• Journal of the Korean Solar Energy Society
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• v.29 no.1
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• pp.58-63
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• 2009

In this paper, the power loss due to PV module mismatch in PV string is analyzed and a mismatch compensation method is proposed to improve the efficiency of PV system. The analysis of mismatch loss using PV model simulation reveals that the mismatch module may decrease the total efficiency because the MPPT function of power conditioner make the PV system operate at the local maximum point. The mismatch loss can be severe if the maximum power point current of mismatch module is less than that of string. The proposed compensation method which is simply implemented with a buck type converter shows the possibility to remove the mismatch loss. The effectiveness of the analysis and compensation method is verified by a prototype experiment.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.09a
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• pp.79-94
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• 2002

Root cause -Thermal expansion coefficient mismatch -Tape warpage -Initial die crack (die roughness) Guideline for failure prevention -Optimized tape/Substrate design for minimizing the warpage -Fine surface of die backside Root cause -Thermal expansion coefficient mismatch - Repetitive bending of a signal trace during TC cycle - Solder mask damage Guideline for failure prevention - Increase of trace width - Don't make signal trace passing the die edge - Proper material selection with thick substrate core Root cause -Thermal expansion coefficient mismatch -Creep deformation of solder joint(shear/normal) -Material degradation Guideline for failure Prevention -Increase of solder ball size -Proper selection of the PCB/Substrate thickness -Optimal design of the ball array -Solder mask opening type : NSMD -In some case, LGA type is better

• Journal of the Korea Institute of Military Science and Technology
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• v.3 no.2
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• pp.213-218
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• 2000

An experimental study was performed to investigate the effect of surface temperature mismatch on measurements of skin friction using a plug-type skin friction gage mounted on the side wall of a supersonic wind tunnel. The freestream Mach number was 2.4 and Reynolds number per meter was $5.25 {\times}10^7$ with total pressure of 50 psi and total temperature of 275K. Temperature mismatch between the gage surface and surrounding wall surface was generated by hot water injection using the active temperature control system. Results of the tests showed that the temperature mismatch made sizable effects on the measurements of skin friction.

• Korean Journal of Child Studies
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• v.25 no.5
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• pp.179-191
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• 2004

An emotion inference task was used to investigate children's cognitive cuing by age, cue type, and situation-emotion fit. Subjects were 41 of 3-, and 5-year-old children from two different day-care centers in Seoul and Kyonggi province. Each child was individually interviewed with pictorial tasks. 5-year-old children demonstrated more cuing, thinking, and application responses than 3-year-old children. Particularly, they showed more situation and thinking responses in situation-emotion match than in situation-emotion mismatch. 3-year-old children showed more past-oriented responses than 5-year-old children. In the interpersonal cue story, there were more situation, past-oriented and thinking responses than in the interobjective ones. The interpersonal cue story produced more situation responses in situation-emotion match than in situation-emotion mismatch.

• The Journal of the Korea Contents Association
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• v.16 no.10
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• pp.81-95
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• 2016

This study aims to introduce a new approach to make up for the weak points in small business, to explore views of the small business employees and job-seekers on the basis of Q-Methodology. From the Q-methodology, the types of perception toward small business and their features from diverse views were drawn. The data from 33 participants were analyzed by using QUANL-PC program. The perception types were classified as four types: positive perception type, negative perception type, high evaluation about utilitarian pursuit type, neutral evaluation type. The results found that views toward small business are more positive than previous findings and perceptions were diverse beyond the dichotomy. Hence, to mitigate job mismatch, small business recruiting strategy should be provided based on diverse job-seeker types.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.3
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• pp.405-412
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• 2013

This paper reports the steady-state stresses within the heat affected zone (HAZ) of a welded straight pipe subject to creep. The creep constants and exponent are varied systematically to see the effect of various mismatches in creep properties on the steady-state creep stresses, via detailed two-dimensional finite element (FE) creep analyses. The weldments consist of the base metal and weld metal with the HAZ, which are characterized using the idealized power creep laws with the same creep exponent. The internal pressure and axial loading are considered to see the effect of the loading mode. To quantify the creep stresses, a creep mismatch factor is introduced as a function of the creep constants and exponent. It is concluded that the ratio of the section-averaged stresses for a mismatched case to those for an evenmatched case are linearly dependent on the mismatch factor. The results are compared with the FE results, including the Type IV region, as well as the R5 procedure.

• Journal of the Korean housing association
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• v.12 no.2
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• pp.133-142
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• 2001

The development of idyllic housings, is in increasing growth in the suburban areas of Seoul, presents some critical problems such as in sufficient common open space and poor living condition, which are mainly caused by disorderly designed. Through comparing planning indices of idyllic housing, this paper aims to diagnose the condition and causes of those problems and to present some basic issues on improvement direction. The causes of problems can be summarized as the blind point in regulation system, the shortness of planning elements of a housing block which includes road systems and public facilities, and the mismatch of housing type with density, on which includes road systems and public facilities, and the mismatch of housing type with density, on which hereafter improvement suggestion should be focused. And this study suggest the simulation models on an ideal idyllic housing to be applied in our forthcoming idyllic housing of Korea, which can indeed become a generalized alternative to the livable idyllic housing.

• Proceedings of the Korean Society for Language and Information Conference
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• 2007.11a
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• pp.234-240
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• 2007

This paper argues that various kinds of displaced structures in English should be licensed by a more explicitly formulated type of rule schema in order to deal with what is called weak connectivity in English. This paper claims that the filler and the gap site cannot maintain the total identity of features but a partial overlap since the two positions need to obey the structural forces that come from occupying respective positions. One such case is the missing object construction where the subject fillers and the object gaps are to observe requirements that are imposed on the respective positions. Others include passive constructions and topicalized structures. In this paper, it is argued that the feature discrepancy comes from the different syntactic positions in which the fillers are assumed to be located before and after displacement. In order to capture this type of mismatch, syntactically relevant features are handled separately from the semantically motivated features in order to deal with the syntactically imposed requirements.

• Journal of Chest Surgery
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• v.57 no.2
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• pp.217-219
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• 2024

Matching for the rhesus (Rh) blood group is currently not taken into account in the organ allocation system. However, in Rh-mismatched transplantation, the primary concern is the potential for RhD-negative recipients to develop sensitization and produce anti-D antibodies if they receive a transfusion of RhD-positive blood. It is estimated that over 80% of RhD-negative recipients may experience Rh allosensitization when exposed to RhD-positive blood, although this occurrence is less common in recipients of solid organs. In theory, RhD-negative recipients who receive organs from RhD-positive donors are at risk of alloimmunization and the production of anti-D antibodies, which could complicate future blood product transfusions. However, our understanding of the impact of donor-recipient Rh mismatch on transplant outcomes, particularly in heart transplantation, is limited. We report a case of successful Rh-mismatched heart transplantation, which was effectively managed through the use of preoperative RhD immunoglobulin and plasmapheresis.

• Journal of the Korean Regional Science Association
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• v.32 no.1
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• pp.67-82
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• 2016

This study aims to test the spatial mismatch hypothesis by exploring the relationship between income and commuting time in Seoul, Korea. For this purpose, we analyze the commuting times of individuals who commute to Seoul, using the data for the metropolitan household survey. We employed a hierarchial linear model(HLM) to capture the effects of both individual attributes and regional attributes, and their interactions. The results show that the commuting time decreases with household income controlling for the regional attributes, and the effect of income increases with the housing price of the location of a commuter's firm. This implies that the spatial mismatch holds for Seoul as follows: Lower personal income and housing affordablility extend individuals' commuting times, and the destinations' characteristics such as housing type and land use also have impacts on commuting time. These results have some policy implications for achieving social equity in terms of spatial structure of the city.