• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2008.02a
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• pp.99-102
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• 2008

차세대 이동 통신 서비스 4G는 이동 중 100Mbps, 정지 중 1Gbps급 전송 속도를 제공하는 미래 무선 통신 기술이다. 이것은 현재 상용서비스가 이뤄지고 있는 3G HSDPA(High Speed Packet Access)의 전송속도 14Mbps에 비해 10~100배까지 빠른 속도로 무선 인터넷이 가능함으로 유선으로 인터넷을 사용할 필요가 없어진다. 현재 4G 기술로 진화하기 위한 중간 단계로써 ITU-R, 3GPP, 3GPP2, IEEE 등 세계 각국의 표준 및 기술 단체에서 새로운 무선 이동 통신 기술을 제안하고 있다. 이 중에서 2G의 GSM과 3G의 비동기식 기술 WCDMA의 진화 기술인 3GPP LTE(Long Term Evolution) 및 SAE(System Architecture Evolution)가 유력한 4G 이동 통신 기술 후보로 평가 받고 있다. 본 논문에서는 4G 기술로 주목 받고 있는 3GPP LTE 및 SAE 네트워크에서 3G 시스템 보다 진화된 서비스를 제공하기 위한 목적으로 논의되고 있는 일반적인 요구사항과 이를 만족시키기 위한 기술에 대하여 알아본다. 또한 LTE 표준화와 병행하여 네트워크의 구조를 결정하는 SAE의 구성요소와 프로토콜 구조를 소개하고 LTE 및 SAE 네트워크의 보안위협과 안전한 통신을 위한 키 관리 방법에 대하여 논의한다.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.468-474
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• 1989

The cultural condition for polysaccharide production by Pseudomonus detafietdii was studied. The optimal medium contains the following composition per liter of distilled water: glucose (25g/$\ell$), peptone (2.06g/$\ell$), KH$_2$PO$_4$(2g/$\ell$), MgSO$_4$.7$H_2O$ (2g/$\ell$), yeast extract (0.5g/$\ell$), CaCO$_3$(2.5g/$\ell$). The temperature and pH optimum were 3$0^{\circ}C$ and 6.5. The agitation speed was 300 rpm. 5.91g of polysaccharide was produced at the condition in flask culture.

• Culinary science and hospitality research
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• v.17 no.4
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• pp.295-306
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• 2011

This study aims to increase the flavor of a lamb filet dish. The method used was as follows. Four kinds of crusts(mustard, herb & garlic, nuts, mushrooms) were made, and they were topped over lamb filet steaks. After cooking them, the good samples (mustard(MU3), herb & garlic(HG2), nuts(NC2), mushrooms(MC3)) by different materials through a sensory test were classified The selected samples were named as 1. Blank, 2. ECl(MU3), 3. EC2(HG2), 4. EC3(NC2), and 5. EC4(MC3). And then another sensory test was conducted targeting the samples to find out which crust had the best preference value. The results of the sensory test were statistically calculated Summarizing the results, all 4 kinds of samples topped with 4 different crusts showed much higher values than Blank, the control group. That indicates that the cooking method topping a crust on a lamb filet steak dish is very effective. Among them, the HG2 sample produced by mixing 70% of bread crumbs(115.5g) and 30% of garlic chop(49.5) with the base spice consisting of parsley 8g, rosemary 3g, basil 4g and olive oil 50g was evaluated as the best crust.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.879-885
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• 2008

This study was conducted to analyze 15 traditional Korean gruels for nutrient density using the Index of Nutrient Quality (INQ). The calorie of the gruels ranged from 148.8 (Daechujuk) to 294.1 kcal (Jatjuk) per serving size. The calorie in 'Jatjuk' was the highest, covering 33.3% of Dietary Reference Intakes for Koreans (KDRI) per meal. The carbohydrate content was between 23.0 g (Dakjuk) and 52.1 g (Patjuk) per serving size. The average content of carbohydrate in gruels was $34.7{\pm}9.1\;g per serving size which covers 24.4% of KDRI per meal. Among the 15 gruels, Patjuk contained the highest carbohydrate content (52.1 g per serving size, 36.7% of KDRI per meal). The highest nutrient density (INQ) of carbohydrate in gruels was Dachujuk (INQ 1.4). The protein content of the gruels was between 2.3 (Huinjuk) and 22.3 g (Dakjuk) per serving size. The average content of protein in gruels was 25.6% of KDRI per meal. Dakjuk contained the highest protein content ($8.2{\pm}4.9\;g$ per serving size) and followed by Dakjuk (INQ 2.5), Guljuk (INQ 1.5) and Kongjuk (INQ 1.3) in nutrient density (INQ) of protein. The fat content of the gruels were between 0.3 (Daechujuk) and 17.8 g (Jatjuk) per serving size. The average content of fat in gruels was $17.8{\pm}0.12\;g$ per serving size which showed 21.1% of KDRI per meal. Among the gruels, Jatjuk contained the highest fat ($17.8{\pm}0.12\;g$ per serving size, 77.4% of KDRI per meal). In order of the high nutrient density (INQ) of protein, Jatjuk (INQ 2.4) was followed by Heugimjajuk (INQ 1.5) and Kongjuk (INQ 1.5).

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.89-96
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• 2000

Waste oyster shell was used to study the applicability on anaerobic composting of garbage. Experiment was conducted with five anaerobic reactors. After garbage and compost for inoculation were mixed, waste oyster shell was added into mixed waste in mesophillic temperature for 60 days with 30%, 60% respectively. The amount of produced methane gas, gas composition, organic removal efficiency and pH were measured. Result showed that the amounts of produced gas were 0.62 l /g-VS in R-1, 0.63 l /g-VS in R-2, 0.16 l /g-VS in R-3, 0.75 l /g-VS in R-4, 0.21 l /g-VS in R-5 and the amounts of produced methane gas were 0.32 l /g-VS in R-1, 0.37 l /g-VS in R-2, 0.04 l /g-VS in R-3, 0.42 l /g-VS in R-4, 0.05 l /g-VS in R-5. Proportion of mathane gas which determines the efficiency of anaerobic composting was over 55%. pH were 6.0~8.0 in R-2 and R-4 which contained 30% of waste oyster shell and pH were increased over 8.5 in R-3 and R-5 which contained 60% of waste oyster shell. Since pH were so high and it had a negative effect on microbial growth, anaerobic reaction were not well operated in R-3 and R-5.

• Current Applied Physics
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• v.18 no.11
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• pp.1458-1464
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• 2018

An improved method for the preparation of g-$C_3N_4$ is described. Currently, heating (> $400^{\circ}C$) of urea is the common method used for preparing the g-$C_3N_4$. We have found that sonication of melamine in $HNO_3$ solution, followed by washing with anhydrous ethanol, not only reduce the crystallite size of g-$C_3N_4$ but also facilitate intriguing electronic structure and photoluminescence (PL) properties. Moreover, loading of metal (Pt and Ag) nanoparticles, by applying the borohydride reduction method, has resulted in multicolor-emission from g-$C_3N_4$. With the help of PL spectra and local electronic structure study, at C K-edge, N K-edge, Pt L-edge and Ag K-edge by X-ray absorption spectroscopy (XAS), a precise mechanism of tunable luminescence is established. The PL mechanism ascribes the amendments in the transitions, via defect and/or metal states assimilation, between the ${\pi}^*$ states of tris-triazine ring of g-$C_3N_4$ and lone pair states of nitride. It is evidenced that interaction between the C/N 2p and metal 4d/5d orbitals of Ag/Pt has manifested a net detraction in the ${\delta}^*{\rightarrow}LP$ transitions and enhancement in the ${\pi}^*{\rightarrow}LP$ and ${\pi}^*{\rightarrow}{\pi}$ transitions, leading to broad PL spectra from g-$C_3N_4$ organic semiconductor compound.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.5
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• pp.315-323
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• 2008

To measure the mineral content of fishes, we collected 177 individuals from 53 fish species from the east (Pohang), west (Gunsan), and south (Tongyeong) coasts of Korea. The mean content of the macro mineral in a 100 g sample taken from the edible portion of each fish was (in descending order): P(207.4 mg), K(169.7 mg), Na(101.6 mg), Ca(44.4 mg), and Mg(30.4 mg). In comparison, the mean content of micro mineral in the fishes was (in descending order): Zn ($8.98{\mu}g/g$), Fe ($5.03{\mu}g/g$), Cu ($0.76{\mu}g/g$), Mn ($0.43{\mu}g/g$), and Ni ($0.08{\mu}g/g$). We could not observe clear regional variation in the mineral content of fish species. With regard to minerals considered essential for humans, the amount of Ca per sample (100 g) was the highest in the Scyliorhinus torazame (465.4 mg), and than followed by Ammodytes personatus (338.0 mg), Dasyatis akajei (267.4 mg), Raja kenojei (248.1 mg), Conger myriaster (174.1 mg), Clupanodon punctatus (86.8 mg), Muraenesox cinereus (81.2 mg), and Engraulis japonica (70.4 mg). The daily average intake of the mineral through the fishes consisted of P (100.6 mg), K (82.3 mg), Na (49.3 mg), Mg (14.8 mg), Zn (0.44 mg), Fe (0.24 mg), Cu (0.04 mg) and Mn (0.02 mg). The respective intakes of macro mineral (P, Mg, Na, Ca, K) from the fishes were about 14.4, 4.2, 3.3, 3.1 and 1.8% of the dietary reference intakes for Koreans (KDRIs) set by the Korean Nutrition Society. In comparison, the respective intakes of micro mineral (Cu, Zn, Fe, Mn) from the fishes were about 4.6, 4.4, 2.4, and 0.6% of the KDRIs.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.169-178
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• 1984

This experiment was conducted to find out selective herbicides which are safe to the rice seedlings and to provide effective weed control method in protected semi-irrigated rice seedbed. There was no crop injury in rice with benzophenap [2-(4-2, 4-dichloro-3-methylbenzoyl)-1, 3-dimethyl-pyrazol-5-yl-oxy)-4'-methyl acetophenone] (240g), pyrazoxyfene [1,3-dimethyl-4-(2,4-dichlorobenzoyl)-Sphenacyloxy pyrazole] (200g), chlormethoxynil [2,4-dichlorophenyl-4-nitro-3-methoxyphenyl ether] (180g), dimepiperate [S-(1-methyl-1-phenethyl)-piperidine-l-carbathioate] (210g), dimepiperate + probenazol [3-allyloxy-1,2-benzisothiazol-1,1-dioxide] (210 + 120g) mixture and dimepiperate + probenazol + molinate [S-ethyl-N,N-hexamethylene-thiol-carbamate] (120 + 120 + 120g) mixture at times of application studied. Butachlor [2-chloro-2',6'-diethyl-N-buthoxymethyl acetanilide] + pyrazolate [4-(2,4-dichlorbenzoyl)-1,3dimethyl-pyrazol-5-yl-p-toluene-sulfonate] (70 + 120g) mixture and butachlor + chlormethoxynil (60 + 120g) mixture caused root length to shorten and root viability to decrease. However, the crop injury was recovered at 25 days after seeding. Benzophenap, pyraxoxyfene and butachlor + pyrazolate mixture were effective for weed control when applied at 2 days before seeding. Chlormethoxynil and butachlor + chlormethoxynil mixture was very effective for controlling annual weed. Dimepiperate, dimepiperate + probenazol mixture and dimepiperate + probenazol + molinate mixture did not control most weeds except for Echinochloa crus-galli (L.) Beauv.

• Food Science of Animal Resources
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• v.28 no.1
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• pp.21-26
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• 2008

This study was carried out to evaluate the nutritional properties of spreadable liver product. The composition of fresh hog liver used as raw material was 70.5% moisture, 5.2% fat, 20.3% protein and 1.2% ash. The composition of the spreadable liver product was 55.3% moisture, 19.4% protein, 21.6% fat and 3.7% ash. The total amino acid content of fresh liver was 18.69 g/100 g with glutamic acid at the highest level of 2.57 g/100 g. The total amino acid content of liver product was 18.03 g/100 g with glutamic acid at 2.28 g/100 g. The essential amino acid content was found to be 42% of total amino acids. The fatty acid analysis of fresh liver revealed oleic acid to be present at the highest level of 28% in the unsaturated fatty acid portion, and palmitic acid to be highest at 20.7% in the saturated fatty acid portion. The oleic acid content of the liver product was 40%, and the palmitic acid content was 20.4%. The level of cholesterol in fresh liver was 178.0 mg/100 g compared to 118.0 mg/100 g in the liver product. Regarding mineral analysis, the K and P contents of fresh liver were 362.2 mg/100 g and 339.1 mg/100 g, respectively, and 336.1 mg/100 g and 213.3 mg/100 g in the liver product, respectively. Many other minerals including Na, Mg, Ca and Fe were present in the product. Based on these results, the spreadable liver product made with hog liver was found to be a quality food with nutritional benefits and that is easy to consume.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.48-53
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• 2007

This study was carried out to investigate the effect of $NO_3{^-}$ and $NH_4{^+}$ on the adventitious root growth and eleuthroside synthesis of Eleutherococcus senticosus during 3 L-bioreactor culture. The change of medium component ratio was also measured during culture. The fresh weignt of adventitious root reached to the greatest level of 24.4g FW/L in the presence of 50 mM $NO_3{^-}$ and 10 mM $NH_4{^+}$, representing 3.4-fold increase compared to the 60 mM $NH_4{^+}$. However, as the increase of the portion of $NH_4{^+}$, the root growth was decreased. Maximum eleutheroside B and E1 production were $249{\mu}g/g$ and $43{\mu}g/g$, respectively, with 30 mM total nitrogen source. The maximum production of eleutheroside E were $788{\mu}g/g$ with 120 mM total nitrogen source. The greatest weight of adventitious root increased up to 6.2 fold of inoculum size within 9 weeks. The change of pH was influenced from 4.81 to 6.35 and the amounts of $NH_4{^+}$ and $K^+$ were decreased during culture periods. From these results we suggest, need further study of various treatment to increase the growth of biomass and the accumulation of useful secondary metabilites.