• Journal of Forest and Environmental Science
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• 제14권1호
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• pp.89-100
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• 1998

본 연구는 제지 원료의 효율적 이용 및 기능의 최적화를 위한 수단으로 사용되고 있는 다층구조화에 따른 종이의 내부응력 및 물성의 변화를 조사하기 위하여 수행되었다. 또한 최근 사용량이 급증되고 있는 재생섬유를 다층구조에 도입할 경우 수반되는 종이의 물성 변화도 조사되었다. 펄프의 고해처리는 단층지의 내부응력을 증가시켜준 반면 충전제의 사용은 내부응력을 감소시켰다. 종이의 다층구조화는 인열지수를 제외한 대부분의 종이물성과 내부응력을 감소시켰으며, 이러한 변화는 사용된 펄프의 종류, 고해수준, 원료의 배합 방법에 따라 다양하게 나타났다. 충전시에는 충전제를 외층 또는 내층에 사용함으로써 단층지보다 우수한 내부응력 및 종이물성을 얻을 수 있었다. 재생섬유를 사용할 때는 다층구조화를 통하여 투기도와 빳빳이의 개선이 가능하였으나, 파열지수가 감소되었다.

• 한국도로학회논문집
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• 제6권4호
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• pp.55-63
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• 2004

효율적인 포장의 관리를 위해서 포장상태를 객관적으로 평가하는 포장평가지수의 사용은 필수적이다. 현재 사용되고 있는 PSI, MCI, UPCI는 사용자나 관리자의 입장만을 각각 고려하여 종합적인 포장평가지수의 역할을 못하고 있는 실정이다. 따라서 본 논문에서는 기존 평가지수들의 문제점을 파악하고 이를 개선한 새로운 포장평가지수를 개발하였다. 또한 개발된 평가지수로 실제 포장자료를 이용하여 포장재료의 성질에 따른 지수의 민감도 분석을 실시하였다. 표층두께, 아스팔트점도, 아스팔트함량의 순서로 포장평가지수에 영향을 주었다.

• 통합자연과학논문집
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• 제8권1호
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• pp.60-66
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• 2015

The physical and optical properties of polymers with 2-fluoroaniline and 4-fluoroaniline added, which can be used for hydrophilic ophthalmic lenses, were investigated in this study. The UV-blocking properties of 2- and 4-fluoroaniline were also investigated by measuring their UV transmissibility. 2- and 4-Fluoroaniline were used as additives for the basic combination of HEMA, 5% AA, and 1% MMA, and the materials were copolymerized with EGDMA as the cross-linking agent and AIBN as the initiator. The refractive index, water content, optical transmittance, tensile strength, and contact angle were measured to evaluate the physical properties of the produced hydrogel lens. The measured physical properties of the hydrogel contact lens produced with the copolymerized polymer showed a refractive index of 1.425-1.436; a water content of 36.95-44.65%; a visual light transmittance of 66.0-81.0%; a tensile strength of 0.138-0.281 kgf; and a contact angle of $55.02-57.87^{\circ}$. The UV transmissibility was significantly reduced, which indicates that 2-fluoroaniline and 4-fluoroaniline have UV-blocking properties. This study showed that 2- and 4-fluoroaniline are expected to be used as UV-blocking materials in hydrogel ophthalmic lenses whose physical properties, such as their refractive index and water content, do not change.

• 한국관광식음료학회지:관광식음료경영연구
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• 제13권1호
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• pp.55-68
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• 2002

Flow properties of doenjang samples at various total solid contents (30, 32, 34, 36, 38, 40%) were evaluated in this study. Flow properties of doenjang samples was determined by using Haake concentric cylinderical viscometer and Instron testing machine with capillary extrusion viscometer, and consistency index(K), and flow behavior index(n) was also determined from power models, and yield stress was derived form Casson models and vanes methods. Doenjang samples showed shear-thinning (pseudoplastic) fluid with small magnitude of flow behavior index(n) (n=0.30-0.55). Casson yield stress was from 2.11 to 64.02(Pa). Vane yield stress was more effective than casson yield stress in property of reactivation. Apparent viscosity was decreased with the increase in temperature and activation energy was in the range of 6.58 to 10.70 kJ/mole. From the capillary extrusion method, K and n was increased with the increase in solid content with good correlation with. The result revealed that capillary extrusion method is useful for measuring the flow properties of doenjang.

• Journal of Biosystems Engineering
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• 제32권4호
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• pp.207-214
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• 2007

Based on the profiles of cone index with depth, physical properties of hardpan in selected rice fields were measured and analyzed in the study. An error correction algorithm removing a random measurement error from raw CI profile data was introduced in the study. The properties of hardpan included the shape, the thickness and the rice root growing layer. The analysis of physical properties of hardpan in the rice fields showed that the type of hardpan could be classified into 6 categories. The thickness of hardpan ranged from 6 cm up to 41 cm and the average hardness of hardpan was analyzed to be from 1.1 MPa through 3.2 MPa in Cone index.

• Bulletin of the Korean Chemical Society
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• 제15권2호
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• pp.106-112
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• 1994

Six physical properties (molecular weight, heat capacity, side chain weight, side chain volume, standard entropy and partial molar volume) of amino acids, peptides and their derivatives were examined by molecular modeling techniques. The molecular connectivity index, Wiener distance index and ad hoc descriptor are employed as structural parameters to encode information about branching, size, cyclization, unsaturation, heteroatom content and polarizability. This paper examines the correlation of the molecular modeling techique's parameters and the physicochemical properties of amino acids and their derivatives. As a result, calculated values were in agreement with experimental data in the above six physical properties of amino acids, peptides and their derivatives and the molecular connectivity index was superior to the other indices in fitting the calculated data.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.962-965
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• 1999

We designed and fabricated a travelingwave CPW(coplanar waveguide) electrode for LiNbO$_3$ optical modulator. To Investigate the variation of microwave refractive index of these electrodes, we prepared the CPW electrode samples as a function of electrode thickness and measured the TDR and S-parameter. From this results, we could know the electrode conditions of index matching to 2.20 for 1550nm optical wave index for applying LiNbO$_3$ optical modulator and described. Also, we discussed the some properties of CPW electrode for applying LiNbO$_3$ optical modulator.

• 한국가스학회지
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• 제16권6호
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• pp.115-122
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• 2012

LNG저장탱크의 보냉제로 사용되는 폴리우레탄 폼의 NCO index에 대한 영향을 알아보기 위해 대체발포제인 HFC-365mfc를 사용하여 NCO index와 촉매를 변화시키면서 폴리우레탄 폼을 합성하였다. 폴리우레탄 폼의 물성변화를 고찰하기 위해 만능시험기, 시차주사열량계, 주사전자현미경, 적외선 분광기를 이용하였다. 촉매의 종류를 PC-8과 33LV, TMR-2로 변화시키고 양을 변화시킨 결과 촉매의 종류에 따라 압축강도의 차이가 발생하였으나 밀도에는 영향을 미치지 않음을 확인하였다. 또한 촉매의 첨가량이 증가할수록 압축강도도 증가하는 경향을 나타내었다. 겔화촉매인 PC-8과 33LV를 사용한 폼을 노화시킨 결과 NCO index가 증가하면 유리전이온도와 압축강도가 증가하였으나 삼량화 촉매인(TMR-2)를 사용한 폼을 노화시킨 결과 노화전후의 물성차이가 발생하지 않았으며 이는 초기 반응시 삼량화 여부에 기인함을 FT-IR을 사용하여 규명하였다.

• 펄프종이기술
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• 제41권2호
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• pp.7-12
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• 2009

The effects of refining either SwBKP or HwBKP, and both of SwBKP and HwBKP on the physical properties of paper were investigated in order to elucidate if the non-conventional refining and blending method can be used for the optimizing the paper properties. The blending ratio of SwBKP and HwBKP was 15:85. The highest bulk was obtained with the refining of SwBKP only. Any differences of opacity were not observed in unfilled paper, while the highest opacity of PCC filled paper was obtained at same bulk when the only HwBKP was refined. However burst index and tensile index did not showed any differences in the relationship with bulk. Therefore this result can be applied to improve the opacity of paper without sacrificing of strength properties.

• 한국토양비료학회지
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• 제42권3호
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• pp.160-166
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• 2009

We estimated site productivity for unstocked land based on the relationship between site index (i.e., average height of dominant trees at fixed age) and soil physico-chemical properties of Pinus densiflora stands. Site index relates to a direct method of determining a tree's response to a specific environment such as forest soil and climate conditions. We selected 78 sites in 22 P. densiflora stands of central temperate forest zone, and sampled soils for physicochemical analyzing. And 13 properties of soils were statistically treated by stepwise regression. In the degree of contribution of the variables to site index, the highly effective variables in A horizon were OM, clay content, sand content, available $P_2O_5$, and Exch. $Ca^{{+}{+}}$ inorder, and in B horizon T.N., O.M., Soil pH, cation exchange capacity(C.E.C.), and sand content in order. In both A and B horizon of the soil for P. densiflora stands, the variables commonly contributed to the site index were sand content and OM. These results may be useful to provide not only important criteria for establishment of Pinus densiflora stand sespecially in unstocked land but also aguidance for reforestation.