South Korean e-commerce operator Coupang is expected to log mounting operating losses for 2015 due to hefty investments in the firm’s logistics capacity, industry sources said Thursday. Coupang is expected to log over 400 billion won ($326.9 million) in operating losses when it files its 2015 audit report in mid-April due to rising costs in building new logistics centers and hiring new staff, according to the sources.Coupang’s sales were estimated to have jumped more than fourfold last year from