• Title/Summary/Keyword: Big Four

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Cyclic Shift Based Tone Reservation PAPR Reduction Scheme with Embedding Side Information for FBMC-OQAM Systems

  • Shi, Yongpeng;Xia, Yujie;Gao, Ya;Cui, Jianhua
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.8
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    • pp.2879-2899
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    • 2021
  • The tone reservation (TR) scheme is an attractive method to reduce peak-to-average power ratio (PAPR) in the filter bank multicarrier with offset quadrature amplitude modulation (FBMC-OQAM) systems. However, the high PAPR of FBMC signal will severely degrades system performance. To address this issue, a cyclic shift based TR (CS-TR) scheme with embedding side information (SI) is proposed to reduce the PAPR of FBMC signals. At the transmitter, four candidate signals are first generated based on cyclic shift of the output of inverse discrete Fourier transform (IDFT), and the SI of the selected signal with minimum peak power among the four candidate signals is embedded in sparse symbols with quadrature phase-shift keying constellation. Then, the TR weighted by optimal scaling factor is employed to further reduce PAPR of the selected signal. At the receiver, a reliable SI detector is presented by determining the phase rotation of SI embedding symbols, and the transmitted data blocks can be correctly demodulated according to the detected SI. Simulation results show that the proposed scheme significantly outperforms the existing TR schemes in both PAPR reduction and bit error rate (BER) performances. In addition, the proposed scheme with detected SI can achieve the same BER performance compared to the one with perfect SI.

Assessment of Needs for Housing Improvement of Children Group Homes in Cheongju through Interviews with Group Home Directors and Staffs (실무자 인터뷰를 통한 청주시 아동 그룹홈의 주거 개선 요구 조사)

  • Lee, Sang Woo;Yi, Minseo;You, Zikang;Lee, Hyun-Jeong
    • Journal of Urban Science
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    • v.9 no.2
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    • pp.1-11
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    • 2020
  • The purpose of this study was to assess needs for housing improvement of children group homes in Cheongju-si through interviews with the group home directors and staffs. From April 6, 2018, to April 25, 2018, a series of face-to-face interviews with four directors and three staffs working in four children group homes was conducted. The results were analyzed using thematic analysis technique. Highlights of major findings and implications were as follow: (1) Bedroom: Needs for independent bedrooms and desks for each child were dominant. (2) Common activity space: Interviewees showed somewhat different opinions on common activity spaces according to group home types and/or between directors and staffs. (3) Between "a big and good-quality house" and "a house in good location", interviewees were found to prefer "a big and good-quality house" in order for children to have enough space to run and play. (4) Interviewees insisted that to provide proper group home services and protection similar to a real family, current policy to accommodate up to eight children in one group home should be improved.

Does Audit Matter in Earnings Quality of Indonesia Banks?

  • MULIATI, Muliati;MAYAPADA, Arung Gihna;PARWATI, Ni Made Suwitri;RIDWAN, Ridwan;SALMITA, Dewi
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.2
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    • pp.143-150
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    • 2021
  • This study investigates and analyzes the difference in Indonesian banks' earnings quality in the pre-audit and post-audit period. This study also investigates the difference in audit quality done by public accounting firms. This study employs time series data taken from the unaudited and audited financial statements of banks listed on the Indonesia Stock Exchange in 2012-2016. Sample selection is made by using a purposive sampling method. The population of this study is 43 banks, and after checking the data for validity and reliability, the final sample size was 26 banks. Audit quality is operationalized with the size of the auditor. Earnings quality is proxied by accruals calculated using the Beaver and Engel (1996) model. The data analysis method used in this study is the paired-sample t-test and chow test. This study shows that there is no difference in earnings quality in the pre-audit and post-audit period. This study also reveals no difference in audit quality between the big four and non-big four auditors. These findings mean that independent auditors do not play a useful role in increasing the reliability of accounting information presented by management to stakeholders. Besides, this study's results do not verify the agency theory regarding auditors' role to minimize opportunistic management behavior in preparing financial statements.

Effects on the Use of Two Textbooks for Four Types of Classes in a South Korean University

  • Ramos, Ian Done D.
    • International Journal of Advanced Culture Technology
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    • v.1 no.2
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    • pp.24-32
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    • 2013
  • This paper determined students' ranks of difficulty on the use of materials in terms of 1) understanding the layout of the learning materials, 2) reading comprehension of the learning materials, and 3) realization on relevance to needs of the learning materials. It also determined students' 4) rank and frequency of attitude on the materials. With the data gathered through 128 survey questionnaires, 7 focused group discussions, and 10 interviews, the results were found out that there was an inappropriate assessment procedure set by this particular university. The researcher concludes that: 1) design of four types of classes by just using the two textbooks with their respective workbooks is grammar-based with limited conversation activities; 2) placement for these students in one big class size was implemented without considering their common interest and motivation and language levels; and, 3) qualification of teachers teaching these EFL students did not support students' real needs and the language program itself. Content professors who were made to teach may have the ability to input learning, but their teaching styles may differ from the ones who are real English teachers. This paper then recommends that teachers and school administration should have an appropriate placement exam before students attend the class, especially in a big class size. There could only be a few problems among students in one big class size when students' level of competence is proportioned. With this, topics and conversation activities can even be more flexible with the maneuver of art of questioning, various dimensions of thinking, strategic competence, learning attitude or behavior, etc. to ensure sustenance of communicative mode and level of interest and motivation in the classroom. Grammar-based instruction can only be taught when a need arises. Thus, the course description of each class will be able to transact the objectives ready for developing students' communication competence. Moreover, proper measurement can be utilized to validly assess the amount of students' learning and the progress of language curriculum design in terms of materials selection and teaching approach.

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Comparative Analysis in Perception on Men's Fashion Using Big Data : Focused on Influence of COVID-19 (빅 데이터를 활용한 코로나19 이전과 이후의 남성 패션에 대한 인식 비교)

  • Kim, Do-Hyeon;Kim, Jeong-Mee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.24 no.3
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    • pp.1-15
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    • 2022
  • The purpose of this study is to compare and analyze the perception of men's fashion before and after the COVID-19 pandemic. TEXTOM allowed the collection of Big Data based on the term 'men's fashion'. As for the data collection periods, Jan. 1, 2018 to Dec. 31, 2019 was set as the pre-COVID-19 era, while Jan. 1, 2020 to Dec. 31, 2021 was set as the post-COVID-19 era. The top 50 words in terms of appearance frequency were extracted from the data. The extracted words were processed using network centrality analysis and CONCOR analysis using Ucinet 6. Research findings were as follows. 1) In the pre-COVID-19 era, the appearance frequency of 'men' was the highest, followed by 'fashion', 'men's fashion', 'brand', 'daily look', 'suit', and 'department store'. These words came up with a high TF-IDF values. Network centrality analysis discovered that 'men', 'fashion', 'men's fashion', 'brand', and 'suit' had a high level of connectivity with other words. CONCOR analysis showed four significant groups: 'fashion item and styles', 'fashion show', 'purchase', and 'collection'. 2) In the post-COVID-19 era, the appearance frequency of 'men' was the highest, followed by 'fashion', 'brand', 'men's fashion', 'discount', 'women', and 'luxury'. These words also displayed high TF-IDF values. Network centrality analysis found that 'fashion', 'men', 'brand', 'men's fashion', and 'discount' had a high level of connectivity with other words. CONCOR analysis showed four significant groups: 'fashion item and style', 'fashion show', 'purchase', and 'situation'. 3) Before the outbreak of the pandemic, men were interested in suits to wear to the office, daily look, and fashion shows in Milan and Paris. They often purchased menswear in multi-brand and open stores. However, they were more interested in sneakers, casual styles, and online fashion shows as social distancing and working from home became common. Most purchased menswear through online platforms.

A Study on the Selection of Core Services for Geo-Spatial Big Data (공간 빅데이터 핵심서비스 선정에 관한 연구)

  • Lee, Myeong Ho;Park, Joon Min;Shin, Dong bin;Ahn, Jong Wook
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.5
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    • pp.385-396
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    • 2015
  • The purpose of this study are in selecting a core service and drawing an analysis functions and service sector, based on contents of geo-spatial big data. For the study, the demand survey in the methodology has to be done by reviewing of preceding geo-spatial big data service. The survey has conducted by targeting on those experts in Industry-Academy-Research cooperation. From the survey, we could draw out requirements for the analysis function and the geo-spatial big data service sector. Also, order of priorities in service of four fields(Society, Environment, Economy, Humanities) has been utilized by a QFD(Quality Function Deployment). With the data, the first two priorities and required sectors for each field were selected for the analysis functions. From the result, we could suggest the core service model(plan), and also expect developments following each sectoral core service in the future.

Trends of South Korea's Informatization and Libraries' Role Based on Newspaper Big Data (신문 빅데이터를 바탕으로 본 국내 정보화의 경향과 도서관의 역할)

  • Na, Kyoungsik;Lee, Jisu
    • The Journal of the Korea Contents Association
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    • v.18 no.9
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    • pp.14-33
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    • 2018
  • The purpose of this study to analyze the informatization trends in Korea through objective newspaper data for the period from 1998 to 2017 for informatization and library in four newspapers including KyoungHyang Newspaper, Kookmin Ilbo, Hankyoreh and Hankookilbo. Based on the analysis results of metadata and related words using BIGKinds, a news big data system, this study presented analysis of simple frequency, classification and classification of the keywords 'information', 'informatization' and 'library'. Based on the results, we compared and analyzed the tendency of informatization in the media through comparison with the 'Information White Paper' which is the publication of government agencies and with research about the research topic of 4 academic journals in the Library and Information Science field. This study tried to interpret the trends of informatization based on the media and it is meaningful that we analyzed the big data of newspaper article which is the long term and time series data. Based on the results of the study, implications of the growth and development of libraries with domestic informatization were suggested. It is expected that we will be able to create a basic framework for developing library informatization policy through the further studies.

Study on Big Data Utilization Plans of Medical Institutions (의료기관의 빅데이터 활용방안에 대한 연구)

  • Kim, Sung-Soo
    • Journal of Digital Convergence
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    • v.12 no.2
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    • pp.397-407
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    • 2014
  • Due to rapid development of medical information, a huge amount of information is being accumulated. Desires to conduct clinical researches by using this information are increasing, and medical institutions are encountering problems of aging society and drastic increase of medical expenses. Utilization of Big Data as an alternative is now being emphasized. The purpose of this study is to examine informatization of medical institutions and suggest political implications for Big Data utilization plans. Data was collected through literature searches and interviews with medical information professionals of medical institutions, from September to November, 2013, for four months. As a result of the study, it could be found that the hospital information system is improving from patient management and administration to researches and information strategies. Thus, national supports for medical expense reduction as well as fostering professional manpower should be provided, considering establishment of the system for utilization of Big Data and efficient application of unstructured data.

Interaction of the Lysophospholipase PNPLA7 with Lipid Droplets through the Catalytic Region

  • Chang, Pingan;Sun, Tengteng;Heier, Christoph;Gao, Hao;Xu, Hongmei;Huang, Feifei
    • Molecules and Cells
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    • v.43 no.3
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    • pp.286-297
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    • 2020
  • Mammalian patatin-like phospholipase domain containing proteins (PNPLAs) play critical roles in triglyceride hydrolysis, phospholipids metabolism, and lipid droplet (LD) homeostasis. PNPLA7 is a lysophosphatidylcholine hydrolase anchored on the endoplasmic reticulum which associates with LDs through its catalytic region (PNPLA7-C) in response to increased cyclic nucleotide levels. However, the interaction of PNPLA7 with LDs through its catalytic region is unknown. Herein, we demonstrate that PNPLA7-C localizes to the mature LDs ex vivo and also colocalizes with pre-existing LDs. Localization of PNPLA7-C with LDs induces LDs clustering via non-enzymatic intermolecular associations, while PNPLA7 alone does not induce LD clustering. Residues 742-1016 contains four putative transmembrane domains which act as a LD targeting motif and are required for the localization of PNPLA7-C to LDs. Furthermore, the N-terminal flanking region of the LD targeting motif, residues 681-741, contributes to the LD targeting, whereas the C-terminal flanking region (1169-1326) has an anti-LD targeting effect. Interestingly, the LD targeting motif does not exhibit lysophosphatidylcholine hydrolase activity even though it associates with LDs phospholipid membranes. These findings characterize the specific functional domains of PNPLA7 mediating subcellular positioning and interactions with LDs, as wells as providing critical insights into the structure of this evolutionarily conserved phospholipid-metabolizing enzyme family.

A Study on Big Data Maturity Assessment Framework for Corporate Data Strategy and Investment (기업 데이터 전략과 투자를 위한 빅데이터 성숙도 평가 프레임워크 실증 연구)

  • Kim, Okki;Park, Jung;Cho, Wan-Sup
    • The Journal of Bigdata
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    • v.6 no.1
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    • pp.13-22
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    • 2021
  • The purpose of this study is to develop and demonstrate a framework for evaluating the maturity of big data for effective data strategy establishment and efficient investment of companies. By supplementing the shortcomings of the evaluation developed so far, a framework was developed to evaluate the maturity of a company's big data in an integrated process. As a result, four evaluation areas of 'Vision and Strategy', 'Management', 'Analysis' and 'Utilization', assessment items for each area, detailed content, and criteria for each stage were derived. This was verified through a survey of entrepreneurs, and the maturity level of big data of domestic companies was confirmed. As a future research direction, it is proposed to develop detailed assessment factors according to the characteristics of each industry, to develop a data utilization framework according to the assessment results, and to improve validity and reliability through adjustment of verification targets.