• Title/Summary/Keyword: Spatial orientation

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The Effect of Cr Dosage on FePt Nanoparticle Formation

  • Won, C.;Keavney, D.J.;Divan, R.;Bader, S.D.
    • Journal of Magnetics
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    • v.11 no.4
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    • pp.182-188
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    • 2006
  • The search for high-density recording materials has been one of most active and vigorous field in the field of magnetism. $FePt-L1_{0}$ nanoparticle has emerged as a potential candidate because of its high anisotropy. In this paper, we provide an overview of recent work at Argonne National Laboratory that contributes to the ongoing dialogue concerning the relation between structure and properties of the FePt nanoparticle system. In particular we discuss the ability to control structure and properties via dosing with Cr. Cr-dosed FePt films were grown via molecular beam epitaxy and annealed at $550^{\circ}C$ in an ultrahigh vacuum chamber, and were studied with the surface magneto-optic Kerr effect (SMOKE), scanning electron microscopy (SEM) and x-ray magnetic circular dichroism (XMCD). We found that small dosage of Cr helps to generate $L1_{0}$ phase FePt magnetic nanoparticles with small size, defined shape and regular spatial distribution on MgO (001) substrate. The nanostructures are ferromagnetic with high magnetic coercivity (${\sim}0.9T$) and magnetic easy axis in the desired out-of-plane orientation. We also show that controlling the lateral region where nanostructures exist is possible via artificial patterning with Cr.

Self-Care in Elders with Dementia: A Concept Analysis

  • Yeom Hye-A
    • Journal of Korean Academy of Nursing
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    • v.34 no.8
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    • pp.1402-1408
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    • 2004
  • Purpose: The purpose of this study was to analyze the concept of self-care in elders with dementia through a review of nursing literature and to provide more understanding of the definition and perspectives of the concept of self-care notion in elders with dementia. Methods: The technique developed by Walker and Avant was used as a guide in analyzing the concept of self-care. Results: Attributes of self-care in dementia may include a single or group of actions needed for sustaining life, a personal effort to maintain functional independence while minimizing other's assistance, an outcome behavior from the person's interaction with inter-personal and/or contextual environment, and a functional ability that may decline in parallel to cognitive impairment. Antecedents of self-care in dementia may include at least presence of a certain degree of cognitive appraisal for the self-care needs, self-willingness for the self-care action, spatial and visual orientation, cultural pre-conception of the self-care behavior, presence of environmental context/equipment available for self-care, and sufficient time available. The consequences may include sustaining of life, feel of satisfaction, achieving independence, extended life expectancy, increased self-confidence, decreased caregiver distress and/or burden, savings in health care costs. Discussion: Defining attributes and antecedents and consequences of self-care in dementia identified in this study provided empirical ground of a middle-range theory of self-care for a clinical population with dementia and generated possible hypotheses to be tested in future studies.

Analysis and Classification of Broadband Acoustic Echoes from Individual Live Fish using the Pulse Compression Technique (펄스압축기법을 이용한 활어 개체어에 대한 광대역 음향산란신호의 분석 및 식별)

  • Lee, Dae-Jae;Kang, Hee-Young;Kwak, Min Son
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.2
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    • pp.207-220
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    • 2015
  • This study identified the species-specific, frequency-dependent characteristics of broadband acoustic scattering that facilitate classifying fish species using the pulse compression (PC) technique. Controlled acoustic scattering laboratory experiments were conducted with nine commercially important fish species using linear chirp signals (95-220 kHz) over an orientation angle range of ${\pm}45^{\circ}$ in the dorsal plane at approximately $1^{\circ}$ increments. The results suggest that the angular-dependent characteristics of the broadband echoes and the frequency-dependent variability in target strength (TS) were useful for inferring the fish species of interest. The scattering patterns in the compressed pulse output were extremely complex due to morphological differences among fish species, but the x-ray images strongly suggested that spatial separation correlated well with scattering for the head, skeleton, bone, otoliths, and swim bladder within each specimen.

Quincunx Sampling Method For Improvement of Double-Density Wavelet Transformation (이중 밀도 웨이브렛 변환의 성능 향상을 위한 Quincunx 표본화 기법)

  • Lim, Joong Hee;Shin, Jong Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.1
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    • pp.171-181
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    • 2012
  • This paper introduces the double-density discrete wavelet transform(DWT) using quincunx sampling, which is a DWT that combines the double-density DWT and quincunx sampling method, each of which has its own characteristics and advantages. The double-density DWT is an improvement upon the critically sampled DWT with important additional properties: Firstly, It employs one scaling function and two distinct wavelets, which are designed to be offset from one another by one half. Secondly, the double-density DWT is overcomplete by a factor of two, and Finally, it is nearly shift-invariant. In two dimensions, this transform outperforms the standard DWT in terms of denoising; however, there is room for improvement because not all of the wavelets are directional. That is, although the double-density DWT utilizes more wavelets, some lack a dominant spatial orientation, which prevents them from being able to isolate those directions. A solution to this problem is a quincunx sampling method. The quincunx lattice is a sampling method in image processing. It treats the different directions more homogeneously than the separable two dimensional schemes. Proposed wavelet transformation can generate sub-images of multiple degrees rotated versions. Therefore, This method services good performance in image processing fields.

The Three Directional Separable Processing Method for Double-Density Wavelet Transformation Improvement (이중 밀도 웨이브렛 변환의 성능 향상을 위한 3방향 분리 처리 기법)

  • Shin, Jong Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.2
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    • pp.131-143
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    • 2012
  • This paper introduces the double-density discrete wavelet transform using 3 direction separable processing method, which is a discrete wavelet transform that combines the double-density discrete wavelet transform and quincunx sampling method, each of which has its own characteristics and advantages. The double-density discrete wavelet transform is nearly shift-invariant. But there is room for improvement because not all of the wavelets are directional. That is, although the double-density DWT utilizes more wavelets, some lack a dominant spatial orientation, which prevents them from being able to isolate those directions. The dual-tree discrete wavelet transform has a more computationally efficient approach to shift invariance. Also, the dual-tree discrete wavelet transform gives much better directional selectivity when filtering multidimensional signals. But this transformation has more cost complexity Because it needs eight digital filters. Therefor, we need to hybrid transform which has the more directional selection and the lower cost complexity. A solution to this problem is a the double-density discrete wavelet transform using 3 direction separable processing method. The proposed wavelet transformation services good performance in image and video processing fields.

Modeling Methods for SPOT-5 HRG Stereo Pair Images (SPOT-5(HRG) 입체위성영상의 3차원 모델링 기법 연구)

  • 최선용;신대식;이용웅
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.21 no.3
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    • pp.255-260
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    • 2003
  • In this paper, we generate the 3D geometric sensor model of SPOT-5 HRG stereo images which are processed in Supermode and have 2.5m ground spatial resolution, and calculate the RPC(Rational Polynomial Coefficients) for acquisition of topographic information using the exterior orientation parameters which are determined in the 3D geometric sensor modelling process. It is shown that SPOT-5 images can be modelled with me 3.3m accuracy by the bundle adjustment method used to model the existing SPOT series. Considering the accuracy of RPC's results with rmse 0.03m accuracy, the RPC model can replace the sensor model, if we emphasize the simplification and the cost.

Simulation and Three-dimensional Animation of Skipjack Behavior as Capture Process during Purse Seining

  • Kim, Yong-Hae;Park, Myeong-Chul;Ha, Suk-Wun
    • Fisheries and Aquatic Sciences
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    • v.11 no.2
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    • pp.113-123
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    • 2008
  • We modeled fish school movements as a capture process in relation to the purse seine method using the three steps of the stimulus-response process (i.e., input stimuli, central decision-making and output reaction). Input stimuli of the model were categorized as either physical stimuli such as visual stimulus, sound stimulus, water flow, and weather or as biological stimuli such as species and size, swimming performance, sensual sensitivity, and presence of prey or predators. The output process determining the spatial orientation of the fish school for 3-D movements was based on swimming speed and angular change in the fish response, and these movements were animated as the relative geometry between the fish school and the purse seine. Simulations were carried out for skipjack tuna (Katsuwonus pelamis) schools reacting to a pelagic purse seine in the southwest Pacific Ocean. Simulation results showed that escape ratios varied from 20 to 70% by the relevant ranges in the stimulus-response thresholds, swimming speeds, and angular changes of fish schools were similar to those observed in the field. Therefore, with knowledge of relevant parameters, this model can be used to predict capture and escape probabilities of purse seine operations for different fish species or conditions.

Ferroelectric Domans in $BaTiO_3$ ($BaTiO_3$의 강유전성 분역)

  • 박봉모;정수진
    • Journal of the Korean Ceramic Society
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    • v.33 no.1
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    • pp.56-64
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    • 1996
  • A large amount of papers about the cubic-to-tetragonal phase transition the ferroelectric domain structures of the BaTiO3 were already reported but there exist still some needs to observe the domain behaviors directly. In this study the domain structures of the tinned plates prepared from ta single crystal grown by the TSSG technique were observed using a polarizing microscope TE and X-ray topography. The spatial relation be-tween the orientation states of domains was investigated and the effects of external stresses and electric fields on the behaviors of ferroelectric and ferroelastic domains were studied. All the 90$^{\circ}$walls cut off in the crystal are the wedge shaped lamellar domains and all the straight boundaries in the observed domain patte군 can be interpreted as the head-to-tail 90$^{\circ}$walls. The irregular overlapped boundaries commonly observed by using a polarizing microscope and X-ray topography are complex combinations of well-known 90$^{\circ}$walls and are domain walls were predominant and were stabilized after surface polishing. In the paraelectric phase region the domain walls vanished but the residual surface strain patterns could be seen at the same positions of the stabilized 90$^{\circ}$a-a walls in the tetragonal phase region, These stabilized walls resulted from the surface strain had a memory effect in domain formation during the repeated phase transitions and could notr be affected by an external electtric field.

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Bone Density Spatial Distribution of Radiation Dose Measurement (양방사선 골밀도 측정 장치의 공간산란선량분포측정)

  • Kim, Seon-Chil;Won, Do-Yeon;Park, Chang-Hee;Dong, Kyung-Rae
    • Korean Journal of Digital Imaging in Medicine
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    • v.13 no.2
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    • pp.59-62
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    • 2011
  • In this experiment, how DEXA(Dual-energy X-ray Absorptiometry) bone mineral density was measured using the equipment. In order to maintain the same measurement conditions, bone mineral density measurements of 10 cm thick phantom, with an actual patient at a point when examining the same conditions(100 kVp, 1 mA) and then out to the five doses of radiation and its average was calculated by dividing measured. X-ray dose rate measured at the Research Institute, Sword of the gamma survey meters calibrated MEDCOM Ltd. (Inspector GM counter tube) was used, calibration factor is 1.15. On a horizontal plane around the patient, depending on the distance was significantly reduced dose rate. In addition, orientation $0^{\circ}$ head end was higher in the direction of the highest dose rate, $0^{\circ}$ $180^{\circ}$ direction from the direction towards the higher dose rate reduced to some extent in the direction of all the $120^{\circ}$ were able to identify.

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Digital Image Processing Using Non-separable High Density Discrete Wavelet Transformation (비분리 고밀도 이산 웨이브렛 변환을 이용한 디지털 영상처리)

  • Shin, Jong Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.1
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    • pp.165-176
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    • 2013
  • This paper introduces the high density discrete wavelet transform using quincunx sampling, which is a discrete wavelet transformation that combines the high density discrete transformation and non-separable processing method, each of which has its own characteristics and advantages. The high density discrete wavelet transformation is one that expands an N point signal to M transform coefficients with M > N. The high density discrete wavelet transformation is a new set of dyadic wavelet transformation with two generators. The construction provides a higher sampling in both time and frequency. This new transform is approximately shift-invariant and has intermediate scales. In two dimensions, this transform outperforms the standard discrete wavelet transformation in terms of shift-invariant. Although the transformation utilizes more wavelets, sampling rates are high costs and some lack a dominant spatial orientation, which prevents them from being able to isolate those directions. A solution to this problem is a non separable method. The quincunx lattice is a non-separable sampling method in image processing. It treats the different directions more homogeneously than the separable two dimensional schemes. Proposed wavelet transformation can generate sub-images of multiple degrees rotated versions. Therefore, This method services good performance in image processing fields.