• Title/Summary/Keyword: Simulant

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Experimental Studies on Risks of BB Pellets Using Gelatine Based Simulants (젤라틴 Simulant를 이용한 비비탄총 탄환의 위험성에 관한 실험적 연구)

  • Park, Dal-Jae;Kim, Hyung-Suk;Lee, Young-Soon
    • Journal of the Korean Society of Safety
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    • v.26 no.3
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    • pp.29-33
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    • 2011
  • Experimental studies were performed to investigate the injury potential of BB pellets through gelatine based simulants. In order to record BB pellet movements penetrating into the target simulant, a high-speed video camera was used. In this study the first investigation involved the effects on concentrations, homogeneity and gelation times of the gelatine simulant. The second investigation involved the penetration depth of the pellets to the simulant by different distances between the BB gun and the simulant. The final one is associated with impact velocity, threshold velocity and penetration depth of the pellets by different kinetic energies of the BB gun. Results provided the basis in assessing the injury potential of BB pellets.

Simulant Gel Propellant Characteristics depending on Mixing Method (제작방법에 따른 모사 젤 추진제의 특성 연구)

  • Kim, Jae-Woo;Jun, Doo-Sung;Shin, Woong-Sup;Lee, Hyo-Mi;Moon, Hee-Jang
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.11a
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    • pp.467-470
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    • 2011
  • In this study, two different kind of impeller, commercial hand blender and manual type were used to investigate the most effective mixing method for simulant gel propellant. Ionized Water, Carbopol 941 and NaOH were used to produce the simulant gel for temperature of $25^{\circ}C$ and $50^{\circ}C$. The amount of bubbles produced during mixing of simulant gel at $50^{\circ}C$ were higher than that of simulant gel at $25^{\circ}C$. After 24 hours, bubbles of simulant gel made at $50^{\circ}C$ disappeared rapidly with respect to the bubbles of gel made at $25^{\circ}C$. Bubbles from blender did show notable amount even after 24 hours. Among mixing type, it was found that the pitched paddle impeller was the best candidate for the production of simulant gel.

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Development of a New Lunar Regolith Simulant using an Automated Program Framework

  • GyeongRok Kwon;Kyeong Ja Kim;Eungseok Yi
    • Journal of Astronomy and Space Sciences
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    • v.41 no.2
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    • pp.79-85
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    • 2024
  • Nowadays, the trend in lunar exploration missions is shifting from prospecting lunar surface to utilizing in-situ resources and establishing sustainable bridgehead. In the past, experiments were mainly focused on rover maneuvers and equipment operations. But the current shift in trend requires more complex experiments that includes preparations for resource extraction, space construction and even space agriculture. To achieve that, the experiment requires a sophisticated simulation of the lunar environment, but we are not yet prepared for this. Particularly, in the case of lunar regolith simulants, precise physical and chemical composition with a rapid development speed rate that allows different terrains to be simulated is required. However, existing lunar regolith simulants, designed for 20th-century exploration paradigms, are not sufficient to meet the requirements of modern space exploration. In order to prepare for the latest trends in space exploration, it is necessary to innovate the methodology for producing simulants. In this study, the basic framework for lunar regolith simulant development was established to realize this goal. The framework not only has a sample database and a database of potential simulation target compositions, but also has a built-in function to automatically calculate the optimal material mixing ratio through the particle swarm optimization algorithm to reproduce the target simulation, enabling fast and accurate simulant development. Using this framework, we anticipate a more agile response to the evolving needs toward simulants for space exploration.

Basic Study for a Korean Lunar Simulant (KLS-1) Development (한국형 인공월면토(KLS-1) 개발을 위한 기초 연구)

  • Ryu, Byung-Hyun;Baek, Yong;Kim, Young-Seok;Chang, Ilhan
    • Journal of the Korean Geotechnical Society
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    • v.31 no.7
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    • pp.53-63
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    • 2015
  • For the success of future missions to the Moon and other similar cosmic environments, understanding and utilization of the lunar regolith has become essential. However, due to the scarcity and unaffordability of real lunar regolith on Earth, a number of lunar regolith simulants (e.g., JSC-1; NASA) have been developed for experimental purposes. However, Korea does not have its own lunar regolith, even though the country is planning to actively pursue lunar and space missions in the 2020s. Thus, this study has been conducted to develop a Korean lunar simulant prototype via basic feasibility attempts (e.g., raw material selection, particle size and chemical composition simulation). Finally, the first prototype of Korea's own lunar simulant has been obtained, and denominated as KLS-1.

Development of Korean Lunar Highland Soil Simulant (KIGAM-L1) (한국형 달 고원 모사토(KIGAM-L1) 개발)

  • Tae-Yun Kang;Eojin Kim;Kyeong Ja Kim
    • Journal of Space Technology and Applications
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    • v.4 no.2
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    • pp.121-136
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    • 2024
  • Korea Pathfinder Lunar Orbiter (KPLO), launched in August 2022, is successfully carrying out its mission. Korea's lunar lander and rover programs are expected to proceed in the future. To successfully carry out the mission after the lunar lander has landed on the surface, the performance of the equipment to be mounted should be checked in a laboratory environment similar to the Moon. Scientists and engineers of several countries, including the United States and China, use lunar soil simulant which is developed to resemble lunar soil for simulating the surface of the lunar landing site. Several lunar probe landing sites are being discussed in Korea, and lunar soil simulants such as Korea Hanyang Lunar Simulant-1 (KOHLS-1), Korea Aerospace University Mechanical Lunar Simulants (KAUMLS), and Korea Lunar Simulant-1 (KLS-1), which are similar to the characteristics of lunar mare soil, have been developed. However, those simulants are not useful if the landing site is chosen as a highland area. In this study, we introduce the process of developing KIGAM-L1, a lunar highland soil simulant similar to the chemical composition of the Apollo 16 lunar soil sample and the particle size distribution of lunar soil sample 60500-1, in case the lunar lander lands at highland area.

A Numerical Design and Feasibility Study of Self-Wastage Experiment Using Simulant Material in a Sodium Fast Reactor

  • Jang, Sunghyon;Takata, Takashi;Yamaguchi, Akira
    • Nuclear Engineering and Technology
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    • v.48 no.2
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    • pp.368-375
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    • 2016
  • A sodiume-water reaction takes place when high-pressured water vapor leaks into sodium through a tiny defect on the surface of the heat transfer tube in a steam generator of the sodium-cooled fast reactor. The sodiume-water reaction brings deterioration of the mechanical strength of the heat transfer tube at the initial leakage site. As a result, it damages the crack itself, which may eventually enlarge into a larger opening. This self-enlargement is called "self-wastage phenomenon." In this study, a simulant experiment was proposed to reproduce the self-enlargement of a crack and to evaluate the mechanism of the self-wastage. The damage on the surface of the crack was simulated by making the neutralization reaction with hydrochloric acid solution and sodium hydroxide solution. A numerical investigation was carried out to validate the feasibility of the approach and to determine experimental conditions. From the computation results, it is observed that when 5M HCl is injected into 5M of NaOH with 0.05 m/s inlet velocity, the temperature at the surface near the crack increased over 319.26 K. The computational results show that the self-wastage phenomenon is capable of being reproduced by the simulant experiment.

Surface Tension Change of Simulant Gel Propellant according to the Metal Particle Addition (금속입자 첨가에 따른 모사젤 추진제의 표면장력 변화)

  • Kim, Kyehwan;Kim, Sijin;Han, Seungjoo;Kim, Jinkon;Moon, Heejang
    • Journal of the Korean Society of Propulsion Engineers
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    • v.21 no.3
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    • pp.34-40
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    • 2017
  • In this study, the surface tension of simulant gel propellants was measured by Du $No{\ddot{u}}y$ ring method. The variation of the surface tension was investigated with respect to the amount of the gelling agent, and metal particle addition. Distilled water was used as the base fluid for the preparation of the simulant gel propellant where Carbopol 941 was used as a gelling agent and SUS304 spherical metal particles (mean diameter : 100 nm) as simulant energetic particles. As a result of measurements, surface tension increased with increasing gelling agent concentration while, in the presence of metal particle, different behavior of surface tension has been observed.

Comparison of the Overall Migration Values from Various Plastic Food Packaging Materials into Food Simulants Under High Temperature Testing Conditions as Described in the Regulations of Different Country areas (각 국가 권역별 이행 실험방법에 따른 고온가열 식품포장재의 시뮬란트별 총이행량 비교)

  • 이근택;김동주
    • Journal of Food Hygiene and Safety
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    • v.16 no.4
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    • pp.333-341
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    • 2001
  • The actual overall migration data obtained from plastic food packaging materials into food simulants under high temperature testing conditions as described in the regulations of European Union, USA, and Korea or Japan were compared. Overall migration values(OMVs) with non-fatty food simulants under high temperature conditions were observed to be generally below 2.5 mg/dm$^2$ except polyamides(CPA and PA 6,6) which were tested at 121$^{\circ}C$ for 2 hrs. As for the fatty food simulants, the OMVs with soybean oil were higher than other simulants. Among the films tested, PVC wrap showed higher OMVs ranging between 23.9 and 54.6 mg/dm$^2$than others. The OMVs were measured at higher level with the elevation of contact temperature and the extension of contact time, and in fatty food simulants rather than in non-fatty simulants. Under similar testing temperature and time conditions. the OMVs tended to be increased in polar films like PA with polar simulants, and contrarily in non-polar films like PO with non-polar simulants. It is noteworthy that a discrepancy with regard to the result of OMVs was observed for some films as a result of different migration testing methods and conditions of each country areas.

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Formulation of the Sucrose-Free Simulant Human Tissue for SAR Measurement at CDMA Mobile Band

  • Gimm, Yoon-Myoung
    • Journal of electromagnetic engineering and science
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    • v.7 no.2
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    • pp.53-58
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    • 2007
  • A general method to formulate the tissue-equivalent liquids for SAR measurement is proposed to make sucrose-free brain tissue applicable at 835 MHz as an example We suggest the tissue composition can be determined by measuring the dielectric constants and conductivities with the DI water and salt addition variation to the pre-manufactured auxiliary liquid of DGBE and TritonX-100 The manufactured liquid satisfies the specified electrical parameters of international standard at 835 MHz.

A Study on Lunar Soil Simulant Pretreatment for Effective Simulation of Lunar Surface Environment (달 지상 환경의 효과적 모사를 위한 인공월면토 전처리에 관한 연구)

  • Chung, Taeil;Kim, Young-Jae;Ryu, Byung-Hyun;Shin, Hyu-Soung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.40 no.1
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    • pp.51-58
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    • 2020
  • As interest in lunar exploration increases, studies on lunar surface environment simulation including a lunar soil simulant are being conducted. One of the problems when creating a vacuum environment with lunar soil is that it takes long time to reach high vacuum due to outgas from the soil. Most of the outgas is water, and the time to reach high vacuum can be significantly reduced by a pretreatment process that removes moisture adhering to the surface of the lunar soil before putting soil into a vacuum chamber. The existing soil drying methods were examined to determine how these methods were effective to remove moisture from the lunar simulant soil. Drying experiments of lunar soil samples were carried out using a dry oven, a microwave oven, direct heating method and a vacuum oven, and the results of the drying experiment were presented. Drying soil at 110℃ using a dry oven and drying soil by a microwave oven were not enough to remove moisture, and vacuum oven drying method and direct heating drying method at more than 200℃ were effective in water removal.