• Journal of Power Electronics
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• v.19 no.6
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• pp.1544-1553
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• 2019

The efficiency of photovoltaic generation systems depends on the maximum power point tracking (MPPT) technique. Among the various schemes presented in the literature, the incremental conductance (INC) method is one of the most frequently used due to its superb tracking ability under changes in insolation and temperature. Generally, conventional INC algorithms implement a simple duty-cycle updating rule that is mainly found on the polarity of the peak-power evaluation function. However, this fails to maximize the performance in both steady-state and transient conditions. In order to overcome this limitation, a novel regulated INC (r-INC) method is proposed in this paper. Like the compensators in automatic control systems, this method applies a digital compensator to evaluate the INC function and improve the capability of power tracking. Precise modeling of a new MPPT system is also presented in the optimized design process. A 120W boost peak power tracker is utilized to obtain comparative test results and to confirm the superiority of the proposed method over existing techniques.

• Journal of Internet Computing and Services
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• v.21 no.2
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• pp.39-48
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• 2020

Data mining techniques have been suggested to find efficiently meaningful and useful information. Especially, in the big data environments, as data becomes accumulated in several applications, related pattern mining methods have been proposed. Recently, instead of analyzing not only static data stored already in files or databases, mining dynamic data incrementally generated in a real time is considered as more interesting research areas because these dynamic data can be only one time read. With this reason, researches of how these dynamic data are mined efficiently have been studied. Moreover, approaches of mining representative patterns such as maximal pattern mining have been proposed since a huge number of result patterns as mining results are generated. As another issue, to discover more meaningful patterns in real world, weights of items in weighted pattern mining have been used, In real situation, profits, costs, and so on of items can be utilized as weights. In this paper, we analyzed weighted maximal pattern mining approaches for data generated incrementally. Maximal representative pattern mining techniques, and incremental pattern mining methods. And then, the application scenarios for analyzing the required commodity patterns in infants are presented by applying weighting representative pattern mining. Furthermore, the performance of state-of-the-art algorithms have been evaluated. As a result, we show that incremental weighted maximal pattern mining technique has better performance than incremental weighted pattern mining and weighted maximal pattern mining.

• Proceedings of the Korean Society of Rheology Conference
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• 2003.05a
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• pp.93-98
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• 2003

In this paper, the main emphasis and focus will be to study and illuminate the nature of Plastic Energy Dissipation (PED) in variety of polymers. This PED term represents the heat generated during the irreversible deformation of a polymer solid. A series of experiments for various polymers have been conducted in direct measurement method and indirect evaluation method - the incremental strain stress relaxation ((ISSR) method. The experimental evidence to relate the stress relaxation and the sensible temperature rise were revealed by the series of direct method experiments.

• IE interfaces
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• v.1 no.2
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• pp.1-12
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• 1988

A justification methodology which evaluates the tactical aspects of an FMS project is proposed. For evaluation of quantifiable tactical costs/savings a method of internal rate of return on incremental investment is developed while for the tactical ones which are difficult to quantify a weighted factor scoring model is proposed.

• Journal of Korean Society for Quality Management
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• v.14 no.2
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• pp.9-14
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• 1986

The primary purpose of this paper is to make the management of small business aware of the potential and further, to assist their decision on purchasing and applying the personal computers to their business problems. With emphasis on the step by step expansion various computer hardware systems are reviewed, compared and evaluated in its price, micro-processor, memory size, software availability, etc. Using the concept of incremental costs, a method to evaluate software packages is developed. By this method the optimal system can be determined.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.915-916
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• 2009

프로그램 개발 단계에서 프로그램을 수정할 경우, 전체 프로그램을 다시 평가하는 대신 수정한 부분과 그 부분에 영향 받는 부분만을 다시 평가하는 것이 점진 평가 방법이다. 본 논문에서는 의미 구조에 직접적으로 영향을 주는 변수의 값을 나타내는 속성을 중심으로 종속성을 표시하고, 여러 프로세서에서 병렬로 처리하는 대신 멀티쓰레딩 기능을 활용하여 객체 지향언어인 자바 언어에서 점진 평가를 동시에 효율적으로 수행할 수 있는 병행 점진 평가 방법을 제시하고 모의실험을 통해 병행 점진 평가 방법의 효율성을 분석한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.883-884
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• 2009

프로그램 개발 단계에서 소요되는 비용을 최소화하기 위해 점진 평가 방법이 사용되고 있다. 점진 평가는 프로그램을 모두 다시 평가하는 대신 수정한 부분과 그 부분에 영향 받는 부분만을 다시 평가하는 방법으로 프로그램의 실행 효율성을 향상시킬 수 있는 중요 분야이다. 본 논문에서는 자바 같은 언어에서 확장된 종속차트의 종속 링크를 사용해 변수의 값이 변경되었을 때 그 부분에 영향 받는 부분을 찾아내는 변화 추적 과정을 통하여 효율적인 점진 평가를 수행할 수 있는 방법을 제시한다. 모의실험을 통해 점진 평가의 효율성을 분석한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.433-436
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• 2008

프로그램의 생산성을 향상시키기 위해 프로그램 개발 단계에서 소요되는 비용을 최소화하려는 목적으로 점진 평가를 사용하고 있다. 점진 평가는 전체 프로그램을 다시 평가하는 대신 수정한 부분과 그 부분에 영향 받는 부분만을 다시 평가하는 방법이다. 본 논문에서는 기존의 종속 차트(dependency chart)를 확장하여 객체 지향언어인 자바 같은 언어에서 점진 평가를 수행할 수 있도록 확장된 종속 차트를 제시한다. 객체 지향언어에서 점진 평가를 수행하는 알고리즘을 제시하고 실험을 통해 점진 평가의 효율성을 분석한다.

• Steel and Composite Structures
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• v.23 no.1
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• pp.95-105
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• 2017

The use of superelastic shape memory alloys (SMAs) as reinforcements in concrete structures is gradually gaining interest among researchers. Because of different mechanical properties of SMAs compared to the regular steel bars, the use of SMAs as reinforcement in the concrete may change the response of structures under seismic loads. In this study, the effect of SMAs as reinforcement in concrete structures is analytically investigated for 3-, 6- and 8-story reinforced concrete (RC) buildings. For each concrete building, three different reinforcement details are considered: (1) steel reinforcement (Steel) only, (2) SMA bar used in the plastic hinge region of the beams and steel bar in other regions (Steel-SMA), and (3), beams fully reinforced with SMA bar (SMA) and steel bar in other regions. For each case, columns are reinforced with steel bar. Incremental Dynamic Analyses (IDA) are performed using ten different ground motion records to determine the seismic performance of Steel, Steel-SMA and SMA RC buildings. Then fragility curves for each type of RC building by using IDA results for IO, LS and CP performance levels are calculated. Results obtained from the analyses indicate that 3-story frames have approximately the same spectral acceleration corresponding with failure of frames, but in the cases of 6 and 8-story frames, the spectral acceleration is higher in frames equipped with steel reinforcements. Furthermore, the probability of fragility in all frames increases by the building height for all performance levels. Finally, economic evaluation of the three systems are compared.

• Korean Journal of Ecology and Environment
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• v.46 no.1
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• pp.10-17
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• 2013

History of Instream Flow Incremental Methodology (IFIM) Following the large reservoir and water development era of the mid-twentieth century in North America, resource agencies became concerned over the loss of many miles of riverine fish and wildlife resources in the arid western United States. Consequently, several western states began issuing rules for protecting existing stream resources from future depletions caused by accelerated water development. Many assessment methods appeared during the 1960's and early 1970's. These techniques were based on hydrologic analysis of the water supply and hydraulic considerations of critical stream channel segments, coupled with empirical observations of habitat quality and an understanding of riverine fish ecology. Following enactment of the National Environmental Policy Act (NEPA) of 1970, attention was shifted from minimum flows to the evaluation of alternative designs and operations of federally funded water projects. Methods capable of quantifying the effect of incremental changes in stream flow to evaluate a series of possible alternative development schemes were needed. This need led to the development of habitat versus discharge functions developed from life stage-specific relations for selected species, that is, fish passage, spawning, and rearing habitat versus flow for trout or salmon. During the late 1970's and early 1980's, an era of small hydropower development began. Hundreds of proposed hydropower sites in the Pacific Northwest and New England regions of the United States came under intensive examination by state and federal fishery management interests. During this transition period from evaluating large federal reservoirs to evaluating license applications for small hydropower, the Instream Flow Incremental Methodology (IFIM) was developed under the guidance of the U.S. Fish and Wildlife Service (USFWS).