• Title/Summary/Keyword: specific field

Search Result 3,177, Processing Time 0.04 seconds

An investigation of members of the tribe Ceramieae (Ceramiaceae, Rhodophyta) occurring on both the Mediterranean and Atlantic shores of Morocco

  • Hassoun, Mustapha;Wynne, Michael J.;Moussa, Hanaa;Salhi, Ghizlane;Zbakh, Hanaa;Riadi, Hassane;Kazzaz, Mohamed
    • ALGAE
    • /
    • v.33 no.3
    • /
    • pp.243-267
    • /
    • 2018
  • A taxonomic study was recently carried out on species of the tribe Ceramieae (Ceramiaceae, Rhodophyta), following an evaluation of previously published records and on the basis of field and laboratory investigations. In Morocco, the tribe is represented by 5 genera: Ceramium (21 taxa at specific and infraspecific levels), Gayliella (3 species), and by one species each of Centroceras, Corallophila and Microcladia. Among these, there are five new records for Morocco: Centroceras gasparrinii, Ceramium botryocarpum, Ceramium cingulatum, Ceramium echionotum var. mediterraneum, and Gayliella taylorii. The report of C. echionotum var. mediterraneum from the Atlantic coast of Morocco is one of the rare records from outside the Mediterranean. Ceramium ciliatum var. robustum and Ceramium codii are recorded for the first time from the Atlantic coast of Morocco. Centroceras clavulatum is excluded from Moroccan flora having been misidentified for C. gasparrinii. This paper summarizes the taxonomic characters of these species with images and presents a key for their identification. This report is the first detailed record of the species of the tribe Ceramieae for Morocco. As a result, the total number of taxa at both specific and infraspecific levels accepted in the tribe Ceramieae for Morocco, under current taxonomy and nomenclature, is 27.

A Study on the Improvement of R&D commercialization policy system for Railroad Transportation (철도교통 분야 정책·제도적 R&D 실용화 촉진 방안 연구)

  • Kim, Dong-Hee;Rhu, Jae-Kyun;Yang, Keun-Yul
    • Journal of the Korea Safety Management & Science
    • /
    • v.17 no.3
    • /
    • pp.289-296
    • /
    • 2015
  • Recently, the Korean government has been making efforts to achieve 'creative economy' based on science and technology. As part of these efforts, it has been promoted specific policies for innovation and performance enhancement of national R&D projects. They contains commercialization of research outcomes, technology transfer, technology based startup and support small and medium-sized businesses. The railroad transportation industry is a representative in the field of SOC and has own characteristics different from other industry areas. Especially, industry and market of railroad transportation are directly related to planning and implementation of government SOC policies. So in order to promoting commercialization of railroad transportation projects, it is very important to ensure consistency between government policies and R&D projects. In this paper, we investigate barriers of successful commercialization with typical researchers in the area of railroad transportation, and suggest problems and improvements of policy-based commercialization by giving specific examples.

Frequency Analysis of Scientific Texts on the Hypoxia Using Bibliographic Data (논문 서지정보를 이용한 빈산소수괴 연구 분야의 연구용어 빈도분석)

  • Lee, GiSeop;Lee, JiYoung;Cho, HongYeon
    • Ocean and Polar Research
    • /
    • v.41 no.2
    • /
    • pp.107-120
    • /
    • 2019
  • The frequency analysis of scientific terms using bibliographic information is a simple concept, but as relevant data become more widespread, manual analysis of all data is practically impossible or only possible to a very limited extent. In addition, as the scale of oceanographic research has expanded to become much more comprehensive and widespread, the allocation of research resources on various topics has become an important issue. In this study, the frequency analysis of scientific terms was performed using text mining. The data used in the analysis is a general-purpose scholarship database, totaling 2,878 articles. Hypoxia, which is an important issue in the marine environment, was selected as a research field and the frequencies of related words were analyzed. The most frequently used words were 'Organic matter', 'Bottom water', and 'Dead zone' and specific areas showed high frequency. The results of this research can be used as a basis for the allocation of research resources to the frequency of use of related terms in specific fields when planning a large research project represented by single word.

A Case Study: Designeer Education Program and Application of Capstone Design - Focusing on Design Thinking Process of a Robot Vacuum Cleaner (디자이니어 양성 커리큘럼 및 캡스톤 디자인 응용 사례연구: 로봇청소기의 디자인적 사고 프로세스 사례를 중심으로)

  • Lim, Dokshin;Ahn, Junghyun
    • Journal of Engineering Education Research
    • /
    • v.22 no.2
    • /
    • pp.61-70
    • /
    • 2019
  • This paper deals with a 'Designeer' education program that has a specific objective of educating design to undergraduate students in mechanical engineering with the aim of enhancing their ability of collaboration with designers when they are going to work in the field after graduation. The entire curriculum of the Designeer education program is introduced first, the end of which two-semester Capstone Design Courses for senior students is offered to let them practice all the knowledge and skills in a project-based learning environment. Learning specific matters such as sketching & visual thinking, prototyping and user experience design is one thing and practicing those knowledge and skills into a Capstone Design project is another. At this point, design thinking process needs to be in place to give students a foresight of one-year journey and to ensure that they will produce a desirable, feasible and viable product at the end of the year when they define the right problem at the beginning. Their frustrations and discoveries while applying design thinking throughout the year is explained by taking an example of a Robot Vacuum Cleaner design project. Finally, we provide real examples of effective methods to practice divergent and convergent phases.

Family Business and Risk Management: Perspectives of SMEs Entrepreneurs in Indonesia

  • TAN, Jacob Donald;SUGIARTO, Sugiarto;BUDHIJONO, Fongnawati
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.8 no.5
    • /
    • pp.851-861
    • /
    • 2021
  • This study aims to explore the specific risks in family small-medium enterprises (SMEs) and explain how they manage these risks to sustain and expand. In Indonesia, family business composes around 95 percent of all businesses and contributes about 80 percent to the country's economy. SMEs contribute approximately 57.8 percent to the nation's gross domestic product. Risk management poses challenges to the family business's survival, as family members do not take actions on risk. The assessment of risk is difficult and family businesses lack the ability to determine risk management priorities, including risk management review processes to evaluate risk, thus leading to family business failures. Applying the case study approach, in-depth semi-structured interviews were conducted in seven family SMEs comprising fifteen informants. Additionally, a focus group discussion consisting of three experts is conducted to reaffirm the findings from the interviews, observations, and field notes. The research identified the specific risks and how the family owners strategize to safeguard against these risks such as cash flow deficiency, operations dysfunction, cultural frailty, disharmony, transgenerational entrepreneurship failure, political uncertainty, and unprofessionalism. Comprehending these risks and their strategic decisions elucidated in this research could enable the family owners and key non-family professionals to work hand-in-hand to thrive over the family business risks together. Further avenues of research regarding family business risk management are also suggested in this study.

Flexural analysis of transverse joints of prefabricated T-girder bridge superstructure

  • Kye, Seungkyung;Jung, Hyung-Jo;Park, Sun-Kyu
    • Structural Engineering and Mechanics
    • /
    • v.77 no.1
    • /
    • pp.89-102
    • /
    • 2021
  • Rapid construction of prefabricated bridges requires minimizing the field work of precast members and ensuring structural stability and constructability. In this study, we conducted experimental and analytical investigations of transverse joints of prefabricated T-girder bridge superstructures to verify the flexural performance and serviceability. In addition, we conducted parametric studies to identify the joint parameters. The results showed that both the segmented and continuous specimens satisfied the ultimate flexural strength criterion, and the segmented specimen exhibited unified behavior, with the flexural strength corresponding to that of the continuous specimen. The segmented specimens exhibited elastic behavior under service load conditions, and the maximum crack width satisfied the acceptance criteria. The reliability of the finite element model of the joint was verified, and parametric analysis of the convexity of the joint section and the compressive strength of the filler concrete showed that the minimum deflection and crack width occurred at a specific angle. As the strength of the filler concrete increased, the deflection and crack width decreased. However, we confirmed that the reduction in the crack width was hardly observed above a specific strength. Therefore, a design suitable for prefabricated bridges and accelerated construction can be achieved by improving the joint specifications based on the required criteria.

Geostatistical algorithm for evaluation of primary and secondary roughness

  • Nasab, Hojat;Karimi-Nasab, Saeed;Jalalifar, Hossein
    • Geomechanics and Engineering
    • /
    • v.24 no.4
    • /
    • pp.359-370
    • /
    • 2021
  • Joint roughness is combination of primary and secondary roughness. Ordinarily primary roughness is a geostatistical part of a joint surface that has a periodic nature but secondary roughness or unevenness is a statistical part of that which have a random nature. Using roughness generating algorithms is a useful method for evaluation of joint roughness. In this paper after determining geostatistical parameters of the joint profile, were presented two roughness generating algorithms using Mount-Carlo method for evaluation of primary (GJRGAP) and secondary (GJRGAS) roughness. These based on geostatistical parameters (range and sill) and statistical parameters (standard deviation of asperities height, SDH, and standard deviation of asperities angle, SDA) for generation two-dimensional joint roughness profiles. In this study different geostatistical regions were defined depending on the range and SDH. As SDH increases, the height of the generated asperities increases and asperities become sharper and at a specific range (a specific curve) relation between SDH and SDA is linear. As the range in GJRGAP becomes larger (the base of the asperities) the shape of asperities becomes flatter. The results illustrate that joint profiles have larger SDA with increase of SDH and decrease of range. Consequencely increase of SDA leads to joint roughness parameters such Z2, Z3 and RP increases. The results showed that secondary roughness or unevenness has a great influence on roughness values. In general, it can be concluded that the shape and size of asperities are appropriate parameters to approach the field scale from the laboratory scale.

Factors Influencing New Media Exposure of Political News by Youths in Isan Society

  • Jitsaeng, Khanittha;Chaikhambung, Juthatip
    • Journal of Information Science Theory and Practice
    • /
    • v.10 no.2
    • /
    • pp.86-101
    • /
    • 2022
  • This research aimed at studying the factors that influence new media exposure of political news by youths in Isan society in Thailand. The target group comprised 1,200 individuals, obtained from multi-stage sampling from undergraduate students in Isan's autonomous universities, governmental universities, and private institutions. The data collection tool was a questionnaire, the content of which was validated by experts. The reliability of the tool was tested by the formula for Cronbach's alpha coefficient, which yielded a reliability of 0.83. Multiple regression analysis was applied to analyze the data. The results, regarding factors influencing the channels for political news exposure, showed that channels for political news exposure were mostly influenced by inner drives, followed by importance in political news exposure, influence from social networks, and specific characteristics of the Internet. This could explain the variation of channels for political news exposure at 46.5%. In terms of factors influencing political news selection, it was found that political news selection was influenced mostly from social networks, followed by inner drives, benefits from political news exposure, specific characteristics of the Internet, and the field of study. The variation of the political news selection could be explained at 44.6%. These results elaborate on the current situation in Thailand, especially in Isan region, where youths in higher education are playing an increasing role in demonstrating their political stance through various political activities.

A Study on Vibration Characteristics and Machining Quality in Thin-wall Milling Process of Titanium Alloy (티타늄 합금의 얇은 벽 밀링가공에서 가공방법에 따른 진동특성 및 가공품질에 관한 연구)

  • Kim, Jong-Min;Koo, Joon-Young;Jun, Cha-Soo
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.21 no.6
    • /
    • pp.81-88
    • /
    • 2022
  • Titanium alloy (Ti-6Al-4V) has excellent mechanical properties and high specific strength; therefore, it is widely used in aerospace, automobile, defense, engine parts, and bio fields. Particularly in the aerospace field, as it has a low specific gravity and rigidity, it is used for the purpose of increasing energy efficiency through weight reduction of parts, and most have a thin-walled structure. However, it is extremely difficult to machine thin-walled shapes owing to vibration and deformation. In the case of thin-walled structures, the cutting forces and vibrations rapidly increase depending on the cutting conditions, significantly affecting the surface integrity and tool life. In this study, machining experiments on thin-wall milling of a titanium alloy (Ti-6Al-4V) were conducted for each experimental condition with different axial depths of cut, radial depth of cut, and machining sequence. The machining characteristics were analyzed, and an effective machining method was derived by a comprehensive analysis of the machined surface conditions and cutting signals.

Implementation and test results of on-channel repeater for ATSC 3.0 systems

  • Ahn, Sungjun;Kwon, Sunhyoung;Kwon, Hae-Chan;Kim, Youngsu;Lee, Jaekwon;Shin, Yoo-Sang;Park, Sung-Ik
    • ETRI Journal
    • /
    • v.44 no.5
    • /
    • pp.715-732
    • /
    • 2022
  • Despite the successful launch of Advanced Television Systems Committee (ATSC) 3.0 broadcasting worldwide, broadcasters are facing obstacles in constructing void-less large-scale single-frequency networks (SFNs). The bottleneck is the absence of decent on-channel repeater (OCR) solutions necessary for SFNs. In the real world, OCRs suffer from the maleficent feedback interference (FI) problem, which overwhelms the desired input signal. Moreover, the undesired multipaths between studio-linked transmitters and the OCR deteriorate the forward signals' quality as well. These problems crucially restrict the feasibility of conventional OCR systems, arousing the strong need for cost-worthy advanced OCR solutions. This paper presents an ATSC 3.0-specific solution of advanced OCR that solves the FI problem and refines the input signal. To this end, the FI canceler and channel equalizer functionalities are carefully implemented into the OCR system. The presented OCR system is designed to be fully compliant with the ATSC 3.0 specifications and performs a fast and efficient signal processing by exploiting the specific frame structure. The real product of ATSC 3.0 OCR is fabricated as well, and its feasibility is verified via field and laboratory experiments. The implemented solution is installed at a commercial on-air site and shown to provide substantial coverage gain in practice.