• Journal of the Korean Wood Science and Technology
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• v.22 no.4
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• pp.19-25
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• 1994

The purpose of this study was to determine the technical feasibility of making 3-dimensional thin hardboard panels for overlay substitutes of low grade particleboard and plywood panels. Experimental studies were directed at assembling bench-top apparatus, learning the characteristics of different types of lignocellulosic waste papers, for making thin hardboard with several combinations of them with and without resin addition. The raw materials used are waste corrugated cartons, cereal boxes, and old magazines which contain substantial amount of lignin in it. The experimental results showed that satisfactory thin(0.21~0.16cm) hardboard could be made from the residential mixed waste papers that have selected properties comparable to commercial 0.32cm hardboard. The significant mixing ratio effect of the waste papers was present on the thickness swelling, water absorption, linear expansion, and modulus of elasticity including Taber abrasion tests of the thin hardboard made. The mixing ratio of waste papers and resin in the thin hardboard prominently affected the specific gravity of it, which led to affect modulus of elasticity and those physical properties sensitively. And it was shown that the hardboard containing those physical properties can be used for overlay substitutes of low grade plywood and particleboard panels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.5
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• pp.858-865
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• 2006

A certificate that is issued by the certification authority can be revoked within the period of validity by various reasons such as the loss of private key, disqualification or the change in key. Therefore, the certificate status verification must precede prior to use Currently, the CRL or the OCSP methods are used in most cases. But the CRL system can't guarantee the present status of the certificate, and the OCSP generates heavy network traffic by checking or requesting certificate status in real-time using high-capacity messages. In this paper, we propose a system that requests the certificate verification by creating VDN for user identity information. Through this system, the certification authority will be able to guarantee the certificate's status in real-time, and solve the problem of the sewer and network overload by verifying and finding user identity information from VDN, Based on the results, we propose a real-time certificate status verification system which can improve the speed of the verification. We confirmed the improvement in speed by testing and comparing it with the existing methods.

• 월간 기계설비
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• no.12 s.221
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• pp.39-43
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• 2008

기획재정부는 최근 중소건설업계의 경영환경 악화에 따른 경영애로를 완화하고 불합리한 제도를 개선하기 위해 국가 계약관련 회계예규를 개정하고 지난 11월 1일부터 시행에 들어갔다. 개정된 회계예규는 원자재 가격급등시 계약금액의 10% 범위 내에서 선금을 추가지급하게 해 이 돈을 자재확보 용도로 우선 사용할 수 있게 했다. 또한 원자재 가격급등으로 인한 계약금액의 조정을 원활하게 하기 위한 기준도 신설했다. 물가변동이 5% 이상물품구매는 10% 이상 상승하는 등 원자재 가격급등시에는 계약일로부터 90일 이내라도 계약금액을 조정할 수 있도록 했다. 현행 원자재 가격급등으로 인한 계약금액 조정은 일반적으로 계약일로부터 90일이 경과하고 물가변동이 3% 증감한 경우 기능하게 돼 있다. 대한설비건설협회는 자재가 급등으로 설비건설업계기 어려움에 처하자 자재가격 급등에 따른 계약금액을 변동시켜 줄 수 있도록 관련법 개정을 요청한 바 있다. 이에 따라 기획재정부기 회계예규 개정에 대한설비건설협회의 의견을 수용, 반영한 것이다. 개정된 회계예규는 또 종합건설업과 전문건설업간 겸업제한 폐지 및 실적인정에 따른 영업기간 인성 규정을 마련, 새로 등록한 업종으로 공공공사 입찰에 참여할 수 있게 해 종합 전문건설업간 상호 진출에 기여토록 했다. 지역중소업체 입찰참여가 쉽도록 1천억원 이상 대형공사(턴키 등) 에서 공동수급체 구성원수를 10 인 이내로 확대하기로 했다. 또한 300억원 미만의 적격심사낙찰제 대상공사 입찰시에 기업의 경영상태 평가는 원칙적으로 1년 이내 기업신용평가등급으로 평가하기로 했다. 이밖에 공동수급체 대표자 또는 수급인이 선금을 수령하고도 정당한 이유없이 공동수급체 구성원 또는 하수급인에게 배분하지 않는 사례를 막기 위해 계약담당공무원이 선금 배분여부를 확인하도록 하고 선금 사용 용도도 명시적으로 규정했다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.4A
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• pp.304-311
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• 2005

OCSP has specific characters which can suspend, close, and correct in real time. But, as more clients use the OCSP server verification, more updated information is needed, which can lead to jamming in the OCSP server. To apply this technique of Distributed OCSP server so as to reduce the certificate verification OCSP from jamming. Also, the Distributed OCSP server will solve the problems of the intensive central structure. Simulation results show that the average reply time of certificate verification request and server load are reduced in the case using distributed OCSP. In addition to this advantage, resource distribution and fault tolerance are acquired because of multiple OCSP.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.4
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• pp.304-310
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• 2018

The aim of the research is to provide possibility of quality controlling by rheological properties for lightweight foamed concrete. The lightweight foamed concrete achieves its low density by containing air bubbles (foam) produced during the mixing process. Therefore, containing foamed volume during setting period is critical for the securing the performance as an insulating material. In this research, regarding foam collapse during the setting period, rheolgocial properties of fresh state lightweight foamed concrete were assessed to get its relationship with volume stability, or foam stability. For the experiment regarding foaming factors including mixing time, mix design of contents for materials, rheological properties of fresh state lightweight foamed concrete were tested with its density and settling depth. Based on the settling depth with various factors, relationship with rheological properties was analyzed, and especially, close relationship of plastic viscosity and settling depth was found. Therefore, from the results of this research, it is considered to contribute on suggesting a new approach of quality controlling for lightweight foamed concrete using rheological test method.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.80-88
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• 2014

This study was carried out to understand the effect of sowing date on growth characteristics, flower duration of a total of 6 domestic rapeseed cultivars, "Sunmang", "Tammiyuchae", "Tamlayuchae", "Naehanyuchae", "Yongsanyuchae" and "Hallayuchae" with different sowing dates (25 Sept., 5 Oct., 15 Oct., 25 Oct., 5 Nov.) in Muan, Jeollanamdo, Republic of Korea. The results obtained were summarized as the follows: The number of seedling stand after overwintering was decreased in all 6 cultivars. It changed little until 5 Oct., and then showed continuously largely decrease as the sowing date being delayed. As the sowing date was being delayed, plant height was decreased while Silique length and thousand seed weight were increased. Seed yield in all 6 cultivars decreased almost linearly with late sowing date. In correlation analysis between the delaying sowing date and growth characteristics, it was inversely correlated with plant height ($r=-0.769^{**}$), No. of branches/plant ($r=-0.760^{**}$), No. of siliqua/panicle ($r=-0.631^{**}$) and seed yield ($r=-0.946^{**}$), while showed a positive correlation with silique length (r=0.635), seed diameter ($r=0.629^{**}$) and thousand grain weight ($r=0.422^*$). No. of seeds/silique and seed set percentage were not significantly correlated with the delaying sowing date. The flower duration was long in order of Sunmang, Tammiyuchae, Yongsanyuchae, Naehanyuchae, Hallayuchae and Tamlayuchae. Varietal variation of flowering date was larger with early sowing date than with delaying sowing date. The range of flower duration across all cultivars was from 1 day of Tamlayuchae to 14 days of Sunmang according to the sowing date, and the end flowering date was able to be extended from 2 to 9 days, compared to normal date of end flowering.

• Korean Journal of Heritage: History & Science
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• v.37
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• pp.445-469
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• 2004

The Avatamsaka Sutra copied in ink on the white paper of Shilla Period is the oldest manuscript in korea. This Avatamsaka Sutra is volume 1-10 and 44-50 of the 80 volume's transcription. According to the postscript, written with 528 letters at the end of the volume 10 and 50, this sutra is made during A.D. 754-755, for six months by the order Master Yon-gi(綠起 法師) who founded Hwaumsa Temple(華嚴寺.) It explains the procedure of the ritual and production method of the sutra-copying, and also shows the 19 participants with their name, address, official title, and etc. When the sutra was founded, volume 1-10 were so congealed that we could not open the volumes. And volume 44-50 was prohibited to take photograph for preservation. According to the recent examination, it proved that this sutra is the treasure for the study of the characters made by Empress Wu Zetian(則天武后.) The characters made by Empress Wu Zetian(A.D. 625-705) are new shape of chinese characters which is different from the traditional characters. After the demise of the Queen, the characters were not used any more officially, but privately some people used the characters for personal tastes and interest. The characters in the sutra includes 512 characters of 13 kinds of Empress We Zetians'. Compared to the Tun-huang version of the sutra, this is far better treasure for the study of Empress We Zetians' characters in terms of the number of the character and the their use of frequency. The Avatamsaka Sutra of Shoso-in(正倉院) in japan copied in A.D. 768 does not use the Empress We Zetians' characters. In this respect, this Shilla Avatamsaka-Sutra is a unique one preserves the original forms of Chinese translation at that time.