• Geophysics and Geophysical Exploration
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• v.13 no.4
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• pp.315-322
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• 2010

The phase-screen and the split-step Fourier migrations, which are implemented in both the frequency-wavenumber and frequency-space domains by using one-way scalar wave equation, allow imaging in laterally heterogeneous media with less computing time and efficiency. The generalized-screen migration employs the series expansion of the exponential, unlike the phase-screen and the split-step Fourier migrations which assume the vertical propagation in frequency-wavenumber domain. In addition, since the generalized-screen migration generalizes the series expansion of the vertical slowness, it can utilize higher-order terms of that series expansion. As a result, the generalized-screen migration has higher accuracy in computing the propagation with wide angles than the phase-screen and split-step Fourier migrations for media with large and rapid lateral velocity variations. In this study, we developed a 2D prestack generalized-screen migration module for imaging a complex subsurface efficiently, which includes various dips and large lateral variations. We compared the generalized-screen propagator with the phase-screen propagator for a constant perturbation model and the SEG/EAGE salt dome model. The generalized-screen propagator was more accurate than the phase-screen propagator in computing the propagation with wide angles. Furthermore, the more the higher-order terms were added for the generalized-screen propagator, the more the accuracy was increased. Finally, we compared the results of the generalizedscreen migration with those of the phase-screen migration for a model which included various dips and large lateral velocity variations and the synthetic data of the SEG/EAGE salt dome model. In the generalized-screen migration section, reflectors were positioned more accurately than in the phase-screen migration section.

• Korean Institute of Interior Design Journal
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• v.26 no.1
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• pp.33-42
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• 2017

Interior design especially the design developments for commercial spaces should ensure the economy of spaces. This is the marketing for space. It is necessary to understand the design elements of commercial space for the efficient using of digital media of space marketing. In this research decided to design application schemes for shopping mall by searching fashion shopping behaviors of users with persona-base scenario approach. Collected the information of users behavior base on case analysis of advance research to make personas. And develop scenario base personas for knowing the needs of users. And then made 4 schemes as the solution. Scheme 1. Customers can get the information and communication with the staff through with media screen in one room of shopping mall. The data of customers can be recorded for providing information or product recommendation personality. Forecast to preferred by group trip or customers that don't like walking around in shopping mall. Scheme 2. Install a media screen at entrance of a store in shopping mall and show special effect to raise customers' attention who walk through from the front of the store. Through with this customers will stay for long time and raise curiosity to get in the store. And the media screen also provide information of store and products. Scheme 3. Customers can get the information of products with using smart phone to scan QR cord in labels of products and record. Customers can finish whole shopping behaviors without the help of store staff. And can make buying decision even have left shopping mall as a online mode. Scheme 4. Store managers can record the products and the environment of store with 360 camera and update to website. Then customers can browse the virtual space with VR glasses. That make customers can have the real shopping experience without being in the store. In this study, have presented schemes of digital media in commercial space. But there are various of commercial space. In this study was presented schemes for shopping mall by searching fashion shopping behaviors of users. And look forward the researches about specific space setting and other type of commercial space for space development.

• Honam Mathematical Journal
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• v.35 no.3
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• pp.329-342
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• 2013

We study lightlike hypersurfaces M of a semi-Riemannian space form $\tilde{M}(c)$ with a semi-symmetric non-metric connection whose structure vector field is tangent to M. Our main result is two characterization theorems for such a lightlike hypersurface.

• The Korean Journal of Air & Space Law and Policy
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• v.22 no.2
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• pp.155-175
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• 2007

As intellectual terror threats increase, we feel the limit in coping with those threats and the things we do are placing traditional X-ray machines & ETD and increasing aviation security staffs. In fact, even if air transportation system is the fast and most efficient transportation methods, it is true that there are many inconveniences to endure due to terror threats. In the name of security, even if we make a lot of efforts and time to screen both good-natured passengers, baggage, cargo and suspicious passengers, it is impossible to screen perfectly and it is not an efficient methods. Therefore, we introduce profiling system that reduce the effort to screen good-natured passengers but focus on screening dangerous passengers and baggages. Profiling system strengthens aviation security, using the concept "Selection & Concentration". Israel started to introduce manual profiling system in aviation security, which is interviewing suspicious passengers and it has been used in crime investigation since 1960. And it has been upgraded and diversified to CAPPS(Computer Assisted Passenger Screening Program) and SPOT(Screening Passenger by Observation). So, this theses is to study on the concept & kind of profiling and profiling methods adopted in airlines. Also it presents the method of introduction of profiling system in Korea and the necessity of making law on it.

• Journal of the HCI Society of Korea
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• v.2 no.2
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• pp.45-51
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• 2007

Space planning is one of the popular applications of VR technology including interior design, architecture design, and factory layout. In order to provide easier methods to accommodate physical objects into virtual space planning task, we suggest applying mixed reality (MR) interface. We describe our hardware and software of our MR system designed according to requirements of the application domain. In brief, our system hardware consists of a video see-through display with a touch screen interface, mounted on a mobile platform, and we use screen space 3D manipulations to arrange virtual objects within the MR scene. Investigating the interface with our prototype implementation, we are convinced that our system will help users to design spaces in more easy and effective way.

• Bulletin of the Korean Mathematical Society
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• v.51 no.4
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• pp.979-994
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• 2014

We study half lightlike submanifold M of an indefinite trans-Sasakian manifold such that its structure vector field is tangent to M. First we study the general theory for such half lightlike submanifolds. Next we prove some characterization theorems for half lightlike submanifolds of an indefinite generalized Sasakian space form.

• Journal of the Korean Society of Costume
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• v.53 no.7
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• pp.57-68
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• 2003

The purpose of this study is to develop a creative perspective technique in fashion illustration through analyzing perspective in visual art experienced a great variety. This study was analyzed by examining the general theories based on the discovery of perspective and investigating the modern perspective in fashion illustration related to the method of spatial expression in visual art. A complex perspective of existing perspective gives the effect of reapperance of actual space and three-dimentional form in a plane. Because of being used as not only one perspective technique but also some perspectives technique, its expression can be more realistic. An amplified perspective gives the effect of visual illusion just like being suck in space inside and come out from screen outside by distorting the human body. A confused perspective of space gives the visual illusional effect of collapsing actual space and misunderstanding three-dimensional form by distorting the form of the space and changing the nature as an object of fashion. A reiterated or duplicated perspective gives effect of interpreting invisible space as imaginary space by overlapping and eliminating the object of fashion. An irrational perspective of spatial illusion gives the effect of disorganization experienced thinking by strange shapes and new recognition of irrational space by extraordinary visual connection. It has a tendency to surrealism. In conclusion, the modern perspective in fashion illustration has made the best use of not only new perspective since 1980, but general perspective before 1980. By the modern perspective expression. the viewer has made a chance to experience imaginary spaces indirectly, and the author has been able to express emotions by his or her new attempt in the screen.

• Journal of the Korea Computer Graphics Society
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• v.8 no.3
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• pp.1-7
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• 2002

This paper presents a practical technique for approximating the boundary surface of the volume swept out by three-dimensional objects using the depth-buffer. Objects may change their geometries and orientations while sweeping. The sweep volume is approximated as a union of volume elements, which are just rendered inside appropriate viewing frusta of virtual cameras and mapped into screen viewports with depth-buffer. From the depth of each pixel in the screen space of each rendering, the corresponding point in the original world space can be computed. Appropriately connecting these points yields polygonal faces forming polygonal surface patches approximately covering some portion of the sweep volume. Each view frustum adds one or more surface patches in this way, and these presumably overlapped polygonal surface patches approximately enclose the whole sweep volume. These patches may further be processed to yield non-overlapped polygonal surfaces as an approximation to the boundary of the original 3D sweep volume.

• Journal of Korea Multimedia Society
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• v.25 no.2
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• pp.411-420
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• 2022

Entering the digital cinema era, movies and games are remediating each other. The shots of digital movies are being transformed into realistic content through digital Moving long-take shots that transcend time and space and move smoothly. At this time, the digital Moving long take shot that continuously captures the space in all directions without an external screen induces a game experience. In addition, the camera that constantly accompanies the person enhances the sense of immersion in the game in a way similar to the point of view of the game. While various immersive device contents represented by VR, AR and XR are emerging, the advent of <1917> suggests significant implications for post-cinema in that it creates a game experience while maintaining the traditional screen environment and cinematic paradigm.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.2
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• pp.50-56
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• 1972

This study has been carried out to observe the driving and the intercepting effects of air screen on some sea-water fishes ; Chrysophrys major, Mylio macrocephalus, Fugu pardalis. 1. By perforating fine holes on the compressed air pipes, air screen was formed in the water, and this screen was set at $45^{\circ}$, and $90^{\circ}$ against the fish passage to observe the reactions on the part of the fish. 2. Changes were given to the location of the air screen in the water to observe how the air screen drived the fish to its direction. 3. The effective distance between holes on the air piprs was determined by a series of experiments of setting up two air screens of various types in hole distance, by moving a screen to-ward the other, and of observing the distance between two screens when fish eseape through the space. The results of the above experiments observed as follows were : 1. The passage of fish was effectively intercepted by setting up the air screens at 45 degrees against the fish passage and it was also intercepted when the screen was set at 90 degrees against the passage. 2. Fish could be driven by moving the air screen toward the fish. 3. The air screen formed from the pipe above than 0.3mm in diameter was effective, but less than 0.2mm was not sufficiently effective. 4. The strength of the air pressure in the pipe should be higher than $0.087kg/cm^2$. 5. The fish holding ability to obtain effective air screen was ranged as following when the air pressure was $0.160kg/cm^2$. and the hole diameter was 0.3mm on the 12.6mm pipe, depending upon the intervals of the holes on the pipe: The shortest distance which could hold fish between two screens was 59.4cm when the holes were perforated at every 40cm; 33.5cm when at every 30cm; 28.75cm when at every 10cm: and 27.25cm when at every 5cm. Thus, no significant change was at served when the holes were perforated more densely than 30cm intervals. Therefor the hole intervals should be 30cm in designing fishing gear employing air screen.