• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.4
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• pp.8-15
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• 2012

Optical property improvements for ONP (old newspaper) and OMG (old magazine) were attempted by application of in-situ $CaCO_3$ formation process on recycled fiber surfaces. Washing treatment of ONP and OMG resulted in 35~40% yield loss for around 6% brightness improvement. Washing plus bleaching process with $H_2O_2$ and FAS (formamidine sulfinic acid) improved brightness and ERIC values a little more with the same amount of yield loss as washing treatment. In-situ $CaCO_3$ formation method improved those optical properties much better than the washing plus bleaching method without loss of yield, and better than the case of adding high brightness PCC up to the same ash level. It can be said that the in-situ $CaCO_3$ formation method may be used as an effective alternative for upgrading optical properties of recycled fibers.

• Journal of Soil and Groundwater Environment
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• v.27 no.1
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• pp.60-70
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• 2022

We evaluated the performance of in-situ capping to prevent the release of phenol, one of hazardous chemicals of concern for their impact on sediment. Sediment near the estuary of Hyeongsan River, Korea, and commercially-available sand were collected to evaluate their physical properties and phenol sorption characteristics. Biodegradation kinetics of phenol spiked into the sediment was evaluated under freshwater and estuarine salinity conditions. These experimental measurements were parameterized and used as input parameters for executing CapSim, a software predicting the performance of in-situ capping. The CapSim simulation demonstrated that capping with 50-cm sand reduced the phenol release by several orders of magnitude over 0.25- and 1-year duration for almost all simulation scenarios. The variables tested, i.e., cap thickness, pore-water movement, and biodegradation rate, showed high correlation to each other to influence the extent of phenol release from sediment to the water column. The findings and the framework employed to evaluate the performance of in-situ capping in this study can be adopted to determine whether in-situ capping is appropriate remedial approach at sediment sites impacted by hazardous chemicals due to accidental spills.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.103.2-103.2
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• 2012

알루미늄기지 복합재료는 낮은 밀도, 높은 비강도, 우수한 강성을 가지고 있어서 수송기기용 경량소재로서 적용 가능하다. 강화재를 외부에서 주입하는 ex-situ 법에 비하여 화학반응에 의하여 강화상이 생성되는 in-situ 법은 기지와 강화상의 계면 특성이 우수하다. In-situ 주조법으로 제조한 알루미늄기지 복합재료는 여러 형태로 가공하기 위하여 압출, 열간압연 등의 공정을 거치게 되므로 열간가공성에 대한 이해가 필요하다. 이 연구에서는 고온압축시험을 이용하여 in-situ $Al/TiC_p$ 복합재료의 열간가공성을 평가하였다. 고온유동곡선으로부터 변형률속도민감도를 구하였으며 Dynamic Material Model을 이용하여 efficiency of power dissipation을 표현하는 공정지도를 작성하였다. 또한 변형 조건에 따른 미세조직 발달 거동을 조사하였으며 이로부터 각 변형 구간에 대한 변형기구를 도출하였다. 이로부터 알루미늄기지 복합재료의 열간가공성에 미치는 강화상의 영향을 고찰하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.506-509
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• 2004

We have investigated the generation of pretilt angle for a nematic liquid crystal (NLC) alignment with in-situ photoalignment method on polyimide (PI) surfaces using thin plastic substrates. The LC aligning capabilities and pretilt angle of the thin plastic substrates by in-situ photoalignment method were better than that of the glass substrate by general photoalignment. Also, the LC pretilt angle increased with increasing heating temperature and exposure time. And EO characteristics of photoaligned TN-LCDs using in-situ photodissociation method on glass substrate and on plastic substrate are also excellent.

• Journal of Animal Science and Technology
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• v.49 no.3
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• pp.351-358
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• 2007

This experiment was conducted to determine correlation between in vitro protein fractions and in situ protein degradation rate with major dairy protein sources(soybean meal, corn gluten meal, cotton seed meal, kapok seed meal and perilla meal). Five protein fractions were obtained according to the Cornell Net Carbohydate and Protein System(CNCPS), and in situ protein degradation rates were determined by technique using nylon bags incubated for 0, 4, 8, 12 and 24hrs in the rumen of three Holstein steers. Fraction A was highest in kapok seed meal(14.6%) and lowest in corn gluten meal(0.6%) (P<0.05). The highest B1, B2 and B3 fractions were contained in soybean meal(8.27%), cotton seed meal(74%), and perilla meal(40%), respectively. Corn gluten meal was very high in fraction C. In situ protein degradation rate of soybean meal was 98%, highest among five protein sources, and corn gluten meal had the lowest rate at 28%. Correlation analysis showed that easily soluble fractions of both methods, in situ protein degradation rate and digestible protein fractions, and in situ protein degradation rate minus “a” and fraction B2+B3 were highly correlated. These results indicate that in vitro protein fractionation can be used in the estimation of in situ protein degradation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.269-274
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• 2013

This study is conducted to estimate the nutrient compositions and in-situ ruminal disappearancerates of roughage sources which are commonly used in South Korea. Twelve types of roughage sources are being selected based on surveys from more than 50 farms, and 12 samples from various farms and companies are collected and analyzed for their nutritive components and minerals. Two Hanwoo steers (BW $526{\pm}14$ kg) with ruminal cannula are used to investigate in situ ruminal degradability. Five roughage sources, timothy hay, alfalfa pellet, rice straw, klein grass hay and tall fescue straw, are all selected from 12 roughage sources above for further experiments. Overall, the nutrient components and minerals from the 12 roughage sources have shown low values when comparing with standard tables of feed compositions in Korea. In situ dry matter disappearance rate is recorded as high in order of klein grass, timothy, alfalfa pellet, tall fescue and rice straw. In situ crude protein disappearance rate is high in order of alfalfa pellet, klein grass, timothy, tall fescue and rice straw.

• Journal of the Korea Institute of Building Construction
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• v.21 no.5
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• pp.445-457
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• 2021

In previous studies, it was confirmed that through the in-situ production of precast concrete members, costs could be reduced by 14.5-39.4% compared to in-plant production. In particular, it was confirmed that the factory owner did not make a contract if it did not earn more than 20% of the production cost. If precast concrete members are produced in-situ under the same conditions, the quality equivalent to that of factory production can be secured. As it is advantageous in terms of cost and quality, precast concrete members must be produced in-situ. However, it is difficult to produce all quantities in-situ due to time and various other constraints. This is because in-situ production is avoided due to anticipated risks during the project management process. However, if the risk factors are analyzed before performing in-situ production of precast concrete members, it will increase the opportunity for in-situ production. Therefore, this study develops a checklist for evaluating the risk of in-situ production of precast concrete members. By applying the checklist to one case site, it was verified that risk factors can be evaluated easily and quickly. As a result, it was analyzed that sites with a high building coverage ratio are classified as high-risk sites because it is difficult to secure usable area for production and storage. The developed checklist efficiently evaluates the risk factors of in-site production, and makes it possible for the operator to determine the risk factors, which can change frequently during project execution, and respond according to the situation.

• Journal of Radiation Protection and Research
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• v.43 no.3
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• pp.85-96
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• 2018

Background: A variety of inorganic scintillators have been developed and improved for use in radiation detection and measurement, and in situ gamma-ray spectrometry in the environment remains an important area in nuclear safety. In order to verify the feasibility of promising scintillators in an actual environment, a performance test is necessary to identify gamma-ray peaks and calculate the radioactivity from their net count rates in peaks. Materials and Methods: Among commercially available scintillators, $LaBr_3(Ce)$ scintillators have so far shown the highest energy resolution when detecting and identifying gamma-rays. However, the intrinsic background of this scintillator type affects efficient application to the environment with a relatively low count rate. An algorithm to subtract the intrinsic background was consequently developed, and the in situ calibration factor at 1 m above ground level was calculated from Monte Carlo simulation in order to determine the radioactivity from the measured net count rate. Results and Discussion: The radioactivity of six natural radionuclides in the environment was evaluated from in situ gamma-ray spectrometry using an $LaBr_3(Ce)$ detector. The results were then compared with those of a portable high purity Ge (HPGe) detector with in situ object counting system (ISOCS) software at the same sites. In addition, the radioactive cesium in the ground of Jeju Island, South Korea, was determined with the same assumption of the source distribution between measurements using two detectors. Conclusion: Good agreement between both detectors was achieved in the in situ gamma-ray spectrometry of natural as well as artificial radionuclides in the ground. This means that an $LaBr_3(Ce)$ detector can produce reliable and stable results of radioactivity in the ground from the measured energy spectrum of incident gamma-rays at 1 m above the ground.

• Biomedical Science Letters
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• v.2 no.2
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• pp.249-255
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• 1996

In this paper, a in situ hybridization(ISH) has been used to investigate the yield of viral RNA expression from each organ tissues. It is studied to establish a rapidly, specific diagnostic method detecting rabbit haemorrhagic disease virus(RHDV) RNA in 10% formalin-fixed, paraffin-em-bedded tissues of naturally RHDV-infected rabbits using oligonucleotide probe to be made by RHDV total sequences. Biotin was used as the oligonucleotide probe marker. in situ hybridization is detected the virus genome in the cells and tissue as specifically compared with others nucleic acid hybridization method. All ISH procedure of RHDV were completed to Mi-croProbe$^{TM}$ capillary action system within 1-2 hours. In this report, RHDV was distributed widely in the cytoplasm of liver cell and the cortex of kidney but lung tissue and medulla of kidney were showed to positive reaction at locally. Although not entirely free of technical limitations, nucleic acid identification holds advantages over other diagnostic tests, including exquisite sensitivity, specificity, interchangeability and speed. It is expected that, in the immediate future viral nucleic acid detection will be a prominent part of the methods used in histopathology.

• Journal of Korea Foundry Society
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• v.17 no.2
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• pp.170-179
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• 1997

A noble technique has been developed for fabricating in situ formed $TiC_p/Al$ composites. In this process, fairly stable TiC particles were in situ synthesized in liquid aluminum by the interfacial reaction between an Al-Ti melt and SiC, which is a comparatively unstable carbide from the view-point of thermodynamics. It is possible in the present process to generate TiC particles of nearly 1 ${\mu}m$ in diameter, even utilizing SiC of 14 ${\mu}m$ as raw material. However, the dispersion behavior of TiC particles in the matrix depends on the size of the raw material SiC. Decomposing finer SiC makes the dispersion of TiC particles more uniform and the mechanical properties of composites are improved accordingly. The structure of in situ composites and their mechanical properties are affected by the fabrication temperature and the stirring time. It has been found that the most suitable condition for fabrication should be applied depending on the size of the raw material, even if the same kinds of carbide are used. Furthermore, although Al-Ti-Si system intermetallic compounds are detected in a $TiC_p/Al-Si$ composite which is fabricated by conventional melt-stirrng method, these compounds can not be observed in a $TiC_p/Al-Si$ composite made by this in situ production method. Hence the mechanical properties of the in situ $TiC_p/Al-Si$ composite are superior to those of the conventional $TiC_p/Al-Si$ composites.