Degrees Of Freedom Values Research Articles

Factors Influencing Tourists’ Decision In VisitingTourist Areas

This study aims to determine the price, location, and facilities jointly affect the decision of tourists in visiting the tourist attraction Park Pusuk Sembalun. This type of research is quantitative research with descriptive correlation method. The sample in this study were 40 samples in the tourist attraction of Puskesmas Sembalun Park in Sembalun Bumbung Village, Sembalun Subdistrict. Methods of data collection using observation, interviews, documentation and questionnaires. Data analysis techniques used are test instruments (validity and reliability), multiple linear regression analysis, classical assumption tests and hypothesis testing. From the results of simultaneous testing shows the variables of factors that influence the visiting of tourists (price, location and facilities) together have a significant influence on the decision of tourists in visiting the tourist attraction park pusuk sembalun. This is evidenced by the acquisition of a calculated F value of 10.345 with a significant level of 0,000 while the degree of freedom value is 3 and 36, so that in F table the value is 2.87. Thus the F value counts 10.345 ˃ F table value (significant). While the partial testing of the price variable has an influence on tourist visiting decisions as much as 0.493 with a t-count of 0.05 and a significant level of 0.002. while location variables and facilities do not have a significant effect. This is evidenced by the value of the location variable of 0.143 with a t-count of 0.05 and a significant level of 0.357 and a variable value of 0.242 with a t-count of 0.05 and a significant level of 0.067.

Housing design during COVID-19: effects of psychological states on Japanese architecture students

ABSTRACT During the coronavirus disease (COVID-19) pandemic, people worldwide were psychologically affected by being limited to mostly indoor, at-home activities. This study sought to clarify how COVID-19-related psychological states and anxiety affect changes in designs and perceptions of living environments. Hence, this study assigned a housing design task to architecture students – considerations included windows (window-to-wall ratio), lighting plan, color plan, and floor area – and conducted a survey regarding the related deliverables. The results showed that anxiety about going out affected perceptions of openness and publicity, whereas fear of COVID-19 infection affected impressions of space, brightness, and naturalness. These psychological effects are reflected in the total floor area, window area, and color planning. These effects reveal how the psychological state of the designer affects the spatial elements in architectural design. Abbreviations: SD method - Semantic differential method SD - Standard deviation WWR - Window-to-wall ratio Df value – Degrees of freedom value

Vascular Analysis of Radial Artery Perforator Flaps.

Background:Radial forearm free flap with all its present day modifications is the workhorse of soft tissue reconstruction in head & neck. Although there are several advantages, it requires the sacrifice of a major artery of forearm. There are several modifications of harvesting a forearm flap based on perforator principles. A clear understanding of vascular anatomy of individual perforators relative to its vascular territory & flow characteristics is essential for both flap harvest & design. The purpose of this cadaveric observational anatomical study was to determine the location, size & vascular territory of the radial artery cutaneous perforators.Materials and Methods:12 fresh human cadavers & 24 cadaveric forearms were dissected to determine the total number, location, size & vascular territory of radial artery adipo-fascio cutaneous perforator. The cutaneous territory of distally dominant perforators was analyzed using methylene blue injections & three-dimensional computed tomographic angiogram.Results:In the 12 fresh human cadavers & 24 forearm specimens, a total of 222 perforators were dissected for an average of 18.5 radial artery perforators per forearm. Of the total 222 perforators dissected 118 were smaller than 0.5mm in diameter (53.15%) these were not clinically significant. 104 perforators were greater than 0.5mm in diameter (46.84%) these were clinically significant. Of the 222 radial artery perforators dissected, 127 perforators (57.20%) were radially distributed & 95 perforators (42.79%) had ulnar distribution. A total of 90 perforators (40.54%) were identified on distal side (Radial styloid) & 132 perforators (59.45%) were identified on proximal side (Lateral epicondyle). Mean number of perforators on radial side was 10.6 & 7.9 on ulnar side, a comparison of both using student t paired test gives a P value of 0.006, which was statistically significant. Comparison of mean number of perforators on the distal side was 7.5 & proximal side was 11.0, Student Paired t test gives a P value of 0.003, which was statistically significant. Comparison of mean Diameter of perforators between the Distal side (1.11) & Proximal side (0.86) using Student Paired t test gives a P value of 0.01 which was statistically significant. A chi square test was done to compare mean diameter of perforators on distal side, which were more than 1mm (80%) & less than 1mm (20%) & on proximal side more than 1mm (35.6%) & less than 1mm (64.4%). Chi square value of 42.406 was obtained, degree of freedom value was 1& P value of <0.001 was achieved which was found to be highly significant. Methylene blue injections into the proximal part of radial artery demonstrated clusters both in proximal & distal forearm & also cutaneous territory of flap. Three- dimensional computed tomographic angiography reveals a network of linking vessels found to communicate between adjacent perforators & running parallel to radial artery. Large network of linking vessels could be found between fascia & dermis, which also explains the ability to harvest forearm flap at the supra-fascial level.Conclusion:Increase in knowledge of vascular territory of radial artery perforators with regards to numbers, size, location, and cutaneous territory can lead to expanded use of radial forearm flap based on either distal or proximal perforator alone, without sacrificing the radial artery.

Adipo Fascio Cutaneous Perforator Based, Shape Modified Radial Forearm Flap: Vascular Analysis of Perforators &amp;amp; Its Clinical Applications in Head &amp;amp; Neck Reconstruction

Resume of the study & Background: Radial forearm free flap with all its present day modifications is the workhorse of soft tissue reconstruction. Although there are several advantages, it requires sacrifice of a major artery of forearm. Several modifications are described in harvesting a forearm flap. In order to achieve a reliable, safe flap harvest & design one must have a very clear understanding of radial artery perforators, relative to its distribution, territory & flow. The purpose of this study is to determine the location, size & vascular territory of the radial artery cutaneous perforators & to demonstrate application of shape modification of radial forearm free flap based on its distal & proximal perforators in various head & neck defects. Materials & Methods: Anatomical Study: 12 fresh human cadavers & 24 cadaveric forearms were dissected to determine the number, location, size & vascular territory of radial artery perforator. The cutaneous territory of distally dominant perforators was analyzed using methylene blue injections & three-dimensional computed tomographic angiogram to determine the vascular network. Clinical Study: 15 patients with various head neck defects following oncological resections were reconstructed with shape modified adipo-fascio cutaneous free forearm flap. All these patients were prospectively followed for donor site healing, motor & sensory nerve deficit, function & quality of life questioner for donor site assessment. Results: 12 fresh human cadavers & 24 cadaveric forearms were dissected, and a total of 222 perforators were dissected for an average of 18.5 perforators per forearm. 118 were smaller than 0.5 mm in diameter (53.15%) & were not clinically significant. 104 perforators were greater than 0.5 mm in diameter (46.84%) & were clinically significant. 127 perforators (57.20%) were radially distributed & 95 perforators (42.79%) had ulnar distribution. 90 perforators (40.54%) were identified on distal side (Radial styloid) & 132 perforators (59.45%) were identified on proximal side (Lateral epicondyle). Mean number of perforators, on radial side was 10.6 & 7.9 on ulnar side; comparison of both using student t paired test gives a P value of 0.006, which is significant. Comparison of mean number of perforators on the distal side was 7.5 & proximal side was 11.0; Student Paired t test gives a P value of 0.003, which was statistically significant. Comparison of mean diameter of perforators on Distal side (1.11) & Proximal side (0.86), side using Student Paired t test gives a P value of 0.01 which was statistically significant. A chi square test was done to compare mean diameter of perforators on distal side, which was more than 1 mm (80%) & less than 1 mm (20%) & on proximal side more than 1 mm (35.6%) & less than 1 mm (64.4%). Chi square value of 42.406 was obtained, degree of freedom value was 1 & P value of <0.001 was achieved which was found to be highly significant. Methylene blue injections demonstrated clusters both in proximal & distal forearm & also marked the cutaneous territory of flap. Three-dimensional computed tomographic angiography reveals a network of linking vessels found to communicate between adjacent perforators & running parallel to radial artery. A total of 15 patients were reconstructed with shape modified radial forearm flap following oncologic resections. Wound healing in all 15 patients was good, with scar assessment faring better than traditional radial forearm flap. There was no sensory or motor nerve deficit. Although pedicle length was comparatively shorter in shape-modified flap, there was no problem in anastomosing to neck vessels. Conclusion: Increase in knowledge of vascular territory of radial artery perforators with regards to numbers, size, location, & cutaneous territory can lead to expanded use of radial forearm flap based on either distal or proximal perforator alone. Shape modified technique for harvesting radial forearm flap allows primary closure of donor site. Donor site is better healed and shows a predicted pattern, which is functionally and aesthetically good.

THE EFFECT OF USING GRAPHIC ORGANIZER TO STUDENTS’ WRITING ABILITY

This study aimed at investigating the effect of using Graphic Organizer to students’ writing ability. This research was designed as a quasi-experimental research. The population of this research were all eleventh grade students at SMA N 1 Bengkulu Utara. The sample of this research was chosen by purposive sampling technique, so there were two science classes which consist of 52 students as the sample. Pre-test and post-test were involved as the instrument of this research. The first group was as experimental group taught by graphic organizer technique and the second group was as control group taught by conventional technique. The pre test was given to both experimental and control groups at the beginning, treatments were given in six meetings, and post test given at the end of the term. The data were analyzed by using t-test formula. From the calculation, the researcher found that the t-test value was 5.00, the degree of freedom value was 50, and the t-table was 3.49. Since t-test was higher than t-table (5.00 &gt; 3.49), it meant that alternative hypothesis (H1) was accepted. Thus, it could be concluded that the use of graphic organizer was effective to students’ writing ability in term of content, organization, and language use.

Achievable DoF-Delay Trade-Offs for the $K$ -user MIMO Interference Channel With Delayed CSIT

The degrees of freedom (DoF) of the $K$-user multiple-input multiple-output (MIMO) interference channel are studied when perfect, but delayed channel state information is available at the transmitter side (delayed CSIT). Recent works have proposed schemes that achieve increasing DoF values, but at the cost of long communication delays. This work proposes three linear precoding strategies, formulated in such a way that the achievable DoF can be derived as a function of the transmission delay, thus elucidating its achievable DoF-delay trade-off. All strategies are based on the concept of interference alignment, and built upon three main ingredients: delayed CSIT precoding, user scheduling, and redundancy transmission. In this respect, the interference alignment is realized by exploiting delayed CSIT in order to align the interference at the non-intended receivers along the space-time domain. Finally, the latter part of this work settles that all the proposed strategies work also for constant channels, except for SISO. In such a case, the schemes can be made feasible by resorting to asymmetric complex signaling concepts. This conclusion removes the time-varying channels assumption unnecessarily common along all the literature on delayed CSIT.

Ergodic interference alignment for MIMO interference system with variable channel

The authors pay focus on the K user multiple-input multiple-output (MIMO) Gaussian interference channel (IC) with M transmitting antennas and N receiving antennas, in which min (M, N)/max (M, N) ⩾ (K−1)/[K (K−2)] and K > 3. The channel coefficients are variable, time varying or frequency selectively drawn from a continuous distribution. Based on ergodic interference alignment (IA), an achievable scheme was proposed to achieve a total of KMN/(M + N) degrees of freedom (DoF). The ergodic IA scheme can reach the optimal DoF value with simply linear beamforming and finite symbols. Furthermore, the achievable rate of the ergodic IA scheme was derived at any signal-to-noise ratio (SNR). With numerical simulation, the performance of the proposed scheme is evaluated.

Degrees of Freedom of Rank-Deficient MIMO Interference Channels

We characterize the degrees of freedom (DoF) of multiple-input and multiple-output (MIMO) interference channels with rank-deficient channel matrices. For the two-user rank-deficient MIMO interference channel, we provide a tight outer bound to show that the previously known achievable DoF in the symmetric case is optimal and generalize the result to fully asymmetric settings. For the K-user rank-deficient interference channel, we improve the previously known achievable DoF and provide a tight outer bound to establish optimality in symmetric settings. In particular, we show that for the K-user rank-deficient interference channel, when all nodes have M antennas, all direct channels have rank D 0 , all cross channels are of rank D, and the channels are otherwise generic, the optimal DoF value per user is min(D 0 , M - (min(M, (K - 1)D)/2)). Notably for interference channels, the rank-deficiency of direct channels does not help and the rank deficiency of cross-channels does not hurt. The main technical challenge is to account for the spatial dependences introduced by rank deficiencies in the interference alignment schemes that typically rely on the independence of channel coefficients.

Design Plant-wide Control to Waste Heat Recovery Generation on Cement Industry Based HYSYS

Abstract Waste heat recovery generation (WHRG) is a power plant system that utilizes the flue gas to generate an electrical power in cement industry. This plant has various unit operations, such as economizer, evaporator, superheater, steam drum, and turbine. To design WHRG plant, steam drum needs to be controlled in the first place, for the reason that this unit operation will affect steam quality utilized to drive the turbine. There are three finest control elements which can be applied on steam drum; they are level control, pressure control, and mass flow rate control. The control structure on steam drum has deficiency on overcoming the load change value. To handle this problem, WHRG plant needs the other control structure. Plantwide control (PWC) is one of control method to handle the default load changes value. There are two kinds of design methods part based on PWC, the first part is top-down and the second part is bottom-up. Top-down part is a method used to optimize a particular process by determining the advantageous function, while bottom-up part is a method used to maintain the stability rate of the system. Since this study was aimed to control WHRG plant by considering the stability rate, bottom-up part was utilized. The stages used in designing the research based on bottom-up part are determining the operational objectives and limitations, analyzing the degree of freedom in the form of degree of freedom value used to calculate the total of manipulated variable (MV), determining variable process needs controlling, determining the manipulator of production rate, determining the structure of regulatory control layer, determining the adjustment of controller based on Relative Gain Array (RGA) method, and administering open loop test derived from the resulted system's responses. Based on PWC method, there are three kinds of control structures; they are boiler follow (BFC), turbines follow (TFC), and coordinate controller (CC). The output response resulted by this simulation show that CC is the most precise control structure to handle the load changes on WHRG plant. It can analyze with low value of IAE, settling time, and maximum overshoot of the control result. The IAE value of CC is 857.3439, BFC = 1182.895, while TFC = 887.1246. CC control structure produces IAE better than BFC and TFC. Hence, the precise control structure for WHRG plant is CC.

Degrees of freedom for MIMO interference broadcast channels

Multiple-input multiple-output (MIMO) interference broadcast channel (IBC) plays an important role in the modern wireless communications. The upper bound of degrees of freedom (DoF) and its Corresponding achievable schemes was investigated. However, all the achievable schemes require perfect channel state information at transmitters (CSIT). In absence of CSIT, the DoF value is still unknown. This article mainly focuses on the G-cell K-user MIMO IBC, where there are M antennas at each transmitter and N antennas at each receiver. The transmitters only know channel coherence time internals rather than the values of channel coefficients. The users in the same cell are assumed to be able to share the channel information. Based on a heterogeneous semi-staggered block fading model, a blind interference alignment (IA) scheme was proposed for this scenario. It is shown that when R≥1/(G-1) and R = min(M,KN)/max(M,KN), a total of GKMN/(M + KN) DoF can be achieved. The inner bound is same with the decomposition DoF upper bound. Since the complexity is an important performance index to evaluate the achievable scheme, the quantitative analysis for the complexity is presented.

The Degrees of Freedom for MIMO Interference Broadcast Channels with no CSIT

Multiple-input multiple-output (MIMO) interference broadcast channel (IBC) plays an important role in the modern wireless communications. The upper bound of degree of freedom (DoF) and corresponding achievable schemes have been investigated. However, all the achievable schemes require perfect channel state information at transmitters (CSIT). In the absence of CSIT, the DoF value is still unknown. This paper mainly focuses on theG-cellK-user MIMO IBC, where there areMantennas at each transmitter andNantennas at each receiver. The transmitters only know channel coherent time internals rather than the values of channel coefficients. The users in the same cell are assumed to be able to share the channel information. Based on a heterogeneous block fading model, a blind interference alignment (IA) scheme is proposed for this scenario. We show that when and , then a total of degrees of freedom (DoF) can be achieved. The inner bound is same with the decomposition DoF upper bound.

Subspace Alignment Chains and the Degrees of Freedom of the Three-User MIMO Interference Channel

We show that the three-user M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> × M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> Multiple-Input Multiple-Output (MIMO) interference channel where each transmitter is equipped with M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> antennas and each receiver is equipped with M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> antennas has (M) d(M, N) = <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Δ</sup> min (M/2-1/κ, N/2+1/κ) degrees of freedom (DoF) normalized by time, frequency, and space dimensions, where = <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Δ</sup> min(M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> , M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> ), N = <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Δ</sup> max(M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> , M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> ), κ = <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Δ</sup> ⌈M/N-M⌉. While the DoF outer bound of d(M, N) is established for every M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> , M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> value, the achievability of d(M, N) DoF is established in general subject to a normalization with respect to spatial extensions, i.e., the scaling of the number of antennas at all nodes. In particular, we show that qd(M, N) DoF are achievable for the three-user qMT × qMR MIMO interference channel, for some positive integer q, which may be seen as a spatial extension factor. q is the scaling factor needed to make the value qd(M, N) an integer. Given spatial extensions, the achievability relies only on linear beamforming based interference alignment schemes and requires neither channel extensions nor channel variations in time or frequency. In the absence of spatial extensions, it is shown through examples how essentially the same interference alignment scheme may be applied over time-extensions over either constant or time-varying channels. The central new insight to emerge from this paper is the notion of subspace alignment chains as the DoF bottlenecks. The subspace alignment chains are instrumental both in identifying the extra dimensions to be provided by a genie to a receiver for the DoF outer bound, as well as in the construction of the optimal interference alignment schemes. The DoF value d(M, N) is a piecewise linear function of M, N, with either M or N being the bottleneck within each linear segment, whereas the other value contains some redundancy, i.e., it can be reduced without reducing the DoF. The corner points of these piecewise linear segments correspond to two sets, A={1/2, 2/3, 3/4, ...}and B={1/3, 3/5, 5/7, ...}. The set A contains all those values of M/N and only those values of M/N for which there is redundancy in both M and N, i.e., either can be reduced without reducing the DoF. The set B contains all those values of M/N and only those values of M/N for which there is no redundancy in either M or N, i.e., neither can be reduced without reducing the DoF. Because A and B represent settings with maximum and minimum redundancy, essentially they are the basis for the DoF outer bounds and inner bounds, respectively. Our results settle the question of feasibility of linear interference alignment, introduced previously by Cenk et al., for the three-user M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> × M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> MIMO interference channel, completely for all values of M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> , M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> . In particular, we show that the linear interference alignment problem (M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> × M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> , d) <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> (as defined in previous paper by Cenk et al.) is feasible if and only if d ≤ d(M, N). With the exception of the values M/N ∈ B, and only with that exception, we show that for every M/N value there are proper systems (as defined by Cenk et al.) that are not feasible. Evidently the redundancy contained in all other values of M/N manifests itself as superfluous variables that are not discounted in the definition of proper systems, thus creating a discrepancy between proper and feasible systems. Our results show that M/N ∈ A are the only values for which there is no DoF benefit of joint processing among co-located antennas at the transmitters or receivers. This may also be seen as a consequence of the maximum redundancy in the M/N ∈ A settings.

Layered Interference Networks With Delayed CSI: DoF Scaling With Distributed Transmitters

The layered interference network is investigated with delayed channel state information (CSI) at all nodes. It is demonstrated how multihopping can be utilized to increase the achievable degrees of freedom (DoF). In particular, a multiphase transmission scheme is proposed for the K-user 2K-hop interference network to systematically exploit the layered structure of the network and delayed CSI to achieve DoF values that scale with K. This result provides the first example of a network with distributed transmitters and delayed CSI whose DoF scales with the number of users.

Degrees of Freedom of the Interference Channel with a Cognitive Helper

In this letter, we characterize the degrees of freedom (DoF) of the K≥ 3 user Gaussian interference network with a cognitive helper where each node is equipped with a single antenna. Specifically, the users send independent messages to their corresponding receiver through their own antenna and via the help of the cognitive helper. For this network, we show that the sum DoF value is upper bounded by (K+1)/ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> when K is odd and K <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> / <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2(K+1)</sub> when K is even, respectively. While the new DoF upper bounds are simply derived based on the fact that cooperation among users does not decrease the capacity region, we provide a new achievable scheme to obtain a total of (K+1)/ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> DoF for any K≥ 3. Thus, we establish that the exact sum DoF value of the network is given as <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">(K+1)</sup> /2, whenever K is odd. The new achievable scheme is based on interference neutralization and asymptotic interference alignment.

Impaired Endogenously Evoked Automated Reaching in Parkinson's Disease

Intended reaches triggered by exogenous targets often coexist with spontaneous, automated movements that are endogenously activated. It has been posited that Parkinson's disease (PD) primarily impairs automated movements, but it is unknown to what extent this may affect multijoint/limb control, particularly when patients are off their dopaminergic medications. Here we tested nine human patients with PD while off dopaminergic medication versus nine age-matched normal controls (NCs). Participants performed intentional reaches forward to a target in a dark room and then transitioned back to their initial posture. Upon target flash, three forms of guidance were used: (1) memory with eyes closed, (2) continuous target vision only, and (3) vision of their moving finger only. The trajectories of their arm joints were measured and their joint velocities decomposed into the (intended) task-relevant and the (spontaneous) task-incidental degrees of freedom (DOF). We also measured the balance between these two subsets of DOF as these movements unfolded. In PD patients we found that the incidental DOF values were abnormally variable during the retracting movements and prevailed over the task-relevant DOF values. By contrast, their forward intentional motions were abnormally dominated by the task-relevant components. Moreover, the patients abruptly transitioned between voluntary and automated modes of joint control, and, unlike NCs, the type of visual guidance differentially affected their postural trajectories. These findings lend support to an emerging view that there is a loss of automated control in PD patients that contributes to impairments in voluntary control, and that basal ganglia-cortical circuits are critical for the maintenance and balance of multijoint control.

Polarization Degrees of Freedom of Hexapolarized MIMO System in the Ground Reflected Channel

The polarization degrees of freedom (DOF) of the hexapolarized multiple input multiple output (MIMO) system over the ground reflected channel is studied in this paper by the deterministic field solution. Using the simple two-ray model, we could get some basic understandings for the influence of a single reflecting surface on the polarization DOF of the multipolarized MIMO system. Computation results show that the number of parallel independent channels in a multipolarized MIMO system depends mainly on the communication range and the height of antennas. In free space transmission, with equal height of transmitter and receiver antennas, large polarization DOF value only occurs in the near field case and it drops sharply to 2 with the increase of transmission range. Whereas for the ground reflect channel, there will be a polarization DOF larger than 4 occurring at longer communication distance with an unequal transmitter and receiver antenna height.