• Design & Manufacturing
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• v.12 no.2
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• pp.11-15
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• 2018

In this study, we proposed three analysis methods to calculate the flatness of torque-angle sensors (TAS). We introduced two statistical and one geometrical methods in evaluating the precision of the flat plane in the axis direction for TAS. To verified the results, we fabricated TAS and a reference sample using a injection molding machine, mold, polyester as a raw material. We measured ($x_i$, $y_i$) position using 3D contact automated system and applied three analysis methods developed for TAS and a reference sample to see the feasibility. While each analysis method has its own pros and cons, the analysis using the shortest optimal distance was the most precise technique for the flatness evaluation of TAS components.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.658-668
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• 2009

Earth-moving operation has a great impact on the overall budget and schedule of any heavy civil projects. More often than not, the operational decisions are made largely based on field personnel's experience and judgment. In particular, decisions on earth moving operations by scraper-dozer fleets have been heavily influenced by the following belief: "The longer a dozer pushes a scraper for loading, the better earth-moving productivity is gained by the fleet." Even though there is some truth to this notion, scraper-dozer earth moving operations involve a much complex process that requires a systematic analysis for predicting the maximum production. To this end, this paper presents a spreadsheet-based scraper-dozer fleet operation model for its production optimization. Various optimization techniques, including a genetic-algorithm method, are presented for comparison and each technique's pros and cons are discussed.

• Asian review of World Histories
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• v.1 no.2
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• pp.189-226
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• 2013

Discussions of world history often focus on the pros and cons of thinking on large spatial scales. However, world history also tends to employ unusually large timescales, both for research and teaching; frequently it is framed around a teleology and a series of "revolutions" which mark milestones taking humans from a very distant past to "modernity". Moreover, world history usually rejects regionally specific period markers (e.g. Renaissance), making periodization within this long timespan especially difficult. This article surveys various approaches to these problems, and shows that any of them, if treated as sufficient by itself, introduces significant distortions. It argues for a world history that highlights this problem, rather than hiding it, and which uses the need to deploy multiple timescales simultaneously to clarify the distinctive intellectual contribution of historical thinking.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.815-820
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• 2002

MSC as a payload of KOMPSAT-2 is an optical telescope for earth imaging on a sun-synchronous orbit. The MSC is a Ritchey-Chretien type telescope composed of hyperbolic primary and secondary mirrors with focal correcting lenses. Their relative positions should be kept aligned during imaging operation. However, the MSC is exposed to adverse thermal environment on orbit which can have some impacts on optical performance as well as structural endurance. Solar incidence can cause non-uniform temperature rise on the tube which entails unfavorable thermal distortion. Three options were proposed, which were internal shield, external mechanical shield and spacecraft maneuvering. After the trade-off studies, internal sun shield was selected as a realistic and optimal solution to minimize the effect of the solar radiation. In this paper, pros and cons are explained for the three possible choices and a design of the internal shield is discussed.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.4
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• pp.529-537
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• 1998

Appropriate performance evaluation is a key successful factor for continuous improvement and systematic management support in the implementation of quality management. This research deals with the development of a computer support system for performance evaluation of quality management and its application to a real world problem. It, first, investigates existing performance evaluation methods and classifies them into three styles. A number of key factors for designing computer support systems are then elicited by analyzing the characteristics of the existing methods in terms of the requirements needed for a successful evaluation tool. The computer support system is designed by incorporating the key factors in the system design process and it is implemented as a network version. Finally, a case study is performed in order to verify the proposed support system. The pros and cons of the system are also discussed.

• Clinics in Shoulder and Elbow
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• v.20 no.4
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• pp.244-249
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• 2017

Shoulder kinematics is important, as it is associated with shoulder arthropathy and pain mechanisms. Various static and dynamic analysis methods are prevalent for shoulder kinematics. These include 2-dimensional plane x-ray, computed tomography, and magnetic resonance imaging, cadaver study, electromagnetic motion analysis, transcortical bone pins technique, and in vivo 3-dimensional motion analysis. Although these methods provide the value of the shoulder kinematics angle, they are unable to explain why such changes occur. Since each method has its pros and cons, it is important to understand all factors accurately, and to choose a method that best meets the purpose of the researcher.

• Journal of Nutrition and Health
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• v.30 no.6
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• pp.727-732
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• 1997

Dietary supplements are generally defined as concentrated sources of nutrients prescribed in addition to the daily diet to increase nutrient intake. These supplements are usually in the form of tablets, capsules, pills, powders, or liquids. Sales of dietary supplements are roughly $4 billion per year in the United States. Nearly 4 out of every 10 adults use dietary supplements regularly. This article is to report the pros and cons in the use of dietary supplements and a brief overview of current law, proposed regulations, and related activities in the United States. It provides what information should be known to the public before federal regulations governing health claims are made . These regulations may decide whether health food industries or pharmaceutical companies can make claims about the function of nutrients.

• Journal of Power Electronics
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• v.18 no.5
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• pp.1585-1594
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• 2018

The estimation of $LiFePO_4$/graphite battery states suffers from the prominent hysteresis phenomenon between the respective open-circuit voltage curves towards charging and discharging. A lot of hysteresis models have been documented to investigate the hysteresis mechanism. This paper reviews and deeply interprets four non-electrochemical hysteresis models and some improvements. These models can be conveniently incorporated into commonly used equivalent circuit models to reproduce battery behaviors. Through simulation and experimental comparisons of voltage predictions and state-of-charge estimations, the pros and cons of these models are presented.

• Journal of the Korean Solar Energy Society
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• v.37 no.5
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• pp.49-63
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• 2017

Solar cells have widely been utilized for a satellite to convert sunlight energy into electricity in space. Many different types of solar cells appropriate for each satellite program are available in current markets, which enables us to construct a solar array light and small often required from a low Earth orbit (LEO) synthetic aperture radar (SAR) satellite. Thus, it is important to choose a proper solar cell satisfying the requirements of mass and size for the solar array. In this article, we have surveyed typical suppliers and have discussed some characteristics of solar cells. Conceptual design examples of the solar array for LEO SAR satellites using several types of solar cells have been performed to show the pros and cons of solar cells by comparison of the total mass and size necessary for the solar array.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.9
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• pp.75-80
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• 2000

Although laser interferometer is widely accepted as a tool for measurement of motion accuracy the set-up procedure is time-consuming because of the strict requirement on alignment between laser head and optic units. This paper presents a 4-axis auto-aligning system which is useful for easy set-up of laser interferometer so as to evaluate precision of a 2-axis feeding system. This paper proposes two ideas for alignment in laser interferometer set-up: one is use of mirror and retroreflectors. and the other is taking advantage of the pre-defined movement and peculiar characteristic of retroreflecotrs. The pros and cons of the two methods are discussed. Illustrative experimental results are presented in which the developed system is applied to a XY table.