• Asia pacific journal of information systems
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• v.8 no.2
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• pp.133-159
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• 1998

This essay traverses the ontological space of IS research and identifies various misconceptions, biases, and conceptual peculiarities that inhabit the research. Three aspects of the IS ontology are examined: the conceptualization of the IT construct, demarcation of phenomena for investigation, and conceptual binding of the IT construct to other constructs. Various ontological issues are discussed including the transparency of the IT construct, the objectification of IT, and the causal primacy assigned to IT. The ontological purviews are further explored and their inadequacies are traced in the structurational explication of IS phenomena. At the end, some epistemological implications of the IS ontology are discussed and a two-tier theory structure is proposed for IS research.

• Clinical and Experimental Pediatrics
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• v.55 no.8
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• pp.259-264
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• 2012

Wheezing is one of the most frequent complaints that lead to the use of medical resources in younger children. Generally, wheezing is caused by bronchiolitis and resolves spontaneously without recurrence, but sometimes, wheezing can progress into asthma. Early data on the natural history of childhood wheezing was mostly obtained from retrospective reviews of medical records or from questionnaires, which made it difficult to exclude biases. Now that many cohort studies are available, reviewing the results of birth cohort studies makes it possible to understand the natural course of early childhood wheezing and the risk factors for asthma. In this study, we have reviewed the various phenotypes of early childhood wheezing and their natural courses to help select the most appropriate management modalities for the different types of early childhood wheezing.

• Journal of Digital Convergence
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• v.7 no.1
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• pp.73-80
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• 2009

In this study, the pricing performances of alternative simple option models are examined by creating a simulated market environment in which asset prices evolve according to a stochastic volatility process. To do this, option prices fully consistent with Heston[9]'s model are generated. Assuming this prices as market prices, the trading positions utilizing the Black-Scholes[4] model, a semi-parametric Corrado-Su[7] model and an ad-hoc modified Black-Scholes model are evaluated with respect to the true option prices obtained from Heston's stochastic volatility model. The simulation results suggest that both the Corrado-Su model and the modified Black-Scholes model perform well in this simulated world substantially reducing the biases of the Black-Scholes model arising from stochastic volatility. Surprisingly, however, the improvements of the modified Black-Scholes model over the Black-Scholes model are much higher than those of the Corrado-Su model.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.5
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• pp.676-686
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• 2012

This paper presents a sensor bias estimation method with serial fusion for asynchronous multisensory systems. Serial fusion processes the sensor measurements in a first-come-first-serve basis and it plays an essential role in asynchronous fusion in practice. The proposed algorithm generates the bias measurements using fusion estimates and sensor measurements for bias estimation, and compensates the sensor biases in fusion tracks. A simulation study indicates that the proposed algorithm has the superior performance in bias estimation and accurate tracking.

• Journal of Korean Institute of Industrial Engineers
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• v.23 no.2
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• pp.371-383
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• 1997

This paper propose a fuzzy regression method using fuzzy neural networks when a membership value is attached to each input-output pair. First, a method of linear fuzzy regression analysis is described by interpreting the reliability of each input-output pair as its membership values. Next, an architecture of fuzzy neural networks with fuzzy weights and fuzzy biases is shown. The fuzzy neural network maps a crisp input vector to a fuzzy output. A cost function is defined using the fuzzy output from the fuzzy neural network and the corresponding target output with a membership value. A learning algorithm is derived from the cost function. The derived learning algorithm trains the fuzzy neural network so that the level set of the fuzzy output includes the target output. Last, the proposed method is illustrated by computer simulations on numerical examples.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.918-923
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• 1998

Poly-silicon thin film transistors were fabricated on quartz substrates by high temperature processes. Electrical characteristics were measured and compared for 3 transistor structures of Standard Inverted Gate(SIG), Lightly Doped Drain(LDD), and Dual Gate(DG). Leakage currents of DG and LDD TFT's were smaller that od SIG transistor, while ON-current of LDD transistor is much smaller than that of SIG and DG transistors. Temperature dependence of the leakage currents showed that SIG and DG TFT's had thermal generation current at small drian bias and Frenkel-Poole emission current at hight gate and drain biases, respectively. In case of LDD transistor, thermal generation was the dominant mechanism of leakage current at all bias conditions. It was found that the leakage current was closely related to the reduction of the electric field in the drain depletion region.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1717-1719
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• 2000

DLC films are deposited by using an FCVA deposition system with a mirror-type magnetic field configuration. Permanent magnets and: magnetic yokes around the cathode have been observed to enhance the mobility of arc spots on the cathode and the stability of arc plasma, Effects of reactor pressures and substrate biases on structural properties of DLC films deposited are investigated. The results show that the highest $sp^{3}/sp^{2}$ fraction is obtained when the films are deposited at a pressure of $3{\times}10^4$ Torr and a bias voltage of - 50 V. The variation of the structural properties due to thermal stress up to 500$^{\circ}C$ is also examined.

• English Language & Literature Teaching
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• v.11 no.2
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• pp.51-66
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• 2005

This study investigates the feasibility of incorporating student evaluations of peer review interactions into the course grade for an EFL writing course. The use of such evaluations offers a way to grade the process of writing more directly than using writing portfolios alone. Moreover, evaluating peer review interactions highlights the social aspect of writing, which is valuable in the current post-process climate in writing instruction. The 18 members of a semester-long EFL writing course at a Korean university were trained in peer response for one half of a semester; then performed evaluations of peer review interactions during the second half of the semester as part of their writing course. Student evaluations were examined to reveal whether any bias occurred due to relative age, gender, major, or question type. The results revealed no such biases. Therefore, it is suggested that students are capable of providing fair evaluations of peers, which means the evaluations can be factored into the course grade in order to evaluate the social aspect of the writing process.

• BMB Reports
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• v.51 no.4
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• pp.167-173
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• 2018

Experimental results obtained from research using only one sex are sometimes extrapolated to both sexes without thorough justification. However, this might cause enormous economic loss and unintended fatalities. Between years 1997 and 2000, the US Food and Drug Administration suspended ten prescription drugs producing severe adverse effects on the market. Eight of the ten drugs caused greater health risks in women. Serious male biases in basic, preclinical, and clinical research were the main reason for the problem. This mini-review will describe why and how funding organizations such as the European Commission, the Canadian Institutes of Health Research, and the US National Institutes of Health have tried to influence researchers to integrate sex/gender not only in clinical research, but also in basic and preclinical research. Editorial policies of prominent journals for sex-specific reporting will also be introduced, and some considerations in integrating sex as a biological variable will be pointed out. To produce precise and reproducible results applicable for both men and women, sex should be considered as an important biological variable from basic and preclinical research.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.12
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• pp.1243-1251
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• 2007

In this paper a study on the simplified observability analysis of GPS/INS is introduced. Errors for the position, velocity, attitude, gyro and accelerometer biases, and lever arm between GPS antenna and inertial sensors are considered in the observablity analysis. From the error dynamics model in which relatively small terms are neglected, simple observability conditions are obtained such that the observability of GPS/INS is determined by the test on the attutude, gyro bias, and lever arm. Unobservable errors for the position, velocity, and accelerometer bias are determined by those for the attitude, gyro bias, and lever arm. The simplified observability conditions are applied to a constant speed horizontal motion. It is shown that there are seven unobservable modes for the motion including the vertical component of gyro bias. The analytic observability analysis results are confirmed with a covariance simulation.