The phrase "almost efficient and" is correct and usable in written English.
It can be used when describing something that is nearly efficient but not quite there, often in a comparative context.
Example: "The new system is almost efficient and has improved our workflow significantly, but there are still some areas that need optimization."
Alternatives: "nearly efficient and" or "practically efficient and".
In particular, our numerical results demonstrated that Tyler's estimator is an "almost" efficient estimator w.r.t. the CCRB and its estimation accuracy is independent on the value of the shape parameter.
We outline some key points: (i) the great difficulty to obtain accurate numerical results for large values of α (ii) the possibility of virtually optimum schemes is essentially theoretical and requires, in practice, careful experiments; (iii) for strongly convective problems, some second-order explicit schemes are almost as efficient (and less costly) than implicit fourth-order schemes.
Now generators as small as 200 kilowatts are almost as efficient and cheap as the big refinery-size ones.
Petrol cars are now almost as efficient and are much less polluting locally, so scientists say it makes sense to tax diesel cars extra.
LED bulbs face competition from compact fluorescent lights which are almost as energy efficient and cost a lot less.
IN these days when modest bungalows on small lots are replaced by looming mini-mansions, there's something pleasingly efficient and almost virtuous about a home that is small yet well-designed.
By automating most of the RBF mesh deformation, a robust, efficient and almost user-independent mesh deformation method is presented.
Metal foams show efficient and almost isotropic energy absorption during compression making them interesting materials for the design and development of impact resistant components.
Charles John conducted an efficient and almost bloodless campaign, and in August the Norwegians signed the Convention of Moss, whereby they accepted Charles XIII as king but retained the May constitution.
The burial team is efficient and almost jovial.
