Circle Test Research Articles

A coverage-preserving scheme for wireless sensor network with irregular sensing range

Coverage is an important issue related to WSN quality of service. Several centralized/decentralized solutions based on geometry information and under the assumption of disk sensing range have been introduced in the literature. However, disk sensing range assumption is too strong in the real world and cannot be held in scenarios requiring high accuracy, such as the emergency preparedness class of applications. This paper proposes a new intersection point method (IPM) that extends the disk sensing range assumption to an irregular simple polygon assumption. A unit circle test method has also been devised in order to provide a controllable degree of accuracy in the determination of fully covered nodes. By adjusting the radius r u of this unit circle test, the algorithm can be made tolerant to holes of a certain size which makes the solution flexible when the degree of accuracy must be controlled. IPM performance was evaluated through a set of simulation experiments implemented in the NS-2 simulator, which were compared to the results obtained using the central angle method (CAM) proposed by D. Tian and N.D. Georganas, and the association sponsors method (ASM) proposed by A. Boukerche, X. Fei and Regina B. Araujo. The results show that under the simple polygon sensing range assumption, our solution can efficiently identify fully covered sensors, discover holes (blind points) and archive better quality results than CAM and ASM. The performance and flexibility of IPM makes it a potential solution for applications that require a high rate of coverage with controllable hole tolerance.

A novel simple and low cost 4 degree of freedom angular indexing calibrating technique for a precision rotary table

For calibrating an angular rotary table, either a high precision standard table or a laser interferometer and related optics are normally employed at high cost. This paper establishes a novel, simple and low cost technique to calibrate the 4-degrees-of-freedom (DOF) errors of a rotary table (three angular position errors and one linear position error) for a 360° full circle by employing one reference rotary table, one 1 dimensional (1D) grating and two 2 dimensional (2D) position-sensing-detectors (PSD). With this technique, no highly accurate reference rotary table, but with good repeatability is needed. After two full circle tests, the 4-DOF errors of both the target rotary table and the reference rotary table could be obtained. The system calibration, stability test, system verification and full circle test were completed. The angular stability of this system was less then 2 arc sec, while the displacement stability was less than 1.2 μm.

Effects of punch load for elliptical deep drawing product of automotive parts

Deep drawing process, one of sheet metal forming methods, is very useful in industrial field because of its efficiency. The production of optimal products using this process is dependent on the process variables such as blank shapes, profile radii of punch and die, and formability of materials. Of the variables, the blank shape is very important since it controls the formability factor. This paper reports the investigations on three kinds of blank shapes and the scribed circle test on three deformation modes. The punch load distribution for elliptical forming processes were measured under different conditions of profile radii of punch and die and discussed here. These experiments clarified the influence of the profile radii of the punch and die and the blank shape on the punch-load distribution for the elliptical deep drawing product of automobile parts. The aim of this study is to investigate the effect that the process variables have on drawability in a non-axisymmetric elliptical deep-drawing process and to obtain useful data from the industrial field.

Foreground contamination of the WMAP CMB maps from the perspective of the matched circle test

WMAP has provided CMB maps of the full sky. The raw data is subject to foreground contamination, in particular near to the Galactic plane. Foreground cleaned maps have been derived, e.g., the internal linear combination (ILC) map of Bennett et al. and the reduced foreground TOH map of Tegmark et al. Using S statistics we examine whether residual foreground contamination is left over in the foreground cleaned maps. In particular, we specify which parts of the foreground cleaned maps are sufficiently accurate for the circle-in-the-sky signature. We generalise the S statistic, called D statistic, such that the circle test can deal with CMB maps in which the contaminated regions of the sky are excluded with masks.

Overall studies on the IMO manoeuvrability standard and problems arising in application of the criteria of it to various kinds of vessels

The IMO manoeuvrability standard was established for preventing sea accidents such as collisions and strandings due to the lack of manoeuvrability. The standard of ship manoeuvrability enforced by resolution MSC.l37(76) has been applied to vessels of 100m or more in length and all chemical tankers and gas carriers regardless of the length, which were constructed on or after 1 July 1994. The IMO manoeuvrability standard is able to be divided into three kinds as followings; (1) Turning capability standard: Estimated values in design stage are to be certified by turning circle test of the actual vessel. (2) Course keeping quality standard : Estimated values in design stage are to be certified by 10 deg. and 20 deg. zig-zag tests of the actual vessel. (3) Shortest stopping distance standard : Estimated value in design stage is to be certified by the shortest stopping distance tested by the actual vessel. In this paper, the authors verified the criteria of IMO manoeuvrability standard comparing them with the values resulted from sea trial tests of various kinds of actual vessels and examined separately the validity of all criteria of the standard.

Cycle and circle tests of balance in gain graphs: Forbidden minors and their groups

AbstractWe examine two criteria for balance of a gain graph, one based on binary cycles and one on circles. The graphs for which each criterion is valid depend on the set of allowed gain groups. The binary cycle test is invalid, except for forests, if any possible gain group has an element of odd order. Assuming all groups are allowed, or all abelian groups, or merely the cyclic group of order 3, we characterize, both constructively and by forbidden minors, the graphs for which the circle test is valid. It turns out that these three classes of groups have the same set of forbidden minors. The exact reason for the importance of the ternary cyclic group is not clear. © 2005 Wiley Periodicals, Inc. J Graph Theory

IMO 선박 조종성 기준의 계산 및 고찰에 관한 연구

대형선박의 충돌 혹은 좌초와 같은 많은 해양사고는 선박의 조종성능 부족으로 인하여 발생되고 있다. 따라서 IMO(국제해사기구)에서는 1994년 제18회 총회에서 결의서 A.751(18)로서 선박조종성에 대한 잠정기준을 채택하였고, 이 기준은 1994년 7월 1일 이후 건조된 길이100m 이상의 선박 또는 길이에 관계없이 모든 케미컬탱커 및 개스운반선에 대하여 적용된다. IMO 조종성기준은 크게 설계단계에서의 선회성능과 보침성능 및 최단정지성능으로 대별된다. 이 논문에서는 몇 척의 대형선박에 대한 최초 설계단계에서의 자료를 이용하여 조종성능에 관한 계산 및 시뮬레이션을 행하고, 계산된 결과를 모형실험 결과와 비교, 검토하였으며, IMO 조종성기준의 타당성에 관하여 검토 고찰하였다. Many sea accidents such as collisions and groundings of vessels were occurred due to the lack of sufficient manoeuvring capability of vessels. Therefore IMO adopted 'The interim standards of ship manoeuvrability by Resolution A.751(18)' and the standards have been applied to vessels of 100m or more in length and all chemical tankers and gas carriers regardless qf the length, which were constructed on or after 1 July 1994. The IMO manoeuvrability standards are divided into three kinds as bellows; (1) Turning capability standards : Estimated values in design stage are to be certified by turning circle test of the actual vessel. (2) Course keeping quality standards : Estimated values in design stage are to be certified by <TEX>$10^{\circ}\;and\;20^{\circ}$</TEX> Zig-Zag tests of the actual vessel. (3) Shortest stopping distance standards : Estimated values in design stage are to be certified by the shortest stopping distance tested by the actual vessel. In this paper, the authors computed the values of the manoeuvring standards of several vessels from their original design and compared them with those results from experiments of the model ships and also examined the values and concluded about the validity of IMO manoeuvrability standards.

A Nonlinear Mathematical Model for Ship Turning Circle Simulation in Waves

In the paper, a simplified six degrees of freedom mathematical model encompassing calm water maneuvering and traditional seakeeping theories is developed to simulate the ship turning circle test in regular waves. A coordinate system called the horizontal body axes system is used to present equations of maneuvering motion in waves. All corresponding hydrodynamic forces and coefficients for seakeeping are time varying and calculated by strip theory. For simplification, the added mass and damping coefficients are calculated using the constant draft but vary with encounter frequency. The nonlinear mathematical model developed here is successful in simulating the turning circle of a containership in sea trial conditions and can be extended to make the further simulation for the ship maneuvering under control in waves. Manuscript received at SNAME headquarters February 19, 2003; revised manuscript received January 27, 2004.

GPS-based Land Vehicle Navigation System Assisted by a Low-Cost Gyro-Free INS Using Neural Network

GPS-based land vehicle navigation systems are subject to signal fading in urban areas and require aid from other enabling sensors. A low-cost gyro-free inertial navigation system (INS) without accumulated attitude errors and complicated initializations could be an effective solution to the problem. This paper investigates a Constrained Navigation Algorithm (CNA) and the Artificial Neural Network (ANN) technique to compensate velocity output from a gyro-free INS. The vehicle's heading will be calibrated by a full circle test so that the magnetometer's bias and scale factor error could be removed. Experiments with a vehicle driven over level terrain have been conducted to assess the performance of the compensated gyro-free INS solutions. The effect of the architecture of Neural Network on prediction performance has also been discussed as well as the applicability of the proposed solution to land vehicle navigation with GPS outages.

Recursive identification procedure of the nonlinear model ship based on the turning test manoeuvring

In this paper has been carried out an identification procedure based on the adaptive backstepping design. The process depart of the experimental results obtained for a particular ship in the turning circle test. The ship's dynamics has been adjusted according to the Norrbin model being the coefficients of the nonlinear manoeuvring characteristics determined by the described procedure.

Significance of the largest scale CMB fluctuations in WMAP

We investigate anomalies reported in the cosmic microwave background maps from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite on very large angular scales and discuss possible interpretations. Three independent anomalies involve the quadrupole and octopole: (1) The cosmic quadrupole on its own is anomalous at the 1-in-20 level by being low (the cut-sky quadrupole measured by the WMAP team is more strikingly low, apparently due to a coincidence in the orientation of our Galaxy of no cosmological significance); (2) the cosmic octopole on its own is anomalous at the 1-in-20 level by being very planar; (3) the alignment between the quadrupole and octopole is anomalous at the 1-in-66 level. Although the a priori chance of all three occurring is 1 in 24000, the multitude of alternative anomalies one could have looked for dilutes the significance of such a posteriori statistics. The simplest small universe model where the universe has toroidal topology with one small dimension of order one-half the horizon scale, in the direction toward Virgo, could explain the three items above. However, we rule this model out using two topological tests: the S statistic and the matched circle test.

Loss of stereopsis with optic chiasmal lesions and stereoscopic tests as a differential test

Objective To identify and characterize the loss of stereopsis observed in patients with lesions of the optic chiasm. Study design Cross-sectional study. Participants Forty-three patients who had good visual acuity with orthophoria and without strabismologic histories were divided into two groups. Group 1 consisted of 13 patients with lesions involving the optic chiasm (regardless of their visual field loss) diagnosed by magnetic resonance imaging findings. Group 2 (control group) consisted of 30 patients who had large absolute visual field defects as a result of other causes, including 11 intracranial disorders other than optic chiasmal lesions, 11 cases of open-angle glaucoma, and 8 patients with lesions of the retina. Methods The stereoacuity and visual field in each case in group 1 (before and after surgery) and group 2 were assessed, and the results were compared. Main outcome measures Stereoacuity was assessed by the Titmus stereo test (normal value for circle, 6/9; 80 seconds of arc) and by Lang-stereotest (normal value for circle, 3/3; 350 seconds of arc). Visual field was evaluated by Goldmann and Humphrey perimetry (conventional perimetry), the starlight test (binocular visual field test), and scanning laser ophthalmoscopic microperimetry (microperimetry). Results Before surgery, 11 of 13 cases (85%) in group 1 failed stereo tests, and after surgery, 5 of 13 cases (38%) in group 1 failed stereo tests. Before surgery, four patients who failed stereo tests showed no absolute scotoma by Humphrey or Goldmann analysis; after surgery, one patient who failed stereo tests showed no absolute scotoma by Humphrey or Goldmann analysis. However, starlight testing showed complete bitemporal hemianopsia only under binocular conditions, and microperimetry demonstrated a relative bitemporal hemianopsia at the fixating point. No patient failed in the Titmus circle test, but one patient in group 2 failed the Lang test (3%). The patients with chiasmal lesions significantly lost the ability of stereopsis compared with other diseases (group 1 [before or after surgery] vs. group 2, P < 0.001, Fisher’s exact test). Conventional perimetry was unable to measure scotomas within 3° of the fixation point, which is the key area for acute foveal stereopsis, because of an attached observational mirror. Conclusions The difficulty with stereopsis in patients with lesions of the optic chiasm is most likely caused by the compression of the decussating optic nerve fibers resulting in the loss of an overlapping visual field at the fixation point. Stereo tests were demonstrated to be simple and effective adjunctive tests for suspected chiasmal compression.

Syn-folding remagnetization and the significance of the small circle test: Examples from the Vocontian trough (SE France)

We present a detailed study of paleomagnetism and anisotropy of magnetic susceptibility of two cylindrical kilometric folds. These folds are located in the footwall of the Digne thrust, from the southern border of the Vocontian trough. We sampled Bajocian–Bathonian marly limestones at four sites. Rock magnetism is consistent with a mixture of single domain and super-paramagnetic grains of magnetite (Curie temperature at 580 °C, unblocking temperature at about 450–500 °C, wasp-waisted hysteresis cycles). Gentle limbs of the two folds show a magnetic foliation of sedimentary origin parallel to the bedding, while in steepest limbs magnetic foliation is oblique to the bedding and is of tectonic origin. We found well-defined paleomagnetic directions (B components) in both folds. Fold test and small circles test are performed in order to date the acquisition of the B component. Both folds exhibit syn-folding remagnetization when using fold test. Small circle tests give contrasted results. Untilting paths of B components follow two distinct small circles at Vaumeilh, which is not expected if the magnetization is related to cylindrical folding. We propose that a complex strain history is likely the cause of this unexpected behavior. By contrast, only one small circle is observed when untilting B components of Bayon fold. The overlapping paths of B components define a strip of uncertainty, which is compared to the range of expected inclinations for stable Eurasia. This allows to date the remagnetization from Tertiary at Bayon fold.

The effects of creative problem solving training on creativity, cognitive type and R&amp;D performance

The effects of Creative Problem Solving (CPS) training on creativity, cognitive type, and R&amp;D performance were investigated with 106 R&amp;D workers of a large government–owned manufacturing company in Taiwan. Seventy–one of them volunteered to participate in the CPS training and were divided into three groups. Each group received 12 hours of CPS training and two follow–up training sessions over a one–year long period in a time–series design. The ‘Circle Test of the Torrance Test of Creative Thinking’, and the ‘Myers–Briggs Type Indicator’ were administered before and after the CPS training. R&amp;D performance averaged over the past three years before the CPS training and one year after the pretest were obtained from the company. Results showed that participant’s scores on fluency and flexibility of ideas were higher after the CPS training. There was also an increase in the number of persons being classified as extrovert or feeling type of cognition. In terms of R&amp;D performance, the participants’ number of co–authored service projects increased significantly from pretest to posttest, whereas no such change was observed among those 35 R&amp;D workers who did not participated in the CPS.

Distance stereopsis as a screening device.

To determine the efficacy of distance stereotesting as a screening device. Distance stereoacuity using the global Random Dot and contour Circle test of the Mentor BVAT II-SG computerized testing system was measured for 216 patients, ages 6 to 18 years, before the clinical examination. Patients were classified into pass/fail groups in the areas of refractive error change (REC), ocular deviation (DEV), visual acuity (VA), and all three together (EXAM). Legitimate cutoff scores were obtained when patients were classified as 'pass' as follows: REC if the change was 0.50 D or less in sphere or cylinder relative to the habitual correction or to emmetropia if no habitual correction; DEV if there was no heterophoria or strabismus at distance (criteria of heterophoria of < 6 prism diopters and heterophorias of any magnitude were also tested); VA if the acuity at distance was better than or equal to 20/25 in the poorer eye and better than or equal to 20/20 in the better eye; EXAM if they were pass in REC, DEV, and VA. Optimal pass/fail cutoff values for the stereopsis measurements were determined by finding the maximum chi2 value from contingency tables constructed using pass/fail levels for the screening test at each of the observed levels. The pass rates for REC, DEV, VA, and EXAM were 45%, 72%, 42%, and 24%, respectively. Patients passed the BVAT at the analytically determined optimal cutoff values of less than or equal to 120 sec arc for global and less than or equal to 30 sec arc for contour stereopsis. The sensitivity and specificity for global stereopsis were 0.90 and 0.40 for REC, 0.89 and 0.30 for DEV, 0.93 and 0.51 for VA, and 0.87 and 0.63 for EXAM. For contour stereopsis, the corresponding values were 0.85 and 0.42, 0.89 and 0.34, 0.91 and 0.53, and 0.84 and 0.62. Distance stereotesting is highly sensitive to small refractive error changes, heterophorias and strabismus, visual acuities < 20/25, or any of the three. Global stereopsis is only slightly better than contour stereopsis at classifying patients. Distance stereotesting has potential as an effective screening test.

Creative Thinking Ability, Cognitive Type and R&amp;D Performance

The purpose of this study was to investigate the contributions of creative thinking ability and cognitive type to research and development (R&amp;D) performance. One hundred and six researchers in an R&amp;D institute of a petroleum company in Taiwan were given the Circle Test of the Torrance Test of Creative Thinking and Myers‐Briggs Type Indicator. Their R&amp;D performance was measured in terms of assigned technical reports, completed service projects, published papers, and a supervisor’s performance rating. Results showed that there was a low but positive correlation between creativity and the first‐authored paper and the technical report. The cognitive type was on the other hand associated with the performance rating and the first‐authored service project assignment. Implications for R&amp;D management are discussed.

The circles of time

The temporal aspects of strategy and decision making have not, until recently, been accorded the importance they deserve. This paper describes a study undertaken to measure the temporal perception of people in an organization. An instrument was devised which the authors have called “the circle test” which measures subjects’ temporal relatedness and temporal dominance ‐ how people perceive the relationship between their past, present and future. Since the size of the organization studied is small, the research took the form of an exploratory study only, but the results of the research indicate that the use of the circle test can demonstrate differences in temporal perception between the sexes and between different age groups. Differences in temporal perception between people at different responsibility levels in the organisation is also suggested.

Turning Controller for Ships

The paper describes the design of a new type of turning controller for ships, where a feedforward model of the ship steering dynamics is introduced. The straightforward concepts of Kalman filtering and Linear-Quadratic control are used in combination with the feedforward model. The use of a ship steering model and an appropriate scaling of the parameters with respect to both ship size and ship's velocity gives a significant advantage compared to normal PID-type controllers. The total design is unified and the same ship steering model is used in all parts of the turning controller. The parameter setting is extremely simplified, since only three parameters have to be entered for a specific ship. The gain and time constant of the ship steering model are determined from a turning circle test, and then also the ship length has to be entered. The ship steering model is used in the Kalman filter, in the design of the Linear-Quadratic controller and in the feedforward model. The ship length is used in order to obtain an appropriate scaling of parameters. This means that no actual tuning of parameters is required, which results in a significant reduction of the start-up time when installing an autopilot with this type of turning controller combined with an adaptive steady-state coursekeeping regulator. The use of velocity scaling gives an excellent performance from ship speeds of about 10 knots, and quite an acceptable behaviour from 5 knots. Simulation results with a patrol boat (length 35 m) and a ferry (length 120 m) are presented in the paper.

Predictive Validities of Clinical and Actuarial Scores of the Gesell Incomplete Man Test

The predictive validities of clinical and actuarial scores of the Gesell Incomplete Man Test were investigated to determine their relationships with selected intelligence, achievement, and creativity measures over a 5-yr. interval. Criterion measures included the Lorge-Thorndike Intelligence Test, Goodenough-Harris Figure Drawing Test, Iowa Tests of Basic Skills, and Torrance Circle Test. Correlational analysis indicated that each scoring method yielded generally similar relationships with corresponding criterion measures. Except for the relationships with intellectual criteria, however, the predictive value of the Incomplete Man was negligible for these boys and girls of elementary-school age (N = 61).

Total and Component Actuarial Scores of the Gesell Copy Form Test as Predictors of Achievement, Intelligence, and Creativity Measures

Abstract The predictive validities of the five component actuarial scores of the Gesell Copy Form Test—Basic Form, Proportion, Corners and Closures, Size, and Size Range—were investigated to determine whether any sub-scores were able to predict selected achievement, intelligence, and creativity measures more effectively than the Copy Form Total actuarial score over a five-year interval. Criterion measures included the Iowa Tests of Basic Skills, Lorge-Thorndike Intelligence Test, Goodenough-Harris Figure Drawing Test, and Torrance Circle Test. Correlational analysis revealed that the Proportion and Corners and Closures scores yielded a greater number of significant correlation coefficients than did the Copy Form Total actuarial score with achievement scores of the male and female elementary students (N = 60) included in the sample.