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We report the results of searching pulsar-like candidates from theunidentified objects in the $3^{\rm rd}$ Catalog of Hard Fermi-LAT sources(3FHL). Using a machine-learning based classification scheme with a nominalaccuracy of $\sim98\%$, we have selected 27 pulsar-like objects from 200unidentified 3FHL sources for an identification campaign. Using archival data,X-ray sources are found within the $\gamma-$ray error ellipses of 10 3FHLpulsar-like candidates. Within the error circles of the much better constrainedX-ray positions, we have also searched for the optical/infrared counterpartsand examined their spectral energy distributions. Among our short-listedcandidates, the most secure identification is the association of 3FHLJ1823.3-1339 and its X-ray counterpart with the globular cluster Mercer 5. The$\gamma-$rays from the source can be contributed by a population of millisecondpulsars residing in the cluster. This makes Mercer 5 as one of the slowlygrowing hard $\gamma-$ray population of globular clusters with emission $>10$GeV. Very recently, another candidate picked by our classification scheme, 3FHLJ1405.1-6118, has been identified as a new $\gamma-$ray binary with an orbitalperiod of $13.7$ days. Our X-ray analysis with a short Chandra observation hasfound a possible periodic signal candidate of $\sim1.4$ hrs and a putativeextended X-ray tail of $\sim20$ arcsec long. Spectral energy distribution ofits optical/infrared counterpart conforms with a blackbody of $T_{\rmbb}\sim40000$ K and $R_{\rm bb}\sim12R_{\odot}$ at a distance of 7.7 kpc. Thisis consistent with its identification as an early O star as found by infraredspectroscopy.

Searches for Pulsar-like Candidates from Unidentified Objects in the Third Catalog of Hard Fermi-LAT (3FHL) sources with Machine Learning Techniques