다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Fibre lasers in the mid-infrared regime are useful for a diverse range of fields, including chemical and biomedical sensing, military applications and materials processing. This Review summarizes the different rare-earth cations and host materials used in mid-infrared fibre laser technology, and discusses the future applications and challenges for the field.

Towards high-power mid-infrared emission from a fibre laser

Infrared (2–12 μm) solid-state laser sources: a review

Fiber lasers have seen progressive developments in terms of spectral coverage and linewidth, output power, pulse energy, and ultrashort pulse width since the first demonstration of a glass fiber laser in 1964. Their applications have extended into a variety of fields accordingly. In this paper, the milestones of glass fiber laser development are briefly reviewed and recent advances of high-power continuous wave, Q-switched, mode-locked, and single-frequency fiber lasers in the 1, 1.5, 2, and 3 μm regions and their applications in such areas as industry, medicine, research, defense, and security are addressed in detail.

Fiber lasers and their applications [Invited]

In this review we discuss the application of laser-induced breakdown spectroscopy (LIBS) to the problem of detection of residues of explosives. Research in this area presented in open literature is reviewed. Both laboratory and field-tested standoff LIBS instruments have been used to detect explosive materials. Recent advances in instrumentation and data analysis techniques are discussed, including the use of double-pulse LIBS to reduce air entrainment in the analytical plasma and the application of advanced chemometric techniques such as partial least-squares discriminant analysis to discriminate between residues of explosives and non-explosives on various surfaces. A number of challenges associated with detection of explosives residues using LIBS have been identified, along with their possible solutions. Several groups have investigated methods for improving the sensitivity and selectivity of LIBS for detection of explosives, including the use of femtosecond-pulse lasers, supplemental enhancement of the laser-induced plasma emission, and complementary orthogonal techniques. Despite the associated challenges, researchers have demonstrated the tremendous potential of LIBS for real-time detection of explosives residues at standoff distances.

Laser-induced breakdown spectroscopy for detection of explosives residues: a review of recent advances, challenges, and future prospects

We report a monolithic ~ 0.95 mJ pulsed fiber laser in 2 µm regime with transform-limited linewidth and 10-100 ns pulse width. This MOPA-based pulsed fiber laser is based on highly Tm-doped germanate fibers.

mJ-level 2µm transform-limited nanosecond pulses based on highly Tm-doped germanate fibers

A space-based 2-micron coherent Doppler lidar can have a significant impact on climate research and numerical weather forecasting. This paper describes the key challenges of deploying such an instrument in space, and provides a status of the technology development activities.

2-micron coherent Doppler lidar for space-based global wind field mapping

For space-based lidar applications, conductively cooled lasers have been identified as a critical technology for high energy, 2-micron laser transmitter. Effective thermal management is a challenge for high-energy, 2-micon lasers. In this paper, the design of a totally conductively cooled, diode pumped, 2-micron laser amplifier is presented. Based on the successful testing of a conductively cooled oscillator, concepts for a laser amplifier were developed. The newly designed amplifier consists of a 40 mm long Ho:Tm: LuLF rod being pumped by 4 banks of 5-radially arranged diode lasers totaling 80W pump power. Optical and thermal studies for the amplifier head are presented and discussed. Currently, the design of the amplifier head is being integrated into a complete amplifier subsystem for a conductive cooled Master Oscillator Power Amplifier (MOPA) laser.

Design of a totally conductively cooled diode-pumped 2μm-laser amplifier

Sarcopenia is a serious public health concern among older adults worldwide. Exercise is the most common intervention for sarcopenia. This study aimed to compare the effectiveness of different exercise types for older adults with sarcopenia.

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/jcsm.13225

Exercise for sarcopenia in older people: A systematic review and network meta‐analysis

Early concepts to globally measure vertical profiles of vector horizontal wind from space planned on an orbit height of 525 km, a single pulsed coherent Doppler lidar system to cover the full troposphere, and a continuously rotating telescope/scanner that mandated a vertical line of sight wind profile from each laser shot. Under these conditions system studies found that laser pulse energies of approximately 20 J at 10 Hz pulse repetition rate with a rotating telescope diameter of approximately 1.5 m was required. Further requirements to use solid state laser technology and an eyesafe wavelength led to the relatively new 2-micron solid state laser. With demonstrated pulse energies near 20 mJ at 5 Hz, and no demonstration of a rotating telescope maintaining diffraction limited performance in space, the technology gap between requirements and demonstration was formidable. Fortunately the involved scientists and engineers set out to reduce the gap, and through a combination of clever ideas and technology advances over the last 15 years, they have succeeded. This paper will detail the gap reducing factors and will present the current status.

/pdf/requirements-and-technology-advances-for-global-wind-3ivnmcxkif.pdf

Jirong Yu

Papers

mJ-level 2µm transform-limited nanosecond pulses based on highly Tm-doped germanate fibers

2-micron coherent Doppler lidar for space-based global wind field mapping

Design of a totally conductively cooled diode-pumped 2μm-laser amplifier

Exercise for sarcopenia in older people: A systematic review and network meta‐analysis

Requirements and Technology Advances for Global Wind Measurement with a Coherent Lidar: A Shrinking Gap