• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.28 no.9
• /
• pp.1408-1414
• /
• 2004

The use of flip-chip technology has many advantages over other approaches for high-density electronic packaging. ACF (anisotropic conductive film) is one of the major flip-chip technologies, which has short chip-to-chip interconnection length, high productivity, and miniaturization of package. In this study, thermal fatigue lift of ACF bonding flip-chip package has been predicted. Elastic and thermal properties of ACF were measured by using DMA and TMA. Temperature dependent nonlinear hi-thermal analysis was conducted and the result was compared with Moire interferometer experiment. Calculated displacement field was well matched with experimental result. Thermal fatigue analysis was also conducted. The maximum shear strain occurs at the outmost located bump. Shear stress-strain curve was obtained to calculate fatigue life. Fatigue model for electronic adhesives was used to predict thermal fatigue life of ACF bonding flip-chip packaging. DOE (Design of Experiment) technique was used to find important design factors. The results show that PCB CTE (Coefficient of Thermal Expansion) and elastic modulus of ACF material are important material parameters. And as important design parameters, chip width, bump pitch and bump width were chose. 2$^{nd}$ DOE was conducted to obtain RSM equation far the choose 3 design parameter. The coefficient of determination ($R^2$) for the calculated RSM equation is 0.99934. Optimum design is conducted using the RSM equation. MMFD (Modified Method for feasible Direction) algorithm is used to optimum design. The optimum value for chip width, bump pitch and bump width were 7.87mm, 430$\mu$m, and 78$\mu$m, respectively. Approximately, 1400 cycles have been expected under optimum conditions. Reliability analysis was conducted to find out guideline for control range of design parameter. Sigma value was calculated with changing standard deviation of design variable. To acquire 6 sigma level thermal fatigue reliability, the Std. Deviation of design parameter should be controlled within 3% of average value.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.12
• /
• pp.2747-2754
• /
• 2012

This thesis explains the development of multiple LCD system with the additional function to maximize the utilization of PC contents. The newly developed system is composed of host LCD and slave LCD. Host LCD decodes and outputs the image and voice of NTSC, PAL, SECAM signals. It also converts the decoded signals into LVDS signals before transmitting them to slave LCD stage. In addition, the installation of CF Memory and USB Memory helps display multi-media data. Unlike the host LCD, since not including the tuner and memory part, the slave LCD can't receive TV signals and play video signals. It only has the function to receive LVDS image signals and display on a LCD panel. This newly developed multi-LCD system has competitiveness in various aspects. With its simple structure, the failure rate, price and display power are relatively low due to its simplification of the control part. It has price and functional competitiveness as the product whose host LCD can control the entire slave LCD in terms of channel, volume, and video output.

• Journal of the Microelectronics and Packaging Society
• /
• v.6 no.2
• /
• pp.13-21
• /
• 1999

Flip chip assembly directly on organic boards offers miniaturization of package size as well as reduction in interconnection distances resulting in a high performance and cost-competitive Packaging method. This paper describes the investigation of alternative low cost flip-chip mounting processes using electroless Ni/Au bump and anisotropic conductive adhesives/films as an interconnection material on organic boards such as FR-4. As bumps for flip chip, electroless Ni/Au plating was performed and characterized in mechanical and metallurgical point of view. Effect of annealing on Ni bump characteristics informed that the formation of crystalline nickel with $Ni_3$P precipitation above $300^{\circ}C$ causes an increase of hardness and an increase of the intrinsic stress resulting in a reliability limitation. As an interconnection material, modified ACFs composed of nickel conductive fillers for electrical conductor and non-conductive inorganic fillers for modification of film properties such as coefficient of thermal expansion(CTE) and tensile strength were formulated for improved electrical and mechanical properties of ACF interconnection. The thermal fatigue life of ACA/F flip chip on organic board limited by the thermal expansion mismatch between the chip and the board could be increased by a modified ACA/F. Three ACF materials with different CTE values were prepared and bonded between Si chip and FR-4 board for the thermal strain measurement using moire interferometry. The thermal strain of ACF interconnection layer induced by temperature excursion of $80^{\circ}C$ was decreased with decreasing CTEs of ACF materials.

• Journal of Korea Entertainment Industry Association
• /
• v.14 no.6
• /
• pp.279-287
• /
• 2020

This study aims to put forth an efficient way of improving body shapes by examining the effects of deep tissue massage and illite-combined deep tissue massage on body shape changes, and identifying body shape changes when applying each method. This study targeted twenty women in their thirties, and ten separate subjects were placed in different groups. Then deep tissue massage and illite-combined deep tissue massage were performed once a week, for a total of eight weeks. Moire Topography was applied before the experiments, four weeks later and eight weeks later to compare changes in spinous process inclination, shoulders and hips. The data collected were analyzed using SPSS v. 21.0, and the study results are as follows. In relation to general characteristics of the subjects, professionals occupied the highest proportion of them, and 90% of them were married. Here, 77.8% of them had experience in giving birth, and 78.6% of them chose natural birth. In addition, 57.1% of the subjects holding a majority had two children. When measuring spinous process inclination, shoulders and hips in the illite-combined deep tissue massage group and in the deep tissue massage group before the experiments, the illite-combined deep tissue massage group showed somewhat higher values in every area than the deep tissue massage group, but no statistically significant differences were not found, which means the homogeneity existed between them. When comparing body shape changes between the two massage methods, there were significant differences(p<.05, p<.01), because the illite-combined deep tissue massage group showed a much higher decline in spinous process inclination, shoulders and hips than the deep tissue massage group. This implies illite-combined deep tissue massage was more effective in improving body shapes than deep tissue massage. Therefore, illite-combined deep tissue massage is considered to be helpful in improving body shapes, and it is anticipated that this massage method can be used in relevant fields, including the skin care industry.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.7
• /
• pp.205-215
• /
• 2013

In digital imaging system, Bayer pattern is widely used and the observed image is degraded by optical blur during image acquisition process. Generally, demosaicing and deblurring process are separately performed in order to convert a blurred Bayer image to a high resolution color image. However, the demosaicing process often generates visible artifacts such as zipper effect and Moire artifacts when performing interpolation across edge direction in Bayer pattern image. These artifacts are emphasized by the deblurring process. In order to solve this problem, this paper proposes a deblurring algorithm combined with edge directional color demosaicing method. The proposed method is consisted of interpolation step and region classification step. Interpolation and deblurring are simultaneously performed according to horizontal and vertical directions, respectively during the interpolation step. In the region classification step, characteristics of local regions are determined at each pixel position and the directionally obtained values are region adaptively fused. Also, the proposed method uses blur model based on wave optics and deblurring filter is calculated by using estimated characteristics of local regions. The simulation results show that the proposed deblurring algorithm prevents the boosting of artifacts and outperforms conventional approaches in both objective and subjective terms.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.11
• /
• pp.1999-2010
• /
• 1992

The fixed slab analogy device which can measure stress intensity factors(S.I.F) experimentally by slab analogy theory is developed in this paper. The margin of errors resulted from the new testing apparatus are between 0.02% and 8.25%. Therefore, it is assured that this one can be effectively used for the more accurate measurement of S.I.F.( $k_{I}$, $k_{I I}$) than conventional apparatus. The pitch of master grating used in this experiment is 0.1mm It is known that the ratio of the distance from crack tip to the crack length on obtaining the accurate stress intensity factor is between 0.4 and 0.7. The optimum curvature radius of slab is about 125mm. The thickness of slab(plate) used in the fixed slab analogy device is 0.05mm(P.V.C. ; E = 64 MN/ $m^{2}$, .nu.=0.38), which is proved to be suitable for the test. The optimum material for the frame(slab`s external boundary) is a alloy tool steel(SKS 5) plate and its thickness is 1mm. In this research, the rigid cracks are directly bonded to the slab surface by cyanoacrylate adhesive for the easiness of slab making and conformity to the practical crack figure. The material of rigid crack is thin steel plate. It is expected that the developed method can be used effectively for the analysis of $k_{I}$ and $k_{I I}$ of arbitrary shaped or distributed cracks.cks.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.6
• /
• pp.598-603
• /
• 2019

Three-dimensional shape measurement technology is used in various industries. Among them, optical three-dimensional shape measurement techniques based on the optical trigonometry are mainly used in the field of semiconductor product inspection, where large quantities of three-dimensional shape measurements are made daily in factories and fine measurements are also required. The light source and the drive circuit, which are components of three-dimensional measurement equipment based on this optical trigonometry, produce heat generated by prolonged operation, and may be exposed to conditions where the ambient temperature is not constant, resulting in temperature-induced measurement errors. In this study, the compensation method of the Thermal Errors for Phase Measuring Profilometry is proposed. Three-Dimensional Shape Measurement Equipment based on Phase Measuring Profilometry is implemented to measure the height of an object and ambient temperature for 10 Hours, and a regression line was obtained line by making simple linear regression using measured temperature and height values. This regression line was used to correct the error of the height measurement according to the temperature, and thermal error was from 139.88 um(Micrometer) to 13.12 um.

• Journal of Sasang Constitutional Medicine
• /
• v.8 no.1
• /
• pp.101-186
• /
• 1996

The clinical application of constitutional Diagnosis is the most important part of Sasang constitutional medicine. It has been studied in various way. However, the study of morphologic characteristics on the face is applied for the first time. For quantitative analysis of the correlation between the sasang constitution and the shape of the face, the head-facial part of 170 cases were measured by Martin's measurement and analysis of a) the measurement value of height and the component ratio from the Gnathion to each part of face by constitution. b) the measurement value of depth and the component ratio from T-projected to each part of the face by constitution. c) the measurement value of breadth and component ratio between each parts of the facial breadth by constitution. d) the ratio of square on every part of face by constitution. e) the characteristics on each part of the face by constitution. f) the contour line of the forehead. g) the result of discriminant analysis about the constitution. Authors obtained the results from the study as follows; 1. The characteristics of Taeum-IN (1) The measurement value of Height, Breadth, T-Projected had a tendency to maximum value in general. (2) The value of lower opthal height and the square of lower opthal part was maximum. (3) The value of Pronasal T-projected length and Subnasal T-projected length was minimum, so Taeum-In has characteristics of depression in middle face, nasal part. (4) In the ratio of Breadth, T-Projected, T-Projected was minimum. (5) It was maximum that the square of nose, Alare, Middle face, Lower face and it was minimum that the square of eye. The square of nose, Alare, Middle facc, Lower face was maximum and the square of eye was minimum. (6) The curvature of the eyebrow was minimum. (7) The projection of jaw (Pogonion T-projection length) was maximum. (8) The breadth of eye was minimum. (9) There was a tendency that the projection of the forehead to the right in general. 2. The characteristics of Soeum-In (1) In all cases of projected length the measurement value was minimum. (2) The value of lower opthal height and the square of lower opthal part was minimum. (3) By the Pupulare T-projected length, the value of Pronasal T-projected length and Subnasal T-projected length was minimum, so the Soeum In's face shape is flat. (4) The square of eye, mouth, forehead was maximum and the square of nose, Alare, Middle face, Lower face was minimum. (5) The curvature of the eyebrow was maximum. (6) The projection of mouth was minimum. (7) The jaw was flat. (8) The breadth of eye was maximum. (9) There was a tendency that the projection of the forehead to the left in general. 3. The characteristics of Soyang-In. (1) In most cases of 고경 length the measurement value was minimum. (2) By the Pupulare T-projected length, each ratio of projected length was maximum, so the Soyang-In's face shape has many protrusions (3) In the ratio of Breadth, T-Projected, T-Projected was maximum. (4) The square of mouth was minimum. (5) The inclination of the forehead was minimum. (6) The projection of mouth was maximum. (7) The breadth of eye was minimum. (8) There was a tendency that the projection of the forehead to the left in general. (9) The middle face was protruded. 4. Discriminant about the constitution. According to the result of discriminant, the accuracy probability of discriminant was 85.58% in total and Taeum-In was 90.5%, Soeum-In was 70.8%, Soyang-In was 89.5%. The accuracy probability of discriminant about 3 constitutional group increased by 49.03% than the accident probility 36.55% 5. Suggestion (1) The study which gather and analysis the data should be continued. (2) The study which subdivide the characteristics of each part of the face by the constitution should be continued. (3) The analysis method about Moire should be supplement. (4) The study about the morphologic characteristics of the whole body should be continued. (5) Computer program of constitution diagnosis should be developed. (6) To increase utility of this method, the measurement should be automation.