Pump Power Ratio Research Articles

Cross-phase modulation induced microcomb generation in the normal-dispersion region.

Microcomb generation in the normal-dispersion region usually requires specially designed microresonators with mode interactions, increasing the complexity of device design and control. Here we demonstrate a novel, to the best of our knowledge, scheme of frequency comb generation by bidirectionally pumping an ordinary normal-dispersion microresonator. The cross-phase modulation from the counter-propagating light reshapes the cavity response, facilitating the emergence of modulational instability for comb initiation. By properly adjusting the pump power ratio and frequency detuning in two directions, frequency combs can be formed at any pumped resonance. The proposed method provides a universal pathway to flexible microcomb generation in the normal-dispersion regime.

Simultaneous realization of high gain and low DMG of four-mode EDFA under bidirectional hybrid-mode pump.

We theoretically and experimentally verify that, the bidirectional hybrid-mode pumping scheme can address the optimization problem of trade-off between high gain and low differential modal gain (DMG) of four-mode erbium-doped fiber amplifier (4M-EDFA), in comparison with traditional both forward and backward hybrid-mode pumping scheme. It is noticed that, when the total pump power is fixed, the bidirectional hybrid-mode pumping scheme can not only achieve higher gain, but also suppress DMG due to different overlap integrals for the forward and backward pumping schemes. The bidirectional hybrid-mode pumped 4M-EDFA is developed with the forward pumping at LP02 mode and the backward pumping at LP21 mode, under a pump power ratio of 30%:70%. Thus, we can achieve an average gain of up to 21.16 dB and a low DMG of 0.43 dB at 1550 nm, and an average gain of up to 20.64 dB with a DMG of less than 1.6 dB over the C-band. In particular, the bidirectional hybrid-mode pumping scheme allows us to tailor the gain characteristics of the few-mode erbium-doped fiber amplifiers (FM-EDFAs), by adjusting the power ratio between forward and backward pumps.

Slowdown of group velocity of light in dual 1480 nm hybrid pump cascade structure of Er3+-doped optical fiber at room temperature

In this paper, a general theory of slow light transmission in dual 1480nm hybrid pump cascade structure of Er3+-doped optical fiber at room temperature is presented. Our objective is to compare the dual 1480nm hybrid pump cascade structure with the 1480nm and 980nm hybrid pump cascade structure in relative modulation attenuation, time delay, fractional delay, group velocity, refractive index, and signal optical loss. Through theoretical calculation, the maximum time delay is increased by 1.111 times and 1.162 times, and the maximum fractional delay is increased by 1.091 times and 1.132 times when the pump power ratio M=0.5 and 0.75. The loss coefficient is reduced to 0.1 when M=1. The results show that compared with the previous research methods, the dual 1480nm hybrid pump cascade structure can obtain larger time delay, fractional delay and smaller loss, which may have important applications for the optimization of optical communication systems.

Influence of restrictor on the thermal-hydraulic performance in manifold microchannel heat sink

Manifold microchannel heat sinks (MMCHSs) are essential in thermal management. Conventional Z-type MMCHS encounter flow maldistribution and large temperature gradients on the heating surface. This work proposes an innovative MMCHS with restrictors to reduce flow maldistribution and compared with other optimization schemes. Through the numerical simulation, we optimize three dimensionless parameters (the width ratio α and length ratio β of the restrictor and inlet-to-outlet width ratio of manifold γ). Introducing the restrictor into the MMCHS can reduce flow maldistribution. In the research scope, the maximum mass flux discrepancy of MMCHS with α = 0.3 decreased from 327.17% to 64.51% compared to MMCHS with α = 1 when the volumetric flow rate is 8.51 mL/min. The reason is that restrictors increase the ratio between pressure drop in microchannels and total pressure drop(Δpc/Δp). Additionally, the coupling effect of the restrictor and γ on thermal-hydraulic in MMCHS are complicated. Therefore, the thermal resistance ratio (Rt/Rt,0), the pumping power ratio (Pp/Pp,0) and performance evaluation criteria (PEC) are taken as references to consider the thermal-hydraulic performance of MMCHS comprehensively. The results display that the MMCHS with α = 0.5– 0.6, β = 0.4 and γ = 0.8– 1 can further control the synchronization of Rt/Rt,0 and Pp/Pp,0 at about 0.75. The PEC values are all greater than 1.59.

Bidirectional Cladding-Pumped Multicore EDFA and its Optimization for Energy Efficiency by Tuning Pump Condition

This work investigates the feasibility of improving the energy efficiency of a cladding-pumped multicore (MC) EDFA by utilizing bidirectional (BD) pumping. We combined a conventional forward-cladding-pumped MC-EDFA with backward cladding pumping and tuned the pump-gain characteristics and gain shape by controlling the optical pump power ratio of its forward and backward pumps. Since EDFAs have wavelength dependence, output power equalization by each wavelength channel is extremely important for amplifying the wavelength division multiplexing (WDM) signal. The standard method of current equalization is to adjust the attenuation by the output power of each wavelength channel. The main issue with the current standard equalization is the indispensable optical power loss caused the reduced optical amplification efficiency of the EDFA. Our previous work demonstrated that the optical power loss due to equalization can be reduced by controlling the optical power ratio of the forward and backward pumps. This leads to improved energy efficiency of the signal amplification and equalization of both the WDM and spatial division multiplexing (SDM). <p xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">In this paper, we report our detailed investigation into the tuning amplification characteristics of the BD-MC-EDFA. Our main focus was the gain, noise figure (NF), and gain shape of a 7-core BD-MC-EDFA prototype when forward and backward optical pump power was changed. Under 8 W of total optical pump power, the percentage of 60% forward cladding optical pump power was found to be optimal for efficiency considering the minimum output optical power loss due to equalization. This condition translates into a 1.7% pump conversion efficiency (PCE) improvement, which corresponds to a 24% reduction of the total optical pump power compared to conventional MC-EDFA with only forward cladding pumping. Although the NF deteriorated by 1.0 dB in wavelength average in the 4.5-THz signal bandwidth in exchange for the efficiency improvement, degradation of the 34.2-GBaud polarization multiplexed 16 quadrature amplitude modulation (PM-16QAM) signal amplified by the BD-MC-EDFA operated under the optimized condition was negligible.

Performance Comparison of Helium and sCO2 as Coolants for Modular Finger-Type Divertors

Several studies at the Georgia Institute of Technology have evaluated the thermal and fluids performance of the helium-cooled modular divertor with multiple jets (HEMJ) over the past decade. This finger-type divertor was studied both experimentally at nearly prototypical conditions and numerically at fully prototypical operating conditions using experimentally validated simulations. Recently, supercritical carbon dioxide (sCO2) has been studied as the primary coolant in power cycles and other applications in various systems, in part because CO2 achieves the high densities typical of supercritical fluids at relatively low temperatures and pressures, with a critical point of (7.38 MPa, 31°C). This density makes it possible to realize very compact and efficient sCO2 power cycles. The feasibility of sCO2 as a coolant for plasma-facing components, specifically the divertor, was therefore evaluated as part of the Fusion Energy System Studies design study activities. This work compares the thermal-fluid performance of helium and sCO2 in the HEMJ divertor geometry using numerical simulations at prototypical conditions: inlet temperatures Ti = 600°C to 700°C, pressures p ≈ 10 MPa, and steady-state incident heat fluxes on the tile q″ < 17 MW/m2. The performance is quantified here as the maximum heat flux that can be accommodated by the plasma-facing tile, the pumping power fraction, defined as the ratio of the coolant pumping power to the incident thermal power, and the operating stress limits based on ASME pressure vessel criteria. As expected, helium requires lower mass flow rates and pumping power fractions within imposed maximum temperature limits for the HEMJ pressure boundary. However, it also appears that neither helium nor sCO2 can remove 10 MW/m2 of incident heat flux while meeting ASME pressure vessel criteria. Finally, the numerical modeling reveals that sCO2 may remove slightly higher incident heat fluxes than helium due to the imposed stress limits due to the sCO2 coolant resulting in smaller local temperature gradients, albeit at a considerably higher pumping power fraction.

Effect of non-uniform wall corrugations on laminar convective heat transfer through rectangular corrugated tube by using graphene nanoplatelets/MWCN hybrid nanofluid

Hybrid nanofluids and non-uniform wall corrugations have been reported to enhance convective heat transfer, which is not yet fully explored. In this study, the heat transfer efficacy of non-uniform wall corrugations on laminar convective heat transfer through a rectangular corrugated tube by using a hybrid nanofluid is investigated. Three different non-uniform wall corrugations; gradually increasing wall corrugation (GIWC), gradually decreasing wall corrugation (GDWC) and periodic wall corrugation (PWC) are investigated and compared with uniform wall corrugation (UWC). The applied hybrid nanofluid is a mixture of graphene nanoplatelets (GnP) and multi-walled carbon nanotubes (MWCN) with water, wherein the volume fractions of nanoparticles are 0.1%, 0.15%, and 0.2%. The computation is conducted under 2000 kW/m2 heat flux conditions on the heated surface of the corrugated wall with the Reynolds number in the range of 500–2000. The heat transfer efficacy and required pumping power are investigated for different wall corrugations and Reynolds numbers. The developed numerical model was validated with experimental studies from the published literature on different corrugated conduits. The computation results indicate that non-uniform wall corrugations GIWC, GDWC, and PWC provided better performance compared to uniform corrugation UWC. The average Nusselt number is the highest for PWC compared to others. At a constant Reynolds number 1000, the heat transfer was enhanced by an overall 15.61% for GDWC, 18.70% for GIWC, and 21.16% for PWC compared to UWC. In addition, PWC provided the highest increase in the pumping power requirement compared to others. At a constant Reynolds number 1000, the pumping power ratio is 1.37 for GDWC, 1.47 for GIWC, and 1.54 for PWC compared to UWC. GnP/MWCN-water hybrid nanofluid with a 0.2% volume fraction provided the highest enhancement in heat transfer compared to pure water. For PWC configuration, mixing nanoparticle volume fractions from 0.1% to 0.2%, the Nusselt number increases from 6.66% to 23.75%,while the pumping power ratio increases from 1.24 to 1.39 compared to water. It can be concluded that further experimental investigation is critical to validate the implementation of non-uniform wall corrugation for enhancing the thermal performance of rectangular corrugated tubes.

Effect of plate spacing and inclination angle over the thermal performance of plate heat exchanger working with novel stabilized polar solvent-based silicon carbide nanofluid

In this work, the overall thermal performance of a commercial corrugated plate heat exchanger has been conducted for the first time by varying the three different plate corrugated angles (30°, 45°, 60°) and variable plate spacing (from 5 mm to 20 mm) working with polar solvent-based novel Silicon carbide (SiC)/DI Water nanosuspension as a coolant by focusing potential industrial application. This study aimed to identify the enhancement in thermal performance of plate heat exchanger by evaluating its overall heat transfer coefficient, pressure drop, pumping power, and exergetic efficiency by utilizing SiC/DI water nanofluid of varying volume concentration (0.20 %, 0.40 %, 0.60 %, 0.80 %, 1.00 %, 1.20 %, and 1.40 %) at ambient condition (T0 = 27 ° C), and fixed volumetric flow rate (3 L/min) for both (nanofluid and milk) sides. From the experimental results, the optimum volume concentration for the coolant was found as 0.60 %, which yields a significant enhancement in the overall heat transfer coefficient ratio by approximately 51 %, 42 %, and 38 % for 60°, 45°, and 30° corrugated plate angle respectively. The significant enhancement for 0.6 % of optimum volume concentration and 5 mm plate spacing has been reported as the best possible option at which the pumping power ratio, performance index ratio, and exergetic efficiency ratio attained the highest enhancements.

650 W All-Fiber Single-Frequency Polarization-Maintaining Fiber Amplifier Based on Hybrid Wavelength Pumping and Tapered Yb-Doped Fibers

Based on hybrid wavelength pumping and tapered Yb-doped fibers (T-YDFs), a 650 W all-fiber single-frequency polarization-maintaining fiber amplifier was demonstrated experimentally at 1030 nm. Different pump power ratios in the T-YDF-based power-amplifier stage were proposed to investigate their influence on the transverse mode instability (TMI) effect. The highest TMI threshold was obtained when the pump power ratio of 940 nm to 976 nm was 1:4.4. A measured M2 factor of 1.7 and a polarization extinction ratio of 14 dB at the maximum output power were obtained. To the best of our knowledge, these results exhibit the highest output power of any all-fiber single-frequency polarization-maintaining fiber amplifiers created up to now.

Transient thermal effect analysis and laser characteristics of novel Tm: LuYAG crystal

Based on the actual working environment, the thermal model of novel Tm: LuYAG crystal is established, and the transient thermal effect of pulsed laser diode single-end pumped Tm: LuYAG laser under different spot radius, pump power, repetition frequency, pulse width and duty ratio are simulated, analyzed, and discussed theoretically. The output characteristics of pulsed-LD end-pumped Tm: LuYAG laser are achieved and analyzed at different repetition frequencies and duty ratios experimentally. At repetition frequency of 10 Hz, 100 Hz, 1000 Hz and duty ratio of 50 %, the maximum output energy is 724 mJ, 70 mJ, 6.36 mJ, with the slope efficiency is 39.4 %, 38.2 % and 35.5 %, respectively. Moreover, at repetition frequency of 10 Hz and duty ratio of 75 %, the maximum output energy of 900 mJ is achieved with slope efficiency of 34.6 %. The central wavelength of Tm: LuYAG laser is measured to be 2018.96 nm, and the beam quality is Mx2 = 1.96, My2 = 1.98. To our knowledge, it is the first time to analyze the transient thermal effect of Tm: LuYAG crystal pumped by pulsed laser diode in detail. As far as we know, this is the maximum output energy based on the novel Tm: LuYAG crystal.

Heat transfer enhancement using double taper microchannel

A three-dimensional numerical study on the combined effect of height as well as width tapering on the thermal performance of double taper microchannel is presented in this paper. The channel inlet width is considered as 300 µm, taper ratio on sidewalls and bottom wall are varied from 0 to 1 and 1 to 3.9, respectively. The thermal resistance ratio, average bottom wall temperature, temperature difference ratio, and pumping power ratio of the channel are evaluated for various flow rates, height, and width tapering. Results showed higher reduction of wall temperature with combined effect height as well as width tapering compared with straight channel. The optimal size of the micro channel to minimize the pumping power and average wall temperature on the constraint of heat flux and footprint area is found. The reduction in average bottom wall temperature is 17.34%, and pumping power ratio is 0.44 (56% power reduction) noted, respectively, at Reynolds number 340. Finally, optimal dimension of double taper microchannel is evaluated for better thermo-hydraulic performance.

Convective Heat Transfer and Pumping Power Analysis of MWCNT + Fe3O4/Water Hybrid Nanofluid in a Helical Coiled Heat Exchanger with Orthogonal Rib Turbulators

Utilizing nanofluids in heat exchangers can lead to improved thermal performance. Nanofluids with suspended carbon nanotubes are specifically desirable in thermal systems because of their unique capabilities. In this study, convective heat transfer and required pumping power are studied simultaneously for a helical coiled heat exchanger with laminar water flow while incorporating 0.1 and 0.3 percent volume fraction of the hybrid nanofluid MWCNT + Fe3O4/water. Two different geometries of bare and ribbed tubes are used for the heat exchanger part. The ribs are chosen to be orthogonal, i.e., 90° with respect to the inclined ones. Three different Reynolds numbers are selected for investigation, all in laminar flow regime based on the non-dimensional M number defined in coiled tubes. Computational fluid dynamics is used to study thermal and fluid behavior of the problem. The convective heat transfer coefficient can serve as a criterion to measure the effectiveness of utilizing nanofluids in heat exchangers by taking the pressure drop and pumping power of the system into consideration. Finally, the artificial neural network curve fitting tool of MATLAB is used to make a good fit in the data range of the problem. It is shown that for most cases of the study, the pumping power ratio is less than 1 that can be considered appropriate from energy consumption viewpoint.

Heat Transfer Capability of Ionanofluids for Heat Transfer Applications

Ionanofluids are mixtures of ionic liquid and solid particles with enhanced thermo-physical properties. Using the properties of these ionanofluids (thermal conductivity, dynamic viscosity, specific heat, and density), a comprehensive analysis concerning their heat transfer capability was performed. Two nanomaterials, silicon carbide (SiC) and graphene dispersed in 1-hexyl-3-methylimidazolium tetrafluoroborate ([Hmim]SF4) were studied. Different equations (figures of merit) as a base of comparison for laminar and turbulent flows were used. The effects of concentration and temperature on the pumping power ratio were theoretically investigated. The results indicated that the studied ionanofluids can contribute to the enhancement of thermal performance, especially in laminar flow.

A two-phase simulation for analyzing thermohydraulic performance of Cu–water nanofluid within a square channel enhanced with 90° V-shaped ribs

A numerical investigation is conducted by implementing a two-phase model based on the mixture theory with the aim of assessing the attributes associated with the thermohydraulic performance of the Cu–water nanofluid through a square channel equipped by the 90° V-shaped ribs. The ribs are attached on the top and bottom walls of the channel with different rib heights and rib pitches. It is observed that the average heat transfer coefficient significantly enhances with the volume fraction increment such that it enhances around 22.7% with increasing the volume fraction from 1 to 2% at rib pitch of 100 mm and rib height of 2.5 mm. The presence of the ribs considerably intensifies the flow mixing and disrupts the thermal boundary layer by means of generating the four counter-rotating vortices. In addition, employing the ribs with greater heights as well as smaller pitches augments the heat transfer coefficient as well as Nusselt number, such that the Nusselt number increases about 28.3% when the rib height increases from 2.5 to 7.5 mm in the condition in which the rib pitch is 50 mm. The Figure of Merit (FoM), which shows the fraction of the convective heat transfer coefficient ratio to the pumping power ratio for the case of using the nanofluid compared to the water, is much higher than 1, which demonstrates the benefit of employing the nanofluid rather than the water. Furthermore, increasing the volume fraction results in a greater FoM, which manifests the greater merit of using the nanofluid at higher concentrations.

Thermal performance enhancement of automobile radiator using water-CuO nanofluid: an experimental study

In the present paper, the effect of water-CuO nanofluid on the radiator heat transfer of an automobile, Peugeot 405 XU7 engine type is investigated experimentally. The experiments are carried out for the radiator water (water-ethylene glycol with a volume fraction of 80-20, respectively) as a base fluid and water-CuO nanofluid with the volume fraction of 0.5% and 1%. Sodium Dodecyl Sulfate (SDS) is used to increase the stability of nanofluid. The results demonstrated that a significant increase in the heat transfer of the engine to the environment is obtained by adding CuO nanoparticles to the base fluid. For nanofluid volume fraction of 0.5 and 1% for a mass flow rate of 30 liters per minute, the heat transfer rate enhances 3% and 6.9%, respectively, in comparison with the base fluid. Although convective heat transfer coefficient increased by increasing the nanofluid volume fraction, the experiments showed that this coefficient increases with the mass flow rate up to 20 liters per minute and then decreases with the mass flow rate. Besides, the radiator pressure drop increases by increasing of the pressure of nanofluid. The results revealed that the ratio of heat transfer and pump power (merit parameter) decreases as the nanofluid pressure increases

Heat transfer and presser drop of copper oxide–thermal oil in upward single-phase flow in inclined microfin tube under constant wall temperature

The effects of using copper oxide–thermal oil on convective heat transfer and pressure drop in an upward flow in an inclined microfin tube is studied experimentally in this research project. The flow regime and wall temperature are laminar and constant, respectively. The effects of nanofluid, Graetz number, Prandtl number and positive inclination angles on convective heat transfer augment moderately with the boom in nanoparticles mass concentration. The result shows that the forced heat transfer and Darcy friction factor increase with the increment of mass nanoparticle concentration, Reynolds number and inclination angle. The ratio of Darcy friction factor increases up to 64% in microfin tube. The Nusselt number boosts to reach 62 when mass nanoparticle concentration and inclination angle were 1.5% and 30o, respectively. Two correlations are advised to estimate Nusselt number and Darcy friction factor in upward single-phase flow in microfin tube under constant wall temperature and laminar flow in microfin pipe. The maximum aberrations of Nusselt number and Darcy friction factor are 20% and 18%, respectively, which are admissible to predict experimental data. Accompaniment of heat transfer ratio with pumping power ratio is presented in this paper. If the increment of pressure drop is more than heat transfer enhancement, it will not be appropriate to use CuO-thermal oil, inclination angles and microfin tube. The maximum FOM is 59% which is calculated with 1.5% nanoparticle mass concentration and inclination angle of 60o at Prandtl number of 349.

Co-amplification: An efficient spectral beam combination approach for high power, closely separated dual wavelength dye laser systems

Characteristics of an efficient spectral beam combination of two dye laser beams with wavelength difference of less than 10 nm are presented. Two dye laser oscillator beams were spatially and temporally combined with reduced losses before their co-amplification in a common power amplifier. Yellow and green beams of 9 kHz (pulse repetition rate) copper vapour laser (CVL) Master Oscillator Power Amplifier (MOPA) Chain were utilised to pump Rh 101 dye laser oscillators and DCM dye common amplifier respectively. The characteristics of green beam pumped DCM dye common amplifier were studied at various pump power and input power ratios. Combination losses for this configuration were 40% relative to individually amplified configuration. Input–output characteristics of the common amplifier were determined at various input power ratios. Composite dual wavelength dye laser beam having total power of 7.35W at 38.4 W pump power with extraction efficiency 16.5% was demonstrated.

Suitability of various heat transfer fluids for high temperature solar thermal systems

In recent years there is a huge interest in developing high temperature, solar thermal systems for power generation. Selection of suitable heat transfer fluid is an important requirement for these applications. This paper presents a comparative study between various heat transfer fluids suitable for high temperature solar thermal systems. The comparison is made on the basis of equal heat transfer rate, temperature rise of the heat transfer fluid and pressure drop per unit length in a typical solar absorber tube. Using simple friction factor and heat transfer correlations, equations for diameter ratio, heat transfer coefficient ratio, area ratio, length ratio, fluid pumping power ratio and fluid inventory cost ratio are obtained for various fluids, taking supercritical CO2 as the reference fluid. Figure of merit (FOM) ratio is also calculated using available equations. It is observed that liquid heat transfer fluids and molten salts offer better performance in the intermediate temperature range of around 150–550 °C. However, currently gaseous fluids (e.g. CO2 or He) are the only alternatives for temperatures beyond 550 °C. Supercritical CO2 offers the best performance in terms of cost of fluid inventory, which can be a major consideration in large output solar fields.

Dual-wavelength-pumped Tm3+-doped ZBLAN fiber MOPA at 813 nm

We report a dual-wavelength-pumped (1220 nm + 1050 nm) Tm3+-doped ZBLAN fiber master oscillator power amplifier (MOPA) system at 813 nm for the lattice laser of the Sr optical lattice clock (OLC). Since the photodarkening effect of the Tm3+-doped fiber is more serious in the 800 nm region, it was suppressed by applying real-time photobleaching with a 532 nm laser for obtaining stable output. We also investigated the dependence of conversion efficiency on the launched pump power ratio (P1220 nm/P1220+1050 nm) and found that the maximum conversion efficiency of 50% was obtained from the pump power ratio of 41%. By installing real-time photobleaching and dual-wavelength pumping, our MOPA system generated the maximum output power of 1.95 W with slope efficiency of 48%, which is the highest output power at around 810 nm from fiber laser sources, to the best of our knowledge.

Numerical optimization of design parameters for a modified double-layer microchannel heat sink

In the present work the multi-objective genetic algorithm is employed to optimize the design variables in a double-layer microchannel heat sink. The design matrix is formulated with Latin hypercube sampling and the model approximation is implemented with response surface approximation to reduce the computing time. The design variables for optimization are the relative axial ridge length (Xi) from 0.4 to 1.4, the relative transverse ridge length (Yi) from 0.4 to 0.9, the relative channel length ratio (Li) from 0.2 to 1, and the relative flow rate ratio (σ) from 0.25 to 0.75, respectively. The objective functions are λR (ratio of the thermal resistance of the modified case over base case) and λP (ratio of the total pumping power of the modified case over base case), respectively. The Pareto optimal solutions are extracted and depicted tradeoff between the two objective functions, thus providing a principal understanding into the design variables and allowing autonomy of selection among the optimal solutions. Total 135 Pareto optimal solutions are extracted by using the K-means clustering. Six Pareto optimal combinations (POCs) named as POC – A, POC – B, POC – C, POC – D, POC – E, and POC – F are selected for the comparison of designs. The best design for the heat transfer performance is POC – A (Xi = 0.4003, Yi = 0.4481, Li = 0.6378, σ = 0.2504) with 37.34% lower λR than that for the POC-F, while the best design for the pumping power is POC – F (Xi = 0.4149, Yi = 0.4081, Li = 0.6544, σ = 0.2515) with 96.51% lower λP than that for the POC-A.