• 한국식품저장유통학회지
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• 제17권6호
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• pp.820-825
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• 2010

본 연구에서는 경제적 측면에서 일반 소금보다 우수한 해양심층수 소금을 이용하여 간장을 제조한 후 발효기간에 따른 품질특성을 조사하였다. pH와 완충능은 발효가 진행됨에 따라 점차 감소하였다. 순추출물의 함량은 점차 증가하여 발효 120일째에 7.5%로 나타났다. 간장의 갈색화는 발효 30일 째에 대부분의 갈색화가 진행되었다. 총질소와 아미노태 질소는 발효가 진행됨에 따라 점차 증가하여 발효 12일째 각각 1.4%와 0.75%를 나타내었다. 유리아미노산의 함량은 179.8~315.7 mg%가 검출되었으며, 발효기간이 증가함에 따라 점차 함량이 증가하였다. 발효 전 기간에 걸쳐 glutamic acid가 가장 많았으며, alanine, lysine 및 leucine의 순으로 많았다. 총 유리 아미노산에 대한 glutamic acid의 비율은 21.0~23.2%였으며, 필수아미노산의 함량은 발효 30일째에 78~142.3 mg%가 검출되었으며, 발효가 진행됨에 따라 그 함량도 증가하였다.

• 정보과학회 논문지
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• 제43권7호
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• pp.827-833
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• 2016

HTTP 적응적 스트리밍은 네트워크 상태에 따라 비디오의 품질을 조절하여 사용자 체감 품질을 향상시키는 비디오 스트리밍 서비스이다. HTTP 적응적 스트리밍 서비스에서 비디오 콘텐츠는 여러 품질과 일정 길이를 가지는 비디오 세그먼트로 나누어지며, 클라이언트는 적절한 품질의 세그먼트를 요청한다. 그러나 기존의 세그먼트 스케줄러는 TCP에 대한 고려 없이 일정 간격으로 세그먼트를 요청하므로 TCP 연결이 초기화되어 Slow-start를 다시 수행해 비디오 전송률이 감소한다. 본 논문에서는 HTTP 적응적 스트리밍 서비스의 품질을 향상시키기 위한 TCP 인지형 세그먼트 스케줄링 기법을 제안한다. 제안하는 기법은 TCP 연결이 초기화되는 것을 방지하기 위해 비디오 세그먼트의 요청 시간을 조절하며, 세그먼트를 요청하는 시점을 고려하여 안정적인 비디오 스트리밍을 수행한다. 시뮬레이션을 통해 제안하는 기법이 끊김 현상 없이 HTTP 적응적 스트리밍 서비스의 품질을 향상시키는 것을 확인하였다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.150.2-150
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• 1999

To investigate the weathering soil buffering capacities of the artificial acidic precipitation, the weathering soils and their leachate solutions were sampled from the host rocks(granite;GR, rhyolite;RH, gabbro;GA, basalt;BA, two serpentinite;SE1, SE2 and limestone;LI) and analyzed for pH and chemical properties. 1n the soil pH of the GR and RH ,the acidic rocks, were 5.02 and 5.95, respectively. And the GA and BA, basic rocks, were 6.52 and 7.57. The SE1 and SE2 were 8.90 and 8.89. While the LI was 7.84. These results means the typical soil pH properties by host rocks. After the artificial acidic precipitation input 5OOml, the average changes of soil leachate solutions treated by pH levels(pH 5.0, 4.0 and 3.0), were pH 5.73, 5.00 and 4.40. in GR soil, and pH 6.19, 5.99 and 5.57 in RH. GA were pH 6.31, 6.04 and 5.86, BA were pH 7.05, 6.85 and 6.56 and SE1 were pH 8.31, 8.26 and 7.71. SE2 were pH 8.29, 8.24 and 7.96. LI were pH 7.55, 7.46 and 6.79. The soil leachate pHs from volcanic rocks were higher than those from the plutonic rocks and GR soils showed greater response than other soils. With increasing 100ml input-solution, the soil leachate pHs were mainly decreased. Cation concentrations, CEC, EC and total nitrogen concentrations of RH and BA soils, the volcanic rocks, were higher than those of GR and GA soil, the plutonic rocks. On the contrary, Al concentrations of the GR and GA soils were higher than those of RH and BA soils, partly because of high quartz content in GR and Al content in the biotite and plagioclase in GA.

• 한국재료학회지
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• 제32권4호
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• pp.216-222
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• 2022

The capacity of high nickel Li(Ni_xCo_yMn_1-x-y)O₂ (NCM, x ≥ 0.8) cathodes is known to rapidly decline, a serious problem that needs to be solved in a timely manner. It was reported that cathode materials with the {010} plane exposed toward the outside, i.e., a radial structure, can provide facile Li⁺ diffusion paths and stress buffer during repeated cycles. In addition, cathodes with a core-shell composition gradient are of great interest. For example, a stable surface structure can be achieved using relatively low nickel content on the surface. In this study, precursors of the high-nickel NCM were synthesized by coprecipitation in ambient atmosphere. Then, a transition metal solution for coprecipitation was replaced with a low nickel content and the coprecipitation reaction proceeded for the desired time. The electrochemical analysis of the core-shell cathode showed a capacity retention of 94 % after 100 cycles, compared to the initial discharge capacity of 184.74 mA h/g. The rate capability test also confirmed that the core-shell cathode had enhanced kinetics during charging and discharging at 1 A/g.

• 한국토양비료학회지
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• 제6권4호
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• pp.221-226
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• 1973

현(現) 비료(肥料) 공정규격(公定規格)에 보증성분(保證成分)이 미달(未達)되는 규회석(珪灰石)의 비효(肥效) 및 규회석(珪灰石)의 가용(可溶) 규산분석법(珪酸分析法)을 검토(檢討)코져, 가용규산함량(可溶珪酸含量)이 상이(相異)한 수종(數種)의 규회석(珪灰石) 및 규회석(珪灰石)과 가용성규산(可溶性珪酸)을 함유(含有)하지 않은 암석(岩石)의 혼합분말(混合粉末)을 광재(鑛滓)와 대조(對照)하여 벼에 대한 재배시험(栽培試驗)을 수행(遂行)하여 규산(珪酸)의 흡수량(吸收量)을 조사(調査)하고, 공시(供試) 규회석(珪灰石)을 수종(數種)의 완형용액(緩衡溶液)에 침출(浸出)하여 규산가용율(珪酸可溶率)과 식물체(植物體)가 흡수(吸收)한 규산함량(珪酸含量)과 상관관계(相關關係) 및 규회석(珪灰石)의 X-선회절분석(線回折分析)을 하여 다음과 같은 결과(結果)를 얻었다. 1. 가용성(可溶性) 규산함량(珪酸含量)(N/2 HCl)이 높은 규회석(珪灰石)일수록 식물체중의 규산함량 및 흡수량(吸收量)을 증가(增加)시켰다. 2. 광재(鑛滓) 처리구(處理區)의 벼 짚중(中) 규산흡수량(珪酸吸收量)은 가용성(可溶性) 규산함량(珪酸含量)이 4.1%인 규회석분말구(珪灰石粉末區)와 같이 가장 낮았다. 3. 가용성(可溶性) 규산함량(珪酸含量)이 높은 규회석(珪灰石)에 잡석(雜石)을 혼합(混合)하여 시비(施肥)하여도 수도체(水稻體)의 규산함량(珪酸含量)은 동량(同量)의 가용성규산함량(可溶性珪酸含量)을 함유(含有)한 규회석(珪灰石)과 같은 효과이었다. 4. 각종(各種) 완형용액(緩衡溶液)에 침출(浸出)된 가용규산(可溶珪酸)과 짚중(中) 규산함량(珪酸含量) 및 흡수량(吸收量)과는 고도(高度)의 유의성(有意性)이 있는 정(正)의 상관(相關)이었으며 N/2염산(鹽酸) 침출규산(浸出珪酸) 분석법(分析法)도 규회석(珪灰石)의 규산분석법(珪酸分析法)으로써 충분(充分)히 사용(使用)될 수 있는 방법(方法)이었다. 5. 규회석(珪灰石)의 X-선(線) 회절(回折)은 규회석(珪灰石)의 조성(造成)을 찾아낼 수 있으며, 결정(結晶)이 불량(不良)한 규회석(珪灰石) 일수록 가용규산함량(可溶珪酸含量)이 높았다.

• 한국응용과학기술학회지
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• 제32권2호
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• pp.202-214
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• 2015

Stimuli-responsive biomaterials that alter their function through sensing local molecular cues may enable technological advances in the fields of drug delivery, gene delivery, actuators, biosensors, and tissue engineering. In this research, pH-responsive hydrogel which is comprised of dimethylaminoethyl methacylate (DMAEMA) and 2-hydroxyethyl methacrylate (HEMA) was synthesized for the effective delivery of doxorubicin (Dox) to breast cancer cells. Cancer and tumor tissues show a lower extracellular pH than normal tissues. DMAEMA/HEMA hydrogels showed significant sensitivity by small pH changes and each formulation of hydrogels was examined by scanning electron microscopy, mechanical test, equilibrium mass swelling, controlled Dox release, and cytotoxicity. High swelling ratios and Dox release were obtained at low pH buffer condition, low cross-linker concentration, and high content of DMAEMA. Dox release was accelerated to 67.3% at pH 5.5 for 6-h incubation at $37^{\circ}C$, while it was limited to 13.8% at pH7.4 at the same time and temperature. Cell toxicity results to breast cancer cells indicate that pH-responsive DMAEMA/HEMA hydrogels may be used as an efficient matrix for anti-cancer drug delivery with various transporting manners. Also, pH-responsive DMAEMA/HEMA hydrogels may be useful in therapeutic treatment which is required a triggered release at low pH range such as gene delivery, ischemia, and diabetic ketoacidosis.

• 한국식품영양과학회지
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• 제23권6호
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• pp.945-949
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• 1994

Chondroitin sulfate (Chs) contents in edible snail , Achatina fulica Bowdich , andits processed meat extracts were determined by high-performance liquid chormatogrpahy(HPLC) and spectrophotometric method. Spectrophotometric method was based on the precipitation of acriflavine by ChS, and HPLC method was based on the detection of two unsaturated disaccharides, 2-acetamido-2-deoxy-3-O-($\beta$ -D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose($\Delta$Di-4S) and 2-acetamido-2deoxy-3-O-($\beta$-D-gluco-4-eepyranosyluronic acid)-6-O-sulfo-D-galactose ($\Delta$야-6S) librated from ChS byenzymeatic digestion with chondroitinase ABc. the ratio of 125$\mu$mol of sodium hydroxide to mg of ChS and 8$0^{\circ}C$ of reaction temperature were proper for alkaline hydrolysis to remove protein residue form ChS. In assay preparation for HPLC ethod, the iptimum concentration of the enzyme chondroitinase ABc was 0.15 unit per 50 $\mu\textrm{g}$ of ChS at a fixed reaction time (30 min) and pH 8.0 using Tris buffer. ChS content in edible snail was 177.6mg% by spectrophotometric method and 153.5mg% by HPLC method and those in the processed meat extract was 71.3mg% by spectrometric method ad 62.8mg% by HPLC method, respectively.

• 한국식품영양과학회지
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• 제12권1호
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• pp.1-6
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• 1983

인삼(人蔘)과 오가피중(五加皮中)의 핵산계(核酸系) 성분(成分)을 HPLC로 분리(分離) 정량(定量)하여 다음과 같은 결과를 얻었다. 1. 동일한 원료수삼에서 제조한 백삼(白蔘)과 홍삼(紅蔘)의 핵산유리염기(核酸遊離鹽基)와 nucleoside의 조성이 거의 같았다. 2. 인삼(人蔘)과 오가피(五加皮)중의 nucleosides 함량에서 adenosine, guanosine, cytidine 등이 특징적(特徵的)인 차이(差異)를 나타냈으며 인삼속(人蔘屬)이 약(約) 3배(倍)이상 많게 나타났다. 그러나 tymidine과 inosine은 오가피속(五加皮屬)이 다소 많았다. 3. nucleobase 함량면에서는 인삼(人蔘)이나 오가피간(五加皮間)에 비슷한 함량으로 1~2mg/100g를 함유했다.

• Advances in Traditional Medicine
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• 제8권2호
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• pp.178-186
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• 2008

In this study, ionotropic gelation method was used for the preparation of ibuprofen-loaded calcium alginate (CALG) and ethylenediamine (EDA) treated calcium alginate (EDA-CALG) microspheres. The effect of EDA-treatment on drug entrapment efficiency, particle size, morphology, swelling behavior and in vitro release characteristics of the microspheres was investigated by varying its concentration from 0.5 to 2% (v/v). The reduction in drug entrapment efficiency by a maximum of 44.60% was noted for EDA-CALG microspheres compared to untreated CALG microspheres. The particle size and swelling index of EDA-CALG microspheres were reduced with increasing EDA concentration. All the microspheres were observed to retain their spherical shapes with rough surfaces. EDA-CALG microspheres prepared using 1% and 2% v/v EDA, released almost all of its content within 7 h in pH 6.8 phosphate buffer, however, CALG microspheres were found to release the same within 3 h. The intensity of melting endothermic peak of ibuprofen reduced significantly at lower drug load as experienced from DSC thermograms. The FT-IR spectrum of pure ibuprofen, ibuprofen-loaded CALG and EDA-CALG microspheres showed the characteristic band of C = O stretching vibration of ibuprofen. Hence, this study revealed that EDA can be employed for the preparation of ibuprofen-loaded CALG microspheres to retard the drug release to some extent.

• BMB Reports
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• 제30권5호
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• pp.346-351
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• 1997

The maximum adsorption/desorption conditions and the adsorption mechanism of globular proteins to vaccine adjuvants were determined. The maximum adsorption ratio of protein to the $Al^{3+}$ content of aluminum oxyhydroxide and the optimal adsorption pH are 2:1 (${\mu}g:{\mu}g$) for bovine serum albumin (BSA) at pH 6.0 and 2.5:1 (${\mu}g:{\mu}g$) for immunoglobulin G (IgG) at pH 7.0, respectively. The maximum adsorption ratio onto aluminum phosphate gel was 1.5:1 (${\mu}g$ Protein:${\mu}g$ $Al^{3+}$) at pH 5.0 for both BSA and IgG. Adsorption of the native globular proteins, BSA and IgG, to aluminum oxyhydroxide and aluminum phosphate gel was reversible as a function of pH. Complete desorption of these proteins from aluminum phosphate gel was observed at alkaline pH, whereas only 80~90% removal from aluminum oxyhydroxide was achieved with alkaline pH and 50 mM phosphate buffer. We conclude that electrostatic and hydrogen bonding interactions between the native proteins and adjuvants are important binding mechanisms for adsorption, and that the surface charge of the protein and the colloid components control the maximum adsorption conditions.