【环球时报综合报道】《环球时报》记者9月14日从中国航天科技集团六院处获悉，由航天科技集团六院西安航天动力研究所自主研究设计的某型液氧煤油发动机实现重复飞行试验验证，该型发动机作为某飞行器主动力装置参加首飞试验后，经检测维护，顺利完成了重复飞行试验，这也是国内首次实现液体火箭动力的重复使用。自由进出太空，是航天运输系统后续发展的主要方向，发展可重复使用航天运载器则是实现自由进出太空的关键环节。近年来，随着美国“猎鹰9号”火箭重复使用的成熟应用，各国已经掀起新一轮重复使用技术的发展热潮。    The cell phones, tablets, and laptops left behind by veterans who died by suicide may offer insight that could help prevent future military suicides, according to a nonprofit dedicated to analyzing the data from the devices.Stop Soldier Suicide collects the technology as part of its initiative, "The Black Box Project," which is named after the black boxes found on planes that help determine the cause of aviation incidents."If we could gather novel data from those that have died by suicide, we might be able to recreate the last year of life," Stop Soldier Suicide CEO Chris Ford told ABC News.Veterans are 57% more at risk for suicide than non-military adults and around 6,000 veterans die by suicide each year, according to the Department of Veterans Affairs."I think we can prevent needless suffering and a ton of loss of life," Ford said.That kind of loss is something David McDaniel, whose son Connor died by suicide at the age of 26, knows all too well.Connor McDaniel joined the Army after high school, and, according to David, he appeared upbeat during his deployment to Afghanistan, where he was assigned to protect local villages from the Taliban."Some of his Army buddies told me that he was making them laugh while they were being shelled in Afghanistan," David McDaniel told ABC News.But it wasn't long after Connor came home that David McDaniel says he sensed a shift in his son's behavior to include "more anger, a lot of frustration, a lot of gloominess."On Sept. 1, 2021, David says his son entered a wooded area with a firearm."I start screaming his name as I'm walking up the field. And just then the police, the sheriff's department shows up and they tell me to come back down," McDaniel said.He followed their direction, but on the car ride home, an officer called him and said Connor was dead after he fired upon sheriff's deputies and the deputies returned fire and killed him.Connor's death was determined to be a suicide. The district attorney's office concluded that the officers' actions were justified.While grappling with his son's death, David McDaniel was immediately drawn to the Black Box Project, which uses forensic software to unlock and comb through service members' devices provided by their loved ones to review their activity in the weeks leading up to their suicides.McDaniel works in the tech field and says if the project can find repeated patterns in online searches, they may be able to help others to prevent suicides.For instance, McDaniel says his son searched for SGLI, Servicemembers' Group Life Insurance, before his death. If a veteran were to make a similar search and look up "suicide" in the future, for example, McDaniel suggests it could trigger an ad for Stop Soldier Suicide to pop up and provide resources in the search results.Ford says the nonprofit uses machine learning, a subfield of artificial intelligence, to analyze texts and notes in order to determine sentiment or emotional tone, such as anger or desperation. He says they can also track phone usage of the deceased veterans to monitor their past sleep cycles and trace their past geo-locations."Machines can go through computations a lot faster than humans, and they can find signals that we often miss," Ford said.Since launching the Black Box Project in April 2020, Stop Soldier Suicide has received over 100 devices, Ford said. So far, he says they're seeing three patterns before most of these suicides: more anger, different sleep patterns, and social isolation.Ford's team includes Ph.D.s in clinical psychology and suicide researchers. A scientific advisory committee helps steer where and what to look for on the devices.The findings are still preliminary, according to the nonprofit, but one goal is to help the organization decide where, when, and how to target their own mental health resources, like adding more hotline staff at certain hours and ensuring calls are picked up overnight.When asked about privacy concerns of collecting data, Ford said it's something they think about daily."We don't resell the data. We don't push it out to others. We use it for our own research purposes so that we can best understand risk and then give those devices back to those families intact," Ford said.Current privacy laws do not carry on past death, meaning the next of kin typically gains new authority.Petra Oxford-Jackson, whose veteran husband Anthony died by suicide, says she gave his phone to the organization with the possibility it could save even one life."I truly believe he would have been okay with it, and it's a hard thing for a survivor to give up something so personal as his cell phone," Oxford-Jackson told ABC News.The Black Box Project received $3 million in funding from the Department of Veterans Affairs earlier this year.If you are struggling with thoughts of suicide or worried about a friend or loved one, call or text the Suicide & Crisis Lifeline at 988 for free, confidential emotional support 24 hours a day, seven days a week.。而液体火箭发动机作为航天运载器的主要动力装置，具有功能全、性能高、任务适应强、技术难度大、研制周期长等特点，也是航天运载器最复杂的产品之一，其可重复使用成为实现航天运载器重复使用必须突破的关键技术之一。

B | 据介绍，该型液氧煤油发动机作为我国新一代运载火箭的主要动力装置，具有高性能、大推力、无毒无污染等优点。该发动机从设计之初，部组件方案及总体布局按多次工作的要求开展论证，地面研制试验实现了单台发动机不下台重复试车8次。然而，可重复地面试车并不代表着发动机可以适应可重复使用。液体火箭发动机可重复使用还需要突破多次起动、低入口压力快速起动、大范围推力调节、状态评估检测及健康管理、快速简化处理、高温组件结构抗疲劳寿命评估及延寿、全任务剖面复杂力热环境预示及控制等关键技术。据了解，该型发动机于2021年作为某飞行器主动力装置参加首飞试验，经检测维护后参加本次重复飞行试验任务。据公开报道，2021年7月16日，由航天科技集团一院研制的亚轨道重复使用演示验证项目运载器在酒泉卫星发射中心点火起飞，按照设定程序完成飞行后，平稳水平着陆于阿拉善右旗机场。今年的8月26日，该升力式亚轨道运载器的重复使用飞行试验获得圆满成功。飞行试验采用的运载器经健康检测维护后，在酒泉卫星发射中心再次点火垂直起飞，按照设定程序完成亚轨道飞行，平稳水平着陆于阿拉善右旗机场，成功实现我国亚轨道运载器的首次重复使用飞行。据介绍，此次完成重复飞行试验的液氧煤油发动机从一次飞行使用到两次飞行使用这一小步的意义非凡，它为后续我国开展更大推力的可重复使用液氧煤油发动机研制积累了宝贵经验、探索了道路，标志着中国航天液体动力可重复使用实现了从零到有的突破，迈出了坚实的一大步。（樊巍 党锋刚 王飞）