Mr. Melvin says he spends hours at the computer tracing power lines, looking for telltale shadows of electric towers or posts.

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Sidney Jones, of the International Crisis Group, says the police are getting much better at tracking down suspects and tracing their accomplices.

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In the process of helping him find his family, we engaged the NGO world at large and discovered that refugee family tracing was predominantly carried out via pen and paper and physical archives not connected to a searchable grid, and with very little technology taken into account.

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As I have often reported, tracing botnets to their masters is difficult at best and can be a Sisyphean task.

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The delivery service, part of the Royal Mail Group, apologised for the failure in the system which allowed people using the mail tracing service access to the name, postcode and signature at various addresses.

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"The Polaroid Years: Instant Photography and Experimentation" at the Frances Lehman Loeb Art Center at Vassar College does a respectable job, within space constraints, of tracing the company's imprint on the post-1970s American art world.

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What if the systems were not involved at all, but someone made a mistake in the complicated forensic analysis that accompanies tracking and tracing?

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On a typical day at home, Ms. Cook said she tries to keep up a routine by asking Jermarl to practice tracing the alphabet or draw and paint.

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