• Journal of the Microelectronics and Packaging Society
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• v.18 no.3
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• pp.45-52
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• 2011

It is known that test methods to evaluate solder joint reliability are die shock test, die shear test, 3points bending test, and thermal shock test. The present study investigated the effects of failure mode on 3 types (as-reflowed, $85^{\circ}C$/85%RH treatment, and $150^{\circ}C$/10hr aging) of solder joints for flip-chip BGA package by using various test methods. The test methods and configurations are reported in detail, i.e. die shock, die shear, 3points bending, and thermal shock test. We focus on the failure mode of solder joints under various tests. The test results indicate that die shock and die shear test method can reveal brittle fracture in flip-chip ball grid array (FCBGA) packages with higher sensitivity.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.2
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• pp.35-41
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• 2011

Recently, board level solder joint reliability performance of IC packages during drop impact becomes a great concern to semiconductor and electronic product manufacturers. The handheld electronic products are prone to being dropped during their useful service life because of their size and weight. The IC packages are susceptible to solder joint failures, induced by a combination of printed circuit board (PCB) bending and mechanical shock during impact. The board level drop testing is an effective method to characterize the solder joint reliability performance of miniature handheld products. In this paper, applying the JEDEC (JESD22-B111) standard present a finite element modeling of the FBGA. The simulation results revealed that maximum stress was located at the outermost solder ball in the PCB or IC package side, which consisted well with the location of crack initiation observed in the failure analysis after drop reliability tests.

• Korean Journal of Computational Design and Engineering
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• v.19 no.4
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• pp.402-409
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• 2014

Presented in this paper is a scheduling method for semiconductor backend process considering the backward pegging. It is known that the pegging for frontend is a process of labeling WIP lots for target order which is specified by due date, quantity, and product specifications including customer information. As a result, it gives the release plan to meet the out target considering current WIP. However, the semiconductor backend process includes the multichip package and test operation for the product bin portion. Therefore, backward pegging method for frontend can't give the release plan for backend process in semiconductor. In this paper, we suggest backward pegging method considering the characteristics of multichip package and test operation in backend process. And we describe the backward pegging problem using the examples.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.60-67
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• 2013

Test cost reduction is necessary to test a complex System-on-a-Chip(SoC) which adopts various Intellectual Properties (IP). In this paper, test architecture with low pin count which is able to IP-based SoC test, using IEEE Std. 1149.7 and IEEE Std. 1500, is proposed. IEEE Std. 1500 provides independent access mechanism for each IP in IP-based SoC test. In this paper, just two test pins are required by composing that these independent access mechanism can be controlled by IEEE Std. 1149.7. The number of Chips which are tested at the same time is increased by reducing required test pin count at wafer and package level test, and consequently the overall manufacturing test cost will be reduced significantly.

• Journal of the Korean Data and Information Science Society
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• v.17 no.1
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• pp.41-52
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• 2006

Because most common assumption is normality in statistical analysis, testing normality is very important. The Q-Q plot is a powerful tool to test normality with full samples in statistical package. But the plot can't test normality in type-II censored samples. This paper proposed the modified the Q-Q plot and the modified normalized sample Lorenz curve(NSLC) for normality test in the type-II censored samples. Using the two Hodgkin's disease data sets and the type-II censored samples, we picture the modified Q-Q plot and the modified normalized sample Lorenz curve.

• International Area Studies Review
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• v.16 no.1
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• pp.53-74
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• 2012

The bundling of multiple products/services at a set price has become a popular marketing strategy. However, little is known on how effects of bundling strategy influence tourists' evaluation of tour packages. Tourists evaluate a tour package based on the trade-off between the perceived benefits and costs involved in purchasing the tour package. In other words, the perceived value of the tour package influenced whether tourists to purchase a tour package or not. This study tested a tour package based on the theory of bundling, taking a moderating approach with perceived value. The data for this study wascollected by subjects who live Seoul Metropolitan Area and Gyeonggi Province and 4234 respondents, potential tourists to northeastern U.S.A/Canada. Results show that bundling taken by travel agencies include how many product items to put in a tour package and what degree of discount for the tour package. Also explaining functional relationship among product items in the tour package. Result show that tourists expect a discount, large or small, from purchasing a tour package. And the larger the number of products in a tour packages, the larger the discount size, and low functional relationship among items tourists expect to get.

• The Korean Journal of Applied Statistics
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• v.35 no.5
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• pp.579-591
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• 2022

Functional data is collected in various fields. It is often necessary to test whether there are differences among groups of functional data. In this case, it is not appropriate to explain using the point-wise ANOVA method, and we should present not the point-wise result but the integrated result. Various studies on functional data analysis of variance have been proposed, and recently implemented those methods in the package fdANOVA of R. In this paper, I first explain ANOVA and multivariate ANOVA, then I will introduce various methods of analysis of variance for univariate and multivariate functional data recently proposed. I also describe how to use the R package fdANOVA. This package is used to test equality of weekly temperatures in Seoul and Busan through univariate functional data ANOVA, and to test equality of multivariate functional data corresponding to handwritten images using multivariate function data ANOVA.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6603-6608
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• 2014

Cervical cancer is one of the leading causes of cancer in women worldwide. One way by which the incidence of this malignant disease can be minimized is by imparting knowledge through health education. This study aimed at developing an educational package on cervical cancer (EPCC) and determining its effectiveness in terms of significant increase in knowledge of rural women regarding cervical cancer. A one group pre-test, post-test design was adopted. Thirty rural women were selected using a convenient sampling method. Data were collected using a demographic questionnaire and a structured knowledge questionnaire developed by the researchers. The EPCC was designed for a duration of one hour and 10 minutes. The structured knowledge questionnaire was first administered as the pre-test, following which knowledge on cervical cancer was imparted using the EPCC. On the 8th day, the post-test was administered. Data were analyzed using descriptive and inferential statistics. The mean post-test knowledge score of the women regarding cervical cancer was significantly higher than that of their mean pre-test score, indicating that the EPCC was effective in improving the knowledge of rural women on cervical cancer. The association between pre-test knowledge scores and selected demo-graphic variables were computed using chi-square test showed that pre-test knowledge score of the women regarding cervical cancer was independent of all the socio-demographic variables. It was concluded that the EPCC is effective in improving the knowledge of women, regarding cervical cancer. Since the prevalence of cervical cancer is high, there is an immediate need to educate women on prevention of cervical cancer.

• Journal of Biosystems Engineering
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• v.30 no.2 s.109
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• pp.89-94
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• 2005

The compression strength of corrugated fiberboard container for packaging the agricultural products rapidly decreases because of various environmental conditions during distribution of unitized products. Among various environmental conditions, the main factors affecting the compression strength of corrugated fiberboard are absorption of moisture, long-term accumulative load, and fatigue caused by shock and vibration. An estimated rate of damage for fruit during distribution is about from 30 to 40 percent owing to the shock and vibration. This study was carried out to characterize the durability of corrugated fiberboard container for packaging the fruit and vegetables under simulated transportation environment. The vibration test system was constructed to simulate the land transportation using truck. After the package with corrugated fiberboard container was vibrated by vibration test system at various experimental conditions, the compression test for the package was performed. The compression strength of corrugated fiberboard container decreased with loading weight and vibrating time. The multiple nonlinear regression equation for predicting the decreasing rate of compression strength of corrugated fiberboard containers were developed using four independent variables such as input acceleration level, input frequency, loading weight and vibrating time. The influence of loading weight on the decreasing rate of corrugated fiberboard container was larger than other variables.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1479-1487
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• 2011

In the field of the entire electronic component industry including mobile IT products, the importance of a versatile package with the multifunctional or high capacity memories is gradually increased. Multi Chip Package which has several chips in a single package is frequently used for that purpose. In MCP, epoxy adhesive films play a major role in adhesion between the chips or between chip and substrate. A series of silane coupling agents with a functional group such as epoxy, amine, mercaptan, and isocyanate were applied to the epoxy adhesives and material properties such as wettability and reliability of the adhesives were investigated. From the results, the silane coupling agent with an epoxy functional group showed highest wettability and peel strength in epoxy adhesive. For those reasons, it lead to a superior reliability in the epoxy adhesive against interfacial fracture behaviors through moisture resistance test.