• 한국환경과학회지
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• 제14권7호
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• pp.675-681
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• 2005

A laboratory experiment was performed to investigate phosphorus and nitrogen removal from synthetic wastewater by intermittently aerated activated sludge process packed with aluminum and silver plate. Three continuous experi­mental processes, i. e. an intermittently aerated activated sludge process(Run A), an intermittently aerated activated sludge process with an aluminum and silver plate packed into the reactor(Run B), and a reactor post stage(Run C) were compared. In the batch experiments, the phosphorus removal time in the reactor packed with aluminum and silver plate simultaneously was faster than that of the reactor packed with only an aluminum plate. More phos­phorus was removed with an increase of NaCl concentration. The pitting corrosion of aluminum does not affect the performance of the biological treatment. The total nitrogen removal efficiency in Run B was $57\%\;and\;43.6\%$ at the HRT of 12 and 6 hours respectively. The effluent $PO_{4-}P$ concentration as low as 1.0 mg/L could be ob­tainable through the continuous experiment in Run B at HRT of 6 hours.

• 한국식품영양과학회지
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• 제12권2호
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• pp.150-175
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• 1983

The paper is to classify the terms of foods, wines, relish(komyungs), seasonings and cooking processes in Korean cooking books. The results of this study are follows : The dishes which were made from cereals are Bab(boiled cooked rice), Juk(gruel), Miuem(Thin rice gruel), Noodle, Sujebee, Mandu(Pyun su, dumpling), D'ockuk, Pumbok, Yaksik, D'ock(Korean rice cake) etc. The terms of side dishes are Tang (Kuk, Kaeng), Chigae(Jochi Kamjeang, Jijimee, Tugari, Wakjeoji), Jim(Jeung), Sun, Jungol(Abok jaeng ban, sinsulro, punggujigol), Bockum, Kui, Jorim, Cho, Jun(Jijim, Jeenya, Puchigae, Bindae-dock, Nureumi) Jeok(San-jeok, Nuremjeok, Jijimnureumjeok), Hoe (Saenghoe, Sukhoe, Kanghoe, Sujeonghoe, A chae), Mareum chan (Po, Jaban), Changachi (Jangkwa, Sukchae (namul)-Japchae, Kyujachae), Muchim, Sam, Tuigim, Pyunyuk, sundae, suran, Jeockal (Sikhae), Jockpyun, Mal-i, Jihi, Kee, Pojeok, Gimchi etc. The kinds of Jabgwas are Kangieong(Sanja), Yumilgwa, Suksilgwa, Dasik, Jeonggwa, Yeocgangjeong, Gwapyun etc. The kinds of beverages are Hwachaes and Teas. The terms of the wines in Korean cooking bok are 173 kinds. There are 21 kinds of Relish(komyung). There are 12 kinds of Jang, and the terms of the seasonings are as follows: mustard, cinammon, pep per, powder of peppers, powder of sesame, honey, garlic, ginger, sugar, salt, vinegar, syrup, yunjeup, jochung, sesamol-oil, chojeckuk, sesame, greet-onion, powder of black pepper, oil etc. There are 547 kinds of prepared cooking terms, 36 kinds of cutting terms and 34 kinds of boiling term in food making terms.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.966-970
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• 2010

본 연구의 대상지인 인천광역시, 부천시, 서울특별시, 김포시를 걸쳐서 흐르는 굴포천은 산업화와 도시화로 인한 생활하수 및 공장폐수의 유입, 느린 유속과 하천 복개 등과 같은 유입오염원과 하천 구조적 문제로 인하여 수질이 악화되어 왔다. 특히 하천변의 소규모 영세 공장, 중 상류에 형성된 대규모 공업단지, 지역개발에 따른 인구증가로 인한 생활하수 등은 굴포천의 주 오염원이다. 또한 직강화된 하도와 느린 유속 등 하천의 구조적인 문제점 등은 하천의 자정능력을 저하시키고 있어 현재 굴포천의 수질수준은 전국 최하위에 머물러 있다. 더욱이 입자상 오염물질의 퇴적으로 인하여 굴포천의 하상은 대부분 퇴적오니가 형성되어 있다. 이러한 퇴적오니는 다량의 유기 물질 및 중금속 등을 흡착하고 있고, 재용출에 의한 내부오염 가능성을 내포하고 있기 때문에 오염원이 제거된 후에도 계속적인 수질오염을 일으킬 수 있다(Alloway et al, 1988). 따라서 본 연구에서는 굴포천 본류 전 구간 및 유입지천에 대하여 수질 오염도와 오염부하량을 산정하였으며, 본류 하상 퇴적물의 오염도 및 퇴적물의 용출특성에 관한 조사를 수행하였다. 본 연구는 굴포천 본류 구간을 최상류(GP-1)부터 최하류(GP-7)구간까지 총 7개 구간으로 구분하여 실시하였으며 각 지점별 수질 및 퇴적물 오염도를 조사하였다. 또한 3개의 유입지천에 대하여 수질 오염도 및 오염부하량을 산정하였다. 굴포천 하상의 경우 최상류의 GP-1지점을 제외하고는 전 구간이 대부분 오염된 오니가 퇴적되어 있으며, 이러한 퇴적오니의 퇴적물 오염도를 분석해본 결과 상류부인 GP-1, GP-2와 유속이 비교적 빠른 GP-7지점에 비하여 나머지 지점들의 오염도가 매우 높은 것으로 나타났다. 이러한 하상퇴적물의 영양염류 용출특성을 알아보기 위하여 호기 및 혐기조건에서 용출실험을 실시한 결과 호기와 혐기 조건에서 T-N은 각각 34.84 $mg/m^2/day$, 66.93 $mg/m^2/day$의 용출속도를 보였고, T-P의 경우 호기 조건 시 5.33 $mg/m^2/day$, 혐기 조건 시 6.84 $mg/m^2/day$의 용출속도를 보임으로서 퇴적물 용출에 의한 내부오염의 가능성이 있음을 보였다.

• 한국식품과학회지
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• 제3권2호
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• pp.89-93
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• 1971

전국 각지의 토양 800점에서 총 1,506주의 균을 분리하였고 이들중에서 응유효소 생산균으로 20주의 균을 선정하였으며 교실보존 균들 중의 응유효소 생산균을 선정하여 응유효소 생산력을 비교하였으며 이들중 보존균 중의 Dothiorella ribis가 비교적 우수한 응유효소생산균임을 알고 이것을 밀기울에 배양할 때의 배양조건을 검토한 결과 밀기울에 대한 산수량은 $60{\sim]80%$ 산수의 pH는 4.0 정도, 질소원으로는 $(NH_4)_2SO_4$ 0.5%, 탄소원으로는 sucrose 3%정도, 무기염으로는 0.03%, 배양온도는 $30{\sim}35^{\circ}C$, 배양기간은 4일 정도가 적당함을 알 수 있었고 보다 장기간 배양하면 생성된 응유효소의 활성이 감퇴됨을 알수 있었다.

• 한국세라믹학회지
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• 제49권6호
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• pp.586-591
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• 2012

$Zr_2WP_2O_{12}$ powder, which has a negative thermal expansion coefficient, was synthesized by a solid-state reaction with $ZrO_2$, $WO_3$ and $NH_4H_2PO_4$ as the starting materials. The synthesis behavior was dependent on the solvent media used in the wet mixing process. The $Zr_2WP_2O_{12}$ powder prepared with a solvent consisting of D. I. water was fully crystallized at $1200^{\circ}C$, showing a sub-micron particle size. According to the results obtained from a thermal analysis, a $ZrP_2O_7$ was synthesized at a low temperature of $310^{\circ}C$, after which it was reacted with $WO_3$ at $1200^{\circ}C$. A new sintering additive, $Al(OH)_3$, was applied for the densification of the $Zr_2WP_2O_{12}$ powders. The cold isostatically pressed samples were densified with 1 wt% $Al(OH)_3$ additive or more at $1200^{\circ}C$ for 4 h. The main densification mechanism was liquid-phase sintering due to the liquid which resulted from the reaction with amorphous or unstable $Al_2O_3$ and $WO_3$. The densified $Zr_2WP_2O_{12}$ ceramics showed a relative density of 90% and a negative thermal expansion coefficient of $-3.4{\times}10^{-6}/^{\circ}C$. When using ${\alpha}-Al_2O_3$ as the sintering agent, densification was not observed at $1200^{\circ}C$.

• Journal of Information Processing Systems
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• 제8권3호
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• pp.495-520
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• 2012

A secure Electronic Payment System (EPS) is essential for the booming online shopping market. A successful EPS supports the transfer of electronic money and sensitive information with security, accuracy, and integrity between the seller and buyer over the Internet. SET, CyberCash, Paypal, and iKP are the most popular Credit Card-Based EPSs (CCBEPSs). Some CCBEPSs only use SSL to provide a secure communication channel. Hence, they only prevent "Man in the Middle" fraud but do not protect the sensitive cardholder information such as the credit card number from being passed onto the merchant, who may be unscrupulous. Other CCBEPSs use complex mechanisms such as cryptography, certificate authorities, etc. to fulfill the security schemes. However, factors such as ease of use for the cardholder and the implementation costs for each party are frequently overlooked. In this paper, we propose a Web service based new payment system, based on ANSI X9.59-2006 with extra features added on top of this standard. X9.59 is an Account Based Digital Signature (ABDS) and consumer-oriented payment system. It utilizes the existing financial network and financial messages to complete the payment process. However, there are a number of limitations in this standard. This research provides a solution to solve the limitations of X9.59 by adding a merchant authentication feature during the payment cycle without any addenda records to be added in the existing financial messages. We have conducted performance testing on the proposed system via a comparison with SET and X9.59 using simulation to analyze their levels of performance and security.

• Genomics & Informatics
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• 제3권3호
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• pp.86-93
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• 2005

Human brain EST data provide important clues for our understanding of the molecular biology associated with the function of the normal brain and the molecular pathophysiology with brain disorders. To systematically and efficiently study the function and disorders of the human brain, 45,773 human brain ESTs were collected from 27 human brain cDNA libraries, which were constructed from normal brains and brain disorders such as brain tumors, Parkinson's disease (PO) and epilepsy. An analysis of 45,773 human brain ESTs using our EST analysis pipeline resulted in 38,396 high-quality ESTs and 35,906 ESTs, which were coalesced into 8,246 unique gene clusters, showing a significant similarity to known genes in the human RefSeq, human mRNAs and UniGene database. In addition, among 8,246 gene clusters, 4,287 genes ($52\%$) were found to contain full-length cONA clones. To facilitate the extraction of useful information in collected these human brain ESTs, we developed a user-friendly interface system, the Korea Brain Unigene Database (KBUD). The KBUD web interface allows access to our human brain data through three major search modes, the BioCarta pathway, keywords and BLAST searches. Each result when viewed in KBUD offers comprehensive information concerning the analyzed human brain ESTs provided by our data as well as data linked to various other publiC databases. The user-friendly developed KBUD, the first world-wide web interface for human brain EST data with ESTs of human brain disorders as well as normal brains, will be a helpful system for developing a better understanding of the underlying mechanisms of the normal brain well as brain disorders. The KBUD system is freely accessible at http://kugi.kribb.re.kr/KU/cgi -bin/brain. pI.

• 한국환경복원기술학회지
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• 제13권6호
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• pp.97-106
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• 2010

Earthworm, a prominent ecosystem engineer within many terrestrial ecosystems, can exert profound influences on various abiotic/biotic environments through bioturbation processes such as burrowing, casting and mixing of litter and soil. In this study, we investigated how the presence or absence of earthworm (Oligochaeta) can alter the soil physico-chemical conditions and ultimately the distribution and abundance of Collembola which constitutes a large proportion of the soil fauna. During September 2010, soil organisms along with soil samples were collected from randomly installed 20 plots in Mt. Gwan-ak. We examined the differences in the abundance of Collembola among plot samples in respect to the presence/absence of earthworm and soil physico-chemical conditions (i.e., pH, $PO_4^{3-}$, $NO_3^{2-}$, organic matter (OM), electrical conductance and water content). Analysis of soil physico-chemical environment revealed a significantly higher organic matter content and electrical conductance in plots with earthworm compared to plots without earthworm. Abundance of Collembola were not only higher in plots with earthworm than in plots without earthworm, but were also positively correlated with availability of OM present in the environment. The results suggest that positive impacts of earthworm on the abundance of Collembola in this study may have been due to their ability to effectively modify soil physico-chemical conditions favored by Collembola. Such conspicuous influence of earthworm's activity on below-ground community suggests their potential significance in forest restoration or revegetation process.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권6호
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• pp.1-11
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• 2017

This study was conducted to investigate the performance of four commercial chemical agents in stabilizing arsenic (As) in soil at the forest area near the former Janghang smelter site. After amending the stabilizing agents (A, B, C, and D) into As-contaminated soil samples, synthetic precipitation leaching procedure (SPLP) and solubility bioavailability research consortium (SBRC)-extractable As concentrations significantly decreased except for agent D, which is mainly composed of fly ash and calcium carbonate. Increase of SPLP and SBRC-extractable As concentrations in four soil samples (S1, S2, S3, and J2) was attributed to desorption of As adsorbed on iron oxides due to high pH generated by agent D. It is therefore necessary to consider application conditions according to soil characteristics such as pH and buffering capacity. Results of sequential extraction showed that readily extractable fractions of As in soil (i.e., sum of $SO_4-$ and $PO_4-extractable$ As in soil) were converted into non-readily extractable fractions by amending agents A, B, and C. Such changes in the As distribution in soil resulted in the decrease of SPLP and SBRC-extractable As concentration. A series of follow-up monitoring and management plan has been suggested to assess the longevity of the stabilization treatments in the site.

• 한국도로학회논문집
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• 제18권1호
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• pp.43-55
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• 2016

PURPOSES : This study aims to develop a repair material that can enhance pavement performance, inducing rapid traffic opening through early strength development and fast setting time by utilizing MgO-based patching materials for repairing road pavements. METHODS : To consider the applicability of MgO-based patching materials for repairing domestic road pavements, first, strength development and setting time of the materials were evaluated, based on MgO to $KH_2PO_4$ ratio, water to binder ratio, and addition ratio of retarder (Borax), by which the optimal mixture ratio of the developed material was obtained. To validate the performance of the developed material as a repair material, the strength(compressive strength and bonding strength) and durability (freezing, thawing, and chloride ion penetration resistance) was checked through testing, and its applicability was evaluated. RESULTS : The results showed that when an MgO-based patching material was used, the condensation time was reduced by 80%, and the compressive strength was enhanced by approximately 300%, as compared to existing cement-based repair materials. In addition, it was observed that the strength (compressive strength and bonding strength) and durability (freezing and thawing, and chloride ion penetration resistance) showed an excellent performance that satisfied the regulations. CONCLUSIONS : The results imply that an emergent repair/restoration could be covered by a rapid-hardening cement to meet the traffic limitation (i.e. the traffic restriction is only several hours for repair treatment). Furthermore, MgO-based patching materials can improve bonding strength and durability compared to existing repair materials.