Designing invisibility cloaks that can conceal objects from visible light has been more challenging due to the strict material requirements.

由于十分苛刻的材料要求，设计可见光波段的隐身斗篷更具挑战性。

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Ensures all material requirements are sufficient for production schedules.

确保所有供应的物料能够满足生产计划的需求。

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Special material requirements, and also requires the production of high precision.

其材料要求特殊，且制作精度也要求较高。

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For high value manufacturing, product variety is the single biggest driver of cost as it dictates the material requirements and inventory, which is typically over 80 percent of the total cost.

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In addition, the Securities and Exchange Commission must expand its disclosure requirements to include material non-financial concerns of the type described above.

CENTERFORSECURITYPOLICY: Center For Security Policy

Speculators plug the gap when the hedging requirements of raw-material producers and buyers do not coincide, offering a counterparty for trades that might otherwise have no takers.

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