• Journal of Communications and Networks
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• 제4권4호
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• pp.302-313
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• 2002

In order to facilitate and to meet the ever increasing demands for the wireless communication in the next decade and also to satisfy the high data rates for the new services, the future development of 3G (IMT2000) and systems beyond 3G (B3G) are foreseen. This article presents the need for these developments and motivations for systems beyond 3G taking into account both strategic and technological challenges to be faced. Moreover, the concepts and potential technologies involved including multiple airinterfaces, efficient spectrum allocation and utilisation for the success of systems B3G are briefly reviewed.

• 한국시스템다이내믹스연구
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• 제9권1호
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• pp.199-218
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• 2008

Empirical studies have shown that government and human service nonprofit organizations have maintained active partnerships to deliver human services for the past several decades. However, the previous researches on resource dependent government-nonprofit service delivery have revealed serious methodological limitations to adequately demonstrate the dynamic relationship between both sectors over time. Since the dynamics underlying the government-nonprofit service delivery is a complex process, in which multiple factors dynamically interact over time, the assumptions of system dynamics can help improve these methodological drawbacks. This study aims to explore methodological issues and weaknesses observed in empirical studies on resource dependent government-nonprofit service delivery in the United States, and further attempts to provide insights on future research toward a dynamic approach, bringing the assumptions of system dynamics to the challenges of the previous researches.

• Journal of Multimedia Information System
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• 제8권1호
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• pp.23-30
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• 2021

Palmprint has become a popular biometric modality; however, palmprint recognition has not been conducted in video media. Video palmprint recognition (VPR) has some advantages that are absent in image palmprint recognition. In VPR, the registration and recognition can be automatically implemented without users' manual manipulation. A good-quality image can be selected from the video frames or generated from the fusion of multiple video frames. VPR in contactless mode overcomes several problems caused by contact mode; however, contactless mode, especially mobile mode, encounters with several revere challenges. Double-line-single-point (DLSP) assisted placement technique can overcome the challenges as well as effectively reduce the localization error and computation complexity. This paper modifies DLSP technique to reduce the invalid area in the frames. In addition, the valid frames, in which users place their hands correctly, are selected according to finger gap judgement, and then some key frames, which have good quality, are selected from the valid frames as the gallery samples that are matched with the query samples for authentication decision. The VPR algorithm is conducted on the system designed and developed on mobile device.

• Archives of Plastic Surgery
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• 제49권6호
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• pp.745-749
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• 2022

Background Soft tissue defects of the multiple finger present challenges to reconstruction surgeons. Here, we introduce the use of a lateral arm free flap and syndactylization for the coverage of multiple finger soft tissue defects. Methods This retrospective study was conducted based on reviews of the medical records of 13 patients with multiple soft tissue defects of fingers (n = 33) that underwent temporary syndactylization with a microvascular lateral arm flap for temporary syndactylization from January 2010 to December 2020. Surgical and functional outcomes, times of flap division, complications, and demographic data were analyzed. Results Middle fingers were most frequently affected, followed by ring and index fingers. Mean patient age was 43.58 years. The 13 patients had suffered 10 traumas, 2 thermal burns, and 1 scar contracture. Release of temporary syndactyly was performed 3 to 9 weeks after syndactylization. All flaps survived, but partial necrosis occurred in one patient, who required a local transposition flap after syndactylization release. The mean follow-up was 15.8 months. Conclusion Coverage of multiple finger defects by temporary syndactylization using a free lateral arm flap with subsequent division offers an alternative treatment option.

• 디지털콘텐츠학회 논문지
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• 제18권1호
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• pp.149-158
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• 2017

빅데이터는 경제개발에서 흥미로운 기회와 도전을 보여왔다. 예를 들어, 농업 분야에서 날씨 데이터 및 토양데이터와 같은 복합데이터의 조합과 이들의 분석 결과는 농업종사자 및 농업경영체들에게 귀중하고 도움되는 정보를 제공한다. 그러나 농업 데이터는 센서들과 농업 웹 마켓 등의 다양한 형태의 장치 및 서비스들을 통해 매 분마다 대규모로 생성된다. 이는 데이터 수집, 저장, 분석과 같은 빅데이터 이슈들을 발생시킨다. 비록 몇몇 시스템들이 이 문제를 해결하기 위해 제안되었으나, 이들은 다루는 데이터 종류의 제약, 저장 방식의 제약, 데이터 크기의 제약 등의 문제를 여전히 가지고 있다. 이 논문에서는 농업데이터의 수집과 분석 플랫폼의 새로운 설계를 제안한다. 제안하는 플랫폼은 (1) Flume과 MapReduce를 이용한 다양한 데이터 소스들로부터의 데이터 수집 방법, (2) HDFS, HBase, 그리고 Hive를 이용한 다양한 데이터 저장 방법, (3) Spark와 Hadoop을 이용한 빅데이터 분석 모듈들을 제공한다.

• Journal of the Korean Data and Information Science Society
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• 제24권5호
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• pp.1063-1076
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• 2013

현대 과학기술의 발전으로 빅데이터의 시대가 도래하였다, 이러한 빅데이터는 여러가지 과학적 문제에 대한 해답을 제공하지만 반면에 이로 인해 새로운 도전에 직면하고 있다. 마이크로어레이 자료와 같은 고차원자료는 이러한 빅데이터에서 흔히 볼 수 있는 유형중의 하나이다. 본 논문에서는 고차원 자료분석에 많이 쓰이고 있는 대역검정과 동시검정, 그리고 이의 응용에 대한 소개를 한다.

• Tribology and Lubricants
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• 제29권2호
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• pp.91-97
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• 2013

Quantifying the nanoscale force between the atomic force microscopy (AFM) probe of a force-sensing cantilever and the sample is one of the challenges faced by AFM researchers. The normal force calibration is straightforward; however, the lateral force is complicated due to the twisting motion of the cantilever. Force measurement in a liquid environment is often needed for biological applications; however, calibrating the force of the AFM probes for those applications is more difficult owing to the limitations of conventional calibration methods. In this work, an accurate nondestructive lateral force calibration method using multiple pivot loading was proposed for liquid environment. The torque sensitivity at the location of the integrated probe was extrapolated based on accurately measured torque sensitivities across the cantilever width along a few cantilever lengths. The uncertainty of the torque sensitivity at the location of the integrated tip was about 13%, which is significantly smaller than those for other calibration methods in a liquid environment.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2006년도 학술발표회 논문집
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• pp.571-578
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• 2006

Research using multiple shake tables present new and unique challenges in controls. Typical single shake table tests with large specimens must cope with significant specimen force feedback that can increase tracking error due to specimen gain, damping, and non-linearity. Multiple shaking tables with distributed specimens can produce cross-coupling forces due to inertial and response effects and forces due to static differential displacements. Although many various control architectures exist, basic simplified techniques can yield excellent results without risk to control stability. Off-line simulation techniques can also prove invaluable for studying system response before the real system is operated.

• 아태비즈니스연구
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• 제4권2호
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• pp.1-10
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• 2013

According to the Global Retail Development Index (GRDI) published by A.T. Kearney (2012), India is the $5^{th}$ most attractive retail destination in the world. The retail industry in India has been largely fragmented with small businesses dominating the retail landscape, with very few large players having multiple retail outlets. However, in the last few years, the industry has witnessed a significant growth in the number of large retailers having a chain of outlets across the country. This growth in the organised retail sector has driven primarily by large Indian retail organisations and conglomerates. With the government reducing the restrictions on foreign participation in Indian retail business by increasing the FDI cap on both single and multi-brand retail outlets, the industry is likely to see an explosive growth in the organised retail sector which accounts for only 8 percent of the total industry. With more foreign retailers poised to enter into the country, one of the key issues that the industry may face is finding the right quality of manpower. Literature suggests that in an industry which is characterised by players offering similar kinds of product assortments at similar price levels, success would be governed by the quality of service, which entails employees having the right skills and attitudes for offering quality service. Therefore, the two key issues that may be of importance for retailers are levels of skills and the motivation of the employees. However, according to the National Skill Development Corporation (NSDC, 2009), a significant skill gap exists in the industry, which may widen further in the years ahead, leading to greater challenges for organisations. This paper highlights some of the challenges and issues which characterise the industry in India, and suggests how companies could look at these challenges and seek ways to overcome these challenges.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.149.4-149
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• 2001

In this paper, the multiple micro robot soccer playing system is introduced at first. Learning and evolving in artificial agents is a difficult problem, but on the other hand a challenging task. In our laboratory, this soccer studies mainly centered on single agent learning problem. The construction of such experimental system has involved lots of kinds of challenges such as robot designing, vision processing, motion controlling. At last we will give some results showing that the proposed approach is feasible to guide the design of common agents system.