The phrase 'by either system alone' is correct and usable in written English.
You can use it when expressing that something cannot be done with just one particular system. For example: "The project cannot be completed by either system alone, so we will need to use both."
Two surveillance systems gave a better estimate of influenza hospitalizations in children <5 years of age than either system alone.
Before, the company had only offered the option to identify users by operating system alone, on mobile.
Even if the grid fails, the PV system works in islanded mode to cater the pump load at the permissible limit depending on the generation by PV system alone in the absence of storage systems.
Final removals of the PPCP contaminants were 32.6%, 97.7%, 98.0% and 100% for DEET, PAR, CAF and TCS, respectively, by CW system alone, while 43.3%, 97.5%, 98.2% and 100%, respectively, were achieved by CW-ST system.
There is unlikely to be a situation where ITNs are delivered by one system alone.
Note however that although mating system was the variable explaining most of the variation in polymorphism across plant species, the portion of the total variance in nucleotide diversity accounted by mating system alone is rather modest (less than 10% after phylogenetic relatedness is accounted for).
There is recent empirical interest in whether reductions in molecular genetic variation in selfing compared with outcrossing populations can be explained by mating system alone (because of an up to 50%% reduction in effective population size due to selfing), or if selection for reproductive assurance via population bottlenecks need be invoked (reviewed in Busch and Delph 2012; Wright et al. 2013).
However, while many problems cannot be solved by any one system alone, they can be solved by a combination of these systems.
A contamination with corundum is not detectable by the BonNDTinspect system alone.
Integrative biologist Robert Full of the University of California, Berkeley, suspected that some of the insect's balance-preserving reflexes may be too fast to be controlled by its nervous system alone and are also built into its mechanical structure.
