• IEIE Transactions on Smart Processing and Computing
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• 제5권2호
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• pp.100-106
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• 2016

Spectrum sensing is an integral part of cognitive radio, which seeks to address the perceived spectrum scarcity that is caused by inefficient utilization of the available spectrum. In this paper, a spectrum sensing system using energy detection for analog TV and FM broadcast transmitters as well as modified Integrated Services Digital Broadcasting Terrestrial (ISDB-T) signals is implemented on a software-defined radio platform using GNU' Not Unix (GNU) radio and the N200 Universal Software Radio Peripheral (USRP). Real-time implementation and experimental tests were conducted in Metro Cebu, a highly urbanized area in the southern part of the Philippines. Extensive tests and measurements were necessary to determine spectrum availability, particularly in the TV band. This is in support of the Philippine government' efforts to provide internet connectivity to rural areas. Experimental results have so far met IEEE 802.22 requirements for energy detection spectrum sensing. The designed system detected signals at -114 dBm within a sensing time of 100 ms. Furthermore, the required $P_d({\geq}90)$ and $P_{fa}({\leq}10)$ of the standard were also achieved with different thresholds for various signal sources representing primary users.

• KSBB Journal
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• 제28권2호
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• pp.86-91
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• 2013

To date, various strategies have been studied to increase specific productivity in Chinese hamster ovary (CHO) cell cultures. Also, albumin-fusion platform is being applied to other important bioactive peptides with short half-lives. Here, we investigated the effects of silkworm gland hydrolysate (SGH) on the production of albumin-erythropoietin (Alb-EPO) in transgenic CHO cells. The viable cell density of CHO cells was increased by 13% in the medium containing 1 mg/mL SGH higher than in the control medium without SGH. In addition, the production of Alb-EPO was also 1.26- fold enhanced by reducing the early apoptosis of CHO cells. In conclusion, SGH could be used as a useful supplement for the enhancement of recombinant protein production.

• Ocean Systems Engineering
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• 제7권2호
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• pp.107-120
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• 2017

Spud-can is used for fixing jack-up rig on seabed. It needs to be inserted up to the required depth during the installation process to secure enough soil reaction and prevent overturning accidents. On the other hand, it should be extracted from seabed soils as fast as possible during the extraction process to minimize the corresponding operational cost. To achieve such goals, spud-can may be equipped with water-jetting system including monitoring and control. To develop such a smart spud-can, a reliable numerical simulation tool is essential and it has also to be validated against physical model tests. In this regard, authors developed a numerical simulation tool by using a commercial program ANSYS with extended Drucker-Prager (EDP) formula. Authors also conducted small-scale (1/100) physical model tests for verification and calibration purpose. By using the numerical model, a systematic parametric study is conducted both for sand and K(kaolin)-clay with varying important soil parameters and the best estimated soil properties of the physical test are deduced. Then, by using the selected soil properties, the numerical and experimental results for a sand/K-clay multi-layer case are cross-checked to show reasonably good agreement. The validated numerical model will be useful in the next-stage study which includes controllable water-jetting.

• Corrosion Science and Technology
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• 제16권2호
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• pp.76-84
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• 2017

In the construction of subsea oil and gas developments, it is increasingly common that subsea oil and gas equipment will be installed in subsea well before final hookup and production. Installation of wellheads, subsea hardware, pipelines, and surface facilities (platforms, FPSO, FLNG, connected terminals, or gas plants) are increasingly driven by independent cost and vessel availability schedules; this gives rise to requirements that the subsea facilities must be stored in the seabed for a specific time. In addition, schedule delays, particularly in the installation or startup of the connected platform, FPSO, FLNG, or onshore plant may cause unexpected extensions of the intended storage period. Currently, there are two methods commonly used for storage subsea facilities in the seabed: dry parking and wet parking. Each method has its own risks, challenges, and implications for the facility life and its integrity. The corrosion management and preservation method selection is a crucial factor to be considered in choosing the appropriate storage method and achieving a successful seabed storage. An overview of those factors is presented, along with a discussion on the internal corrosion threats and assessments.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2015년도 춘계학술발표대회
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• pp.10-13
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• 2015

Google App Engine(GAE)은 플랫폼 서비스 형태(Platform as a Service, PaaS)의 클라우드 인프라이며 GAE를 기반으로 웹어플리케이션을 제작할 수 있도록 다양한 개발 도구를 제공해 준다. 본 논문에서는 Python 및 Go를 이용하여 GAE 상에서 구현한 클라우드 기반의 web application들의 성능을 비교하고자 한다. 각 web application의 주요 기능은 회원가입, 로그인, 채팅 등으로 구성되어 있고 특히, 회원목록이나 채팅 데이터를 처리하기 위하여 GAE에서 제공하는 Google Datastore를 사용하였다. 성능비교를 위하여 Python2.5, Python 2.7 및 Go를 사용하여 통일한 기능의 web application을 구현하였으며 각각의 메뉴에 대하여 서버 로직의 실행과 장고 (Django) 스타일의 HTML 템플릿을 렌더링하는데 걸리는 시간을 구하고 이를 비교 분석하였다.

• Advances in aircraft and spacecraft science
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• 제4권3호
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• pp.317-334
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• 2017

With rapid growth in the complexity of large scale engineering systems, the application of multidisciplinary analysis and design optimization (MDO) in the engineering design process has garnered much attention. MDO addresses the challenge of integrating several different disciplines into the design process. Primary challenges of MDO include computational expense and poor scalability. The introduction of a distributed, collaborative computational environment results in better utilization of available computational resources, reducing the time to solution, and enhancing scalability. SORCER, a Java-based network-centric computing platform, enables analyses and design studies in a distributed collaborative computing environment. Two different optimization algorithms widely used in multidisciplinary engineering design-VTDIRECT95 and QNSTOP-are implemented on a SORCER grid. VTDIRECT95, a Fortran 95 implementation of D. R. Jones' algorithm DIRECT, is a highly parallelizable derivative-free deterministic global optimization algorithm. QNSTOP is a parallel quasi-Newton algorithm for stochastic optimization problems. The purpose of integrating VTDIRECT95 and QNSTOP into the SORCER framework is to provide load balancing among computational resources, resulting in a dynamically scalable process. Further, the federated computing paradigm implemented by SORCER manages distributed services in real time, thereby significantly speeding up the design process. Part 1 covers SORCER and the algorithms, Part 2 presents results for aircraft panel design with curvilinear stiffeners.

• Advances in robotics research
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• 제2권3호
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• pp.183-199
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• 2018

This paper presents the development of a 3D printed humanoid robotic hands of SignBot, which can perform Malaysian Sign Language (MSL). The study is considered as the first attempt to ease the means of communication between the general community and the hearing-impaired individuals in Malaysia. The signed motions performed by the developed robot in this work can be done by two hands. The designed system, unlike previously conducted work, includes a speech recognition system that can feasibly integrate with the controlling platform of the robot. Furthermore, the design of the system takes into account the grammar of the MSL which differs from that of Malay spoken language. This reduces the redundancy and makes the design more efficient and effective. The robot hands are built with detailed finger joints. Micro servo motors, controlled by Arduino Mega, are also loaded to actuate the relevant joints of selected alphabetical and numerical signs as well as phrases for emergency contexts from MSL. A database for the selected signs is developed wherein the sequential movements of the servo motor arrays are stored. The results showed that the system performed well as the selected signs can be understood by hearing-impaired individuals.

• Child Health Nursing Research
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• 제27권1호
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• pp.13-23
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• 2021

Purpose: This study aimed to develop a mobile-based self-management health alarm (MSHA) program for modifying obese children's lifestyle based on the information-motivation-behavioral skills (IMB) model and to test its feasibility. Methods: A methodological study for the development of the MSHA program and pilot study with a one-group pretest-posttest design for feasibility testing was conducted. The MSHA program was designed to provide obesity-related information (I), monitor daily diet and exercise, provide motivational text messages (M), and enhance healthy diet and exercise skills (B) via a mobile-based web platform. In the feasibility test, six obese children participated in the 4-week program, and the number of days per week that they achieved their goals and differences in metabolic components were assessed. Data were analyzed using descriptive statistics and the Wilcoxon signed-rank test. Results: Participants successfully achieved their diet and exercise goals≥5 days per week. Body mass index (z=-1.99, p=.046), waist circumference (z=-2.20, p=.028), and triglyceride levels (z=-2.21, p=.027) significantly decreased. Conclusion: The MSHA program showed positive effects on health behaviors and metabolic syndrome risk. The program may be effective in improving metabolic syndrome in obese children by promoting self-health management behaviors.

• 지역사회간호학회지
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• 제32권1호
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• pp.116-129
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• 2021

Purpose: This study aimed to investigate the maternal health effects of internet-based education interventions on parturients during the postpartum period through a systematic review of randomized controlled trials. Methods: An electronic literature search of the Cochrane Library, CINAHL, EMBASE, Eric, PsycINFO, PubMed, RISS, and KISS databases was performed, using the combination of keywords such as 'parenthood education', '*natal education', '*birth intervention', 'internet-based intervention', 'randomized controlled trial'. The inclusion criteria were peer-reviewed papers in English regarding randomized controlled trials of internet-based postnatal education interventions. Educational interventions were delivered through any web, mobile, eHealth, mHealth, virtual reality, short message service, or social networking service platform. Quality appraisal was performed using the Risk of Bias 2 (RoB 2) for randomized controlled trials. Nine articles were yielded, and the intervention effects were analyzed. Results: Internet-based education interventions during the postpartum period affect maternal self-efficacy, postpartum depression, and successive breastfeeding; however, they do not affect maternal satisfaction and parenting confidence. Conclusion: This study demonstrated that internet-based education interventions affect maternal health status in terms of psychological, emotional, and physical wellness. Therefore, maternal health care professionals can utilize remote education using the internet or mobile-based interventions during the postpartum period.

• 한국인공지능학회지
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• 제8권2호
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• pp.11-16
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• 2020

Among the innovative companies leading the era of the 4th industrial revolution, the world's largest Internet company is Google. Google has grown by providing convenient services such as Internet search, Android smartphone operating system, and video. Now, Google is leading the global IT industry by continuing to develop in various new business fields based on open service platforms, artificial intelligence, and big data. In this study, an exploratory discussion was conducted on Google's success factors and future directions. The purpose of the research is to understand the development process of the IT field from the successfactors of Google and to analyze the development direction of the future IT industry. Google's success factors were its open platform policy and successful acquisitions of external companies. In fact, most of the services Google offers come from companies that have acquired and acquired them. In addition, there was a corporate culture that values and supportsthe spirit of challenge and autonomy of members who are not afraid of failure. Based on this study's review of Google's direction analysis, the follow-up study will infer the direction of the IT industry in depth and look at the future technologies that IT majors need to prepare.