• The Mathematical Education
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• v.46 no.4
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• pp.357-369
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• 2007

Teachers and students' knowledge of zero was investigated through data collected from 16 preservice secondary mathematics teachers and 20 gifted secondary school students. Results showed that these teachers and students had an inadequate knowledge about zero. They exhibited a reluctance to accept zero as an attribute for classification, confusion as to whether or not zero is a number, and stable patterns of computational error. Although leachers and researchers have long recognized the value of analyzing student errors for diagnosis and remediation, students have not been encouraged to take advantage of errors as learning opportunities in mathematics instruction. The article suggests using errors as springboards for inquiry in action, discusses its potential contributions to mathematics instruction by analyzing students and preservice teachers errors related to zero.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.5
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• pp.1010-1018
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• 2009

An inertial navigation system for pedestrian position tracking is proposed, where the position is computed using inertial sensors mounted on shoes. Inertial navigation system(INS) errors increase with time due to inertial sensor errors, and therefore it needs to reset errors frequently. During normal walking, there is an almost periodic zero velocity instance when a foot touches the floor. Using this fact, estimation errors are reduced and this method is called the zero velocity updating algorithm. When implementing this zero velocity updating algorithm, it is important to know when is the zero velocity interval. The gait states are modeled as a Markov process and each state is estimated using the hidden Markov model smoother. With this gait estimation, the zero or nearly zero velocity interval is more accurately estimated, which helps to reduce the position estimation error.

• Research in Mathematical Education
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• v.18 no.2
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• pp.149-170
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• 2014

The Vietnamese language has a specific property related to the zero in the name-number system. This study was conducted to examine the impact of linguistic differences and of the zero's position in a number on a transcoding task (verbal number into Arabic number). Vietnamese children and French-speaking Belgian children, from grades 3 to 6, participated in the study. The success rate and the type of errors they made varied, depending on their grade and language. At Grade 4, Vietnamese children showed performances equivalent to Grade 6 Belgian children. Our results confirmed the support provided by language to the understanding and performances in a transcoding task. Results also showed that a syntactic zero is easier to manipulate than a lexical zero for Vietnamese children. The relative influence of language and the source of errors are discussed.

• Proceedings of the KIEE Conference
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• 1998.11a
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• pp.220-222
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• 1998

This paper presents a method, which develops an ability of Zero-phase Overcurrent Relay. Zero-phase current is very useful factor of Fault decision in Protect Relaying system. Actually, the setting-point value of Designed Relay, using Zero-phase current, is fixed. So in the case of deciding fault, Fixed setting-point value is not suitable for changing Load. and cause errors in Distributions system. For solving this problem, This paper proposes the Changed setting point value Algorithm, which can be adaptive for changing Distributions system using Zero-phase current r.m.s. indexes. The results of simulation under Load changing and High impedance fault show that proposed algorithm is useful for changing Distributions system and decreasing errors.

• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.386-388
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• 2007

In many applications of UAVs flying in low altitude, the steady supply of accurate height measurements is very important for the UAVs to complete their mission successfully. In order to do this, a barometer or GPS height measurements are widely used. However, because these two sensors have their limitations in the application environment, a method for fusing these two measurements to produce reference heights are required. In this paper, a reference height generation filter is designed for UAV(Unmanned Air Vehicle) applications. The barometer errors originated by the change of the atmospheric environment are modeled using random walk models, and then the errors are identified and compensated through the ZSB(zero-scan-back) filter algorithm using the GPS height measurements. The performance of the proposed filter is demonstrated by realistic simulations.

• Journal of Internet Computing and Services
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• v.15 no.5
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• pp.17-24
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• 2014

Blind algorithms designed to maximize the probability that constant modulus errors become zero carry out some summation operations for a set of constant modulus errors at an iteration time inducing heavy complexity. For the purpose of reducing this computational burden induced from the summation, a new approach to the estimation of the zero-error probability (ZEP) of constant modulus errors (CME) and its gradient is proposed in this paper. The ZEP of CME at the next iteration time is shown to be calculated recursively based on the currently calculated ZEP of CME. It also is shown that the gradient for the weight update of the algorithm can be obtained by differentiating the ZEP of CME estimated recursively. From the simulation results that the proposed estimation method of ZEP-CME and its gradient produces exactly the same estimation results with a significantly reduced computational complexity as the block-processing method does.

• School Mathematics
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• v.11 no.4
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• pp.567-581
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• 2009

Many articles have reported that zero causes children's arithmetic errors. This article was designed to measure the effect of zero on children's arithmetic performances. For this, 222 of 3,4,5,6 graders in elementary school were tested with pencil and paper. The test were categorized into four parts: basic number fact, column subtraction, column multiplication, and column division. These data showed that the negative effect of zero on children's arithmetic was limited to several areas, concretely, multiplication facts with zero, column subtraction with numbers which have two successive zeros, column multiplication with numbers which have zero in a middle position, long division with zeros. But there was no evidence that students could self-control these negative effects of zero as grade went up. It implies that we should keep attention to children's arithmetic performance with zero in some special areas.

• IEIE Transactions on Smart Processing and Computing
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• v.6 no.1
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• pp.1-9
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• 2017

This paper proposes to improve the performance of a strap down inertial navigation system using a foot-mounted low-cost inertial measurement unit/magnetometer by configuring an attitude and heading reference system. To track position accurately and for attitude estimations, considering different dynamic constraints, magnetic measurement and a zero velocity update technique is used. A conventional strap down method based on integrating angular rate to determine attitude will inevitably induce long-term drift, while magnetometers are subject to short-term orientation errors. To eliminate this accumulative error, and thus, use the navigation system for a long-duration mission, a hybrid configuration by integrating a miniature micro electromechanical system (MEMS)-based attitude and heading detector with the conventional navigation system is proposed in this paper. The attitude and heading detector is composed of three-axis MEMS accelerometers and three-axis MEMS magnetometers. With an absolute algorithm based on gravity and Earth's magnetic field, rather than an integral algorithm, the attitude detector can obtain an absolute attitude and heading estimation without drift errors, so it can be used to adjust the attitude and orientation of the strap down system. Finally, we verify (by both formula analysis and from test results) that the accumulative errors are effectively eliminated via this hybrid scheme.

• Communications for Statistical Applications and Methods
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• v.3 no.1
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• pp.243-255
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• 1996

The number of neutron signals from a neutral particle beam(NPB) at the detector, without any errors, obeys Poisson distribution, Under two assumptions that NPB scattering distribution and aiming errors have a circular Gaussian distribution respectively, an exact probability distribution of signals becomes a Poisson-power function distribution. In this paper, we show that the error rate in simple hypothesis testing for the limiting Poisson-power function distribution is not zero. That is, the limit of ${\alpha}+{\beta}$ is zero when Poisson parameter$\kappa\rightarro\infty$, but this limit is not zero (i.e., $\rho\ell$>0)for the Poisson-power function distribution. We also give optimal decision algorithms for a specified error rate.

• Communications for Statistical Applications and Methods
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• v.8 no.1
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• pp.291-297
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• 2001

For a stochastic regression model in which the errors are assumed to form a stationary linear process, we show that the difference between the empirical distribution functions of the errors and the estimates of those errors converges uniformly in probability to zero at the rate of $o_{p}$ ( $n^{-}$$\frac{1}{2}$) as the sample size n increases.