• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2012년도 춘계 종합학술대회 논문집
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• pp.329-330
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• 2012

• Structural Engineering and Mechanics
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• 제52권4호
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• pp.739-753
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• 2014

There have been many packages that can be employed to analyze plane frames. However, because most structural analysis packages suffer from closeness of system, it is very difficult to integrate it with an optimization package. To overcome the difficulty, we proposed a possible alternative, DAMDO, which integrate Design, Analysis, Modeling, Definition, and Optimization phases into an integrative environment. The DAMDO methodology employs neural networks to integrate structural analysis package and optimization package so as not to need directly to integrate these two packages. The key problem of the DAMDO approach is how to generate a set of reasonable random designs in the first phase. According to the characteristics of optimized plane frames, we proposed the ratio variable approach to generate them. The empirical results show that the ratio variable approach can greatly improve the accuracy of the neural networks, and the plane frame optimization problems can be solved by the DAMDO methodology.

• 한국군사과학기술학회지
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• 제14권3호
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• pp.388-396
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• 2011

Mission Equipment Package(MEP) system is a collection of avionic components that are integrated to perform the mission of the Korean Utility Helicopter(KUH). MEP system development is classified mission-critical embedded system but KUH MEP system developed including flight-critical data implementation. It is important to establish the good development and verification process for the successful system development. This paper describe the development and verification process in each phase for the KUH MEP system. MEP system design is verified through the qualification test, system failure test and compatibility test in System Integration Laboratory(SIL).

• ETRI Journal
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• 제32권4호
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• pp.614-617
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• 2010

For an antenna-in-package (AiP), via holes are used to connect the antenna ground and system ground. In this letter, a dual-frequency AiP with a U-slot embedded in the patch is proposed. By properly arranging three via holes under the non-radiating edge, an AiP with two resonant frequencies is realized. Then a U-slot is embedded in the patch to further improve the bandwidth of the AiP. To validate the proposed design, an AiP with the bandwidth of 4.49% at 2.45 GHz and 6.02% at 5.32 GHz is achieved and fabricated. The measured results agree with the simulated results.

• 전기학회논문지
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• 제57권4호
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• pp.653-659
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• 2008

This paper describes the design of high power transistor packages using high power chip transistor dies, chip capacitors and a new wire bonding technique. Input impedance variation and output power performances according to wire inductance and resistance for internal matching are also discussed. A multi crossing type(MCT) wire bonding technique is proposed to replace the conventional stepping stone type(SST) wire bonding technique, and eventually to improve the output power performances of high power transistor packages. Using the proposed MCT wire bonding technique, it is possible to design high power transistor packages with highly improved output power compared to SST even the package size is kept to be the same.

• 한국포장학회지
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• 제20권1호
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• pp.1-6
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• 2014

신선 농산물의 필름포장은 적정의 저온저장 시에는 적정 변형기체조건 유지로 품질유지가 양호하나, 상대적으로 온도가 높은 판매유통단계에서는 적정조건의 유지가 어려워 품질손실이 발생한다. 저온저장과 판매유통단계에서 농산물 주위에 적정 변형기체(modified atmosphere, MA)조성을 유지하는 개별(1차)포장/2차 포장의 결합 및 해체 개념을 설계한 마스터 포장 시스템이 최근에 제안되고, 단감, 큰느타리 버섯, 밤, 딸기에 대해서 적용된 바 있다. 온도에 따라 다른 농산물의 호흡과 포장의 기체이동 현상의 상호관계를 이용한 마스터 포장 시스템의 개념을 체계화하고, 적정 MA 유지를 위한 설계변수의 조합을 살펴보았다. 바람직한 포장기체조성을 형성 유지할 수 있는 마스터 포장 시스템의 설계를 위한 수학적 모델이 제시되었다. 아울러 마스터 포장 시스템의 이점과 함께 적용을 위한 한계에 대해서 논의하였다. 마스터 포장 시스템의 적용 확대를 위한 미래의 연구방향을 제시하였다.

• 마이크로전자및패키징학회지
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• 제9권2호
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• pp.33-38
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• 2002

패키지는 전기적인 특성에 있어서 적은 삽입손실과 반사손실 특성이 요구된다. 따라서 이러한 고주파 전송 특성이 우수한 패키지를 설계하기 위하여 본 논문에서는 LTCC (Low Temperature Cofired Ceramic) 기술을 이용한 세라믹 패키지를 설계하였고, 유한요소법(FEM: Finite Element Method)을 이용하여 DC~30 GHz에서 해석하였다. 해석 결과, 설계된 패키지 급전구조는 30 GHz까지 삽입손실과 반사손실이 각각 0.32 dB, 16.8 dB 이내의 양호한 특성을 얻었다. 따라서 본 논문에서 설계된 세라믹 패키지는 MMIC (Monolithic Microwave Integrated Circuit) 모듈 개발에 효과적으로 활용될 수 있으리라 기대된다.

• 마이크로전자및패키징학회지
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• 제8권2호
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• pp.37-42
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• 2001

The BGA package has been the area array package of choice for several years. Recently, the transition has been to finer pitch configurations called Chip Scale Packages (CSP). Several of these package types are available at 0.5 mm pitch. requiring surface mount assemblers to evaluate and optimize various elements of the assembly process. This presentation describes the issues associated with making the transition from BGA to CSP assembly. Areas addressed will include the accuracy of pick and place equipment, printed wiring board lines and spaces, PWB vias, in-circuit test issues, solder paste printing, moisture related factors, rework and reliability. The transition to 0.5 mm pitch requires careful evaluation of the board design, solder paste selection, stencil design and component placement accuracy. At this pitch, ball and board pad diameters can be as small as 0.25 mm and 0.20 mm respectively. Drilled interstitial vias are no longer possible and higher ball count packages require micro-via board technology. The transition to CSP requires careful evaluation of these issues. Normal paste registration and BGA component tolerances can no longer achieve the required process levels and higher accuracy pick and place machines need to be implemented. This presentation will examine the optimization of these critical assembly operations, contrast the challenges at 0.5 mm and also look at the continuation of the process to incorporate smaller pitch flip chip devices.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2001년도 Proceedings of 6th International Joint Symposium on Microeletronics and Packaging
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• pp.27-34
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• 2001

The BGA Package has been the area array package of choice for several rears. Recently, the transition has been to finer pitch configuration called Chip Scale Packages (CSP). Several of these package types are available at 0.5 mm pitch, requiring surface mount assemblers to evaluate and optimize various elements of the assembly process. This presentation describes the issues associated with making the transition from BGA to CSP assembly. Areas addressed will include the accuracy of pick and piece equipment, printed wiring board lines and spaces, PWB vias, in-circuit test issues, solder paste printing, moisture related factors, rework and reliability. The transition to 0.5 mm pitch requires careful evaluation of the board design, solder paste selection, stencil design and component placement accuracy. At this pitch, ball and board pad diameters can be as small as 0.25 mm and 0.20 mm respectively. Drilled interstitial vias are no longer possible and higher ball count packages require micro-via board technology. The transition to CSP requires careful evaluation of these issues. Normal paste registration and BGA component tolerances can no longer achieve the required process levels and higher accuracy pick and place machines need to be implemented. This presentation will examine the optimization of these critical assembly operations, contrast the challenges at 0.5 mm and also look at the continuation of the process to incorporate smaller pitch flip chip devices.

• 패션비즈니스
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• 제27권2호
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• pp.108-123
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• 2023

Recent increase of eco-conscious trends and pleasure from Do It Yourself (DIY) activities have led to a surge in sales of package products bundling together clothing patterns and raw materials. However, a well-structured market system is yet to be established. We surveyed 460 women with sewing as a hobby who had purchased these DIY clothing pattern packages. The survey revealed that majority of respondents had their hobby for over five years. Choosing the right fabric to match clothing patterns presented a common challenge. Most participants owned a sewing machine and an overlocker, with price being the primary concern when purchasing a package. For guidance during the sewing process, participants preferred print materials featuring real-life images. Those with less sewing experience leaned towards video tutorials. Items of interest or those commonly created included blouses, shirts, and dresses. Desire for further learning in sewing and pattern-making was prominent, with a clear preference for online classes. Several strategies are recommended to enhance the appeal of DIY clothing package products, including broadening range of packages that incorporate fabric, offering supplementary educational resources to improve users' skills, implementing affordable pricing structures, supplying comprehensive creation guidelines, and making available design modification guides. These considerations could significantly boost customer satisfaction. This research intends to lay groundwork for understanding DIY clothing creation market, ultimately fostering production of highly desirable products. Insights of this study will prove instrumental in refining product development and devising effective marketing tactics, leading to a more rewarding consumer experience.