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由于资本投资的不足 ,大幅度地提高轮轨寿命的技术革命绕过了发展中国家 ,但是这些国家也可采用一些廉价而有效的技术
Because of the lack of capital investment, technological revolutions that greatly increase the life-cycle of the wheel-rail bypass the developing countries, but these countries may also adopt some cheap and effective technologies