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Ping Gui

Publications and source records attributed to Ping Gui.

7 recordsLinked to original sources
PubMed2006

2 Gbit/s 0.5 microm complementary metal-oxide semiconductor optical transceiver with event-driven dynamic power-on capability.

A 2 Gb/s0.5 microm complementary metal-oxide semiconductor optical transceiver designed for board- or backplane level power-efficient interconnections is presented. The transceiver supports optical wake-on-link (OWL), an event-driven dynamic power-on technique. Depending on external events, the transceiver resides in either the active mode or the sleep mode and switches accordingly. The active-to-sleep transition shuts off the normal, gigabit link and turns on dedicated circuits to establish a low-power (approximately 1.8 mW), low data rate (less than 100 Mbits/s) link. In contrast the normal, gigabit link consumes over 100 mW. Similarly the sleep-to-active transition shuts off the low-power link and turns on the normal, gigabit link. The low-power link, sharing the same optical channel with the normal, gigabit link, is used to achieve transmitter/receiver pair power-on synchronization and greatly reduces the power consumption of the transceiver. A free-space optical platform was built to evaluate the transceiver performance. The experiment successfully demonstrated the event-driven dynamic power-on operation. To our knowledge, this is the first time a dynamic power-on scheme has been implemented for optical interconnects. The areas of the circuits that implement the low-power link are approximately one-tenth of the areas of the gigabit link circuits.

Journal Article↗
PubMed2005

Power-efficient dual-rate optical transceiver.

A dual-rate (2 Gbit/s and 100 Mbit/s) optical transceiver designed for power-efficient connections within and between modern high-speed digital systems is described. The transceiver can dynamically adjust its data rate according to performance requirements, allowing for power-on-demand operation. Dynamic power management permits energy saving and lowers device operating temperatures, improving the reliability and lifetime of optoelectronic-devices such as vertical-cavity surface-emitting lasers (VCSELs). To implement dual-rate functionality, we include in the transmitter and receiver circuits separate high-speed and low-power data path modules. The high-speed module is designed for gigabit operation to achieve high bandwidth. A simpler low-power module is designed for megabit data transmission with low power consumption. The transceiver is fabricated in a 0.5 microm silicon-on-sapphire complementary metal-oxide semiconductor. The VCSEL and photodetector devices are attached to the transceiver's integrated circuit by flip-chip bonding. A free-space optical link system is constructed to demonstrate correct dual-rate functionality. Experimental results show reliable link operation at 2 Gbit/s and 100 Mbit/s data transfer rates with approximately 104 and approximately 9 mW power consumption, respectively. The transceiver's switching time between these two data rates is demonstrated as 10 micros, which is limited by on-chip register reconfiguration time. Improvement of this switching time can be obtained by use of dedicated input-output pads for dual-rate control signals.

Journal Article↗
PubMed2005

Performance-based adaptive power optimization for digital optical interconnects.

Optical links are traditionally set to transmit maximum power for worst-case loss and consequently to dissipate more power than is required. We describe a technique to minimize power consumption based on the measured bit-error rate (BER) of the link. This technique uses a novel power-negotiation algorithm that optimizes the link power setting to achieve minimum power dissipation for a target BER. A 0.5 microm complementary metal-oxide semiconductor optical transceiver chip was fabricated, and a free-space optical interconnect system was built for validation. The results showed that the algorithm was able to find the optimum power settings for the VCSELs for a target BER and to account for dynamic changes such as variation in the optical loss in the system.

Journal Article↗
PubMed2005

[The clinical study of multi-slice helical CT three-dimensional reconstruction in the sphenopalatine foramen].

OBJECTIVE: Used multi-slice helical CT to observe the reconstruction of the surface structure of nasal lateral wall "sphenopalatine foramen" and compared with anatomical specimens to verify the dependability of 3D data. METHOD: The position, shape, size and their correlational data of sphenopalatine foramen of 5 cadaver heads (10 sides) in adults fixed with formalin were dissected and measured. RESULT: Multi-slice helical CT has more rapid speed of 3D reconstruction and clearer imaging. The technique of Shade surface display and Volume rendering can give very clear structure of nasal lateral wall "sphenopalatine foramen". The 3D data makes no statistic difference with anatomical measurement. The 3D data can instruct the clinic directly. CONCLUSION: Multi-slice helical CT three-dimensional reconstruction can be used to orientation of surgery.

Adult↗
PubMed2005

Distribution characteristics of ammonia-oxidizing bacteria in the Typha latifolia constructed wetlands using fluorescent in situ hybridization (FISH).

A molecular biology method, fluorescent in situ hybridization (FISH), in which the pre-treatment was improved in allusion to the media of the constructed wetlands (CW), e.g. the soil and the grit, was used to investigate the vertical distribution characteristics of ammonia-oxidizing bacteria (AOB) quantity and the relation with oxidation-reduction potential (ORP) in the Typha latifolia constructed wetlands under three different loadings in summer from May to September. Results showed that the quantity of the AOB decreased in the Typha latifolia CW with the increase of vertical depth. However, the AOB quantity was 2-4 times the quantity of the control in the root area. Additionally, ORP in the rhizosphere was found to be higher than other areas, which showed that Typha latifolia CW was in an aerobic state in summer when using simulated non-point sewage at the rural area of Taihu Lake in China and small town combined sewage.

Bacteria↗
PubMed2004

[The study of microdissection of endoscopic transnasal surgery in the sphenopalatine foramen].

OBJECTIVE: To provide anatomy evidence for endoscopic transnasal surgery in the sphenopalatine foramen by measuring and dissecting corpses. METHOD: The position, shape, size and their correlational data of sphenopalatine foramen of 40 sides skulls in adults were measured. RESULT: Classification of the sphenopalatine foramen were as three types: I 35%; II 5%; III 60%. The mean distance from upper edge of the sphenopalatine foramen to the base of the sphenopalatine sinus was male (1.75 +/- 1.10) mm, female (1.13 +/- 0.55) mm, and to the apertura sphenopalatine sinus was male (9.80 +/- 3.27) mm, female (8.30 +/- 3.45) mm. The mean distance from the posterior edge of the sphenopalatine foramen to the rhinopharynx was male (11.12 +/- 3.30) mm, female (10.85 +/- 3.12) mm. The mean distance from the anterior edge of the sphenopalatine foramen to the apertura maxillaris was male (18.50 +/- 6.80) mm, female (14.57 +/- 5.07) mm, and to the apex of nose was male (69.54 +/- 6.98) mm, female (66.57 +/- 5.07) mm, and to the nasospinale was male (56.69 +/- 5.70) mm, female (53.25 +/- 8.80) mm. The horizontal diameter of the sphenopalatine foramen was female (4.61 +/- 1.80) mm, male (5.12 +/- 2.05) mm. The vertical diameter was male (5.37 +/- 2.67) mm, female (0.35 +/- 0.07) mm. The surface diameter of the sphenopalatine artery and nerves was male (2.12 +/- 0.66) mm, female (1.61 +/- 0.70) mm, and male (0.65 +/- 0.49) mm, female (0.35 +/- 0.07) mm. The mean angle from the sphenopalatine foramen to the horizontal plate of palatine bone was male (22.83 +/- 4.71) degrees, female (22.73 +/- 3.81) degrees. Nasal lateral walls were controlled by lateral posterior nasal arteries and nerves, which were classified into three types: I 70%, II 20%, III 10%. CONCLUSION: The observation and survey about the sphenopalatine foramen will supply clinic with anatomy homological.

Adult↗