documentclass[twocolumn]{article}

usepackage[paper=a5paper,margin=1cm]{geometry}% Just for this example

usepackage{hyperref}
defUrlBreaks{do/do-}

begin{document}

Default bibliography:

begin{thebibliography}{X}
  bibitem{abc0}
  Adventech B+B SmartWorx. {itshape Smart IoT Technologies for Adaptive
  Traffic Management Using a Wireless Mesh Sensor Network.} 19 November 2014.
  http://advantech-bb.com/smart-iot-technologies-for-adaptive-traffic-management-using-a-wireless-mesh-sensor-networks/.
  Accessed: 15 October 2017.

  bibitem{def0}
  Elsevier. {itshape Data-driven smart-city-enabled traffic system modeling,
  analysis and optimization.}
  https://www.journals.elsevier.com/transportation-research-part-c-emerging-technologies/call-for-papers.
  Accessed: 15 October 2017.
end{thebibliography}

newpage

First alternative:

begin{thebibliography}{X}
  raggedright
  bibitem{abc1}
  Adventech B+B SmartWorx. {itshape Smart IoT Technologies for Adaptive
  Traffic Management Using a Wireless Mesh Sensor Network.} 19 November 2014.
  http://advantech-bb.com/smart-iot-technologies-for-adaptive-traffic-management-using-a-wireless-mesh-sensor-networks/.
  Accessed: 15 October 2017.

  bibitem{def1}
  Elsevier. {itshape Data-driven smart-city-enabled traffic system modeling,
  analysis and optimization.}
  https://www.journals.elsevier.com/transportation-research-part-c-emerging-technologies/call-for-papers.
  Accessed: 15 October 2017.
end{thebibliography}

newpage

Second alternative:

begin{thebibliography}{X}
  bibitem{abc2}
  Adventech B+B SmartWorx. {itshape Smart IoT Technologies for Adaptive
  Traffic Management Using a Wireless Mesh Sensor Network.} 19 November 2014.
  url{http://advantech-bb.com/smart-iot-technologies-for-adaptive-traffic-management-using-a-wireless-mesh-sensor-networks/}.
  Accessed: 15 October 2017.

  bibitem{def2}
  Elsevier. {itshape Data-driven smart-city-enabled traffic system modeling,
  analysis and optimization.}
  url{https://www.journals.elsevier.com/transportation-research-part-c-emerging-technologies/call-for-papers}.
  Accessed: 15 October 2017.
end{thebibliography}

newpage

Third alternative:

begin{thebibliography}{X}
  bibitem{abc3}
  Adventech B+B SmartWorx. {itshape Smart IoT Technologies for Adaptive
  Traffic Management Using a Wireless Mesh Sensor Network.} 19 November 2014.
  href{http://advantech-bb.com/smart-iot-technologies-for-adaptive-traffic-management-using-a-wireless-mesh-sensor-networks/}{http://advantech-bb.com/}.
  Accessed: 15 October 2017.

  bibitem{def3}
  Elsevier. {itshape Data-driven smart-city-enabled traffic system modeling,
  analysis and optimization.}
  href{https://www.journals.elsevier.com/transportation-research-part-c-emerging-technologies/call-for-papers}{http://www.journals.elsevier.com/}.
  Accessed: 15 October 2017.
end{thebibliography}

newpage

Fourth alternative:

begin{thebibliography}{X}
  bibitem{abc4}
  Adventech B+B SmartWorx. {itshape Smart IoT Technologies for Adaptive
  Traffic Management Using a Wireless Mesh Sensor Network.} 19 November 2014.

  href{http://advantech-bb.com/smart-iot-technologies-for-adaptive-traffic-management-using-a-wireless-mesh-sensor-networks/}{http://advantech-bb.com/}

  Accessed: 15 October 2017.

  bibitem{def4}
  Elsevier. {itshape Data-driven smart-city-enabled traffic system modeling,
  analysis and optimization.}

  href{https://www.journals.elsevier.com/transportation-research-part-c-emerging-technologies/call-for-papers}{https://www.journals.elsevier.com/}

  Accessed: 15 October 2017.
end{thebibliography}

newpage

Fifth alternative:

begin{thebibliography}{X}
  bibitem{abc5}
  Adventech B+B SmartWorx. {itshape Smart IoT Technologies for Adaptive
  Traffic Management Using a Wireless Mesh Sensor Network.} 19 November 2014.
  href{http://advantech-bb.com/smart-iot-technologies-for-adaptive-traffic-management-using-a-wireless-mesh-sensor-networks/}{ttfamily advantech-bb.com}
  Accessed: 15 October 2017.

  bibitem{def5}
  Elsevier. {itshape Data-driven smart-city-enabled traffic system modeling,
  analysis and optimization.}
  href{https://www.journals.elsevier.com/transportation-research-part-c-emerging-technologies/call-for-papers}{ttfamily www.journals.elsevier.com}
  Accessed: 15 October 2017.
end{thebibliography}

end{document}