International Society of Soil Science国际土壤协会 Initial Sector Suite Subsystem起始扇区管制席位分系统 Interactive Subscriber Service Subsystem交互式服务子系统 Information Systems Security Standards信息系统的安全标准 International Soil Science Society (Italy)国际土壤科学学会(意大利) International Society for Seed Science (Vermillion, South Dakota)国际社会科学的种子,南达科他州朱砂() International Symposium on Skill Science科学技术研讨会 Installation Service Supply Support安装服务提供支持 Instituto da Solidariedade e Segurança Social (Portugal)Instituto da Solidariedade e Segurança Social (Portugal) Interim Strategic Storage Site临时战略储存网站 Internet Self Service and Security (Sprint)网路自我服务和保障(冲刺) Information Society Standardization System信息社会规范体系 International Student and Scholar Services国际的学生和学者的服务 Initial Sector Suite System最初的部门套房系统 Inherent Secondary Shutdown System关闭系统固有的次要