• Journal of Broadcast Engineering
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• v.24 no.5
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• pp.765-774
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• 2019

In this paper, we propose a point cloud matching algorithm for multiple RGB-D cameras. In general, computer vision is concerned with the problem of precisely estimating camera position. Existing 3D model generation methods require a large number of cameras or expensive 3D cameras. In addition, the conventional method of obtaining the camera external parameters through the two-dimensional image has a large estimation error. In this paper, we propose a method to obtain coordinate transformation parameters with an error within a valid range by using depth image and function optimization method to generate omni-directional three-dimensional model using 8 low-cost RGB-D cameras.

• Current Optics and Photonics
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• v.6 no.2
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• pp.161-170
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• 2022

Three-dimensional (3D) geometric models are introduced to correct vignetting, and a downhill simplex search is applied to determine the coefficients of a 3D model used in digital microscopy. Vignetting is nonuniform illuminance with a geometric regularity on a two-dimensional (2D) image plane, which allows the illuminance distribution to be estimated using 3D models. The 3D models are defined using generalized polynomials and arbitrary coefficients. Because the 3D models are nonlinear, their coefficients are determined using a simplex search. The cost function of the simplex search is defined to minimize the error between the 3D model and the reference image of a standard white board. The conventional and proposed methods for correcting the vignetting are used in experiments on four inspection systems based on machine vision and microscopy. The methods are investigated using various performance indices, including the coefficient of determination, the mean absolute error, and the uniformity after correction. The proposed method is intuitive and shows performance similar to the conventional approach, using a smaller number of coefficients.

• Journal of Korean Society of Water and Wastewater
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• v.36 no.5
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• pp.275-287
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• 2022

In order to overcome the small scale of Korea waterworks and to achieve comprehensive improvement and innovation transformation, the waterworks integration was reviewed. The effect of consolidation was confirmed by the integration of the water supply business in the southern Gangwon region and the western Gyeongnam region in Korea, such as an increase in the flow rate and a decrease in the production unit cost. After facing management and service limitations overseas, more than 1,000 small-scale waterworks projects in the UK were integrated into 27 waterworks providers, and Japan also revised the Waterworks Act in December 2019 and is in the process of integrating waterworks. It is considered appropriate to promote the integration of waterworks projects in Korea by respecting the autonomy of local governments, but using a participatory method, a win-win method, and a linkage method. For the integration of waterworks projects, three strategies are proposed: First creating a national foundation for integration (revision of the Waterworks Act), Second establishing a waterworks integration strategy led by local governments, Third forming an external consensus and providing incentives for participation.

• International Journal of Computer Science & Network Security
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• v.23 no.9
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• pp.162-165
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• 2023

Power can be generated from either renewable or non-renewable sources. Renewable sources are liked to maintain a strategic distance from contamination emanation and rely on upon fossil energizes which is decreasing day by day. The proposed sun powered vitality transformation unit comprises of a sun oriented exhibit, Bidirectional DC-DC converter, single stage inverter and AC. The inverter changes over DC control from the PV board into AC power and offered it to the heap which is associated with the lattice. The photovoltaic sun powered vitality (PV) is the most direct approach to change over sunlight based radiation into power and depends on the photovoltaic impact. The most extreme power point following of the PV yield for all daylight conditions is a key to keep the yield control per unit cost low for fruitful PV applications. Framework associated PV frameworks dependably have an association with people in general power matrix by means of an appropriate inverter in light of the fact that a PV module conveys just dc power. This project presents the new design, Development and Performance Analysis of a Grid Connected PV Inverter. Demonstrate that the proposed framework can lessen the Energy Consumption radically from the power board and give a solid support to the Grid.

• Asia pacific journal of information systems
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• v.31 no.1
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• pp.102-120
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• 2021

E-learning is a planned effort towards providing interactive and experiential learning having flexibility in terms of time, place, pace, participation and accessibility. Globalization has set the stage for a social transformation of the world economy driven by technological innovation, emphasizing knowledge-based processes. While the tertiary education enrolments in wealthy nations have gone up incrementally, the same cannot be said to be right about developing economies. E-Learning can streamline enrolments to higher education, in developing nations by being a cost-effective and flexible alternative. The objective of this paper is to draw attention to the similarities in the national culture of these two countries and compare students' perception on e-learning in India and Sri Lanka along eight dimensions viz., viability, dependability, flexibility, inclusivity, power, pertinence, challenge and equitability. The results reveal that e-learning is equally popular among students from both countries, and they have a high perception score towards e-learning on each of the measured eight dimensions. Hence results are indicative of an opportunity of tapping the potential of e-learning in reaching out to a broader audience of underprivileged students and onboarding them into the knowledge economy.

• Information Systems Review
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• v.25 no.4
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• pp.1-25
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• 2023

The online fitness industry has experienced rapid growth in recent years, overcoming physical constraints of conventional fitness programs. The COVID-19 pandemic accelerated the trend as social distancing policies were implemented. However, as financial distress of offline gyms worsened, the Korean government implemented the "With-COVID19" policy, which lifted most of the restrictions and regulations on offline gyms, on November 1st, 2021, raising concerns about the loss of drivers for the growth of the online fitness industry. Using regression discontinuity design in time (RDDiT), this study investigates the causal effect of the "With-COVID19" policy on the viewer engagement of online fitness content. Contrary to expectations that viewer engagement would decrease, it increased by 21%. Additionally, subgroup analysis based on opportunity cost reveals heterogeneity, and the high-cost group experienced a greater increase of 32% compared to low-cost group. Based on these findings, the study provides possible mechanisms of the increase, theoretical contributions on using RDDiT in the Information Systems, and practical implications for guidelines on managing online fitness platforms and content in the era of digital transformation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.6C
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• pp.561-570
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• 2009

Ultra-wideband communication systems based on impulse radio have merits that are possible for the high data rate transmission, high resolution ranging are positioning system. Conventionally, in order to accomplish these features, the high-speed ADC (Analog to Digital Convertor) is necessary to apply radio determination system operating in time domain. However, considering low rate - wireless personal area network (LR-WPAN) aims to low-cost hardware implementation, the expensive ADC converting GHz sampling per second is not appropriate. So, this paper introduces a low complex AR (Auto Regressive) model based non-coherent ranging scheme operating in frequency domain with using low-speed ADC utilizing analog Voltage Control Oscillator (VCO) mode for the frequency domain transformation. To verify the superiority of the proposed ranging and location algorithm working in frequency domain, the suggested IEEE 802.15.4a TG channel model is used to exploit affirmative features of the proposed algorithm with conducting the simulation results.

• Convergence Security Journal
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• v.3 no.2
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• pp.41-55
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• 2003

Today the traditional national intelligence activities which are mainly based on classified informations are confronted with several problems. These are excessive collection cost, morality of intelligence activity, objectivity of intelligence, intelligence dead zone and timeliness of intelligence etc. On the other hand, circumstances of national intelligence activity are rapidly changed. Those are rapid growth of internet, transformation of classified information into open one and rapid growth of intelligence capabilities of private sector. To cope these problems and circumstances, we reevaluated OSINT(Open Source INTelligence) which is collected from all kinds of open source informations on the internet. First, we classified OSINT into four categories corresponding to the traditional classified collection methods i.e., IMINT, SIGINT, HUMINT and MASINT. And we evaluate the value of OSINT in comparison with classified collection methods. Finally a system for national intelligence activity based on all kinds of open source intelligence on the internet is proposed, described and compared with the system of traditional national intelligence activity.

• Smart Structures and Systems
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• v.3 no.2
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• pp.189-200
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• 2007

As a functional material, shape memory alloy (SMA) has attracted much attention and research effort to explore its unique properties and its applications in the past few decades. Some of its properties, in particular the electrical resistance (ER) based self-sensing property of SMA, have not been fully studied. Electrical resistance of an SMA wire varies during its phase transformation. This variation is an inherent property of the SMA wire, although it is highly nonlinear with hysteresis. The relationship between the displacement and the electrical resistance of an SMA wire is deterministic and repeatable to some degree, therefore enabling the self-sensing ability of the SMA. The potential of this self-sensing ability has not received sufficient exploration so far, and even the previous studies in literature lack generality. This paper concerns the utilization of the self-sensing property of a spring-biased Nickel-Titanium (Nitinol) SMA actuator for two applications: ER feedback position control of an SMA actuator without a position sensor, and estimation of the opening of a SMA actuated valve. The use of the self-sensing property eliminates the need for a position sensor, therefore reducing the cost and size of an SMA actuator assembly. Two experimental apparatuses are fabricated to facilitate the two proposed applications, respectively. Based on open-loop testing results, the curve fitting technique is used to represent the nonlinear relationships between the displacement and the electrical resistance of the two SMA wire actuators. Using the mathematical models of the two SMA actuators, respectively, a proportional plus derivative controller is designed for control of the SMA wire actuator using only electrical resistance feedback. Consequently, the opening of the SMA actuated valve can be estimated without using an extra sensor.

• Journal of the Korea Computer Industry Society
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• v.7 no.3
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• pp.191-198
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• 2006

Area of software measurement is active more than thirty years. There is a huge collection of researches but still no concrete software development effort, duration and cost estimation model. The data sets used to conduct previous studies in the duration estimation model are often small and not too recent, these types of models should not be apply in recent projects that have complex architecture and various development environment. Therefore, Oligny et al. presents empirical models that predict software project duration in accordance with project platform based on project effort using the log data transformation. These models are based on the analysis of 396 project data provided by release 4 of the ISBSG Benchmark. Applying Oligny et al.'s models to 534 project data provided release 6 of the ISBSG Benchmark, the project duration is affected by development type more than development platform. Therefore, This paper presents the model of duration estimation according to development type. This paper proves the duration is more affected by development type than development platform. And, The model according to development type is more adequate for duration estimation.