• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.265-271
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• 2008

TCP(Tape Carrier Package), COG (Chip On Glass), COF(Chip On Film) are three methods for connecting LDI(LCD Driver IC) with LCD panels. Especially COF is growing its portion of market place because of low cost and fine pitch correspondence. But COF has a problem of the lead broken failure in LCD module process and the usage of customer. During PCB (Printed Circuit Board) bonding process, the mismatch of the coefficient of thermal expansion between PCB and D-IC makes stress-concentration in COF lead, and also D-IC bending process during module assembly process makes the level of stress in COF lead higher. As an affecting factors of lead-broken failure, the effects of SR(Solder Resister) coating on the COF lead, surface roughness and grain size of COF lead, PI(Polyimide) film thickness, lead width and the ACF(Anisotropic Conductive Film) overlap were studied, The optimization of these affecting manufacturing processes and materials were suggested and verified to prevent the lead-broken failure.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.823-825
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• 1996

This paper proposes a preventive maintenance scheduling system which is a user-friendly decision-making support system. The objective of the development of the package is to supply KEPCO's working experts with a useful tool for gaining a practical maintenance schedule. This program based on the MS Windows is made up of two main modules. The first is an interactive decision-making support module(IDSM). The main objective of this module is to provide various useful text and graphic information to users, and enable practicing engineers with sensitivity analysis of a targeting maintenance schedule. The second is a mathematical optimization module(MOM). In this module, the objective function of levelizing net reserve ratio with daily time-increment is optimized using the relaxation method.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.4
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• pp.243-250
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• 2001

This paper presents the structure of a $\mu$Spring package, its fabrication process and an analysis of its electrical characteristics compared to that of a $\mu$BGA. It was found that both $\mu$BGA and $\mu$Spring packages provide with outstanding high speed signal transmission characteristics due to their lower inductance of package interconnection lines, smaller than half of inductance of TSOP package lines. Even the worst case substrate trace of a Rambus DRAM $\mu$Spring package yields the line inductance of 2.9nH, which provides with 25% margin compared to the Rambus DRAM specification of 4nH. The fabrication cost of $\mu$Spring package is lower than that of $\mu$BGA by 50%, passes 1000 thermal cycles, meets JEDEC Level 1 specification whereas $\mu$BGA does not, and thereby yields high reliability and strong competing power.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.96-99
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• 2000

We presents a BGA(Ball Grid Array) package for RF circuit modules and extracted its electrical parameters. We constructed a BGA package of ITS(Intelligent Transportation System) RF module and examined electrical parameters with a HP5475A TDR(Time Domain Reflectometry) equipment and compared its electrical parasitic parameters with PCB RF circuits. With a BGA substrate of 3 $\times$ 3 input and output terminals, we have found that self capacitance of BGA solder ball is 68.6fF, self inductance 146pH, mutual capacitance 10.9fF and mutual inductance 16.9pH. S parameter measurement with a HP4396B Network Analyzer showed the resonance frequency of 1.55㎓ and the loss of 0.26dB. Thus, we may improve electrical performance when we use BGA package structures in the design of RF circuit modules.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.3
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• pp.79-84
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• 1999

The existing EMTP(Electromagnetic Transients Program) is writted by FORTRAN-77, has a closed architecture and uses a large number of code lines to satisfy requirements ranging from low level data manipulation to the actual solution mathematics which eventually become diluted and almost impossible to visualize. Thus has a difficulty in the development and maintenenace of its program module. This paper proposes a new design idea suitable (or a re-development of EMTP using the MATLAB and VISUAL-C++, which presents the development of the new EMTP package is operated in the window environment. The package has the GUI(Graphic User Interface) ability, and the MATLAB computation engine for an analysis of a transient state in an electric circuit.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.1
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• pp.57-63
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• 2015

Recently, LED is widely used in the kinds of display devices or lighting. In this paper, we fabricated LED chamber light for naval vessels to replace to conventional chamber light using incandescent lamp. The LED package of chamber light was designed with luminous intensity of 5.5 cd, color temperature of $6,000{\pm}500K$, forward voltage of 3~3.2 V and input current of 60 mA. A LED module was composed of 36 LED packages and metal PCB. The VF and luminous intensity of LED package were getting down when temperature increased. The temperature of LED chamber light was measured by changing the number of LED package and applied current for one hour when an electric current flow. The heat transfer capability have been improved by using metal PCB. The power consumption of LED chamber light reduced by 86% compared to the conventional chamber light using incandescent lamp.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2151-2161
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• 2021

Nuclear data (ND) sensitivity and uncertainty (S/U) quantification in shielding applications is performed using deterministic and probabilistic approaches. In this paper the validation of the newly developed deterministic program package ASUSD (ADVANTG + SUSD3D) is presented. ASUSD was developed with the aim of automating the process of ND S/U while retaining the computational efficiency of the deterministic approach to ND S/U analysis. The paper includes a detailed description of each of the programs contained within ASUSD, the computational workflow and validation results. ASUSD was validated on two shielding benchmark experiments from the Shielding Integral Benchmark Archive and Database (SINBAD) - the fission relevant ASPIS Iron 88 experiment and the fusion relevant Frascati Neutron Generator (FNG) Helium Cooled Pebble Bed (HCPB) Test Blanket Module (TBM) mock-up experiment. The validation process was performed in two stages. Firstly, the Denovo discrete ordinates transport solver was validated as a standalone solver. Secondly, the ASUSD program package as a whole was validated as a ND S/U analysis tool. Both stages of the validation process yielded excellent results, with a maximum difference of 17% in final uncertainties due to ND between ASUSD and the stochastic ND S/U approach. Based on these results, ASUSD has proven to be a user friendly and computationally efficient tool for deterministic ND S/U analysis of shielding geometries.

• Journal of the Korean Data and Information Science Society
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• v.17 no.2
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• pp.395-400
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• 2006

For lab statistics the statistical package SAS is usually used in PC environment. But most Universities in Korea have bought 'Academic Initiative Package chair licence', which allows to install SAS to student lab PCs only. Most students are hardly able to afford to purchase a licence for use of SAS in their PCs at home or other places than school. It would be very convenient to have a web-based SAS system, physically located inside a campus, which university students can use through internet. In this paper we report the web-based SAS system implemented for the lab purpose of Yeungnam University using SAS/Intrnet module. We overcome some Server-Client environmental difficulties not allowing use of the SAS command 'infile' by implementing modules with PHP language. In the system, users can see and execute some basic SAS sample codes by clicking buttons, which makes students feel comfy in SAS programming.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.7
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• pp.1-8
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• 2011

The high efficiency tubular LED lamp has been developed. But, it occurs optical losses in consists of LED package, module, diffuser etc.. By Measuring the tubular LED lamp's luminous flux, we compared and analyzed about the effect of optical losses for each component and actually using measured luminous intensity distribution data, illuminance distribution was simulated by Relux. Optical losses are 24[%] from LED package to luminaire and the tubular LED lamp can be replaced with fluorescent lamp. In this paper, we could provide data for optimum lighting design by analyzing the optical characteristics for developing and propagating the tubular LED lamp.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.4
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• pp.380-387
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• 2009

The reliability concerns of solder interconnections in flip chip PBGA packages are produced mainly by the mismatch of coefficient of thermal expansion(CTE) between the module and PCB. Finite element analysis has been employed extensively to simulate thermal loading for solder joint reliability and deformation of packages in electronic packages. The objective of this paper is to study the thermo-mechanical behavior of FC-PBGA package assemblies subjected to temperature change, with an emphasis on the effect of the finite element model, material models and temperature conditions. Numerical results are compared with the experimental results by using $moir{\acute{e}}$ interferometry. Result shows that the bending displacements of the chip calculated by the finite element analysis with viscoplastic material model is in good agreement with those by $moir{\acute{e}}$ inteferometry.