在目标-攻击弹-防御弹群(target-attacker-defenders,TADs)系统中,防御弹群通过与目标(载机)异构协同、弹群间同构协同以保护载机并降低单弹脱靶的风险。针对TADs系统在二维平面下的协同主动防御模型进行了研究,采用机/弹协同和防御弹...在目标-攻击弹-防御弹群(target-attacker-defenders,TADs)系统中,防御弹群通过与目标(载机)异构协同、弹群间同构协同以保护载机并降低单弹脱靶的风险。针对TADs系统在二维平面下的协同主动防御模型进行了研究,采用机/弹协同和防御弹群协同的两层制导策略。在机弹协同方面,防御弹领弹与载机进行异构协同,考虑载机及防御弹领弹的机动能力限制,采用协同视线制导律(cooperative line of sight guidance,CLOSG)分别得到载机和防御弹领弹的制导指令;在防御弹群协同方面,考虑单弹计算能力约束,拦截时间约束和加速度约束,设计出基于分布式模型预测控制(distributed model predictive control,DMPC)的算法实现弹群从弹和防御弹领弹协同同时抵达并拦截攻击弹。仿真结果表明,多防御弹协同一致拦截制导算法能够实现TADs系统中载机和防御弹群的异构协同主动防御,并实现防御弹群的一致性同时拦截,以降低单弹脱靶的风险。展开更多
A single mammalian transcript normally encodes one protein, but the transcript of GNAS (G-protein u-subunit) contains two reading frames and produces two structurally unrelated proteins, XLas and ALEX. No other conf...A single mammalian transcript normally encodes one protein, but the transcript of GNAS (G-protein u-subunit) contains two reading frames and produces two structurally unrelated proteins, XLas and ALEX. No other confirmed GNAS-Iike dual-coding transcripts have been reported to date, even though many such candidate genes have been predicted by bioinformatics analysis. In this study, we constructed a series of vectors to test how two protein products were translated from a single transcript in vitro. The length of the ORF (open reading frame), position of the first AUG and the Kozak motif were found to be important factors. These factors, as well as 55-bp NMD (nonsense-mediated mRNA decay) rule, were used in a bioinformatics search for candidate dual-coding transcripts. A total of 1307, 750 and 474 two-ORF-containing transcripts were found in human, mouse and rat, respectively, of which 170, 89 and 70, respectively, were found to be potential dual-coding transcripts. Most transcripts showed low conservation among species. Interestingly, dual-coding transcripts were significantly enriched for transcripts from the zinc-finger protein family, which are usually DNA-binding proteins involved in regulation of the transcription process.展开更多
The UN Security Council is faced with a tricky North Korea’s ongoing nuclear and ballistic missile programs,and the consequent decision by South Korea to deploy the Terminal High Altitude Area Defense(THAAD)system,ha...The UN Security Council is faced with a tricky North Korea’s ongoing nuclear and ballistic missile programs,and the consequent decision by South Korea to deploy the Terminal High Altitude Area Defense(THAAD)system,have constituted asignifcant challenge to peace and stability in Northeast Asia.展开更多
文摘在目标-攻击弹-防御弹群(target-attacker-defenders,TADs)系统中,防御弹群通过与目标(载机)异构协同、弹群间同构协同以保护载机并降低单弹脱靶的风险。针对TADs系统在二维平面下的协同主动防御模型进行了研究,采用机/弹协同和防御弹群协同的两层制导策略。在机弹协同方面,防御弹领弹与载机进行异构协同,考虑载机及防御弹领弹的机动能力限制,采用协同视线制导律(cooperative line of sight guidance,CLOSG)分别得到载机和防御弹领弹的制导指令;在防御弹群协同方面,考虑单弹计算能力约束,拦截时间约束和加速度约束,设计出基于分布式模型预测控制(distributed model predictive control,DMPC)的算法实现弹群从弹和防御弹领弹协同同时抵达并拦截攻击弹。仿真结果表明,多防御弹协同一致拦截制导算法能够实现TADs系统中载机和防御弹群的异构协同主动防御,并实现防御弹群的一致性同时拦截,以降低单弹脱靶的风险。
文摘A single mammalian transcript normally encodes one protein, but the transcript of GNAS (G-protein u-subunit) contains two reading frames and produces two structurally unrelated proteins, XLas and ALEX. No other confirmed GNAS-Iike dual-coding transcripts have been reported to date, even though many such candidate genes have been predicted by bioinformatics analysis. In this study, we constructed a series of vectors to test how two protein products were translated from a single transcript in vitro. The length of the ORF (open reading frame), position of the first AUG and the Kozak motif were found to be important factors. These factors, as well as 55-bp NMD (nonsense-mediated mRNA decay) rule, were used in a bioinformatics search for candidate dual-coding transcripts. A total of 1307, 750 and 474 two-ORF-containing transcripts were found in human, mouse and rat, respectively, of which 170, 89 and 70, respectively, were found to be potential dual-coding transcripts. Most transcripts showed low conservation among species. Interestingly, dual-coding transcripts were significantly enriched for transcripts from the zinc-finger protein family, which are usually DNA-binding proteins involved in regulation of the transcription process.
文摘The UN Security Council is faced with a tricky North Korea’s ongoing nuclear and ballistic missile programs,and the consequent decision by South Korea to deploy the Terminal High Altitude Area Defense(THAAD)system,have constituted asignifcant challenge to peace and stability in Northeast Asia.