5,322 research outputs found

    High-resolution, reconfigurable printing of liquid metals with three-dimensional structures

    Get PDF
    We report an unconventional approach for high-resolution, reconfigurable 3D printing using liquid metals for stretchable, 3D integrations. A minimum line width of 1.9 ??m can be reliably formed using direct printing, and printed patterns can be reconfigured into diverse 3D structures with maintaining pristine resolutions. This reconfiguration can be performed multiple times, and it also generates a thin oxide interface that can be effective in preventing the spontaneous penetration of gallium atoms into different metal layers while preserving electrical properties under ambient conditions. Moreover, these free-standing features can be encapsulated with stretchable, conformal passivations. We demonstrate applications in the form of a reconfigurable antenna, which is tunable by changing geometeries, and reversibly movable interconnections used as mechanical switches. The free-standing 3D structure of electrodes is also advantageous for minimizing the number and space between interconnections, which is important for achieving higher integrations, as demonstrated in an array of microLEDs

    High-Resolution 3D Printing of Freeform, Transparent Displays in Ambient Air

    Get PDF
    Direct 3D printing technologies to produce 3D optoelectronic architectures have been explored extensively over the last several years. Although commercially available 3D printing techniques are useful for many applications, their limits in printable materials, printing resolutions, or processing temperatures are significant challenges for structural optoelectronics in achieving fully 3D-printed devices on 3D mechanical frames. Herein, the production of active optoelectronic devices with various form factors using a hybrid 3D printing process in ambient air is reported. This hybrid 3D printing system, which combines digital light processing for printing 3D mechanical architectures and a successive electrohydrodynamic jet for directly printing transparent pixels of organic light-emitting diodes at room temperature, can create high-resolution, transparent displays embedded inside arbitrarily shaped, 3D architectures in air. Also, the demonstration of a 3D-printed, eyeglass-type display for a wireless, augmented reality system is an example of another application. These results represent substantial progress in the development of next-generation, freeform optoelectronics

    BIOMECHANICAL ANALYSIS A SEQENCE OF ANGULAR VELOCITY AND COORDINATED MUSCLES ACTIVITY DURING BASEBALL HITTING

    Get PDF
    The purpose of this study was to analyse a sequence of rotations and coordinated muscles activities of upper body. Using kinematic and EMG data from 3 recreational university baseball players participating in this study, we computed the angular velocity of trunk, pelvis, bat and trunk-pelvis rotation angle and PMT of upper body muscles. Trunkpelvis rotation angle was 22 ° before the bat-ball contact. The pelvis, trunk, and bat showed a sequence of angular velocity beginning with the hip, followed by the trunk, and end tip of the bat. Additionally, PMT of upper body muscles generated right pectoralis major(1.03 sec.), right external oblique(1.11 sec.), left thoracloumbar fasci(1.12 sec.), left external oblique(1.13 sec.), right latissimus dorsi(1.15 sec.), left latissimus dorsi(1.16 sec.), right thoracloumbar fascia(1.16 sec.), left pectoralis major(1.25 sec.), on at a time during baseball hitting motion. PMT of upper body muscles were related to the shifting and rotating of body segment and this action can be considered the coordinated muscle activities of upper body

    Initial Experience with Laparoendoscopic Single-Site Surgery by Use of a Homemade Transumbilical Port in Urology

    Get PDF
    Purpose: We present our initial experience with laparoendoscopic single-site surgery (LESS) by a single surgeon in the urologic field. Materials and Methods: From May 2009 to April 2010, 30 consecutive patients underwent LESS including seven cases of nephrectomy, five cases of nephroureterectomy with bladder cuff excision, four cases of ureterolithotomy, eight cases of marsupialization, and six cases of varicocelectomy. We performed a retrospective analysis of the medical records of the above patients. The single port was made with a surgical glove and an Alexis?? wound retractor (Applied Medical, Rancho Santa Margarita, CA, USA). The wound retractor was put into the peritoneal space through an umbilical incision, and a laparoscopic triangle was secured by crossing both instruments. All operations were performed by the transperitoneal approach. Results: Mean patient age was 54.8 years. Mean operative time was 171.2??109.1 minutes. Mean estimated blood loss was 265.0??395.5 ml. Mean incision length was 3.2??1.4 cm. Mean length of hospitalization was 5.2??2.9 days. There was one laparoscopic conversion and two open conversions. There were two cases of transient ileus that improved with conservative treatment. Mean visual analogue pain scales on the operative day and first postoperative day were 6.3/10 and 3.1/10, respectively. Conclusions: In our experience, LESS for urologic surgery is feasible, safe, and clinically applicable. We consider the homemade single-port device to be a relatively cost-effective and convenient device. If surgical instruments for LESS and appropriate ports specified for LESS are developed, LESS would be a surgical treatment technique that could be used as an alternative to the conventional types of laparoscopic surgery. ?? The Korean Urological Association, 2010

    Variable Priority Number Control of SPMS for Leisure Ship

    Get PDF
    Abstract: The power system of leisure ship has a character of stand-alone type, so it continuously checks the usable power. Especially, the leisure ship using renewable energy needs to adjust the power consumption of loads according to the usable power. Also, the important loads of leisure ship are different by operation mode. However, current power management system doesnot consider such character. This paper studied load management system of the SPMS(Smart Power Management System) and composed using the smart plug. The SPMS controls the loads depending on a user's pattern and character through variable priority number control. This control algorithm was verified through simulation of assumed user and situation using LabVIEW
    corecore