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The current method of Vcom adjustment in VR products is to start with the smallest Vcom and increase the voltage with a larger adjustment step while testing the change in flicker value, the flicker value will slowly decrease and when the flicker value starts to get bigger, reduce the adjustment step and adjust the Vcom in the opposite direction until the second flicker gets bigger and meets the specification, then the optimum Vcom will be found (quotes) [1].There are obvious drawbacks to this current approach: 1. Dueto the different optimal Vcom of different modules, the time to find the optimal Vcom is long and not fixed;2. Vcom will drift with time (Vcom Drift), the problem of irregular time will lead to increased risk of Flicker NG. In order to solve the shortcomings of the current Vcom adjustment methods, we introduced the mathematical theory and deduced the Vcom calculation process to establish the deterministic‐Vcom (D‐Vcom) algorithm. After experiments, the DVcom algorithm can effectively reduce the Vcom adjustment time and has the advantage of fixed adjustment time. This is very helpful for the actual production efficiency and optical stability of the products. [ABSTRACT FROM AUTHOR]

As the market for near‐eye display devices and other similar devices expands, these devices and their display performance are receiving more and more attention and challenges. Therefore, this paper reports a display module consisting of a high PPI fast LCD based on LTPS backplane paired with an ultra‐multi‐partition Mini‐LED backlight. The display adopts a new pixel structure and is able to achieve a transmission rate of 1.8% and a high contrast ratio of 500:1 on 1411 PPI. Besides, the multi‐partition Mini‐LED backlight unit is able to achieve 1728 partitions of local dimming and high dynamic contrast ratio of the display module, meanwhile the brightness of the backlight is increased by 4.9% with the same power consumption, making the overall display module brighter. [ABSTRACT FROM AUTHOR]

With the expansion of the markets about near‐eye display devices and other similar consumer devices, the highly optical efficiency and display performance of these devices have also received more and more attention and challenge. So in this paper, a novel backlight unit for liquid crystal display (LCD) is reported. The angle of the radiation can change with the position of the active area (AA) in two directions. The change range of the chief radiation angle can vary more than ±20°. In the meanwhile, with the same power consumption, the brightness of the backlight can achieve or exceed the existing brightness level of the backlight. [ABSTRACT FROM AUTHOR]

Summary: As a typical representative of distributed computing framework, Spark has been continuously developed and popularized. It reduces the data transmission time through efficient memory‐based operations and solves the shortcomings of the traditional MapReduce computation model in iterative computation. In Spark, data skew is very prominent due to the uneven distribution of input data and the unbalanced allocation of default partitioning algorithm. When data skew occurs, the execution efficiency of the program will be reduced, especially in the reduce stage of Spark. Therefore, this paper proposes ReducePartition to solve data skew problem at reduce stage of Spark platform. First, the compute node samples the local data according to the sampling algorithm to predict the overall characteristics of data distribution. Then, to take full use of cluster resources, ReducePartition divides data into multiple partitions evenly. Next, taking into account the differences in computational capabilities among Executors, each task is assigned to Executor with the highest performance factor according to the greedy strategy. Finally, the results of the related algorithms and ReducePartition are compared by using WordCount benchmark and Sort benchmarks on heterogeneous Spark standalone cluster. The performance of the ReducePartition under different degree of data skew and different data size is analyzed. Experimental results show that the proposed algorithm can effectively reduce the impact of data skew on the total makespan of Spark big data applications, and the average total makespan is reduced by 30% to 50% while resource utilization is increased by 20%‐30% on average. [ABSTRACT FROM AUTHOR]

With the expansion of the markets about near‐eye display devices and other similar consumer devices, the security of display devices has also received more and more attention. So in this paper, a novel low blue light backlight unit for eye‐protective liquid crystal display is reported. The low blue light characteristic is achieved by a LED with long wavelength (>457nm) chip and K2SiF6:Mn4+phosphors or Red/Green phosphors. The screen with this backlight unit can realize 86% NTSC color gamut with a slight decrease in brightness, 8% or so. In addition, the ratio of toxic blue light region (wavelength ranges from 415nm to 450nm) to the whole blue light region (wavelength ranges from 400nm to 500nm) is less than 40%. Especially, the ratio can be less than 15% if using the chip with longer wavelength (>460nm) and Red/Green phosphors. The screen also reaches the TÜV Rheinland low blue light display certification standard. [ABSTRACT FROM AUTHOR]

The emergence of cloud computing based on virtualization technologies brings huge opportunities to host virtual resource at low cost without the need of owning any infrastructure. Virtualization technologies enable users to acquire, configure, and be charged on pay-per-use basis. However, cloud data centers mostly comprise heterogeneous commodity servers hosting multiple virtual machines (VMs) with potential various specifications and fluctuating resource usages, which may cause imbalanced resource utilization within servers that may lead to performance degradation and service level agreements violations. So as to achieve efficient scheduling, these challenges should be addressed and solved by using load balancing strategies, which have been proved to be nondeterministic polynomial time (NP)-hard problem. From multiple perspectives, this work identifies the challenges and analyzes existing algorithms for allocating VMs to hosts in infrastructure clouds, especially focuses on load balancing. A detailed classification targeting load balancing algorithms for VM placement in cloud data centers is investigated, and the surveyed algorithms are classified according to the classification. The goal of this paper is to provide a comprehensive and comparative understanding of existing literature and aid researchers by providing an insight for potential future enhancements. [ABSTRACT FROM AUTHOR]

Our paper considers the following fundamental scheduling problem. There are n deterministic jobs to be scheduled offline on multiple identical machines, which have bounded capacities. Each job is associated with a start-time, an end-time, a process time, and demand for machine capacity. The goal is to schedule all of the jobs non-preemptively in their start-time-end-time windows, subject to machine capacity constraints such that the total busy time of the machines is minimized. We refer to this problem as minimizing the total busy time for the scheduling of multiple identical machines (MinTBT). This problem has important applications in power-aware scheduling for Cloud computing, optical network design, customer service systems, and other related areas. Scheduling to minimize busy times is already NP-hard in the special case where all jobs have the same process time and can be scheduled in a fixed time interval. One best-known result for this problem is a 5-approximation algorithm for special instances using first-fit-decreasing algorithm. In this paper, we propose and prove a 3-approximation algorithm, modified first-fit-decreasing-earliest for the general case and obtain more results for special cases. We then show how our results are applied in cloud computing to improve the energy efficiency. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY The statistical multiplexer problem was analyzed extensively in the discrete-time case within the context of ATM access networks or Internet. Despite the vast literature on ATM multiplexer, this problem has not been satisfactorily analyzed in the continuous-time case. In this paper, a statistical multiplexer consisting of a single server queue is modeled and analyzed. N identical interrupted Poisson process arrivals flow into the multiplexer are considered, the service time is assumed to be exponentially distributed, and the queue size is infinite. We developed an efficient way to approximate the superposition of n interrupted Poisson process (or n MMPP 2) arrival process by an MMPP 2 through moments and index of dispersion count (IDC) matching. We then find the closed-form Laplace transform of the departure process of an MMPP 2/M/1 queue. Our results prove that the departure process of an MMPP 2/M/1 queue is not an MMPP 2, which closes the long open problem that whether the departure process of an MMPP/M/1 can be a MMPP. Using Laplace transform matching, we approximated the departure process of an MMPP 2/M/1 by an MMPP 2. These results permit us to analyze a number of statistical multiplexer linked in series as they arise in an access network. Numerical experiments show that approximate analytical results match the simulation results very well. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Brightness adjustment is an essential part during the production of OLED (Organic Light‐emitting Diode) module. To acquire the highest brightness, it usually takes one or more tests without the guidance of valid methods or theories. Based on the OLED light‐emitting principles, this paper sets out to investigate into the brightness adjustment process and calculate the maximum brightness of module in theory [Equation (4−6)] on the premise of the fixated white point. With the comparison of OLED module experimental results (Table 2), it shows that calculated values are well compatible with module maximum brightness test values, which is instructive and meaningful in the adjustment of OLED module. [ABSTRACT FROM AUTHOR]

We have developed a unique method to improve brightness homogeneity of VR display. Through this method, not only we can decrease the difference in brightness of two displays modules significantly, but also can improve the max brightness and decrease the back‐light‐unit (BLU) loss which is very expansive device. [ABSTRACT FROM AUTHOR]