• Particle and aerosol research
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• v.9 no.4
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• pp.253-260
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• 2013

For a vertical atmospheric aerosol distribution measurement, a very compact and light particle sampling package is developed. This package includes a compact optical particle counter (Hy-OPC), a light and small condensation particle counter (Hy-CPC), sensors (GPS, wind velocity, temperature, humidity), and a communication and system control board. This package is attached to He balloon and the altitude is controlled by a winch. Using this system the vertical particle size distribution was measured. The test results showed that the ground base atmospheric particle measurement result may be a lot different from that high above the ground.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.2
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• pp.122-127
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• 2018

In an attempt to estimate the life projection of LED packages, IESNA published a paper regarding an LED package measurement test method in 2008, and a life projection technical document in 2011, to be used for LED life estimation. IESNA's publications regarding LED package measurement methods were functional, but they were not internationally standardized before 2017. In order to develop a standardized method, the International Standard chose to use the LM-80 as a measurement method for LED life projection in their publication in 2017. Many projection methods have been discussed by the IEC Technical Committee 34 working group, including the method using an exponential function, which reflects lumen degradation characteristics well. This study is designed to explore alternative LED package life estimation methods using an exponential function with statistical analysis, other than the one suggested by the International Standard.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.11
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• pp.1646-1655
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• 2004

A description of the basic principles of moire interferometry leads to the design of a eight-mirror four-beam interferometer for obtaining fringe patterns representing contour-maps of in-Plane displacements. The technique is implemented by the optical system using an environmental chamber for submicro-displacement mesurement. In order to estimate the reliability and applicabili쇼 of the system developed, the measurement of coefficient of thermal expansion (CTE) for a aluminium block is performed. Consequently, the system is applied to the measurement of thermal deformation of a WB-PBGA package assembly. Temperature dependent analyses of global and local deformations are presented to study the effect of the mismatch of CTE between materials composed of the package assemblies. Bending displacements of the packages and average strains of solder balls are documented. Thermal induced displacements calculated by FEM agree quantitatively with experimental results.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.565-570
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• 2004

The construction Progress is widely used 3s a critical index for effective project management. However, the methods, structure, data, and accuracy of progress measurement may vary depending on specific characteristics of the project, organization, or location. Even in an organization, different projects may utilize different measurement methods to effectively achieve their own management purpose. The excessive effort required to manipulate very detailed progress data is also an issue Therefore the purpose of this study is to dove]op an automated progress measurement model utilizing standard progress measurement package (SPMP).

• Electrical & Electronic Materials
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• v.10 no.6
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• pp.519-527
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• 1997

The micro crack was occurred where the stress concentrated by the thermal stress which was induced during the cooling period after molding process or by the various reliability tests. In order to estimate the possibility of development from inside micro crack to outside fracture, the fracture toughness of EMC should be measured under the various applicable condition. But study was conducted very rarely for the above area. In order to provide a was to decide the fracture resistance of EMC (Epoxy Molding Compound) of plastic package which is produced by using transfer molding method, measuring fracture is studied. The specimens were made with various EMC material. The diverse combination of test conditions, such as different temperature, temperature /humidity conditions, different filler shapes, and post cure treatment, were tried to examine the effects of environmental condition on the fracture toughness. This study proposed a way which could improve the reliability of LOC(Lead On Chip) type package by comparing the measured $J_{IC}$ of EMC and the calculated J-integral value from FEM(Finite Element Method). The measured $K_{IC}$ value of EMC above glass transition temperature dropped sharply as the temperature increased. The $K_{IC}$ was observed to be higher before the post cure treatment than after the post cure treatment. The change of $J_{IC}$ was significant by time change. J-integral was calculated to have maximum value the angle of the direction of fracture at the lead tip was 0 degree in SOJ package and -30 degree in TSOP package. The results FEM simulation were well agreed with the results of measurement within 5% tolerance. The package crack was proved to be affected more by the structure than by the composing material of package. The structure and the composing material are the variables to reduce the package crack.ack.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.4
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• pp.61-70
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• 1998

The electrical performance of a package is extremely important for high speed digital system operations. CSP(chip scale package) is known to have better electrical performance than the convnetional packages. In this paper, the electrical performance of the BLP(bottom leaded plastic) package, a kind of CSP, has been alayzed by both simulation and real measurement. The electrical perfdormance of a BLP was compared with that of the conventioanl TSOP(thin small outline package). The leadinductanceand lead capacitance were used for the comparison purposes. The new BLP design provides much better electrical performance that TSOP package. It has about 40% favorable parameter values.

• Proceedings of the Korea Association of Information Systems Conference
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• 2001.12a
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• pp.158-165
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• 2001

The certification of software products can provide a greater level of acceptance and feeling of security to customers of these products. This paper presents a certification method for the quality of package software. First of all, the evaluation criteria are derived from ISO/1EC 9126 and 12119 standards, and then the evaluation module are designed considering the measurement scale type. The results can be applied to construct the certification scheme of software product quality for the commercial purpose.

• Proceedings of the Safety Management and Science Conference
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• 2002.05a
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• pp.193-197
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• 2002

The certification of software products can provide a greater level of acceptance and feeling of security to customers of these products. This paper presents a certification method for the quality of package software. First of all, the evaluation criteria are derived from IS0/1EC 9126 and 12119 standards, and then the evaluation module are designed considering the measurement scale type. The results can be applied to construct the certification scheme of software product quality for the commercial purpose.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.431-436
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• 2005

In this paper, We proposed the stereo image modeling using 2-dimensional images captured by the high resolution cameras to inspect the ball defects of BGA(Ball Grid Array) device. The proposed algorithm consists of the package/ball area extraction part, the FOV(Field of View) calibration part, the top point matching part, and ball height measurement part, In the package/ ball area extraction part, the package and ball areas are separately extracted in a left and right image by the extraction algerian. Through the experiment, we draw out the result.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.108-111
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• 2000

The electrical characteristics of MQFP packages have been measured in RF regime. The s-parameter of the lead frame has been measured using the test fixture on which the do-capped package was mounted. A simple lumped equivalent circuit modeling of the lead frame and the test fixture can provide reasonable model parameters up to the frequency of 200 MHz.