• Journal of Power System Engineering
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• v.17 no.1
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• pp.58-63
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• 2013

The aerodynamic performance of double inlet sirocco fan is strongly dependent upon the design factors of impeller and scroll. In this paper, the change of scroll size was adopted to investigate the aerodynamic performances of double inlet sirocco fan and indoor PAC. Especially, a scroll expansion angle and a cut-off clearance ratio were considered to change the scroll size. In addition, the installation depth between double inlet sirocco fan and indoor PAC was considered. As a result, the total pressure efficiency of double inlet sirocco fan shows about 62%~73% according to the change of scroll expansion angles. Moreover, the flowrate performance of indoor PAC is the best at the condition of a scroll expansion angle of 8°, an installation depth of 15 mm and a cut-off clearance ratio of 8%.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10d
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• pp.608-612
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• 2007

FOTA는 무선기능이 장착된 Mobile Device에 새로운 Software에 대한 알림기능이 도착하면, Software가 탐재된 서버에 접속하여 Software를 Download 받고, 그 Download한 Software를 Upgrade 하는 기능을 말한다. FOTA 기능을 장착하기 위해서 Mobile Device는 Delta Package의 사이즈를 최소화하기 위한 특별한 Binary 구조를 가지는데 두 Binary의 차이를 압축한 것을 Delta Package라고 부르며, Binary 사이에 Upgrade를 위한 여분의 Gap을 두어, 향후 수정된 내용이 있을 때, 수정사항을 공간 내에 포함할 수 있도록 한다. 바이너리를 구성하는 Object들이 Image내에 어떤 위치에 포함될 것인지를 결정하는 Scatter Loader에 따라, Binary의 구조 및 확장성, Delta의 크기를 결정하게 되는데, 이것은 Object의 Type이나 Scatter Loading File내에서 명시한 순서와는 관계가 없고, Execution Region의 분할 개수를 늘릴수록, 각 Object의 Dependency 별로 묶을수록 Delta Size가 작아지는 것을 알게 되었다. 이 논문에서는 위에서 제시한 조건이 Delta Size에 미치는 원인에 대해 분석하고, Scatter Loading File을 최적화시킬 수 있는 방안에 대해서 연구한다.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.72-75
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• 2009

In this paper, we have designed a novel lens for LED's package that can expend the radiation angle of LED from $120^{\circ}$ to $170^{\circ}$ successfully. At the same brightness and uniformity condition of 37" LED BLU system, using novel lens LED package can be reduced amounts of LED 40% or thickness of BLU 30% respectively. Besides, the power consumption of BLU also can be reduced 25%.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.262-263
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• 2007

In this paper, fully embedded and miniaturized diplexer has been designed, fabricated, and characterized for dual-band/mode CDMA handset applications. The size of the embedded diplexer is significantly reduced by embedding high Q circular spiral inductors and high DK MIM capacitors into low cost organic package substrate. The fabricated diplexer has insertion losses and isolations of -0.5 and -23dB at 824-894MHz and -0.7 and -22dB at 1850-1990MHz, respectively. Its size is 3.9mm$\times$3.9mm$\times$ 0.77mm (height). The fabricated diplexer is the smallest one which is fully embedded into low cost organic package substrate.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.2
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• pp.75-84
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• 2005

This research is to design a high performance NAND-type flash memory package with a smart buffer cache that enhances the exploitation of spatial and temporal locality. The proposed buffer structure in a NAND flash memory package, called as a smart buffer cache, consists of three parts, i.e., a fully-associative victim buffer with a small block size, a fully-associative spatial buffer with a large block size, and a dynamic fetching unit. This new NAND-type flash memory package can achieve dramatically high performance and low power consumption comparing with any conventional NAND-type flash memory. Our results show that the NAND flash memory package with a smart buffer cache can reduce the miss ratio by around 70% and the average memory access time by around 67%, over the conventional NAND flash memory configuration. Also, the average miss ratio and average memory access time of the package module with smart buffer for a given buffer space (e.g., 3KB) can achieve better performance than package modules with a conventional direct-mapped buffer with eight times(e.g., 32KB) as much space and a fully-associative configuration with twice as much space(e.g., 8KB)

• Journal of Industrial Convergence
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• v.17 no.4
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• pp.9-14
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• 2019

This paper presents several problems that can occur in the development of the ultra-compact LED package of less than 1.0mm and introduces the solution to them. In the existing mold structure, since the upper and lower core parts are integrated, various errors have occurred due to the roughness of EDM in the small model, which is a limiting factor in further reducing the mold size. As a countermeasure, the prefabricated model was presented in an earlier study to overcome the obstacles to the development of a ultra-compact LED package. In this paper, several problems have been found during the fabrication of prototypes as a starting work to produce the results for the presented model. The types are suggested and the solutions are discussed. And by changing the existing 2-row structure to 3-row structure in the same size lead frame, the aspect of efficient production is considered. The experimental procedure verifies the proposed solution and conducts a test to produce a prototype to confirm that a good product can be produced.

• Journal of the Korea Society of Computer and Information
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• v.13 no.6
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• pp.279-286
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• 2008

The IT industry plays the engine role in Korean economy which reaches up to 17% of Korean GDP. However the current global economic depression which stems mainly from the US has caused insufficient demand in IT industry. The decreased demand leads to a drug in the market, to fierce price competitions and increasing fear on the world IT market depression. Considering the facts, there are strong demands for the diversification of the products of exports and the countries Korea exports to. These need differentiated strategies which can be summarized in various IT package-type overseas expansion model including the consideration in strategic items, countries, connecting large and small-medium size companies or businesses and related industries. The importance of IT industry in Korean economy will grow constantly and the IT package-type overseas expansion models will preside the movements.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1137-1142
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• 1998

Modified atmosphere packagings were designed by combining the respiration characteristics of the enoki mushroom at 10oC and the measured film permeabilities to O2 and CO2 gases to attain the beneficial package atmosphere were fabricated and tested during storage. The packages of 100g size with 30 m low density polyethylene and cast polypropylene showed the good agreement between estimated and experimental package atmospheres. However, polyvinylchloride stretch wrap packs showed the gas composition close to the air, which was due to leaking of stretch wrapping. The CPP package attaining O2 below 1% and CO2 concentration of 15~20% gave the best retention of quality and thus the longest shelf life among the tried packages, and it was superior to the others in the Hunter L value, stipe elongation and sensory qualties.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.4
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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.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.11
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• pp.1064-1073
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• 2013

In this paper, a compact 370 W high efficiency GaN(Gallium Nitride) HEMT(High Electron Mobility Transistor) power amplifier(PA) using internal harmonic manipulation circuits is presented for cellular and L-band. We employed a new circuit topology for simultaneous high efficiency matching at both fundamental and 2nd harmonic frequency. In order to minimize package size, new 41.8 mm GaN HEMT and two MOS(Metal Oxide Semiconductor) capacitors are internally matched and combined package size $10.16{\times}10.16{\times}1.5Tmm^3$ through package material changes and wire bonded in a new package to improve thermal resistance. When drain biased at 48 V, the developed GaN HEMT power amplifier has achieved over 80 % Drain Efficiency(DE) from 770~870 MHz and 75 % DE at 1,805~1,880 MHz with 370 W peak output power(Psat.). This is the state-of-the-art efficiency and output power of GaN HEMT power amplifier at cellular and L-band to the best of our knowledge.