Life Support Goals Including High Closure and Low Mass Should Be Reconsidered Using Systems Analysis

نویسنده

  • Harry W. Jones
چکیده

Recycling space life support systems have been built and tested since the 1960’s and have operated on the International Space Station (ISS) since the mid 2000’s. The development of space life support has been guided by a general consensus focused on two important related goals, increasing system closure and reducing launch mass. High closure is achieved by recycling crew waste products such as carbon dioxide and condensed humidity. Recycling directly reduces the mass of oxygen and water for the crew that must be launched from Earth. The launch mass of life support can be further reduced by developing recycling systems with lower hardware mass and reduced power. The life support consensus has also favored using biological systems. The goal of increasing closure using biological systems suggests that food should be grown in space and that biological processors be used for air, water, and waste recycling. The goal of reducing launch mass led to use of Equivalent System Mass (ESM) in life support advocacy and technology selection. The recent consensus assumes that the recycling systems architecture developed in the 1960’s and implemented on ISS will be used on all future long missions. NASA and other project organizations use the standard systems engineering process to guide hardware development. The systems process was used to develop ISS life support, but it has been less emphasized in planning future systems for the moon and Mars. Since such missions are far in the future, there has been less immediate need for systems engineering analysis to consider trade-offs, reliability, and Life Cycle Cost (LCC). Preliminary systems analysis suggests that the life support consensus concepts should be revised to reflect systems engineering requirements.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Comparison of Pregnancy Self-Care, Perceived Social Support and Perceived Stress in Low-risk and High-risk Groups

Background & objectives: Although, pregnancy and delivery are natural processes in woman's life, they are stressful experiences with emotional, physical and social changes. Woman’s response to pregnancy is affected by a variety of factors, among which pregnancy age can be considered as the most important factor with significant effects on pregnancy and delivery processes. This study was conduct...

متن کامل

Optimal Reconfiguration of Distribution Network for Power Loss Reduction and Reliability Improvement Using Bat Algorithm

In power systems, reconfiguration is one of the simplest and most low-cost methods to reach many goals such as self-healing, reliability improvement, and power loss reduction, without including any additional components. Regarding the expansion of distribution networks, communications become more complicate and the number of parameters increases, which makes the reconfiguration problem infeasib...

متن کامل

Monitoring Sustainable Development Goals 3: Assessing the Readiness of Low- and Middle-Income Countries

Background The Millennium Development Goals (MDGs) availed opportunities for scaling up service coverage but called for stringent monitoring and evaluation (M&E;) focusing mainly on MDG related programs. The Sustainable Development Goals 3 (SDGs) and the universal health coverage (UHC) agenda present a broader scope and require more ...

متن کامل

Cold work simulation of hole expansion process and its effect on crack closure

Using cold working fastener holes is a simple life enhancement procedure that strengthens metallic components by retarding crack growth around a hole. In the present paper, the residual stress field that is induced by the hole expansion process is obtained based on different material models namely elastic perfect plastic, isotropic hardening and kinematic hardening using three-dimensional finit...

متن کامل

Mass Participation Factor in Defining Non-classical Range of Behavior for Mass Isolated Systems

The new techniques in seismic design of structures are usually attributed to high damping ratios. In such systems, the assumption of classical (i.e. proportional) damping is not valid and in most cases they should be considered as Non-classical systems. Since the analytical tools for studying the behavior of such structures are not easily available, the present work attempts to find the limits,...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2017