• Asian-Australasian Journal of Animal Sciences
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• 제12권8호
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• pp.1292-1297
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• 1999

A preference test on feed and nutrient intakes were conducted on four male ($1.25{\pm}0.08kg$) and four female ($1.21{\pm}0.15kg$) lesser mouse deer (Tragulus javanicus) in captivity. Each animal was kept in individual cages placed in a well-ventilated animal house. The experiment was conducted in two weeks, where the first week was for adaptation to the feeds and the second week for measurements of nutrient intake, nutrient digestibility and nitrogen balance. The feeds offered were kangkong (Ipomoea aquatica), long bean (Vigna sinensis) and french bean (Phaseolus vulgaris) as roughages and proteinaceous feeds; sweet potato (Ipomoea batatas) and carrot (Daucus carota) as carbohydrate-rich feeds; and commercial rabbit pellet (0.3 cm diameter and 0.5 cm long) as a complete feed. The dry matter (DM) content of each feed in the order mentioned above was 7.1, 6.1, 3.9, 18.5, 6.2 and 87.6%, respectively. Long bean had the highest protein (CP) content (29.7%), while sweet potato had the lowest (6.2%). The CP contents of other feeds were within the range of 14.2 - 25.1%. Among the feeds, carrot had the lowest energy content (3.83 kcal/g) and long bean the highest (4.67 kcal/g). When fresh weight of the feed was considered, the male mouse deer consumed sweet potato the most ($86.3{\pm}12.90g/d$), but the female had a high preference for carrot ($79.2{\pm}9.76g/d$). The other feeds were consumed in lesser amounts. However, in terms of DM of the feed, the amount of commercial pellet consumed was the highest for both male ($45.0{\pm}5.10%$) and female ($44.7{\pm}7.38%$) mouse deer, followed by sweet potato ($33.1{\pm}4.43%$ and $22.4{\pm}7.73%$ for male and female, respectively). Significant (p<0.05) differences in DM, organic matter (OM) and gross energy (GE) intakes were observed between male and female mouse deer. The male consumed higher amount of DM, OM and GE than the female. The total DM intake was $40.7{\pm}2.24g/d/kg$ $W^{0.75}$ for male and $35.9{\pm}1.72g/d/kg$ $W^{0.75}$ for female mouse deer. Percentage digestibilities of DM, OM, CP and GE were within 72.7~80.8% and were not significantly different between male and female mouse deer. However, male mouse deer had significantly (p<0.05) higher digestible DM, OM and GE intakes than the female. Both male and female mouse deer were in positive nitrogen balance (0.6 g N/d/kg $W^{0.75}$). The male mouse deer gained $7.6{\pm}3.45g/d$, while the female gained $4.3{\pm}2.40g/d$.

• 마이크로전자및패키징학회지
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• 제27권1호
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• pp.1-7
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• 2020

The backside metallization process is typically used to attach a chip to a lead frame for semiconductor packaging because it has excellent bond-line and good electrical and thermal conduction. In particular, the backside metal with the Ag/Sn/Ag sandwich structure has a low-temperature bonding process and high remelting temperature because the interfacial structure composed of intermetallic compounds with higher melting temperatures than pure metal layers after die attach process. Here, we introduce a die attach process with the Ag/Sn/Ag sandwich structure to apply commercial semiconductor packages. After the die attachment, we investigated the evolution of the interfacial structures and evaluated the shear strength of the Ag/Sn/Ag sandwich structure and compared to those of a commercial backside metal (Au-12Ge).

• Wind and Structures
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• 제28권3호
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• pp.171-180
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• 2019

This paper presents a restart iterative approach for time-domain flutter analysis of long-span bridges using the commercial FE package ANSYS. This approach utilizes the recursive formats of impulse-response-function expressions for bridge's aeroelastic forces. Nonlinear dynamic equilibrium equations are iteratively solved by using the restart technique in ANSYS, which enable the equilibrium state of system to get back to last moment absolutely during iterations. The condition for the onset of flutter instability becomes that, at a certain wind velocity, the amplitude of vibration is invariant with time. A long-span suspension bridge was taken as a numerical example to verify the applicability and accuracy of the proposed method by comparing calculated results with wind tunnel tests. The proposed method enables the bridge designers and engineering practitioners to carry out time-domain flutter analysis of bridges in commercial FE package ANSYS.

• 한국재료학회지
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• 제33권10호
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• pp.414-421
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• 2023

Infrared radiation (IR) refers to the region of the electromagnetic radiation spectrum where wavelengths range from about 700 nm to 1 mm. Any object with a temperature above absolute zero (0 K) radiates in the infrared region, and a material that transmits radiant energy in the range of 0.74 to 1.4 um is referred to as a near-infrared optical material. Germanate-based glass is attracting attention as a glass material for infrared optical lenses because of its simple manufacturing process. With the recent development of the glass molding press (GMP) process, thermal imaging cameras using oxide-based infrared lenses can be easily mass-produced, expanding their uses. To improve the mechanical and optical properties of commercial materials consisting of ternary systems, germanate-based heavy metal oxide glasses were prepared using a melt-cooling method. The fabricated samples were evaluated for thermal, structural, and optical properties using DSC, XRD, and XRF, respectively. To derive a composition with high glass stability for lens applications, ZnO and Sb₂O₃ were substituted at 0, 1, 2, 3, and 4 mol%. The glass with 1 mol% added Sb₂O₃ was confirmed to have the optimal conditions, with an optical transmittance of 80 % or more, a glass transition temperature of 660 ℃, a refractive index of 1.810, and a Vickers hardness of 558. The possibility of its application as an alternative infrared lens material to existing commercial materials capable of GMP processing was confirmed.

• 한국환경농학회지
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• 제18권3호
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• pp.280-286
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• 1999

음식물 쓰레기 퇴비화를 위한 미생물제 첨가 효과를 검토하기 위해 시판 미생물제 중의 미생물 활성과 퇴비화시의 접종효과를 조사하였다. 14종의 시판 미생물제의 배양온도에 따른 세균수 측정한 결과 $30^{\circ}C$에서는 대조구로 사용한 완숙퇴비의 $91.0{\times}10^8\;CFU/g$ 보다 모두 적게 나타났으며 $50^{\circ}C$와 $60^{\circ}C$에서는 각각 5종과 6종의 미생물제가 완숙퇴비 보다 적게 조사되었다. 사상균의 경우 $30^{\circ}C$에서는 4종의 미생물제가 $10^5CFU/g$이상 존재하는 것으로 나타났으나 $50^{\circ}C$와 $60^{\circ}C$에서는 $10^3CFU/g$에서 검출되지 않았다. 방선균의 경우 $30^{\circ}C$와 $50^{\circ}C$에서 DE를 제외한 13종의 미생물제에서 $10^5CFU/g$ 이상으로 검출되었으나 $60^{\circ}C$에서는 전시료구에서 검출되지 않았다. 음식물 쓰레기에 미생물제를 접종하여 퇴비화 과정중의 $CO_2$ 가스 발생량을 실험실 조건에서 조사한 결과 VP>HU>B9>GE>CM>Contrl>Compost 순으로 조사되었으나 발생량의 차이는 거의 없는 것으로 나타났다. 한편 간이 음식물 쓰레기 퇴비화 장치에 선발한 미생물제를 접종한 후 퇴비화 실험을 수행한 결과 부숙온도 유기물 및, pH 변화에 영향이 거의 없었으며 중금속 양이온함량에서도 차이가 인정되지 않았다.

• Current Optics and Photonics
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• 제3권6호
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• pp.510-515
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• 2019

In this paper, we introduce a 1.3-㎛ 25-GHz waveguide-integrated vertical PIN type Ge-on-Si photodetector fabricated using a multi-project wafers service based on fringing field analysis in the depletion region. In general, 1.3-㎛ photodetectors fabricated using a commercial foundry service can achieve limited bandwidths because a significant amount of photo-generated carriers are located within a few microns from the input along the device length, and they are influenced by the fringing field, leading to a longer transit time. To estimate the response time, we calculate the fringing field in that region and the transit time using the drift velocity caused by the field. Finally, we compare the estimated value with the measured one. The photodetector fabricated has a bandwidth of 20.75 GHz at -1 V with an estimation error of <3 GHz and dark current and responsivity of 110 nA and 0.704 A/W, respectively.

• Journal of Radiation Protection and Research
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• 제34권2호
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• pp.83-86
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• 2009

The single crystal scintillator of bismuth germinate ($Bi_4Ge_3O_{12}$:BGO) was successfully grown by the conventional Czochraski technique. The characteristics of the grown BGO were evaluated and presented on the excitation, emission responses and energy spectra of the $\gamma$-rays from $^{241}Am$, $^{133}Ba$, $^{57}Co$, $^{22}Na$, $^{137}Cs$ and $^{54}Mn$ radio-isotopes. The energy resolution of grown BGO, $\Delta$E/E, was estimated to be 12.1% at 662 keV of $\gamma$-ray for $^{137}Cs$ nuclide. Compared to the commercial BGO crystal, we confirmed that the grown BGO has a good performance and is comparable to reference one.

• 한국전자파학회논문지
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• 제26권3호
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• pp.283-291
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• 2015

본 논문에서는 높은 Q 인자를 갖는 수동 회로의 정합 특성을 향상시키기 위한 비 포스터 정합의 핵심 요소인 부성 임피던스 변환기를 설계하여 구현하였다. 제안된 부성 임피던스 변환기는 Linvill의 트랜지스터 부성 임피던스 변환기 회로를 채택하여 구현하였다. 전력 이득 소자와 양성 피드백으로 구성된 부성 임피던스 변환기는 동작이 매우 불안정하여 발진 등으로 인해 제작 결과를 쉽게 예측하기 어렵기 때문에, 하이브리드 회로로 먼저 구현하여 가능성을 살펴본 뒤 집적회로로 설계하여 제작하였다. 상용 $0.18{\mu}m$ SiGe BiCMOS 공정을 사용하여 제작하였고, 목표로 하는 700~960 MHz 대역에서 리액턴스를 상쇄하여 비 포스터 정합이 이뤄짐을 확인할 수 있었다.

• 한국정보통신학회논문지
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• 제18권8호
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• pp.2023-2028
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• 2014

본 논문에서는 광민감 광섬유와 일반 단일모드 광섬유로 제작된 광섬유 브래그 격자 센서의 감마방사선 영향을 분석하였다. 제작된 광섬유 브래그 격자는 $Co^{60}$ 감마선원을 이용하여 300 Gy/min의 선량률로 총선량 17.8 kGy 감마선을 조사하였다. 실험결과를 통하여 수소로딩을 하지 않은 광민감 광섬유로 제작된 브래그 격자가 가장 낮은 약 18 pm의 브래그 파장 이동을 보였다. 또한 방사선 조사에 의한 브래그 파장변화는 광섬유 코어의 $GeO_2$ 함량보다는 수소로딩 공정에 훨씬 큰 영향을 받는다는 것을 확인하였다.

• 농업과학연구
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• 제46권3호
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• pp.569-577
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• 2019

The current experiment was conducted to compare nutrient utilization in the aged laying hens with different eggshell strengths or different intensities of brown eggshell color. Two metabolic trials with 96-week-old Hy-Line Brown laying hens were conducted. Twelve hens with a strong eggshell strength (SES) and 12 hens with a weak eggshell strength (WES) were selected and used in the first experiment, whereas 12 hens with dark brown eggshells (DBE) and 12 hens with light brown eggshells (LBE) were selected and used in the second experiment. All hens were fed a common commercial layer diet. Diets included chromic oxide as an indigestible marker to determine the apparent total tract retention (ATTR) of the gross energy (GE), dry matter, acid-hydrolyzed ether extract, nitrogen, neutral detergent fiber, acid detergent fiber, ash, and minerals. The results indicate that the ATTR of Ca in the aged laying hens with SES (59.7%) was greater (p < 0.05) than in the aged laying hens with WES (48.6%). However, the ATTR of the GE and other nutrients was not different between the hens with SES or WES. There were no differences in the ATTR of GE and nutrients between the hens with DBE or LBE. In conclusion, aged laying hens with SES have a greater ability to utilize dietary Ca than those with WES, indicating that the extent of dietary Ca utilization determines the eggshell strength of aged laying hens. However, nutrient utilization in diets may have little impact on eggshell brown coloration in aged laying hens.