can be shown by being grafted onto the machine or structure at real life.

• Korean Journal of Remote Sensing
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• v.39 no.2
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• pp.207-221
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• 2023

This study suggests deep neural network models for estimating air temperature with Level 1B (L1B) datasets of GEO-KOMPSAT-2A (GK-2A). The temperature at 1.5 m above the ground impact not only daily life but also weather warnings such as cold and heat waves. There are many studies to assume the air temperature from the land surface temperature (LST) retrieved from satellites because the air temperature has a strong relationship with the LST. However, an algorithm of the LST, Level 2 output of GK-2A, works only clear sky pixels. To overcome the cloud effects, we apply a deep neural network (DNN) model to assume the air temperature with L1B calibrated for radiometric and geometrics from raw satellite data and compare the model with a linear regression model between LST and air temperature. The root mean square errors (RMSE) of the air temperature for model outputs are used to evaluate the model. The number of 95 in-situ air temperature data was 2,496,634 and the ratio of datasets paired with LST and L1B show 42.1% and 98.4%. The training years are 2020 and 2021 and 2022 is used to validate. The DNN model is designed with an input layer taking 16 channels and four hidden fully connected layers to assume an air temperature. As a result of the model using 16 bands of L1B, the DNN with RMSE 2.22℃ showed great performance than the baseline model with RMSE 3.55℃ on clear sky conditions and the total RMSE including overcast samples was 3.33℃. It is suggested that the DNN is able to overcome cloud effects. However, it showed different characteristics in seasonal and hourly analysis and needed to append solar information as inputs to make a general DNN model because the summer and winter seasons showed a low coefficient of determinations with high standard deviations.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.11
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• pp.1568-1574
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• 2017

This paper studied cogging torque reduction effect for sloping notch applied two notches on stator teeth. We have confirmed accuracy of FEM(Finite Element Method) through comparison previous model using asymmetric notch for experiment and 3D FEM results, and then cogging torque comparison of previous model and sloping notch model. Also the sloping notch model has been modified to step-sloping notch model to consider manufactur. The modification method of sloping notch changed the degree of slope of notch (a)(Notch(a) sloping Deg) and the degree of Slope of notch (b)(Notch(b) Sloping Deg). When Cogging torque is case of minimum, Notch (a) Sloping Deg is $-12[^{\circ}]$ and Notch(b) Sloping Deg $12[^{\circ}]$. In this case, cogging torque was about 23.9[mNm]. Cogging torque of previous model is about 40.8[mNm], so sloping notch model is less than previous model by 41.42[%]. Also, if sloping notch model is changed to step-sloping notch model, cogging torque of step-sloping notch model is about 24.82[mNm], Therefore the difference between the two cogging torque is about 3.85[%], so step-sloping notch model can be applied when considering manufacture.

• Journal of Industrial Technology
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• v.27 no.A
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• pp.121-130
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• 2007

Centrifuge model tests were performed to find appropriate equations proposed previously of estimating the bearing capacity of the composite clayey soil reinforced with sand compaction pile. Model tests were carried out with changing the replacement ratio of SCP (20%, 40%, 70%), contents of fine materials (5%, 10%, 15%) and ratio of treated width to loading width (1B, 2B, 3B). Test results about bearing capacity of the composite ground were obtained by performing the surcharge load tests with measurements of applied loads and vertical displacement. Bearing capacities against bulging and shear failures were estimated by the existing equations. As results of comparing the estimated bearing capacity with experimental values the bearing capacities estimated by Greenwood's equation (1970) for bulging failure mode were similar to the test results.

• Journal of the Korean Society for information Management
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• v.18 no.3
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• pp.219-238
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• 2001

This paper is proposed next generation digital library models which based on the understanding of changes in digital library and business paradigm. The models which were proposed at the paper are applied electronic commerce technologies to digital libraries. The logical model was developed in the area of library material acquisition to participate various related agents during acquisition processes into single eMarketplace. The paper was developed detailed eMarketplace logical model to integrate and transact library material acquisition process.

• Journal of Korean Society of Transportation
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• v.9 no.1
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• pp.29-46
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• 1991

The purpose of this study is to develop a parking behavior model in prior step for solv-ing parking problems in Pusan C. B. D. The results of this study are as follows; In the C. B. D of Pusan the peak parking time is between 2 and 3 o'clock P. M., and the average parking duration is 237 minutes. It means the use of parking lots is very ineffi-cient. Hence in order to shorten the parking duration, it is very urgent for drivers to chan-ge parking attitude. The walking distance from the parking lots to his destination is below 300∼500m, so the establishment of parking areas and the arrangement of parking lots in C. B. D should be planned on the base of the above walking distance. The model distinguishing between legal and illegal parking behaviors is derived from the binary decision model. The selected model has the correlation rate, η2=0.505 which is relatively high value This result shows that the detetminating judgement on the legal and illegal parking behavior is influenced mutually such factors as driver's occupation parking purpose monthly income distance to his destination averaged parking duration and age.