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In the Closed Ecology Experiment Facilities (CEEF), with integrating the Closed Plantation Experiment Facilities (CPEF) and the Closed Animal Breading & Habitation Facilities (CABHF), closed habitation experiments without material exchange with the outside will be conducted after the 2005 fiscal year. Cultivation experiments of about 30 crops and the integrating test of the material circulation system required for the closed habitation experiments have been performed since 2000 fiscal year. Using data reported in these experiments, material circulation in CEEF is simulated based on the recent operation strategy, and the storage capacity needed for the buffer of an air processing subsystem was estimated. In order for two humans to dwell over 120 days, the storage capacities of the carbon dioxide tank, the oxygen tank, and the waste gas tank in CPEF, and the carbon dioxide tank and the oxygen tank in CABHF are 820 g, 2830 g, 4425 g, 1780 g, and 1792 g, respectively.

A habitation experiment using the Closed Ecology Experiment Facilities was started in 2005. In the future, the stays will be gradually extended. We have been developing the three layered control software for a Control Computer System of the Closed Ecology Experiment Facilities in order to back up the habitation experiments. In this paper, we will show the development of an operation scheduling system for one of the three layers, such as at the planning and scheduling level, and discuss the development of a scheduling algorithm that does not cause the complexity of the ALS scheduler to be exponentially increased.

We developed an Advanced Life Support systems scheduler (ALS scheduler) to back up the habitation experiments of Closed Ecology Experiment Facilities (CEEF), and integrated the Lagrangian decomposition and coordination method for a scheduling algorithm of the scheduler. Later research revealed that when comparing solutions obtained by the Lagrangian decomposition and coordination method and by a skilled operator, respectively, a schedule sought by the skilled operator has different features from those of a schedule sought by the Lagrangian decomposition and coordination method. This paper describes how to generate a schedule such as one created by a skilled operator, while reducing complexity by integrating empirical knowledge to the Lagrangian decomposition and coordination method.

The Nitrogen Fixation System (NFS) which produces ammonia and nitric acid from nitrogen and water has been developed. The NFS is one essential part of material circulation system of the CEEF (Closed Ecological Experiment Facility) the first Japanese CELSS experiment facility. Basically, physico-chemical and some new technologies are utilized as elemental processes in the NFS. Low pressure ammonia synthesis, ammonia enrichment with PSA and water electrolysis with SPE are such new technologies. We designed and installed the NFS as a subsystem of CEEF. The capacity of the NFS is 125g/day as fixed nitrogen. First operation of NFS is expected to be done early fiscal year of 1996 in CEEF.

The basal metabolism of the Candidate Animal is mainly on energy metabolism that was estimated for future animal breeding in CEEF as preliminary research. The amounts of gas exchange in the respiration and heat production of the Shiba goat (native Japanese goat) were analyzed to predict energy and material flow of the animal breeding system in the Closed Ecology Experiment Facilities (CEEF). Experimental animals were fed Timothy hay or inedible parts of rice cultivated in CEEF. The feces and urine were collected during the 7-day metabolism measurement period after a 2-week preliminary breeding period. The O2 consumption, CO2 production, and CH4 production were measured by a mass spectrometric respiration gas analysis system on the 7th day of the metabolism measurement period. Heat production was also obtained from these data. O2 consumption, CO2 production and CH4 production were 100.3 - 153.8 L, 127.2 - 174.0 L and 5.7 - 10.8 L per day (at 0°C, 0.101MPa), respectively.

Before a series of overall material circulation in an experimental system including crops, animals and humans, technical examinations for the development of a waste processing system were conducted for incorporating the system to the Closed Ecology Experiment Facilities (CEEF). The examinations are intended to validate the function of the carbonization and incineration processing units which were installed in the CEEF in 2006. Using different mock-up samples, examinations have been carried out to verify the function and capability of the whole system, including the waste carbonization processing unit, incineration processing unit, exhaust gas tank and the exhaust gas processing unit. In an examination using filter paper pulp as a mock-up sample, processing time in each unit was checked. The processing times needed for carbonization and incineration processing were 5.7 and 2.6 hours, respectively.

The simulation test for the controlled ecological life support system is planned by Institute for Environmental Sciences (IES) of Japan. The purpose of this test is to confirm that in the closed space, the environmental and life support system is normally carried out. The establishments to perform the simulation test has been constructed at Rokkasho-mura village, Aomori prefecture, in Japan. We have been developed “Oxygen Recovery System” which decompose carbon dioxide (CO2) and regenerate oxygen(O2), for the simulation test. The oxygen recovery system consists of a equipment to reduce CO2 using the Sabatier method and a equipment to regenerate oxygen using water electrolysis method (Refer to Figure 1). And this reaction principle is as follows; The carbon dioxide is produced by the respiration of human, animals and plants. The carbon dioxide is reduced to methane and water using hydrogen in the first reaction.

In the closed environments such as manned space station, it is necessary to remove contaminant gas to keep a suitable environment. Removal of gaseous contaminants generated from crew, animals, and plants is important function to keep the environment below the allowable level in the Closed Ecology Experiment Facilities (abbreviated as CEEF). CEEF consist of three modules for habitat, animal and plant, the supporting facilities for each module and a plant cultivation facility. CEEF are scheduled to be constructed from 1994 in Aomori Prefecture, northern part of Japan. For designing Trace Contaminant Control Assembly (TCCA) for CEEF, the following six (6) trace contaminants have been selected as major contaminant gas in CEEF; Ammonia (NH3) Methane (CH4) Ethylene (C2H4) Carbon Monoxide (CO) Nitrogen Dioxide (NO2) Sulfur Dioxide (SO2) Ethylene is well-known as an aggressive contaminant to plant growth and maturity.

The Closed Ecology Experiment Facilities (CEEF) have been under construction in northern Japan since 1994. These facilities contain the Closed Plant Experiment Facility (CPEF), as well as other facilities, in all of which, Controlled Ecological Life Support Systems (CELSS) research and development can be conducted. The CPEF includes two Plant Cultivation Modules (PCMs), which contain a PCM consists of three 30m2 closed cultivation rooms illuminated solely by lamps and a 165.1m3 preparation room, and a PCM consists of a 60m2 closed cultivation room illuminated by natural light and supplemental lamps and a 88.8m3 preparation room, and a Material Circulation System (MCS). Measured rate of air exchange between a 30m2 cultivation room and the preparation room was 0.48% hour-1, and that for a 60m2 cultivation room was about 0.11% hour-1. Air leak rate of the PCM as a whole was less than 0.01% hour-1 under isothermal and equal pressure condition.