• Journal of Industrial Technology
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• v.21 no.B
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• pp.91-98
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• 2001

In this paper, center detection and motion analysis of a moving object are studied. Kohonen's self-organizing neural network models are used for the moving objects tracking and time delay neural networks are used for dynamic characteristic analysis. Instead of objects brightness, neuron projections by Kohonen Networks are used. The motion of target objects can be analyzed by using the differential neuron image between the two projections. The differential neuron image which is made by two consecutive neuron projections is used for center detection and moving objects tracking. The two differential neuron images which are made by three consecutive neuron projections are used for the moving trajectory estimation. It is possible to distinguish 8 directions of a moving trajectory with two frames and 16 directions with three frames.

• 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.

• Survey Research
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• v.11 no.2
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• pp.71-95
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• 2010

Base population, intercensal and postcensal population estimates, and population projections have been regularly published as official populations. Base population is usually made out based on census conducted every 5 or 10 years, and is most important from which intercensal, postcensal estimates, and population projections are derived. We investigate how base population in Korea is made out and then compare it with those of other countries. We also present problems arising from making out base population in Korea.

• Journal of the Korean Data and Information Science Society
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• v.18 no.4
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• pp.955-961
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• 2007

Population projections provides useful basic information for the need of economic resources and labor forces. The National Office of Statistics(NSO) presents population projections for the whole country and some of higher level local governments, but not do projections of the lower level local governments. Here are some projection methods as Hamilton-Perry methods and modified auto regression methods, which are compared to cohort method published by NSO in case of Daegu metropolitan city. The simulation results are a little stagnant with modified auto regression, but a little declines are shown with NSO and HP method, for 2010, 2015 and 2020 year, respectively.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.63.5-63
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• 2001

In this paper, moving objects tracking and dynamic characteristic analysis are studied. Kohonen´s self-organizing neural network models are used for moving objects tracking and time delay neural networks are used for dynamic characteristic analysis. Instead of objects brightness, neuron projections by Kohonen Networks are used. The motion of target objects can be analyzed by using the differential neuron image between the two projections. The differential neuron image which is made by two consecutive neuron projections is used for center detection and moving objects tracking. The two differential neuron images which are made by three consecutive neuron projections are used for the moving trajectory estimation.

• Imaging Science in Dentistry
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• v.48 no.3
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• pp.167-176
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• 2018

Purpose: In the age of X-ray computed tomography (CT) and digital volume tomography (DVT), with their outstanding post-processing capabilities, indications for planar radiography for the study of the dentition of ancient Egyptian mummies may easily be overlooked. In this article, the advantages and limitations of different approaches and projections are discussed for planar oral and maxillofacial radiography using portable digital X-ray equipment during archaeological excavations. Furthermore, recommendations are provided regarding projections and sample positioning in this context. Materials and Methods: A total of 55 specimens, including 19 skeletonized mandibles, 14 skeletonized skulls, 18 separate mummified heads, and 4 partially preserved mummies were imaged using portable digital X-ray equipment in the course of archaeological excavations led by the University of Basel in the Valley of the Kings between 2009 and 2012. Images were evaluated by 2 authors with regard to the visibility of diagnostically relevant dental structures using a 4-point grading system(Likert scale). Results: Overall, the visibility of diagnostically relevant dental structures was rated highest by both authors on X-ray images acquired using a dental detector. The tube-shift technique in the lateral projections of mandibular dentition achieved the second-best rating, and lateral projections achieved the third-best rating. Conclusion: Conventional planar digital X-ray imaging, due to its ubiquity, remains an excellent method-and often the only practicable one-for examining the skulls and teeth of ancient Egyptian mummies under field conditions. Radiographic images of excellent diagnostic quality can be obtained, if an appropriate methodology regarding the selected projections and sample placement is followed.

• East Asian mathematical journal
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• v.18 no.2
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• pp.235-243
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• 2002

In this paper, we get conditions for the natural projections of some product manifolds with varying metrics of two Riemannian manifolds to be harmonic, and necessary and sufficient conditions for some product manifolds with the harmonic natural projections of two Einstein manifolds to be Einstein manifolds.

• Journal of radiological science and technology
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• v.40 no.4
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• pp.543-548
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• 2017

The aim of this study was to evaluate anteroposterior oblique(RPO, LPO) and posteroanterior oblique(LAO, RAO) projections of the cervical spine, at various kVp and mA s increments, in order to compare thyroid surface dose. Using Rando phantom, dosimeter was attached to the Cervical spine 4~5 to measure the surface dose in the same thyroid position. As a result, the surface dose was $595.08{\pm}215.01{\mu}Gy$ for anteroposterior oblique(RPO, LPO) projections and $64.21{\pm}33.49{\mu}Gy$ for posteroanterior oblique(LAO, RAO) projections by changing kVp increment. The surface dose was $445.20{\pm}230.90{\mu}Gy$ for anteroposterior oblique(RPO, LPO) projections and $44.51{\pm}22.77{\mu}Gy$ for posteroanterior oblique(LAO, RAO) projections by changing mAs increment. The posteroanterior oblique method could reduce about 90% the surface dose than the anteroposterior oblique method. There were statistically significant differences among the examinations(p<0.001). Change the direction of position to reduce the surface dose at oblique projection of cervical spine. Therefore, we consider posteroanterior oblique projections than anteroposterior oblique projections of cervical spine examination in other to reduce patient surface dose.

• Computers and Concrete
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• v.9 no.6
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• pp.439-455
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• 2012

The interaction of plan geometry and structural configuration, a determinative factor in the earthquake behavior of buildings, has become a serious issue in the building industry in Turkey due to the poor seismic performance of R/C buildings during the latest earthquake. Consequently, designing new buildings without structural irregularities against earthquake loads is proving to be more significant. This study focuses on the effects of plan geometries on earthquake performances of buildings. In that respect, structural irregularities in the plan are investigated in detail based on the Turkish Earthquake Code (TEC 2007). The study is based on five main parametric models and a total of 40 sub-models that are grouped according to their plan geometries with excessive projections such as L-shaped, H-shaped, T-shaped and U-shaped models. In addition to these, a square model without any projections is also generated. All models are designed to have the same storey gross area but with different number of storeys. Changes in the earthquake behavior of buildings were evaluated according to the number of storeys, the projection ratios and the symmetry conditions of each model. The analysis of each structural irregularity resulted in many findings, which were then assessed. The study demonstrates that the square model delivers the best earthquake performance owing to its regular plan geometry.

• Journal of the Korean Data and Information Science Society
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• v.26 no.1
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• pp.31-39
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• 2015

This paper deals with a method for estimating variance components on the basis of projections under the assumption of random effects model. It discusses how to use projections for getting sums of squares to estimate variance components. The use of projections makes the vector subspace generated by the model matrix to be decomposed into subspaces that are orthogonal each other. To partition the vector space by the model matrix stepwise procedure is used. It is shown that the suggested method is useful for obtaining Type I sum of squares requisite for the ANOVA method.