• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.285-288
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• 2004

This study presents a numerical procedure to optimize the shape of dimple surface to enhance turbulent heat transfer in rectangular channel. The response surface based optimization method is used as an optimization technique with Reynolds-averaged Wavier-Stokes analysis of fluid flow and heat transfer with shear stress transport (SST) turbulence model. The dimple depth-to -dimple print diameter ratio, channel height- to- dimple print diameter ratio. and dimple print diameter-to-pitch ratio are chosen as design variables. The objective function is defined as a linear combination of heat transfer coefficient and friction drag coefficient with a weighting factor. Full factorial method is used to determine the training points as a mean of design of experiment.

• Journal of IKEEE
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• v.25 no.1
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• pp.42-46
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• 2021

A novel key exchange cryptographic method utilizing biometric finger print as a user's private key is proposed. Each unknown users' finger print is encrypted by optical phase-shifting interferometry principle and is changed into two ciphers, which are exchanged with the other party over a public communication network for secret key sharing. The transmitted ciphers generate a complex hologram, which is used to calculate a shared secret key for each user. The proposed method provides high security when applied to a secret key sharing encryption system.

• Journal of Korea Multimedia Society
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• v.8 no.11
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• pp.1510-1519
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• 2005

We proposed a digital watermarking method that it is possible to identify the copyright because the watermark is detected in the first print-scan and to protect a forgery because the watermark is not detected in the second print-scan. The proposed algorithm uses LPM and DFT transform for the robustness to the distortion of pixel value and geometrical distortion. This methods could improve watermark detection performance and image quality by selecting maximum sampling radius in LPM transform. After analyzing the characteristics of print-scan process, we inserted the watermark in the experimentally selected frequency bands that survives robustly to the first print-scan and is not detected in the second print-scan, using the characteristic of relatively large distortion in high frequency bands of DFT As the experimental result, the original proof is possible because average similarity degree 5.13 is more than the critical value 4.0 in the first print-scan. And the detection of forgery image is also possible because average similarity degree 2.76 is less than the critical value 4.0 in the second print-scan.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.12A
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• pp.2067-2073
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• 2001

Biometric systems are forms of technology that use unique human physical characteristics to automatically identify a person. They have sensors to pick up some physical characteristics, convert them into digital patterns, and compare them with patterns stored for individual identification. However, lip-print recognition has been less developed than recognition of other human physical attributes such as the fingerprint, voice patterns, retinal at blood vessel patterns, or the face. The lip print recognition by a CCD camera has the merit of being linked with other recognition systems such as the retinal/iris eye and the face. A new method using multi-resolution architecture is proposed to recognize a lip print from the pattern kernels. A set of pattern kernels is a function of some local lip print masks. This function converts the information from a lip print into digital data. Recognition in the multi-resolution system is more reliable than recognition in the single-resolution system. The multi-resolution architecture allows us to reduce the false recognition rate from 15% to 4.7%. This paper shows that a lip print is sufficiently used by the measurements of biometric systems.

• The Journal of Advanced Prosthodontics
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• v.8 no.6
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• pp.457-464
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• 2016

PURPOSE. The aim of this study was to determine whether two methods of documentation, print and electronic forms, for the assessment of patient-reported outcomes (PRO) in complete denture wearers provide comparable results. The study also quantified the time needed for filling the forms by each method. MATERIALS AND METHODS. Thirty participants enrolled in a university clinic answered two forms (a questionnaire for denture satisfaction and OHIP-EDENT). They provided answers with two application methods in a random order, with a one-month interval between them: (1) electronic forms on a tablet computer; and (2) print forms. The methods were compared in terms of mean results, correlation/agreement, internal consistency, and spent time. RESULTS. Mean results for both methods were similar for each denture satisfaction item (100-mm VAS) and OHIP-EDENT summary score. Both questionnaires presented good internal consistency regardless of the application method (Cronbach's ${\alpha}=0.86$ or higher). Correlation and agreement between the methods regarding specific items was at least moderate for the majority of cases. Mean time for the electronic and print forms were 9.2 and 8.5 minutes, respectively (paired t test, P=.06, non-significant). CONCLUSION. The electronic method is comparable to print forms for the assessment of important PRO of prosthetic treatment for edentulism, considering the results and time needed. Findings suggest the viability of replacing print forms with a tablet for applying the tested inventories in clinical trials.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1815-1821
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• 2015

Rapid increase in population growth has made the mankind to delve in appropriate identification of individuals through biometrics. Foot Print Recognition System is a new challenging area involved in the Personal recognition that is easy to capture and distinctive. Foot Print has its own dimensions, different in many ways and can be distinguished from one another. The main objective is to provide a novel efficient automated system Segmentation using Foot Print based on structural relations among the features in order to overcome the existing manual method. This system comprises of various statistical computations of various foot print parameters for identifying the factors like Instep-Foot Index, Ball-Foot Index, Heel- Index, Toe- Index etc. The input is naked footprint and the output result to an efficient segmentation system thereby leading to time complexity.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.1
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• pp.57-65
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• 2016

This paper was analyzed the characteristics of piezoelectric inkjet print head using finite element method(FEM). It showed the bending node driving of piezoelectric and relation theory principle consider piezoelectric material characteristics and ink characteristics. From such result we were had the piezoelectric head design and manufacture. It got a this head characteristics through experiment, we confirmed that proper voltage control is possible to through ink drop control experiment of piezoelectric print head. This paper was obtained the suitable ink jetting characteristics that manufacture the control circuit and piezoelectric inkjet print head. This practice product was applied to improvement of PCB electric circuit pattern by etching resist ink that PCB manufactured to complex process over traditional 6 stages can be simpled to 1 stage by inkjet printing technology.

• Journal of the Korean Home Economics Association
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• v.30 no.4
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• pp.1-13
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• 1992

A computer simulation method for textile designs was developed using a generic-purpose graphics program, LUMENA and its results were applied for costume design simulation. Its design performance was comparable with those using specialized design package programs which are in general very expensive. Three areas of textile design, print pattern design, weaving design, and knitting design, were covered. In the print pattern design simulation, a gird network library was constructed by using basic methods of repeat, and a pattern library by scanning existing print patterns. Through the modification and synthesis of library patterns, many new print patterns could be obtained. In the weaving design simulation, a thread library and a draw-down library were constructed. Using them, simulations of woven textile structures were carried out. In the knitting design simulation, a stitch library and a detail library were made from various types of knit stitch and detail drawings of knit costume, respectively. They were used to make structural knitting patterns and jacquard knitting designs. Using those simulated textile designs, costume design simulation was carried out.

• Journal of Korea Multimedia Society
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• v.16 no.9
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• pp.1057-1066
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• 2013

Personal verification using finger-knuckle-print(FKP) uses lines and creases at the finger-knuckle area, so the orientation information of texture is an important feature. In this paper, we propose an effective FKP verification method which extracts keypoints using SIFT algorithm and matches the keypoints by vector similarity. The vector is defined as a direction vector which connects a keypoint extracted from a query image and a corresponding keypoint extracted from a reference image. Since the direction vector is created by a pair of local keypoints, the direction vector itself represents only a local feature. However, it has an advantage of expanding a local feature to a global feature by comparing the vector similarity among vectors in two images. The experimental results show that the proposed method is superior to the previous methods based on orientation codes.

• Journal of Korea Multimedia Society
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• v.21 no.8
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• pp.1021-1026
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• 2018

3D SCAN enables easy human body measurement via a digital method in the process of film costume production which used to be done manually. Software-oriented computer graphic, which integrates 3D SCAN data in the process of manual film costume production, can induce quick and diverse design outcomes. While, 3D PRINT, which integrates computer graphic data in the process of manual film costume production, can automate the process of special costume production using a digital method. Integration of 3D Scan + Computer Graphic + 3D Print using integrated platforms for tailored costume production as developed in this study allows significant reduction of costume production period and costs. It also allows efficient integration of costume production outcomes in various industries related with OSMU contents in particular. In other words, using it, we can create a new business market that integrates multiple areas of film content, drama content and game content.