• Title/Summary/Keyword: various applications

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Effects of Gamma Irradiation on Color Changes and Biological Activities of Ethanol Extract of a Mechanically Pressed Juice of Bokbunja (Rubus coreanus Miq.) (감마선 조사에 의한 복분자 착즙액 에탄올 추출물의 색상 및 생리활성 변화)

  • Kim, Hee-Jung;Jo, Cheor-Un;Kim, Hyun-Joo;Shin, Dong-Hwa;Son, Jun-Ho;Byun, Myung-Woo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.3
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    • pp.271-277
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    • 2006
  • A mechanically pressed juice of Bokbunja (Rubus coreanus Miq.) extract was prepared using 70% ethanol solution. The extract was subjected to gamma-irradiation treatment (20 kGy) and investigated for its change of color and biological activities. Hunter $L^*$ values of the irradiated Bokbunja extract were increased in comparison with the non-irradiated extracts, and the $a^*\;and\;b^*$values decreased by the irradiation treatment. The content of the total phenolic compounds in the non-irradiated and irradiated extracts were 58.4 and 56.5 mg/g, respectively. The 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical scavenging activities of non-irradiated and irradiated extracts at a 250 ppm level were 80% and 79%, respectively. Lipid oxidation was retarded by addition of Bokbunja powder. Nitrite scavenging activity was the highest in the Bokbunja powder at pH 1.2 and the effect was not changed by irradiation. The Bokbunja powder showed antimicrobial activity against Salmonella Typhimurium and Bacillus cereus. However, irradiation of Bokbunja did not affect any physiological functions (p>0.05). A Salmonella mutagenicity assay indicated that the irradiated Bokbunja extract did not show any mutagenicity. Therefore, Bokbunja extract could be used in various applications as a functional material, such as ingredients of food and cosmetic, compositions with functions.

Antibacterial and Antioxidative Activities of Epimedium koreanum Nakai Extracts (삼지구엽초 추출물의 항균 및 항산화 활성에 대한 연구)

  • Won, Doo Hyun;Gu, Hyun A;Kim, Hye Jin;Han, Saet Byeol;Park, Jino;Park, Soo Nam
    • Microbiology and Biotechnology Letters
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    • v.41 no.3
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    • pp.284-291
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    • 2013
  • In this study, the antibacterial and antioxidative activities of Epimedium koreanum Nakai were investigated for applications as cosmetic ingredients. Minimum inhibitory concentrations (MICs) of fraction-bacterium, that showed high antibacterial activity from disc diffusion assay on human skin pathogens, were tested. The ethyl acetate fraction on Staphylococcus aureus, Bacillus subtilis, Propionibacterium acnes and 50% ethanol extract on S. aureus exhibited higher antibacterial activities than methyl paraben, well known as a preservative. The DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging activities of 3 fractions of E. koreanum Nakai were lower than (+)-${\alpha}$-tocopherol, known as a typical antioxidant. From the results of the scavenging activities of various ROS generated in $Fe^{3+}-EDTA/H_2O_2$ systems ($OSC_{50}$), 50% ethanol extract ($OSC_{50}=2.46{\pm}0.06{\mu}g/ml$) and aglycone fraction ($OSC_{50}=1.45{\pm}0.02{\mu}g/ml$) showed high activities similar to L-ascorbic acid ($OSC_{50}=1.50{\pm}0.85{\mu}g/ml$), used as reference. The cellular protective effects (${\tau}_{50}$) on photohemolysis by $^1O_2$ generated by photosensitization reaction were tested. The cellular protective effect of 50% ethanol extract (${\tau}_{50}=37.0{\pm}0.3$ min) was similar to (+)-${\alpha}$-tocopherol (${\tau}_{50}=38.0{\pm}1.8$ min), used as reference. In particular, the ${\tau}_{50}$ of aglycone fraction results were $165.9{\pm}7.2$ min. This is a high cellular protective effect, more than 4 times that of (+)-${\alpha}$-tocopherol. These results indicate that E. koreanum Nakai extract, and its fractions, could be utilized as a cosmetic ingredient possessing antibacterial and antioxidative activities.

Variation of Fatty Acid Composition in Soybean'Pungsannamul' Mutation Population from EMS Treatment (EMS 처리에 의한 풍산나물 콩 돌연변이 집단에서 지방산 조성 변이)

  • Chae, Jong-Hyun;Dhakal, Krishna Hari;Asekova, Sovetgul;Song, Jong Tae;Lee, Jeong-Dong
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.1
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    • pp.45-50
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    • 2013
  • Mutagenesis is used to study gene function and obtain new genetic resources for plant breeding. Soybean is an important oil crop in the world. Thus, to find new genetic resources, a mutation population was developed from the soybean cultivar Pungsannamul using 0.3% ethyl methane sulfonate. The variation of fatty acids was then evaluated among 892 M4 generation mutant lines selected from 3,774 mutant lines. While the wild type Pungsannamul showed 11.6, 3.4, 23.8, 53.3, and 7.8% for palmitic, stearic, oleic, linoleic and linolenic acid, respectively. the fatty acid variations in the mutant lines ranged from 7.4 to 19.7%, 2.2 to 13.0%, 14.7 to 49.0%, 31.8 to 63.9%, and 3.9 to 15.9% with an average of 10.8, 3.8, 25.3, 52.0, and 8.1% for palmitic, stearic, oleic, linoleic and linolenic acid, respectively. Thus, two mutation lines with higher plamitic acid, PE1542 (17.1%) and PE3058 (17.0%), one line with lower stearic acid, PE2166 (1.9%), one line with higher stearic acid, PE977 (12.7%), two lines with higher oleic acid, PE450 (44.4%) and PE2742 (47.7%), and two lines with lower linolenic acid, PE594 (4.6%) and PE1690 (3.7%), were selected from this study. The newly selected fatty acid variants will be good genetic sources for gene function analyses and breeding soybean varieties with altered fatty acids for various industrial and human food applications.

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Old Service Pipe Cleaning of Polly-pigs Cleaning technique (Polly-pigs를 이용한 노후급수관의 세관에 관한 연구)

  • Lee, Hyun-Dong;Bae, Chul-Ho;Park, Jeong-Hoon;Kim, Gil-Nam
    • Journal of Korean Society on Water Environment
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    • v.18 no.3
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    • pp.303-312
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    • 2002
  • Polly-pigs technique was developed to remove internal rusts and scales from service pipes in the building by using Polly-pigs that were used as various applications in conventional plant pipelines. Results of cleaning experiments on 15mm GSP(Galvanic Steel Pipe) showed that hydraulic cross sectional area was more increased from 3.5% to 15.4% for straight part or elbow parts of several test pieces. Results of optical analysis also showed that rust and scale removed mostly by KDP series(only consisted of Polyurethane) were outside red colored scale ($Fe_2O_3{\cdot}H_2O$), and there was a limitation to the removal of black colored scale($Fe_2O{\cdot}nH_2O$) that was below red colored scale. But it was evaluated that KDPS series coated fine sand with KDP series could remove not only red colored scale but also black colored scale and more increase hydraulic cross sectional areas of 15mm GSP old service pipes from 13.0% to 17.9%. After KDPS series cleaning, hydraulic cross sectional areas of them were recovered from 95.9% to 99.5%. Turning force of Polly-pigs was largely improved by the effect of Helical guide vane(Cleaning v/v) and Rotating wing(Pigs), and the number of pig rotating also more increased sixteen times compared with conventional cleaning system without Helical guide vane and Rotating wing. After KDPC series cleaning of 100mm GSP old service pipes that hydraulic cross sectional areas were 90%, hydraulic cross sectional areas were almost recovered perfectly like new service pipes. Additionally pressure necessary to run Polly-pigs m 100mm GSP was lower and cleaning efficiency also was higher than 15mm GSP cleaning. Therefore it was thought that as the diameter of pipe was more increased, pressure necessary to clean service pipes was more decreased and cleaning efficiency was more increased in Polly-pigs cleaning.

용용과 모델 구성을 중시하는 수학과 교육 과정 개발 방안 탐색

  • Jeong Eun Sil
    • The Mathematical Education
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    • v.30 no.1
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    • pp.1-19
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    • 1991
  • This study intends to provide some desirable suggestions for the development of application oriented mathematics curriculum. More specific objects of this study is: 1. To identify the meaning of application and modelling in mathematics curriculm. 2. To illuminate the historical background of and trends in application and modelling in the mathematics curricula. 3. To consider the reasons for including application and modelling in the mathematics curriculum. 4. To find out some implication for developing application oriented mathematics curriculum. The meaning of application and modelling is clarified as follows: If an arbitrary area of extra-mathematical reality is submitted to any kind of treatment which invovles mathematical concepts, methods, results, topics, we shall speak of the process of applying mathemtaics to that area. For the result of the process we shall use the term an application of mathematics. Certain objects, relations between them, and structures belonging to the area under consideration are selected and translated into mathemtaical objects, relation and structures, which are said to represent the original ones. Now, the concept of mathematical model is defined as the collection of mathematical objcets, . relations, structures, and so on, irrespective of what area is being represented by the model and how. And the full process of constructing a mathematical model of a given area is called as modelling, or model-building. During the last few decades an enormous extension of the use of mathemtaics in other disciplines has occurred. Nowadays the concept of a mathematical model is often used and interest has turned to the dynamic interaction between the real world and mathematics, to the process translating a real situation into a mathematical model and vice versa. The continued growing importance of mathematics in everyday practice has not been reflected to the same extent in the teaching and learning of mathematics in school. In particular the world-wide 'New Maths Movement' of the 19608 actually caused a reduction of the importance of application and modelling in mathematics teaching. Eventually, in the 1970s, there was a reaction to the excessive formallism of 'New Maths', and a return in many countries to the importance of application and connections to the reality in mathematics teaching. However, the main emphasis was put on mathematical models. Applicaton and modelling should be part of the mathematics curriculum in order to: 1. Convince students, who lacks visible relevance to their present and future lives, that mathematical activities are worthwhile, and motivate their studies. 2. Assist the acqusition and understanding of mathematical ideas, concepts, methods, theories and provide illustrations and interpretations of them. 3. Prepare students for being able to practice application and modelling as private individuals or as citizens, at present or in the future. 4. Foster in students the ability to utilise mathematics in complex situations. Of these four reasons the first is rather defensive, serving to protect or strengthen the position of mathematics, whereas the last three imply a positive interest in application and modelling for their own sake or for their capacity to improve mathematics teaching. Suggestions, recomendations and implications for developing application oriented mathematics curriculum were made as follows: 1. Many applications and modelling case studies suitable for various levels should be investigated and published for the teacher. 2. Mathematics education both for general and vocational students should encompass application and modelling activities, of a constructive as well as analytical and critical nature. 3. Application and modelling activities should. be introduced in mathematics curriculum through the interdisciplinary integrated approach. 4. What are the central ideas of, and what are less-important topics of application-oriented curriculum should be studied and selected. 5. For any mathematics teacher, application and modelling should form part of pre- and in-service education.

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Adsorption of Arsenic on Goethite (침철석(goethite)과 비소의 흡착반응)

  • Kim, Soon-Oh;Lee, Woo-Chun;Jeong, Hyeon-Su;Cho, Hyen-Goo
    • Journal of the Mineralogical Society of Korea
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    • v.22 no.3
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    • pp.177-189
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    • 2009
  • Iron (oxyhydr)oxides commonly form as secondary minerals of high reactivity and large surface area resulting from alteration and weathering of primary minerals, and they are efficient sorbents for inorganic and organic contaminants. Accordingly, they have a great potential in industrial applications and are also of substantial interest in environmental sciences. Goethite (${\alpha}$-FeOOH) is one of the most ubiquitous and stable forms of iron (oxyhydr)oxides in terrestrial soils, sediments, and ore deposits, as well as a common weathering product in rocks of all types. This study focused on adsorption reaction as a main mechanism in scavenging arsenic using goethite. Goethite was synthesized in the laboratory to get high purity, and a variety of mineralogical and physicochemical features of goethite were measured and related to adsorption characteristics of arsenic. To compare differences in adsorption reactions between arsenic species, in addition, a variety of experiments to acquire adsorption isotherm, adsorption edges, and adsorption kinetics were accomplished. The point of zero charge (PZC) of the laboratory-synthesized goethite was measured to be 7.6, which value seems to be relatively higher, compared to those of other iron (oxyhydr)oxides. Its specific surface area appeared to be $29.2\;m^2/g$ and it is relatively smaller than those of other (oxyhydr)oxides. As a result, it was speculated that goethite shows a smaller adsorption capacity. It is likely that the affinity of goethite is much more larger for As(III) (arsenite) than for As(V) (arsenate), because As(III) was observed to be much more adsorbed on goethite than As(V) in equivalent pH conditions. When the adsorption of each arsenic species onto goethite was characterized in various of pH, the adsorption of As(III) was largest in neutral pH range (7.0~9.0) and decreased in both acidic and alkaline pH conditions. In the case of As(V), the adsorption appeared to be highest in the lowest pH condition, and then decreased with an increase of pH. This peculiarity of arsenic adsorption onto goethite might be caused by macroscopic electrostatic interactions due to variation in chemical speciation of arsenic and surface charge of goethite, and also it is significantly affected by change in pH. Parabolic diffusion model was adequate to effectively evaluate arsenic adsorption on goethite, and the regression results show that the kinetic constant of As(V) is larger than that of As(III).

Parameterization and Application of a Forest Landscape Model by Using National Forest Inventory and Long Term Ecological Research Data (국가산림자원조사와 장기생태연구 자료를 활용한 산림경관모형의 모수화 및 적용성 평가)

  • Cho, Wonhee;Lim, Wontaek;Kim, Eun-Sook;Lim, Jong-Hwan;Ko, Dongwook W.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.22 no.3
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    • pp.215-231
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    • 2020
  • Forest landscape models (FLMs) can be used to investigate the complex interactions of various ecological processes and patterns, which makes them useful tools to evaluate how environmental and anthropogenic variables can influence forest ecosystems. However, due to the large spatio-temporal scales in FLMs studies, parameterization and validation can be extremely challenging when applying to new study areas. To address this issue, we focused on the parameterization and application of a spatially explicit forest landscape model, LANDIS-II, to Mt. Gyebang, South Korea, with the use of the National Forest Inventory (NFI) and long-term ecological research (LTER) site data. In this study, we present the followings for the biomass succession extension of LANDIS-II: 1) species-specific and spatial parameters estimation for the biomass succession extension of LANDIS-II, 2) calibration, and 3) application and validation for Mt. Gyebang. For the biomass succession extension, we selected 14 tree species, and parameterized ecoregion map, initial community map, species growth characteristics. We produced ecoregion map using elevation, aspect, and topographic wetness index based on digital elevation model. Initial community map was produced based on NFI and sub-alpine survey data. Tree species growth parameters, such as aboveground net primary production and maximum aboveground biomass, were estimated from PnET-II model based on species physiological factors and environmental variables. Literature data were used to estimate species physiological factors, such as FolN, SLWmax, HalfSat, growing temperature, and shade tolerance. For calibration and validation purposes, we compared species-specific aboveground biomass of model outputs and NFI and sub-alpine survey data and calculated coefficient of determination (R2) and root mean square error (RMSE). The final model performed very well, with 0. 98 R2 and 8. 9 RMSE. This study can serve as a foundation for the use of FLMs to other applications such as comparing alternative forest management scenarios and natural disturbance effects.

Design and Implementation of an Execution-Provenance Based Simulation Data Management Framework for Computational Science Engineering Simulation Platform (계산과학공학 플랫폼을 위한 실행-이력 기반의 시뮬레이션 데이터 관리 프레임워크 설계 및 구현)

  • Ma, Jin;Lee, Sik;Cho, Kum-won;Suh, Young-kyoon
    • Journal of Internet Computing and Services
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    • v.19 no.1
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    • pp.77-86
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    • 2018
  • For the past few years, KISTI has been servicing an online simulation execution platform, called EDISON, allowing users to conduct simulations on various scientific applications supplied by diverse computational science and engineering disciplines. Typically, these simulations accompany large-scale computation and accordingly produce a huge volume of output data. One critical issue arising when conducting those simulations on an online platform stems from the fact that a number of users simultaneously submit to the platform their simulation requests (or jobs) with the same (or almost unchanging) input parameters or files, resulting in charging a significant burden on the platform. In other words, the same computing jobs lead to duplicate consumption computing and storage resources at an undesirably fast pace. To overcome excessive resource usage by such identical simulation requests, in this paper we introduce a novel framework, called IceSheet, to efficiently manage simulation data based on execution metadata, that is, provenance. The IceSheet framework captures and stores each provenance associated with a conducted simulation. The collected provenance records are utilized for not only inspecting duplicate simulation requests but also performing search on existing simulation results via an open-source search engine, ElasticSearch. In particular, this paper elaborates on the core components in the IceSheet framework to support the search and reuse on the stored simulation results. We implemented as prototype the proposed framework using the engine in conjunction with the online simulation execution platform. Our evaluation of the framework was performed on the real simulation execution-provenance records collected on the platform. Once the prototyped IceSheet framework fully functions with the platform, users can quickly search for past parameter values entered into desired simulation software and receive existing results on the same input parameter values on the software if any. Therefore, we expect that the proposed framework contributes to eliminating duplicate resource consumption and significantly reducing execution time on the same requests as previously-executed simulations.

Liability of Air Carrier and its Legislative Problems in China : Some proposals for its Amendments (중국 항공운송법의 현황 및 주요내용과 앞으로의 전망 : 항공운송인의 책임을 중심으로)

  • Li, Hua
    • The Korean Journal of Air & Space Law and Policy
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    • v.26 no.1
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    • pp.147-176
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    • 2011
  • China is experiencing rapid economic development and the volume of air passengers and cargo transportation has increased significantly in recent years. To the contray, the regulations on liability of air carrier in china fall behind and are not sufficiently applicable in disputes. Their lack of sufficient protection for air passenger's interests became obstructive factor for further developments of Chinese air transportation industry. The legal system of air carrier's liability mainly consists of the contents as followed. The liability period, the scope of liability, amount of compensation for damage, limitation of liability, liability exemption of air carrier, jurisdiction, limitation of action, applicable law etc. Laws and rules concerning these issues are regulated in Civil Aviation Law and regulations published by Civil Aviation Administration of China. This article described the main contents of air carrier's liability and examined the legislative problems in their applications in real cases. In order to solve the legal problems on the air carrier's liability and disputes between wrongdoers and survivors etc, it is necessary and desirable for china to amend revelvant provisions. One of my proposals is to raise the amount of compensation limitation for damage. And I also would like to suggest that Civil Aviation Law should treat international and domestic transportation equally on the limitation of compensation for air carrier's liability. China has also acceded to the Montreal Convention of 1999 on July 31, 2005. This is an effort to make the law of air carriage unified worldwide through various international conventions to achieve conformity between rules of international air carriage and that of Chinese domestic aircarriage. Furthermore, there should be additional detailed implementation rules for air carrier to assume liability for the losses to passengers, baggage or cargoes caused by delays in the air transport. Significant clarifications are also needed for provisions concerning whether and how air carrier assume liability for moral damage caused by accident.

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Predicting the Performance of Recommender Systems through Social Network Analysis and Artificial Neural Network (사회연결망분석과 인공신경망을 이용한 추천시스템 성능 예측)

  • Cho, Yoon-Ho;Kim, In-Hwan
    • Journal of Intelligence and Information Systems
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    • v.16 no.4
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    • pp.159-172
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    • 2010
  • The recommender system is one of the possible solutions to assist customers in finding the items they would like to purchase. To date, a variety of recommendation techniques have been developed. One of the most successful recommendation techniques is Collaborative Filtering (CF) that has been used in a number of different applications such as recommending Web pages, movies, music, articles and products. CF identifies customers whose tastes are similar to those of a given customer, and recommends items those customers have liked in the past. Numerous CF algorithms have been developed to increase the performance of recommender systems. Broadly, there are memory-based CF algorithms, model-based CF algorithms, and hybrid CF algorithms which combine CF with content-based techniques or other recommender systems. While many researchers have focused their efforts in improving CF performance, the theoretical justification of CF algorithms is lacking. That is, we do not know many things about how CF is done. Furthermore, the relative performances of CF algorithms are known to be domain and data dependent. It is very time-consuming and expensive to implement and launce a CF recommender system, and also the system unsuited for the given domain provides customers with poor quality recommendations that make them easily annoyed. Therefore, predicting the performances of CF algorithms in advance is practically important and needed. In this study, we propose an efficient approach to predict the performance of CF. Social Network Analysis (SNA) and Artificial Neural Network (ANN) are applied to develop our prediction model. CF can be modeled as a social network in which customers are nodes and purchase relationships between customers are links. SNA facilitates an exploration of the topological properties of the network structure that are implicit in data for CF recommendations. An ANN model is developed through an analysis of network topology, such as network density, inclusiveness, clustering coefficient, network centralization, and Krackhardt's efficiency. While network density, expressed as a proportion of the maximum possible number of links, captures the density of the whole network, the clustering coefficient captures the degree to which the overall network contains localized pockets of dense connectivity. Inclusiveness refers to the number of nodes which are included within the various connected parts of the social network. Centralization reflects the extent to which connections are concentrated in a small number of nodes rather than distributed equally among all nodes. Krackhardt's efficiency characterizes how dense the social network is beyond that barely needed to keep the social group even indirectly connected to one another. We use these social network measures as input variables of the ANN model. As an output variable, we use the recommendation accuracy measured by F1-measure. In order to evaluate the effectiveness of the ANN model, sales transaction data from H department store, one of the well-known department stores in Korea, was used. Total 396 experimental samples were gathered, and we used 40%, 40%, and 20% of them, for training, test, and validation, respectively. The 5-fold cross validation was also conducted to enhance the reliability of our experiments. The input variable measuring process consists of following three steps; analysis of customer similarities, construction of a social network, and analysis of social network patterns. We used Net Miner 3 and UCINET 6.0 for SNA, and Clementine 11.1 for ANN modeling. The experiments reported that the ANN model has 92.61% estimated accuracy and 0.0049 RMSE. Thus, we can know that our prediction model helps decide whether CF is useful for a given application with certain data characteristics.