목재와 목질판상의 Dowel-Joint 판강접합 특성에 관한 비교분석

박희준,이필우(Hee Jun Park),Phil Woo Lee 한국가구학회 1990 한국가구학회지 Vol.1 No.1

The dewel joint is one of the most widely used joint types in modern woodworking, especially in wooden furniture manufacturing.<br/> L-type specimens of two solid woods(Antiaris, Sepetir) and three wood based materials (Plywood, Particleboard, and Medium Density Fiberboard), 15mm thick, 100mm wide, and 150mm long in size, were constructed with 1, 2, 3 and 4 dowels of 6, 8, and 10mm diameter by polyvinyl acetate resin adhesive in this study. Stiffness coefficient and strength of the L-type specimens were determined by the aid of universal testing machine.<br/> The stiffness coefficients of the specimens constructed with one dowel was in the 10^-3 level, indicative of flexible joints but those with 2, 3, 4 dowels were in the 10^-4 level, indicative of relatively stable joint. The 8mm dowel was superior to 6 and 10mm dowels in bending strength, and the bending strength increased with the increase of dowel number from 1 to 4, however, the increasing rate of bending strength from 1 to 2 dowels was higher than from 3 to 4 dowels.<br/> The most superior joints strength was obtained in constructions with 4 dowels of 8mm diameter for wood based materials (Plywood, particleboard and Medium Density Fiberboard) and with 4 dowels of 10mm diameter for solid wood(Antiaris and Sepetir), respectively.

< 구두-E-09 > 목재-마그네슘 적층복합재(WM Board)의 물리적 및 기계적 성질

박희준 ( Hee-jun Park ),조석운 ( Seok-un Jo ),강춘원 ( Chun-won Kang ) 한국목재공학회 2019 한국목재공학회 학술발표논문집 Vol.2019 No.1

실내 마감용 건축재료의 안전과 환경에 대한 중요성이 어느 때 보다도 강조되고 있는 상황에서 기존에 널리 적용되고 있는 무기질계(석고, 질석, 마그네슘, 대리석, 타일 등), 합성수지계 그리고 금속제 건축마감재를 대체할 수 있는 목질계 친환경 실내마감재를 개발하고자 수행하였다. 본 연구에서는 무기질계 건축마감재의 대표적인 단점, 단열성, 내충격성, 휨강도, 흡음성, 오염물질방출, 내구성 등을 개선하고 목재의 난연성과 경제성 등을 개선시킨 흡음성 벽·천장용 목재-무기질 적층복합재(WM Board)를 개발하고자 수행하였다. 본 연구에서 개발한 WM Board는 두께 3mm 마그네슘보드 양면에 두께 1.6mm 라디에타파인 단판(Pinus radiata Veneer)을 EVA(Ethylene Vinyl Acetate Copolymers)수지를 사용하여 적층·접착하여 제조하였다. 제조된 보드는 비중, 함수율, 휨강도, 낙구충격시험, 열저항, 흡음성, 방염성, 난연성 및 준불연성, 실내오염물질 방출량 등을 시험평가하고, 공인시험성적서 획득, 시제품제조, 시공성 평가 등을 거쳐 산업화를 위한 표준규격서 개발, 생산시스템 구축 등을 진행하였다. 개발제품의 성능평가 결과 한국, 일본, 유럽연합, 중국, 미국 등 세계 각 국의 화재안전기준에 적합하고 관련 법령 및 기준에서 제시하고 있는 실내소음환경 개선(흡음성), 에너지 절감(단열성), 내구성, 실내공기질 개선, 경제성 등에 기여할 수 있어 기존의 무기질계, 금속계, 합성수지계 제품을 대체할 수 있는 새로운 목질계 복합재로 'WM Board'의 신상품화 및 신산업화가 가능할 것으로 기대된다.

Adler 개인심리학에 근거한 청소년의 학습동기향상 프로그램 개발 및 효과검증

박희준 ( Park Hee Jun ),김원중 ( Kim Won Jung ) 경남대학교 교육문제연구소 2019 敎育理論과 實踐 Vol.28 No.-

The purpose of the study is to develop learning motivation enhancing program and to verify the effects on self-determination motivation, academic self efficacy, and social interest based on the Adler’s individual psychology. The subjects of this study were 30 third grade students. For statistical methods, repeated measurement analysis and multiple comparison analysis were used. The results of the study are as follows. First, the result of the development of the learning motivation enhancing program based on the Adler’s individual psychology improved and maintained self-determinate motivation. Second, the result of the development of the learning motivation enhancing program based on the Adler’s individual psychology improved and maintained academic self-efficacy. Third, the result of the development of the learning motivation enhancing program based on the Adler’s individual psychology improved and maintained social interest. Finally, discussion and suggestion of the learning motivation enhancing program based on the results of the study were proposed.

금융소득 종합과세에 관한 연구 -기준금액 인하의 영향을 중심으로-

박희준 ( Hee Jun Park ),정래용 ( Rae Yong Jung ) 홍익대학교 법학연구소 2014 홍익법학 Vol.15 No.3

In this study, there is an examination on market situations and problems in accordancewith the changes of standard amount of general taxation and discussion about itsimprovement plan. First, when standard amount of general taxation is lowered from 40 million to 20million won, the fund might be concealed abroad due to an evasion of general taxation. Thus, with reference to global situation, standard amount is reduced gradually and it isabolished. At last, it is able to raise the transparency of financial market. Second, as for saving insurance, It is excessively large amount in non-taxableconditions so that the conditions for limitation and term tighten up. And during theinsurance payment term, reporting system about the assessable payment or the conditionfor insurance payment is made every year. then the insurance also is in the samecategory as other financial items and manages tax resources. Third, With the reinforcement on penal provision of borrowed account possession, itimposes on the minimum of penalty in case of voluntary report within certain periodof time. Therefore, an incorporation of fund concealing is led into the financial market system in this country. Fourth, as a judgment on income in health insurance fee system is based on generalincome tax which is taken over from National Tax Administration, Therefore classifiedtaxation income such as a transfer income and a retirement income etc., non-taxableincome, and taxation income should be included in standard of assessment of healthinsurance fee.Then, it will provide the fair equal split of insurance on classification of income.

송신 MIMO-OFDM 시스템의 V-BLAST 선행처리 기법

박희준(Hee-Jun Park),안진영(Jin-Young An),김상준(Sangchoon Kim) 한국정보기술학회 2010 한국정보기술학회논문지 Vol.8 No.3

In this paper, we consider a precoding scheme that reduces the receiver’s complexity in MIMO-OFDM(Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing) systems. It adopts V-BLAST(Vertical-Bell Laboratories Layered Space-Time) technique to transmit the signals and employs ZF(Zero-Forcing), ZF-QRD(QR Decomposition), MMSE(Minimum Mean Squared Error) for V-BLAST receiver. There are two ways for precoding the V-BLAST receiver in the transmit MIMO-OFDM system. An AT(Antenna Transmit) scheme organizes the V-BLAST precoder just before transmit antennas. A MT(MIMO encoder Transmit) scheme consists of the V-BLAST precoder right after MIMO encoder. We compare the BER performance between the precoding V-BLAST system and the postcoding V-BLAST system in MIMO-OFDM. The results show that the transmit MIMO-OFDM system can simplify the receiver structure without the degradation of the BER performance compared to the receive MIMO-OFDM system.

A Numerical Study on Strut-Placed Supersonic Flow in Annulus Flowfield

박희준(Hee Jun Park),주원구(Won Goo Joo) 한국전산유체공학회 2002 한국전산유체공학회 학술대회논문집 Vol.2002 No.-

In this numerical approach, strut~placed supersonic annular flow is examined. The geometrical variations of strut cause strong influence on flowfield structures. The geometrical variations are as follows ; swept effect, attack angle effect, variation of leading edge shape. These changed features such as velocity structure, pressure structure, shock-boundary layer interaction are compared and analyzed according to each geometrical configuration.

전동차의 실내소음저감 설계 우선 순위 분석

박희준(Park Hee Jun),손병구(Son Byoung Gu),김근필(Kim Geun Pil) 한국소음진동공학회 2020 한국소음진동공학회 학술대회논문집 Vol.2020 No.11

재질개량 침엽수 간벌 소경재를 이용한 목제욕조 제조기술에 관한 연구

박희준(Hee Jun Park),이남호(Nam Ho Lee) 한국가구학회 1997 한국가구학회지 Vol.8 No.1

This study was carried out to develop the manufacturing techniques of new wooden bathtub and wooden tile to utilize thinned softwoods for bathroom.<br/> The manufacturing process of wooden bathtub was composed of 8 stages; (1) sawing and drying, (2) lamina cutting, (3) laminated assembly, (4) joint processing, (5) treated with preservatives, (6) bathtub assembly, (7) treated with urethan -resin, (8) treated with fluoro-resin.<br/> Isocyanate adhesives(KR-120) showed good bonding propeties in water proofing, warm-water proofing, and boil proofing test. <br/> Wooden bathtubs treated with urethan-resin and fluoro-resin were free from any defects by KS F 2826. Especially, wooden bathtub treated with Huoro-resin showed excellent properties in hot-water resistance, boil proofing, accelerated weathering than those of urethan resin. But in abrasion resistance and washing resistance, treatments with urethan-resin were more superior than those of Huoro-resin.<br/> So, it is considered to be desired that urethan-resin was applied at the first and second coat and Huoro-resin was applied the final coat.<br/> The manufacturing cost of a wooden bathtub made with thinned softwood was counted about 184,057won and this cost comes under one tenth of Japanese wooden bathtub made with Chamaecyparis obtusa.<br/>

이태리 포플라와 낙엽송 세이빙으로 제조한 보드의 휨강도와 박리강도

박희준(Hee Jun Park),윤형운(Hyoung Un Yoon),이필우(Phil Woo Lee) 한국가구학회 1996 한국가구학회지 Vol.7 No.1

Non-oriented shaving boards were made with Italian popular(Populus canadensis Moench), Japanese larch(Larix letolepis Gorden) planer shavings and commercal coarse chips and UF resin, PF resin and MDI adhesives.<br/> Physical properties and manufacturing cost were ε valuated. Physical properties evaluated were static bending and internal bond strength.<br/> Boards made of lower density species were superior static bending properties to particleboard made of coarse chips and commercial particleboard. Especially, boards of shavings from low density species shower superior mechanical properties according to increasing the compression ratio.<br/> As a result, the shaving board, though its specific gravity is lowered by 0.05 to 0.1, is expected<br/> not to be less than commercial particleboard in physical properties.<br/>

MIMO-OFDM 시스템에서 V-BLAST 수신기의 성능

박희준(Hee-jun Park),안진영(Jin-young An),김상준(Sang-choon Kim) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.10

본 논문은 MIMO(Multiple Input Multiple Output) OFDM(Orthogonal Frequency Division Multiplexing)시스템에서 V-BLAST(Vertical-Bell Laboratories Layered Space Time) 수신기에 대하여 성능을 비교하고 평가한다. 신호는 각각의 송신 안테나에서 독립적으로 전송되며 QPSK(Quadrature Phase Shift Keying) 방식을 이용하여 변조 되고, 송 · 수신단에 각각 2개의 안테나와 각각 4개의 안테나를 사용한다. V-BLAST 수신기로 ZF(zero-Forcing), MMSE(Minimum Mean Squared Error), ZF-OSIC(Zero Forcing - Ordered Successive Interference Cancellation), MMSE-OSIC(Minimum Mean Squared Error - Ordered Successive Interference Cancellation)를 사용한다. 모의실험 결과에서 MMSE 방식이 ZF 방식 보다 좋은 BER(Bit Error Rate)을 보이고, ZF-OSIC 방식은 ZF 방식과 MMSE 방식 보다 더 좋은 BER을 가지는 것을 확인 할 수 있으며, MMSE-OSIC 방식은 사용된 방식 중 가장 좋은 성능을 보인다.