Glass Devices Research Articles

사례연구를 통한 DSC에 의한 BIPV 가능성 분석 연구

건물에너지 자립과 온실가스 배출 저감에 BIPV 역할이 증대되는 가운데 기존 결정계의 한계를 극복할 수 있는 DSC의 적용이 주목받고 있다. 특히 DSC의 다양한 색상과 투명성 그리고 방향에 무관한 작동성은 모듈의 다기능 복합재로서 BIPV폭을 크게 확장시킨다. 이에 사례조사 분석을 통해 DSC BIPV의 가능성을 살펴보고 그 활용성을 조망한다. 국 내외 각 3건씩의 사례 조사 분석을 통해 나타난 대부분의 DSC BIPV는 주로 창호와 차양 장치로 구현되고 있고 이는 DSC의 특성과 무관치 않다. 즉, 다양한 색상과 투명성의 모듈은 건물 외피디자인과 에너지 획득에 커다란 전환점을 마련하고 있는 것으로 파악된다. 한편으로는 적용모듈의 색상으로 인한 눈의 자극성이 존재하여 BIPV 창호적용에는 건물 및 실의 용도에 따른 색감 고려가 필수적이고 건물외피 적용을 위한 유연한 모듈개발의 경우 DSC BIPV는 상당히 기대되는 확산성을 가질 것이다. The various colors and transparency of DSC and operability unrelated with directions greatly expand the use of BIPV, as a multi-functional composite of module. Therefore the possibility of DSC BIPV is examined by the case study and the analysis and then its applicability is examined. Most of the DSC BIPVs, which are found through a total of six case studies and analyzes in Korea and abroad, are mainly implemented with window glass and shading devices. This is related to the DSC transparency property. Improvements are due to the irritation of the eye due to the color of the red module. Therefore, it is important to take into account the color of the BIPV window depending on the use of the building and the room. Meanwhile, some colors of application model may stimulate eyes and such colors should be considered by use of buildings and rooms in the application of BIPV window. DSC BIPV has prospective diffusibility with the development of flexible module for the application of building surface.

Control of oxygen tension recapitulates zone-specific functions in human liver microphysiology systems.

This article describes our next generation human Liver Acinus MicroPhysiology System (LAMPS). The key demonstration of this study was that Zone 1 and Zone 3 microenvironments can be established by controlling the oxygen tension in individual devices over the range of ca. 3 to 13%. The oxygen tension was computationally modeled using input on the microfluidic device dimensions, numbers of cells, oxygen consumption rates of hepatocytes, the diffusion coefficients of oxygen in different materials and the flow rate of media in the MicroPhysiology System (MPS). In addition, the oxygen tension was measured using a ratiometric imaging method with the oxygen sensitive dye, Tris(2,2'-bipyridyl) dichlororuthenium(II) hexahydrate (RTDP) and the oxygen insensitive dye, Alexa 488. The Zone 1 biased functions of oxidative phosphorylation, albumin and urea secretion and Zone 3 biased functions of glycolysis, α1AT secretion, Cyp2E1 expression and acetaminophen toxicity were demonstrated in the respective Zone 1 and Zone 3 MicroPhysiology System. Further improvements in the Liver Acinus MicroPhysiology System included improved performance of selected nonparenchymal cells, the inclusion of a porcine liver extracellular matrix to model the Space of Disse, as well as an improved media to support both hepatocytes and non-parenchymal cells. In its current form, the Liver Acinus MicroPhysiology System is most amenable to low to medium throughput, acute through chronic studies, including liver disease models, prioritizing compounds for preclinical studies, optimizing chemistry in structure activity relationship (SAR) projects, as well as in rising dose studies for initial dose ranging. Impact statement Oxygen zonation is a critical aspect of liver functions. A human microphysiology system is needed to investigate the impact of zonation on a wide range of liver functions that can be experimentally manipulated. Because oxygen zonation has such diverse physiological effects in the liver, we developed and present a method for computationally modeling and measuring oxygen that can easily be implemented in all MPS models. We have applied this method in a liver MPS in which we are then able to control oxygenation in separate devices and demonstrate that zonation-dependent hepatocyte functions in the MPS recapitulate what is known about invivo liver physiology. We believe that this advance allows a deep experimental investigation on the role of zonation in liver metabolism and disease. In addition, modeling and measuring oxygen tension will be required as investigators migrate from PDMS to plastic and glass devices.

A Cardiac Early Warning System with Multi Channel SCG and ECG Monitoring for Mobile Health.

Use of information and communication technology such as smart phone, smart watch, smart glass and portable health monitoring devices for healthcare services has made Mobile Health (mHealth) an emerging research area. Coronary Heart Disease (CHD) is considered as a leading cause of death world wide and an increasing number of people die prematurely due to CHD. Under such circumstances, there is a growing demand for a reliable cardiac monitoring system to catch the intermittent abnormalities and detect critical cardiac behaviors which lead to sudden death. Use of mobile devices to collect Electrocardiography (ECG), Seismocardiography (SCG) data and efficient analysis of those data can monitor a patient’s cardiac activities for early warning. This paper presents a novel cardiac data acquisition method and combined analysis of Electrocardiography (ECG) and multi channel Seismocardiography (SCG) data. An early warning system is implemented to monitor the cardiac activities of a person and accuracy assessment of the early warning system is conducted for the ECG data only. The assessment shows 88% accuracy and effectiveness of our proposed analysis, which implies the viability and applicability of the proposed early warning system.

Electrical bistabilities and memory mechanisms of nonvolatile organic bistable devices based on exfoliated muscovite-type mica nanoparticle/poly(methylmethacrylate) nanocomposites

Organic bistable devices (OBDs) with exfoliated mica nanoparticles (NPs) embedded into an insulating poly(methylmethacrylate) (PMMA) layer were fabricated by using a spin-coating method. Current–voltage (I–V) curves for the Al/PMMA/exfoliated mica NP/PMMA/indium-tin-oxide/glass devices at 300K showed a clockwise current hysteresis behavior due to the existence of the exfoliated muscovite-type mica NPs, which is an essential feature for bistable devices. Write-read-erase-read data showed that the OBDs had rewritable nonvolatile memories and an endurance number of ON/OFF switching for the OBDs of 102 cycles. An ON/OFF ratio of 1×103 was maintained for retention times larger than 1×104s. The memory mechanisms of the fabricated OBDs were described by using the trapping and the tunneling processes within a PMMA active layer containing exfoliated muscovite-type mica NPs on the basis of the energy band diagram and the I–V curves.

Mid-infrared astrophotonics: study of ultrafast laser induced index change in compatible materials

The mid-infrared wavelength regime 3.5 – 4.1μm, known as the astronomical L’ band is of special interest for exoplanet hunting. Mid-IR compatible photonic technologies are an enabling platform for a range of critical observational science using compact instruments on the next generation of Extremely Large Telescopes. Pupil remapping interferometry is a technique in which subapertures of the telescope pupil (2D) are reformatted into a 1D linear array. This can be done efficiently using 3D photonics. One of the most important techniques to fabricate 3D photonic devices in glass is ultrafast laser inscription. However, common silicate glasses are opaque above 2–2.2 μm and therefore not useful for the fabrication of waveguides at mid-infrared wavelengths. Here we present a study of mid-infrared transparent materials that are compatible with the ultrafast laser inscription technique. This study will inform the development of mid-infrared photonic devices for future exoplanetary discovery.

Microfluidic fluorescence-activated cell sorting (μFACS) chip with integrated piezoelectric actuators for low-cost mammalian cell enrichment

A low-cost, microfluidic fluorescence-activated cell sorting (μFACS) microchip integrated with two piezoelectric lead–zirconate–titanate actuators was demonstrated for automated, high-performance mammalian cell analysis and enrichment. In this PDMS–glass device, cells were hydrodynamically focused into a single file line in the lateral direction by two sheath flows, and then interrogated with a forward scattering and confocal fluorescent detection system. The selected cells were displaced transversely into a collection channel by two piezoelectric actuators that worked in a pull–push relay manner with a minimal switching time of ~0.8 ms. High detection throughput (~2500 cells/s), high sorting rate (~1250 cells/s), and high sorting efficiency (~98%) were successfully achieved on the μFACS system. Six cell mixture samples containing 22.87% of GFP-expressing HeLa cells were consecutively analyzed and sorted on the chip, revealing a stable sorting efficiency of 97.7 ± 0.93%. In addition, cell mixtures containing 37.65 and 3.36% GFP HeLa cells were effectively enriched up to 83.82 and 78.51%, respectively, on the microchip, and an enrichment factor of 105 for the low-purity (3.36%) sample was successfully obtained. This fully enclosed, disposable microfluidic chip provides an automated platform for low-cost fluorescence-based cell detection and enrichment, and is attractive to applications where cross-contamination between runs and aerosol hazard are the primary concerns.

High‐Throughput Step Emulsification for the Production of Functional Materials Using a Glass Microfluidic Device

High‐volume production of monodisperse droplets is of importance for industrial applications due to increased emulsion stability, precise control over droplet volumes, and the formation of periodic arranged structures. So far, parallelized microfluidic devices are limited by either their complicated channel geometry or by their chemically or thermally unstable embedding material. This study shows a scalable microfluidic step emulsification chip that enables production of monodisperse emulsions at a throughput of up to 25 mL h−1 in a glass device with 364 linearly parallelized droplet makers. The chemical and thermal stability of such a glass device allows for the preparation of a broad variety of functional particles and microdroplets by using any desired solvent together with nanoparticles, polymers, and hydrogels. Moreover, the microfluidic device can be stringently cleaned for nearly unlimited use and permits the alternating production of oil‐in‐water and water‐in‐oil emulsions. The combined high throughput, chemical and thermal stability offered by our device enables production of monodisperse functional materials for large‐scale applications. image

Rapid wave velocity measurement by Brillouin scattering using artificially induced phonon

Brillouin light scattering enables measurements of hypersonic longitudinal and shear velocities in the small area (diameter about 50 μm). One problem of the conventional Brillouin technique is the weak Brillouin scattering peak from thermal phonons and this results in the longer measurement time. To overcome this problem, we have proposed measurements of strong coherent phonons by fabricating a high frequency transducer on the sample surface. However, the fabrication of the transducer is not suitable for simple and nondestructive measurements. In this study, a small glass device with a ZnO piezoelectric thin film was used as a hypersonic transducer around 1 GHz. By attaching this transducer to the sample with coupling liquid, artificial coherent phonons were successfully induced in a sample. In the case of a quarts sample, strong Brillouin scattering peaks were observed using a tandem Fabry-Perot interferometer. The measured frequency shift of the peaks was equal to the excitation frequency of the ZnO pie...

Fractional resurfacing in the Asian patient: Current state of the art.

Fractionated photothermolysis (FP) has revolutionized modern laser technology. By creating selective columns of microthermal damage, fractionated devices allows for greater treatment depths to be achieved without the prolonged downtime and risk of complications seen in traditional fully ablative laser resurfacing. Fractional resurfacing is a proven method to treat a variety of cutaneous conditions. In the Caucasian patient, a wide range of devices and treatment settings can be utilized safely and effectively. However, ethnic skin requires special consideration due to its unique pigmentary characteristics and clinical presentations. In this review article, we detail the current indications and strategies to optimize results and mitigate complications when utilizing fractional resurfacing for the Asian patient. A review of the MEDLINE English literature was conducted on fractionated laser devices studied in the Asian population. Articles included describe non-ablative devices including fractionated erbium glass, thulium fiber, diode, and radiofrequency devices; and ablative devices including fractionated carbon dioxide (CO2 ) laser, erbium yttrium aluminum garnet and yttrium scandium gallium garnet (YSGG) laser. These data were integrated with the expert opinion of the authors. Taking into account the unique characteristics and cosmetic concerns of the Asian population, fractional resurfacing can be considered a safe and effective option for the treatment of atrophic and hypertrophic scarring, and photorejuvenation in ethnic skin types. Select cases of melasma may be treated with fractionated non-ablative devices, but utilized with caution. The predominant complication associated with fractional resurfacing for these conditions is post-inflammatory hyperpigmentation (PIH) and rebound worsening of melasma. A greater number of treatments at lower density settings and wider treatment intervals typically produce the lowest risks of PIH without compromising treatment efficacy. Lasers Surg. Med. 49:45-59, 2017. © 2016 Wiley Periodicals, Inc.

3D Printed Micro Free-Flow Electrophoresis Device.

The cost, time, and restrictions on creative flexibility associated with current fabrication methods present significant challenges in the development and application of microfluidic devices. Additive manufacturing, also referred to as three-dimensional (3D) printing, provides many advantages over existing methods. With 3D printing, devices can be made in a cost-effective manner with the ability to rapidly prototype new designs. We have fabricated a micro free-flow electrophoresis (μFFE) device using a low-cost, consumer-grade 3D printer. Test prints were performed to determine the minimum feature sizes that could be reproducibly produced using 3D printing fabrication. Microfluidic ridges could be fabricated with dimensions as small as 20 μm high × 640 μm wide. Minimum valley dimensions were 30 μm wide × 130 μm wide. An acetone vapor bath was used to smooth acrylonitrile-butadiene-styrene (ABS) surfaces and facilitate bonding of fully enclosed channels. The surfaces of the 3D-printed features were profiled and compared to a similar device fabricated in a glass substrate. Stable stream profiles were obtained in a 3D-printed μFFE device. Separations of fluorescent dyes in the 3D-printed device and its glass counterpart were comparable. A μFFE separation of myoglobin and cytochrome c was also demonstrated on a 3D-printed device. Limits of detection for rhodamine 110 were determined to be 2 and 0.3 nM for the 3D-printed and glass devices, respectively.

Low-loss photonic device in Ge-Sb-S chalcogenide glass.

Low-loss waveguides constitute an important building block for integrated photonic systems. In this work, we investigated low-loss photonic device fabrication in Ge23Sb7S70 chalcogenide glass using electron beam lithography followed by plasma dry etching. High-index-contrast waveguides with a low propagation loss of 0.5dB/cm and microdisk resonators with an intrinsic quality factor (Q-factor) of 1.2×106 were demonstrated. Both figures represent, to the best of our knowledge, the best low-loss results reported thus far in submicrometer single-mode chalcogenide glass devices.

Accuracy of remote chest X-ray interpretation using Google Glass technology

ObjectivesWe sought to explore the accuracy of remote chest X-ray reading using hands-free, wearable technology (Google Glass, Google, Mountain View, California). MethodsWe compared interpretation of twelve chest X-rays with 23 major cardiopulmonary findings by faculty and fellows from cardiology, radiology, and pulmonary-critical care via: (1) viewing the chest X-ray image on the Google Glass screen; (2) viewing a photograph of the chest X-ray taken using Google Glass and interpreted on a mobile device; (3) viewing the original chest X-ray on a desktop computer screen. One point was given for identification of each correct finding and a subjective rating of user experience was recorded. ResultsFifteen physicians (5 faculty and 10 fellows) participated. The average chest X-ray reading score (maximum 23 points) as viewed through the Google Glass, Google Glass photograph on a mobile device, and the original X-ray viewed on a desktop computer was 14.1±2.2, 18.5±1.5 and 21.3±1.7, respectively (p<0.0001 between Google Glass and mobile device, p<0.0001 between Google Glass and desktop computer and p=0.0004 between mobile device and desktop computer). Of 15 physicians, 11 (73.3%) felt confident in detecting findings using the photograph taken by Google Glass as viewed on a mobile device. ConclusionRemote chest X-ray interpretation using hands-free, wearable technology (Google Glass) is less accurate than interpretation using a desktop computer or a mobile device, suggesting that further technical improvements are needed before widespread application of this novel technology.

Use of Fitness Bands by Teachers in the Classroom

Wearable technologies are increasingly gaining attention. Gadgets such as Smartwatch, Fitband, Google Glass, and similar healthcare devices can be worn by the consumer and have several benefits in various contexts. This study examined teachers perception on fitness bands and if they have any benefits to classroom teachers. 28 classroom teachers were each given a fitness band for 35 days. Prior to giving them the fitness band, a pre-survey was administered. At the end of the 35 day period a post-survey was administered. Ninety-three percent of the teachers completed both the post and pre-survey in which they responded to change in teacher motivation and teaching practices due to wearing the fitness band. There were also four open ended questions that addressed benefits and challenges of using the fitness band in educational contexts. This study has implications for those considering using fitness band in an educational setting.

Movee: Video Liveness Verification for Mobile Devices Using Built-In Motion Sensors

The ubiquitous and connected nature of camera-equipped mobile devices has greatly increased the value and importance of visual information they capture. Today, broadcasting videos from camera phones uploaded by unknown users is admissible on news networks, and banking customers expect to be able to deposit checks using mobile devices. In this paper, we introduce Movee, a system that addresses the fundamental question of whether the visual stream uploaded by a user has been captured live on a mobile device, and has not been tampered with by an adversary. Movee leverages the mobile device motion sensors and the intrinsic user movements during the shooting of the video. Movee exploits the observation that the movement of the scene recorded on the video stream should be related to the movement of the device simultaneously captured by the accelerometer. Contrary to existing algorithms, Movee has the unique strength of not depending on the audio track. We introduce novel attacks that focus on Movee's defenses, to fabricate acceleration data that mimics the motion observed in targeted videos. We use smartphones and wearable smart glasses to collect both genuine and attack data from 13 users. Our experiments show that Movee is able to efficiently detect human and automatically generated plagiarized videos: Movee's accuracy ranges between 68-93 percent on a smartphone, and between 76-91 percent on a Google Glass device.

Fast production of microfluidic devices by CO2 laser engraving of wax-coated glass slides.

Glass is one of the most convenient materials for the development of microfluidic devices. However, most fabrication protocols require long processing times and expensive facilities. As a convenient alternative, polymeric materials have been extensively used due their lower cost and versatility. Although CO2 laser ablation has been used for fast prototyping on polymeric materials, it cannot be applied to glass devices because the local heating causes thermal stress and results in extensive cracking. A few papers have shown the ablation of channels or thin holes (used as reservoirs) on glass but the process is still far away from yielding functional glass microfluidic devices. To address these shortcomings, this communication describes a simple method to engrave glass-based capillary electrophoresis devices using standard (1mm-thick) microscope glass slides. The process uses a sacrificial layer of wax as heat sink and enables the development of both channels (with semicircular shape) and pass-through reservoirs. Although microscope images showed some small cracks around the channels (that became irrelevant after sealing the engraved glass layer to PDMS) the proposed strategy is a leap forward in the application of the technology to glass. In order to demonstrate the capabilities of the approach, the separation of dopamine, catechol and uric acid was accomplished in less than 100s.

Effects of substrate temperature on the structural, optical and resistive switching properties of HfO2 films

We systematically investigated the effects of substrate temperature on the structural and optical properties and resistive switching behaviors of HfO2 films. HfO2 films were prepared by using electron beam evaporation under different substrate temperatures. The results show that with the increasing substrate temperature, the amorphous HfO2 films were transformed to the crystalline state and the spherical surface grain size also increases. All the HfO2 films exhibited high transmittance in the near ultra-violet and visible light regions, and the absorption edge revealed an obvious blue-shift with an increase of substrate temperature. The Ti/HfO2/ITO/glass device exhibited excellent bipolar resistive switching behaviors with a high resistance ratio of 104.

Refractive index and dispersion control of ultrafast laser inscribed waveguides in gallium lanthanum sulphide for near and mid-infrared applications.

The powerful ultrafast laser inscription technique is used to fabricate optical waveguides in gallium lanthanum sulphide substrates. For the first time the refractive index profile and the dispersion of such ultrafast laser inscribed waveguides are experimentally measured. In addition the Zero Dispersion Wavelength of both the waveguides and bulk substrate is experimentally determined. The Zero Dispersion Wavelength was determined to be between 3.66 and 3.71 μm for the waveguides and about 3.61 μm for the bulk. This work paves the way for realizing ultrafast laser inscribed waveguide devices in gallium lanthanum sulphide glasses for near and mid-IR applications.

A Microdosimetric Analysis of Absorbed Dose to Tumor as a Function of Number of Microspheres per Unit Volume in 90Y Radioembolization.

Differences in maximum tolerable absorbed dose to normal liver between (90)Y radioembolization and external-beam radiation therapy have been explained by citing differences in absorbed-dose heterogeneity at the microscopic level. We investigated microscopic absorbed-dose heterogeneity in radioembolization as a function of the number of microspheres per unit volume in tumor. The goal was to determine what effect the number of microspheres may have, if any, on tumor control in (90)Y radioembolization. (90)Y PET/CT data were combined with microscopic probability-density functions describing microsphere clustering to provide realistic simulation using Monte Carlo modeling on both a macroscopic and a microscopic level. A complete microdosimetric analysis using 100-μm voxels was performed on the basis of (90)Y PET/CT data from 19 tumors treated using radioembolization. Simulations were performed with average tumor microsphere-number densities from 200 to 70,000 spheres/mL. Monte Carlo simulations of each tumor and number density were repeated 20 times to establish SE. A 2-way balanced ANOVA was used to determine whether differences in microsphere-number density affected common tumor-dose metrics. Decreasing the microsphere-number density resulted in a decrease in D70, the minimum dose to 70% of the tumor. The slope of the dose-volume histogram also decreased with decreasing microsphere-number density in all tumors. Compared with a density of 50,000 spheres/mL, decreases in D70 were statistically significant below 20,000 spheres/mL. However, these differences are unlikely to have clinical significance until the density decreases to below 5,000 spheres/mL. Although D70 was decreased at a low microsphere-number density, one can compensate for decreases by an increase in the average tumor-absorbed dose, that is, by increasing the radioembolization treatment dose. Differences in microsphere-number density may have an effect on microscopic tumor absorbed-dose inhomogeneity. These results begin to explain differences in treatment planning strategies between glass and resin radioembolization devices.

평판디스플레이용 유리의 박판화공정을 위한 비불산형 식각액

기존의 불산을 대체할 수 있는 평판디스플레이용 유리의 식각용액을 개발하고자 진행하였다. 본 연구과정을 통해 제안된 불산 대체 유리 식각용액은 산성불화암모늄 18~19 wt%, 황산 24~25 wt%, 물 45~46 wt%, 황산염 4~5 wt%, 규불화염 7~8 wt%로 구성되며, 사용된 식각용액의 재사용 시 보충용액으로서 해당조성의 식각용액을 전체의 5% 되게 보충함으로서 효과적으로 지속적으로 재사용이 가능하다. 개발된 식각용액은 <TEX>$30^{\circ}C$</TEX>에서 <TEX>$5{\mu}m/min$</TEX> 이상의 식각속도를 나타내며, 반복 재사용 시에도 초기 식각액 전체 질량의 5% 추가로 보충함으로서 식각속도는 <TEX>$0.1{\mu}m/min$</TEX> 이하로 편차로 식각속도가 안정적으로 유지되었다. 이 식각공정을 통해 얻어진 평판디스플레이용의 유리의 표면 상태는 Pin hole, Dimple 등이 발견되지 않는 양호한 품질을 나타내었다. The purpose of this research was to develop a flat panel display device's glass etchant which can replace hydrofluoric acid. The glass etchant was composed of 18~19% wt% of ammonium hydrogen fluoride, 24~25 wt% of sulfuric acid, 45~46 wt% of water, 4~5 wt% of sulfate and 7~8 wt% of fluoro-silicate. By replenishing the etchant which has the amount of 5% of initial solution's mass, it was possible to reuse the etchant continuously. The developed etchant showed <TEX>$5{\mu}m/min$</TEX> of etching rate at <TEX>$30^{\circ}C$</TEX>. The reusable etchant, with replenishing 5% of initial etchant mass showed the stable etching rate, which has the deviation of less than <TEX>$0.1{\mu}m/min$</TEX> etching rate. The glass surface of flat panel display device created from our etching process was in good condition with any defects such as pin hole and dimple.

Effect of metal ion concentration in Ni–W plating solution on surface roughness of Ni–W film

Since nanopatterns are used for various purposes including solar cells, super-hydrophilicity, and biosensors, it is necessary to miniaturize the patterns on glass devices from micro- to nano-order. We have studied glass imprinting as an excellent microfabrication technology for glass devices. Uniformity of the nanopattern height is required for a mold, since a nodular structure on the Ni–W surface is recognized as a problem in Ni–W nanopattern formation. We confirmed that the Ni–W plating bath increasing metal ion concentration is effective for inhibition of the nodular structure on the Ni–W film, and succeeded in Ni–W nano pattern formation with uniform height. However, the W content rate of plated Ni–W film was reduced in exchange for enhancing the flatness of the Ni–W film. It is necessary to examine the Ni–W plating condition for obtaining planarization of the Ni–W surface and a high content rate of W in the Ni–W film.