• Title/Summary/Keyword: smart society

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The Relationships among Perceived Value, Use-Diffusion, Loyalty of Mobile Instant Messaging Service (모바일 메신저 서비스의 지각된 가치, 사용-확산 그리고 충성도 간의 관계에 대한 연구)

  • Jo, Dong-Hyuk;Park, Jong-Woo;Chun, Hyun-Jae
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.193-212
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    • 2011
  • Mobile instant messaging service is surfacing to an important keyword in the mobile market together with popularization of Smart phones. Mobile instant messaging service in Korea has become popular to the degree of 87.9% usages from total Smartphone holders, and it is expected that using populations will be more enlarged afterwards if considering a fact that its populations of Smartphone is continuously being increased after exceeding 10 million persons (Trend Monitor, June 2011). In the instant messaging market where competitions have been deepened day by day, raising customer's royalties will be the key for company's business survivals and goals of corporate marketing strategies. It could be said that understanding on which factors affect to customer retentions and royalties is very important. Specially, as changing status is being progressed very quickly in case of innovative mobile services like the instant messaging service, research necessities on how many do consumers use the services after accepting them, how much do consumers use them variously, and whether does it connect to long-term relations have been increased, but studies on such matters are in insufficient situations actually. Therefore, this study examined on which effects were affected to use-diffusion and loyalty factors from perceived customer vales' factors having been occurred after accepting the mobile instant messaging service, namely 'functional value', 'monetary value', 'emotional value', and 'social value'. Also, the study looked into what kind of roles do the service usage and using variety play to service's continued using intents as a loyalty index, recommending intents to others, and brand switching intents. And then the study laid the main purpose in trying to provide implications for enhancing customer securities and royalties on the mobile instant messaging service through research's results. The research hypotheses are as follows; H1: Perceived values will affect influences to royalties. H2: Use-Diffusion will affect influences to loyalty. H3: Perceived value will affect influences to loyalty. H4: The use-diffusion will play intermediating roles between perceived values and loyalty. Total 276 cases among collected 284 ones were used for the statistical analysis by SPSS ver. 15 package. Reliability, Factor analysis, regression were done. As the result of research, 'monetary value' and 'emotional value' affected to 'usage' among perceived value factors, and 'emotional value' was appeared as affecting the largest influence. Besides, the usage affected to constant-using intents and recommending intents to others, and using varieties were displayed as affecting to recommending intents to others. On the other hand, 'Using' and 'Using diversity' were appeared as not affecting to 'brand switching intentions'. Meanwhile, as the result of recognizing about effects of perceived values on the loyalty, it was appeared such like 'continued using intents' affected to'functional value', 'monetary value', and 'social value' first, and also 'monetary value', 'emotional value', and 'social value' affected to 'recommending intents to others'. On the other hand, it was shown such like only 'social value' affected influences to 'brand switching intents', and thus contrary results with the factor 'constant-using intents' were displayed. So, it seems that there are many applications to service provides who are worrying about marketing strategies for making consumer retains (constant-using) and new consumer's inductions (brand-switching intents). Finally, as a result of looking into intermediating roles of the use-diffusion factor in relations between conceived values and royalties at hypothesis 4, 'using' and 'using diversity' were displayed as affecting significant influences all together. Regarding to research result's implications, for expanding and promoting continued uses of the mobile instant messaging service by service providers: First, encouraging recognitions on the perceived value connected to users' service usage are necessary. Second, setting up user's use-diffusion strategies are required so as to enhance the loyalty after understanding a fact that use-diffusion patterns affecting to the service's loyalty are different. Finally, methods of raising customer loyalties and making constant relationships have to be grouped by analyzing on what are the customer value's factors that can satisfy users in competitive alterations.

Improving the Accuracy of Document Classification by Learning Heterogeneity (이질성 학습을 통한 문서 분류의 정확성 향상 기법)

  • Wong, William Xiu Shun;Hyun, Yoonjin;Kim, Namgyu
    • Journal of Intelligence and Information Systems
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    • v.24 no.3
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    • pp.21-44
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    • 2018
  • In recent years, the rapid development of internet technology and the popularization of smart devices have resulted in massive amounts of text data. Those text data were produced and distributed through various media platforms such as World Wide Web, Internet news feeds, microblog, and social media. However, this enormous amount of easily obtained information is lack of organization. Therefore, this problem has raised the interest of many researchers in order to manage this huge amount of information. Further, this problem also required professionals that are capable of classifying relevant information and hence text classification is introduced. Text classification is a challenging task in modern data analysis, which it needs to assign a text document into one or more predefined categories or classes. In text classification field, there are different kinds of techniques available such as K-Nearest Neighbor, Naïve Bayes Algorithm, Support Vector Machine, Decision Tree, and Artificial Neural Network. However, while dealing with huge amount of text data, model performance and accuracy becomes a challenge. According to the type of words used in the corpus and type of features created for classification, the performance of a text classification model can be varied. Most of the attempts are been made based on proposing a new algorithm or modifying an existing algorithm. This kind of research can be said already reached their certain limitations for further improvements. In this study, aside from proposing a new algorithm or modifying the algorithm, we focus on searching a way to modify the use of data. It is widely known that classifier performance is influenced by the quality of training data upon which this classifier is built. The real world datasets in most of the time contain noise, or in other words noisy data, these can actually affect the decision made by the classifiers built from these data. In this study, we consider that the data from different domains, which is heterogeneous data might have the characteristics of noise which can be utilized in the classification process. In order to build the classifier, machine learning algorithm is performed based on the assumption that the characteristics of training data and target data are the same or very similar to each other. However, in the case of unstructured data such as text, the features are determined according to the vocabularies included in the document. If the viewpoints of the learning data and target data are different, the features may be appearing different between these two data. In this study, we attempt to improve the classification accuracy by strengthening the robustness of the document classifier through artificially injecting the noise into the process of constructing the document classifier. With data coming from various kind of sources, these data are likely formatted differently. These cause difficulties for traditional machine learning algorithms because they are not developed to recognize different type of data representation at one time and to put them together in same generalization. Therefore, in order to utilize heterogeneous data in the learning process of document classifier, we apply semi-supervised learning in our study. However, unlabeled data might have the possibility to degrade the performance of the document classifier. Therefore, we further proposed a method called Rule Selection-Based Ensemble Semi-Supervised Learning Algorithm (RSESLA) to select only the documents that contributing to the accuracy improvement of the classifier. RSESLA creates multiple views by manipulating the features using different types of classification models and different types of heterogeneous data. The most confident classification rules will be selected and applied for the final decision making. In this paper, three different types of real-world data sources were used, which are news, twitter and blogs.

Issue tracking and voting rate prediction for 19th Korean president election candidates (댓글 분석을 통한 19대 한국 대선 후보 이슈 파악 및 득표율 예측)

  • Seo, Dae-Ho;Kim, Ji-Ho;Kim, Chang-Ki
    • Journal of Intelligence and Information Systems
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    • v.24 no.3
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    • pp.199-219
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    • 2018
  • With the everyday use of the Internet and the spread of various smart devices, users have been able to communicate in real time and the existing communication style has changed. Due to the change of the information subject by the Internet, data became more massive and caused the very large information called big data. These Big Data are seen as a new opportunity to understand social issues. In particular, text mining explores patterns using unstructured text data to find meaningful information. Since text data exists in various places such as newspaper, book, and web, the amount of data is very diverse and large, so it is suitable for understanding social reality. In recent years, there has been an increasing number of attempts to analyze texts from web such as SNS and blogs where the public can communicate freely. It is recognized as a useful method to grasp public opinion immediately so it can be used for political, social and cultural issue research. Text mining has received much attention in order to investigate the public's reputation for candidates, and to predict the voting rate instead of the polling. This is because many people question the credibility of the survey. Also, People tend to refuse or reveal their real intention when they are asked to respond to the poll. This study collected comments from the largest Internet portal site in Korea and conducted research on the 19th Korean presidential election in 2017. We collected 226,447 comments from April 29, 2017 to May 7, 2017, which includes the prohibition period of public opinion polls just prior to the presidential election day. We analyzed frequencies, associative emotional words, topic emotions, and candidate voting rates. By frequency analysis, we identified the words that are the most important issues per day. Particularly, according to the result of the presidential debate, it was seen that the candidate who became an issue was located at the top of the frequency analysis. By the analysis of associative emotional words, we were able to identify issues most relevant to each candidate. The topic emotion analysis was used to identify each candidate's topic and to express the emotions of the public on the topics. Finally, we estimated the voting rate by combining the volume of comments and sentiment score. By doing above, we explored the issues for each candidate and predicted the voting rate. The analysis showed that news comments is an effective tool for tracking the issue of presidential candidates and for predicting the voting rate. Particularly, this study showed issues per day and quantitative index for sentiment. Also it predicted voting rate for each candidate and precisely matched the ranking of the top five candidates. Each candidate will be able to objectively grasp public opinion and reflect it to the election strategy. Candidates can use positive issues more actively on election strategies, and try to correct negative issues. Particularly, candidates should be aware that they can get severe damage to their reputation if they face a moral problem. Voters can objectively look at issues and public opinion about each candidate and make more informed decisions when voting. If they refer to the results of this study before voting, they will be able to see the opinions of the public from the Big Data, and vote for a candidate with a more objective perspective. If the candidates have a campaign with reference to Big Data Analysis, the public will be more active on the web, recognizing that their wants are being reflected. The way of expressing their political views can be done in various web places. This can contribute to the act of political participation by the people.

The Analysis of the Successful Factors from User Side of MMORPG (사용자 측면에서의 MMORPG <월드 오브 워크래프트> 성공요인 분석)

  • Baek, Jaeyong;Kim, Kenneth Chi Ho
    • Cartoon and Animation Studies
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    • s.42
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    • pp.151-175
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    • 2016
  • The game industry has evolved from mobile games to PC online games after the smart-phone industry was opened up. In this environment, the game industry has rather been negatively developing its commercials means than the sufficient fundamental entertainment to the users. Especially, many games were released with better graphic qualities yet poor originality, continuing to be popular without enhancing the market itself. Moreover, the user's recognition level has improved. The users share their online gaming experience easily with the development of network environment. They receive the feedbacks on the quality of the game through the online channels and media by sharing them together. The high margin of the game industry will lead to the negative feedbacks of the users, effecting them to critique the content although the market looks good for now. The game industry's evolution has to be reviewed in the perspective of users, to look back at the successful cases of the past before the mobile era by analyzing and indicating the quality of the games and content's direction. This research is focused on the success factors of from the user's point of view, which has been widely claimed as a popular game franchise publicly before the mobile games had risen. WOW has been the most successful MMORPG game with its user record of 1.2 million till now. For these reasons, this study analyzes 's success factors from the user's point of view by configuring five expert groups, sequentially applying expert group survey, interview, Jobs-to-be-done and Fishbein Model as UX methodologies based on the business model to see through its long term rein in the industry. Consequently, The success factors from the user side of MMORPG provides an opportunity for the users to interact deeply with the game by (1) using well designed 'world view' over 10 years, (2) providing 'national policy' that is based on the locations of the users' culture and language, (3) providing 'expansions' with changes in time to give the digging elements to the users.

An Embedding /Extracting Method of Audio Watermark Information for High Quality Stereo Music (고품질 스테레오 음악을 위한 오디오 워터마크 정보 삽입/추출 기술)

  • Bae, Kyungyul
    • Journal of Intelligence and Information Systems
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    • v.24 no.2
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    • pp.21-35
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    • 2018
  • Since the introduction of MP3 players, CD recordings have gradually been vanishing, and the music consuming environment of music users is shifting to mobile devices. The introduction of smart devices has increased the utilization of music through music playback, mass storage, and search functions that are integrated into smartphones and tablets. At the time of initial MP3 player supply, the bitrate of the compressed music contents generally was 128 Kbps. However, as increasing of the demand for high quality music, sound quality of 384 Kbps appeared. Recently, music content of FLAC (Free License Audio Codec) format using lossless compression method is becoming popular. The download service of many music sites in Korea has classified by unlimited download with technical protection and limited download without technical protection. Digital Rights Management (DRM) technology is used as a technical protection measure for unlimited download, but it can only be used with authenticated devices that have DRM installed. Even if music purchased by the user, it cannot be used by other devices. On the contrary, in the case of music that is limited in quantity but not technically protected, there is no way to enforce anyone who distributes it, and in the case of high quality music such as FLAC, the loss is greater. In this paper, the author proposes an audio watermarking technology for copyright protection of high quality stereo music. Two kinds of information, "Copyright" and "Copy_free", are generated by using the turbo code. The two watermarks are composed of 9 bytes (72 bits). If turbo code is applied for error correction, the amount of information to be inserted as 222 bits increases. The 222-bit watermark was expanded to 1024 bits to be robust against additional errors and finally used as a watermark to insert into stereo music. Turbo code is a way to recover raw data if the damaged amount is less than 15% even if part of the code is damaged due to attack of watermarked content. It can be extended to 1024 bits or it can find 222 bits from some damaged contents by increasing the probability, the watermark itself has made it more resistant to attack. The proposed algorithm uses quantization in DCT so that watermark can be detected efficiently and SNR can be improved when stereo music is converted into mono. As a result, on average SNR exceeded 40dB, resulting in sound quality improvements of over 10dB over traditional quantization methods. This is a very significant result because it means relatively 10 times improvement in sound quality. In addition, the sample length required for extracting the watermark can be extracted sufficiently if the length is shorter than 1 second, and the watermark can be completely extracted from music samples of less than one second in all of the MP3 compression having a bit rate of 128 Kbps. The conventional quantization method can extract the watermark with a length of only 1/10 compared to the case where the sampling of the 10-second length largely fails to extract the watermark. In this study, since the length of the watermark embedded into music is 72 bits, it provides sufficient capacity to embed necessary information for music. It is enough bits to identify the music distributed all over the world. 272 can identify $4*10^{21}$, so it can be used as an identifier and it can be used for copyright protection of high quality music service. The proposed algorithm can be used not only for high quality audio but also for development of watermarking algorithm in multimedia such as UHD (Ultra High Definition) TV and high-resolution image. In addition, with the development of digital devices, users are demanding high quality music in the music industry, and artificial intelligence assistant is coming along with high quality music and streaming service. The results of this study can be used to protect the rights of copyright holders in these industries.

The Effect of Mobile Advertising Platform through Big Data Analytics: Focusing on Advertising, and Media Characteristics (빅데이터 분석을 통한 모바일 광고플랫폼의 광고효과 연구: 광고특성, 매체특성을 중심으로)

  • Bae, Seong Deok;Park, Do-Hyung
    • Journal of Intelligence and Information Systems
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    • v.24 no.2
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    • pp.37-57
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    • 2018
  • With the spread of smart phones, interest in mobile media is on the increase as useful media recently. Mobile media is assessed as having differentiated advantages from existing media in that not only can they provide consumers with desired information anytime and anywhere but also real-time interaction is possible in them. So far, studies on mobile advertising were mostly researches analyzing satisfaction with, and acceptance of, mobile advertising based on survey, researches focusing on the factors affecting acceptance of mobile advertising messages and researches verifying the effect of mobile advertising on brand recall, advertising attitude and brand attitude through experiments. Most of the domestic mobile advertising studies related to advertisement effect and advertisement attitude have been conducted through experiments and surveys. The advertising effectiveness measure of the mobile ad used the attitude of the advertisement, purchase intention, etc. To date, there have been few studies on the effects of mobile advertising on actual advertising data to prove the characteristics of the advertising platform and to prove the relationship between the factors influencing the advertising effect and the factors. In order to explore advertising effect of mobile advertising platform currently commercialized, this study defined advertising characteristics and media characteristics from the perspective of advertiser, advertising platform and publisher and analyzed the influence of each characteristic on advertising effect. As the advertisement characteristics, we classified advertisement format classified by bar type and floating type, and advertisement material classified by image and text. We defined advertisement characteristics of advertisement platform as Hedonic and Utilitarian media characteristics. As a dependent variable, we use CTR, which is the ratio of response (click) to ad exposure. The theoretical background and the analysis of the mobile advertising business, the hypothesis that the advertisement effect is different according to the advertisement specification, the advertisement material, In the ad standard, bar ads are classified as static framing, Floating ads can be categorized as dynamic framing, and the hypothetical definition of floating advertisements, which are high-profile dynamic framing ads, is highly responsive. In advertising, images with high salience are defined to have higher ad response than text. In the media characteristics classified as practical / hedonic type, it is defined that the hedonic type media has a more relaxed tendency than the practical media, and there is a high possibility of receiving various information because there is no clear target. In addition, image material and hedonic media are defined to be highly effective in the interaction between advertisement specification and advertisement material, advertisement specifications and media characteristics, and advertisement material and media characteristics. As the result of regression analysis on each characteristic, material standard, which is a characteristic of mobile advertisement, and media characteristics separated into 'Hedonic' and 'Utilitarian' had significant influence on advertisement effect and mutual interaction effect was also confirmed. In the mobile advertising standard, the advertising effect of the floating advertisement is higher than that of the bar advertisement, Floating ads were more effective than text ads for image ads. In addition, it was confirmed that the advertising effect is higher in the practical media than the hedonic media. The research was carried out with the big data collected from the mobile advertising platform, and it was possible to grasp the advertising effect of the measure index standard which is used in the practical work which could not be grasped in the previous research. In other words, the study was conducted using the CTR, which is a measure of the effectiveness of the advertisement used in the online advertisement and the mobile advertisement, which are not dependent on the attitude of the ad, the attitude of the brand, and the purchase intention. This study suggests that CTR is used as a dependent variable of advertising effect based on actual data of mobile ad platform accumulated over a long period of time. The results of this study is expected to contribute to establishment of optimum advertisement strategy such as creation of advertising materials and planning of media which suit advertised products at the time of mobile advertisement.

Survey of ICT Apply to Plastic Greenhouse, Rack·Pinion Adaption to Single Span and CFD Analysis (온실 ICT융복합 실태조사와 복숭아형 랙피니언천창 적용 단동온실 및 CFD 유동해석)

  • Cho, Kyu Jeong;Kim, Ki Young;Yang, Won Mo
    • Journal of Bio-Environment Control
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    • v.24 no.4
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    • pp.308-316
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    • 2015
  • This study was conducted to investigate the situation of ICT apply to plastic greenhouse, and the results be apply to design of new one. A CFD analysis were conducted to monitering the ventilation and energy saving of the single span greenhouse newly designed. The causes of delay to apply ICT to plastic greenhouse are the high cost for installation(24%), insufficiency of after services(19%), often disorder(16%), unskillful management of soft ware(15%), insufficient ICT efficiency(13%) and unsatisfying of income increase(12%). The parts of problem occurred in ICT plastic greenhouse are the structure, actuator, environmental control system and sensor(approximate 14%, respectively), remote control technique(13%), plant management technique(12%), energy saving technique(10%) and utilization of software(8%). In the condition of lateral window closed, the average wind speed changed to slow, but it was faster in the condition of leeward side window opened than in the condition of lee and winward side window opened. The air movement in the condition of lateral window closed occur by air moving fan not by out air. It is not affect the room temperature but effective the uniformity of room temperature. The average temperature of low height greenhouse was uniform than high height one. The average temperature in condition of 3rd curtain opened become same with outside temperature after 2 hours, but take more 5 hours in condition of 3rd curtain closed.

A Study on the Improvement for Medical Service Using Video Promotion Materials for PET/CT Scans (PET/CT 검사에서 동영상 홍보물을 통한 의료서비스 향상에 관한 연구)

  • Kim, Woo Hyun;Kim, Jung Seon;Ko, Hyun Soo;Sung, Ji Hye;Lee, Jeoung Eun
    • The Korean Journal of Nuclear Medicine Technology
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    • v.17 no.1
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    • pp.30-35
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    • 2013
  • Purpose: One of the current services, providing information to the patients and their guardians by using promotion materials induces positive responses and contributes to the improvement of the hospital reliability. Therefore, the objective of this study is to evaluate the effectiveness of audio visual materials, one of the means of promotion, as a way to give accurate medical information to resolve patient's curiosity about purpose and procedure of their examination and deplete complains about waiting which attributes negative effect to service quality assessment. Materials and Methods: 60 patients(mean age $53.97{\pm}12.24$, male : female = 26 : 34) who had $^{18}F-FDG PET/CT$ scan from July 2012 to August 2012 in Seoul Asan Medical Center were referred to the study. All of the patients having PET/CT scan were asked to watch an informative video material before the injection of radiopharmaceutical ($^{18}F-FDG$) and to fill in a questionnaire. Results: As a result of analyzing the contents of questionnaire, 52% of 60 patients had PET/CT scan for the first time and 72.4% of the patients read the PET/CT guidebook offered from their outpatient department or inpatient wards before their scan. After we searched the level of previous knowledge of the purpose and method of PET/CT scan, the patients answered 25.1% "know well", 34% "not sure", 40.9% "don't know" respectively. And 84.7% of the patients answered that watching the PET/CT guide video before the injection helps understanding what exam they were having and 15.3% of the patients did not. For the question asking ever the patients have experienced using our homepage or smart phone QR code to see the guide video before they visit out PET center, only 3.3% of them answered "yes". Lastly, the patients answered 60.1% "yes", 31.4% "so so" and 8.5% "no" respectively for the question asking whether watching the video makes the patients to fill the waiting time short. Conclusion: It is found that understanding of objective and method of the PET/CT scan and level of satisfaction was improved after the patients watched the guide video whether they had PET/CT scan before and read the PET/CT guidebook or not. Also, watching the video was effective for the reduction of perceptible waiting time. But while displaying the PET/CT guide video is useful for providing information about the scan and shortening the waiting time as one of the medical service, utilization of service was actually very poor because of the passive promotion and indifference of the patients about their examination. Therefore, from now on, it is necessary to construct the healthcare system which can be offered to more patients through the active promotion.

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Quality characteristics of domestic and imported commercial plain wheat flour (시판 우리밀과 수입밀 중력 밀가루의 품질 특성 비교)

  • Kwak, Han Sub;Kim, Mi Jeong;Kim, Hoon;Kim, Sang Sook
    • Korean Journal of Food Science and Technology
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    • v.49 no.3
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    • pp.304-310
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    • 2017
  • The aim of this study was to compare the physicochemical properties of domestic and imported commercial plain wheat flour and dough. Four types of domestic wheat flour (DW; DW1-4) were compared to four types of imported wheat flour (IW; IW1-4). DWs exhibited lower moisture content, lightness (L), and whiteness, and higher protein content, redness (a), and yellowness (b), than those exhibited by IWs. Solvent retention capacity of DWs and IWs was similar; however, DWs showed higher gluten performance index. Pasting properties, analyzed by rapid visco analyzer (RVA), were similar for DW1, DW2, and IWs; however, DW3 and DW4 showed different RVA patterns. Considering that DW3 and DW4 were organic wheat flour, possible incorporation of damaged kernel might increase amylase activities resulting in decreased peak viscosity. Dough resistance (108.4-159.9 g) and extensibility (11.8-16.7 mm) of IWs were higher than those of DWs (78.0-118.7 g, 8.7-12.5 mm, respectively).

Comparison study of dermal cell toxicity and zebrafish brain toxicity by humidifier sterilizer chemicals (PHMG, PGH, CMIT/MIT) (가습기 살균제 성분(PHMG, PGH, CMIT/MIT)의 사람 피부세포 독성 및 제브라피쉬 뇌신경 독성 비교 연구)

  • Cho, Kyung-Hyun;Kim, Jae-Ryong
    • Korean Journal of Environmental Biology
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    • v.38 no.2
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    • pp.271-277
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    • 2020
  • Toxicities to many organs caused by humidifier disinfectants have been reported. Recently, humidifier disinfectants have been reported to cause cardiovascular, embryonic, and hepatic toxicities. This study was designed to investigate the toxic mechanism of humidifier disinfectants and compare toxicity in a cellular model and a zebrafish animal model. Because brain toxicity and skin toxicity have been less studied than other organs, we evaluated toxicity in a human dermal cell line and zebrafish under various concentrations of humidifier disinfectants that included polyhexamethyleneguanidine phosphate (PHMG), oligo-[2-(2-ethoxy)-ethoxyethyl-guanidinium-chloride] (PGH) and methylchloroisothiazolinone/methylisothiazolinone (CMIT/MIT). A human dermal fibroblast cell line was treated with disinfectants (0, 2, 4, 6, 8, and 16 mg L-1) to compare their cytotoxicity. The fewest PHMG-treated cells survived (up to 33%), while 49% and 40% of the PGH- and CMIT/MIT-treated cells, respectively, survived. The quantification of oxidized species in the media revealed that the PHMG-treated cells had the highest MDA content of around 28 nM, while the PGH- and CMIT/MIT-treated cells had 13 and 21 nM MDA, respectively. As for brain toxicity, treatment of the zebrafish tank water with CMIT/MIT (final 40 mg L-1) for 30 min resulted in a 17-fold higher production of reactive oxygen species (ROS) than in the control. Treatment with PGH or PHMG (final 40 mg L-1) resulted in 15- and 11-fold higher production, respectively. The humidifier disinfectants (PHMG, PGH, and CMIT/MIT) showed severe dermal cell toxicity and brain toxicity. These toxicities may be relevant factors in understanding why some children have language disorders, motor delays, and developmental delays from exposure to humidifier disinfectants.