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This article presents an 802.11ba-based wake-up radio (WUR) receiver that is fully integrated within an 802.11a/b/g/n/ac Wi-Fi transceiver. Low-cost integration is achieved with the WUR only occupying 0.13 mm2 while not adding any additional overhead to the Wi-Fi platform. The WUR consumes 667 $\mu \text{W}$ from 1.1-V Wi-Fi system supply. When measured from internal 0.6- and 0.9-V supplies, the receiver consumes 495 $\mu \text{W}$ . The receiver has a measured sensitivity of −92.6 dBm and can tolerate −40.5-dBm Wi-Fi adjacent channel blocker with 3-dB receiver de-sensitization. The WUR and Wi-Fi system co-operation is also demonstrated. The WUR receiver can operate when the Wi-Fi system is in sleep mode and can turn on Wi-Fi radio upon receiving 802.11ba-based wake-up packet.

Light Emitting Diodes (LED) are highly energy efficient and offer long-life times for display applications. Long life and minimal energy consumption are often the most attractive advantages for electronic devices. Because LEDs are based on compound semiconductors, which explore the direct transition between the conduction and valance band edges, thermal energy loss can be minimized during operation. However, even though these types of LEDs are based on direct transition type semiconductors, thermal energy is still emitted during operation owing to forward conduction and reverse leakage currents. This research proposes capturing this energy loss through thermoelectric module-based energy recycling methods to improve the energy efficiency of LED applications, achieving savings of up to 18%. Additional analysis was performed on high power LED sources resulting in the manufacture of a high-power LED light grid system.

An augmented-reality (AR) device which presents virtual volumetric images to switchable integrated spaces is proposed and demonstrated. A bi-focal geometric phase (GP) lens can project the integrated volumetric images to switchable integrated spaces by switching the polarization of them. For that purpose, a combination of GP lens and an active polarization switching device has been adopted. A demonstration of an AR display with switchable integrations is also provided to verify the proposed concept.

An augmented reality (AR) lightfield display can provide three-dimensional (3D) images at the locations of real objects. However, a conventional AR lightfield display has a few disadvantages in that its 3D resolution is poor and it is bulky in form owing to the use of an optical combiner or relay optics. In this paper, we propose a novel method to realize an AR lightfield display using a transparent display and an active pinhole array (APA) to enhance both the 3D resolution and visibility of real objects. An experimental demonstration verifies that the proposed method is appropriate for smart window applications.

The transmittance of the three dimensional (3D) transparent display is an important factor and can be enhanced by adding a see-through area to the displayed 3D image in order to transmit an ambient light with maximum transparency. However, there is a side effect that the perceived 3D resolution can be degraded due to the see-through area. In this paper, we propose an advanced method to resolve the above trade-off relation between the transparency and the 3D resolution by using an active parallax barrier (PB) with a see-through area. The experimental results are also presented to prove the proposed principle.

An 802.11ba-based wake-up radio (WUR) receiver is presented. The WUR receiver prototype is integrated within an 802.11a/b/g/n/ac Wi-Fi transceiver, occupying 0.05mm2 for RF/analog frontend and 0.08mm2 for digital baseband. The WUR receiver consumes 495µW standalone and consumes 667µW from Wi-Fi system supply. The receiver has a measured sensitivity of -92.6dBm and can tolerate -40.5dBm Wi-Fi adjacent channel blocker with 3dB receiver de-sensitization. The WUR receiver can operate when the Wi-Fi system is in sleep mode and can turn on Wi-Fi radio upon receiving 802.11ba-based wake-up packet over the air.

Displays based on organic light-emitting diodes (OLEDs) are now widely used in mobile devices, in which they are major power consumers. The power drawn by an OLED display increases nonlinearly with sub-pixel intensities—thus reducing brightness saves appreciable power, but can displease users. This paper examines this tradeoff, and proposes a color blending scheme in which each frame is darkened in a way that reduces power consumption significantly while limiting the visual impact. The target lightness of frames is determined, in the LAB color space, from average intensities of the original frames; and these average values are in turn obtained by adaptive sampling, so as to reduce the computational overhead. An Android smartphone uses 12%–36% less power when running this scheme, compared to standard video playback, while a user evaluation suggested that reducing brightness to a certain extent can be largely unnoticed, or readily tolerated.

In this paper, we propose a method to provide 3D image with enhanced depth range by integrating them in two central depth planes using a geometric phase lens.

INTRODUCTION Mibyeongbogam (MBBG) is a mobile application developed for subhealth status self-management in the Republic of Korea. It aims to assess a user's subhealth status, and then to recommend relevant traditional Korean medicine (TKM)-based health-promoting strategies. The purpose of this study is to evaluate the feasibility and effectiveness of MBBG's employment for the subhealth management of general healthy adults. METHODS This is a prospective, open-label, parallel group, randomized controlled trial that will seek to enroll 150 healthy adults, aged 30 to 49 years old, from 2 hospitals in the Republic of Korea. The eligible participants will then be randomly allocated to either the MBBG or control group, at a 1:1 allocation ratio. The MBBG group will use the application for 12 weeks, while the control group will undergo no intervention. The awareness of subhealth status will be primarily assessed. Health promoting behaviors, quality of life, TKM-based health questionnaires, and physical examination results will be assessed as secondary outcomes. DISCUSSION The primary endpoint will be tested with a 2-sample t test, or a Wilcoxon rank sum test. Any other continuous variables will be tested via an analysis of covariance, while categorical variables will be tested by a Chi-squared or Fisher exact test. Repeated measure analysis of variance will be performed to explore any in-group differences. The results will be addressed with a 95% confidence interval. We expect that MBBG will be the 1st TKM-based mobile application to be feasible for primary care in subhealth management. TRIAL REGISTRATION CRIS (Clinical Research Information Service), KCT0003488, February 11, 2019.

In this paper, we realize a 22-inch see-through augmented reality display using an LCD panel and a dot polarizer array which realizes an adaptive augmented reality image based on the principles of an integral imaging technique.

In recent years, the unlicensed 60 GHz band has motivated the computer, wireless communications, and consumer electronics industries to develop wireless personal area network and wireless local area network standards that support wireless applications with multigigabit data rates. One of the technical challenges is managing interference between networks in a dense environment. In this article we first show the problem of interference in a dense environment and evaluate and compare PHY and MAC layer interference mitigation techniques in terms of performance and the level of co-ordination required among interfering networks.

In this paper, the effect of the un-sampled area in the spatial interlacing 3D display is analyzed using the 2AFC method and a mirror stereoscope to optimize the perceived image quality.

The degradation of image resolution in a autostereoscopic 3D display using a directional-backlight system is a major defect to be improved. In this paper, we propose a method to enhance the perceived image quality by adopting double slit barrier array fabricated using a 3D printer.

In spite of the developments of various autostereoscopic three-dimensional (3D) technologies, the inferior resolution of the realized 3D image is a severe problem that should be resolved. For that purpose, a time-sequential 3D display is developed to provide 3D images with higher resolution and attracts much attention. Among them, a method using a directional backlight unit (DBLU) is an effective way to be adopted in liquid crystal display (LCD) with higher frame rate such as 120Hz. However, in the conventional time-sequential system, the insufficient frame rate results a flicker problem which means a recognizable fluctuation of image brightness. A dot dithering method can be a good solution for reducing that problem but it was impossible to observe the 3D image in side lobes because the image data and the directivity of light rays from the DBLU do not match in side lobes. In this paper, we propose a new vertical line dithering method to expand the area for 3D image observation by utilizing the side lobes. Since the side lobes locate in the left and right position of the center lobe, it is needed to arrange the image data in LCD panel and directivity of the light rays from the DBLU to have continuity in horizontal direction. Although the observed 3D images in side lobes are flipped ones, the utilization of the side lobes can increase the number of observers in horizontal direction.

IEEE 802.11ah enables new use cases such as smart grid and smart metering for 802.11 with an increased transmission range that reaches up to 1 km at 150 kbps. However, such a large outdoor network creates more hidden nodes due to a much higher path loss between stations than between a station to an access point (AP). 802.11ah has adopted a slotted medium access scheme and an AP assisted medium access scheme to mitigate the hidden node problem to enable energy efficient medium access for a large outdoor network. This paper presents details of the protocols being developed in the standard and evaluates the gains of the protocols.

To provide two-eyed views with one device, stereoscopic 3D (S3D) displays interlace the two views either temporally or spatially: temporal interlacing (TI) alternates the two views in time with full resolution, while spatial interlacing (SI) presents the two views simultaneously but with half resolution for each eye. We investigate the effect of interlacing methods on image quality through a psychophysical experiment. We compared four experimental conditions: three S3D interlacing methods (TI, SI with raw sampling, and SI with vertical interpolation), and one nonconventional interlacing method (vertical interpolation). The stimuli were 10 natural stereo images presented at nine levels of pixel sizes (0.64, 0.78, 0.89, 1.00, 1.28, 1.55, 1.78, 2.00, and 2.56 arcmin). To test the effect of interlacing methods per se, we provided all the experimental conditions to the subjects using a single experimental setup: a mirror stereoscope. The results show that TI does not degrade the image quality for any pixel size. SI degrades the image quality when the pixel size is relatively large, but the effect of the two SI methods does not differ significantly. Comparison of SI methods against the vertical interpolation method implies that the primary cause of the degradation in image quality for SI methods is the visibility of the interlacing pattern rather than the loss of high-frequency information.

The perceived resoltuions of the parallax barrier and the lenticular array are compared using a mirror stereoscope. Although the physical number of pixels consisting the 3D images are same for the two methods, the observer perceived them differently.

Device-to-device (D2D) discovery is an important step toward numerous applications of device-to-device communications. However, the design of D2D discovery protocols also faces the challenges of distributed nature, energy efficiency, scalability, and fast discovery. In this paper, we propose a D2D discovery protocol called synced distributed protocol that can efficiently resolve these challenges. The key idea behind our protocol is to group devices in a neighborhood such that devices in a group will take turns to announce the existence of other devices in a group. Hence, a device can reduce the period of announcing its existence and have the advantages of energy efficiency and scalability. Further, the transmissions from other devices in the group still guarantee fast discovery. We validate our protocol design by analysis and simulations. Specifically, we prove that our proposed protocol will function correctly in a static environment with minor assumptions and simulate our protocol in the OPNET 802.11n model. Simulation results confirm that our algorithm is scalable and can achieve low duty cycle and fast discovery. For mobile environment, we propose enhanced techniques and use simulation to show that the enhanced techniques has the benefits of increasing the group size.

In this paper, we study for comparison of perceived resolution between the active retarder and patterned retarder 3D displays using a haploscope to eliminate an additional distortion or noise from the additional optics.

The loss of resolution is one of the most important issues of autostereoscopic displays which should be resolved. In this paper, a method to realize an autostereoscopic liquid crystal display with full-resolution and reduced flicker using a multi-directional backlight unit is proposed.

Human respiratory syncytial virus (hRSV) typically affects newborns and young children. Even though it can cause severe and, in some cases, lifelong respiratory infections, there are currently no Food and Drug Administration (FDA)-approved therapeutics that control this virus. The hRSV F protein facilitates viral fusion, a critical extracellular event that can be targeted for therapeutic intervention by disrupting the assembly of a postfusion 6-helix bundle (6HB) within the hRSV F protein. Here we report the development of a fluorescence polarization (FP) assay using an engineered hRSV F protein 5-helix bundle (5HB). We generated the 5HB and validated its ability to form a 6HB in an FP assay. To test the potential of 5HB as a screening tool, we then investigated a series of truncated peptides derived from the "missing" sixth helix. Using this FP-based 5HB system, we have successfully demonstrated that short peptides can prevent 6HB formation and serve as potential hRSV fusion inhibitors. We anticipate that this new 5HB system will provide an effective tool to identify and study potential antivirals to control hRSV infection.

There has been intense commercial interest recently to enable wireless personal area network (WPAN) and wireless local area network (WLAN) applications over 60 GHz. In this paper, we consider the quality of service (QoS) support for usage scenarios that deliver high definition compressed video along with other data applications over 60 GHz in a relatively dense environment. Requirements and potential solutions are identified to support variable bit rate (VBR) traffic and coexistence of overlapping networks. Our investigation shows that a combination of medium access control (MAC) schemes such as time division multiple access (TDMA) with either carrier sense multiple access (CSMA) or polling may provide QoS guarantee while utilizing the channel efficiently. For support of overlapping networks, it is critical to address both intra- and inter-system interference from homogeneous and heterogeneous networks, respectively. While intra-system interference mitigation and management mechanisms should be incorporated into the MAC and physical (PHY) layers design of the system; inter-system interference may be managed through techniques such as common channelization, energy or preamble detection and avoidance.

In this paper, a method to construct a directional-backlight unit system to separate the left-eye image and the right-eye image by adopting a double-slit barrier array is proposed to enhance the perceived quality of the realized 3D image. Additionally, the two-dimensional/three-dimensional convertible function is also realized by adopting an active diffuser to the spatial interlacing directional-backlight system.