• Title/Summary/Keyword: minimum requirements

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Minimum Specific Airflow Rate Requirements for Natural Air Drying of Rough Rice in Korea (벼 상온통풍건조의 최소풍량비에 관한 연구)

  • 금동혁;박선태
    • Journal of Biosystems Engineering
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    • v.21 no.1
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    • pp.60-71
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    • 1996
  • The purposes of this study were to develop a simulation model and to determine minimum specific airflow rate requirements for natural air drying of rough rice in Korea. A simulation model was developed considering energy and mass balances within grain bed, drying and rewetting rates, and hysterisis effect between sorption and desorption isotherms. As the results of validation test, the moisture contents predicted by the model agreed very well with the actual data. The criteria for determining minimum specific airflow rate requirements was that the top loom layer in the bin be dried to a moisture content below 16 percent wet basis with less than 0.5% drymatter decomposition. The minimum specific airflow rate requirements in 13 locations of Korea were presented based on the worst one among the past 7 to 13-year weather data. These requirements were also presented for all the combinations of three harvest dates and four harvest moisture contents. Specific airflow rate requirements seemed to be half by each 2 percent reduction in moisture content from 24 percent. As harvest date was delayed by 10 days from October 1, these requirements were reduced by about 20 to 40 percent.

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Safety Requirements and Test Methods of a Radiofrequency Stimulator

  • Park, Sang-Geon
    • Journal of information and communication convergence engineering
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    • v.14 no.3
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    • pp.191-199
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    • 2016
  • In this study, we investigate the safety requirements and test methods of a radiofrequency stimulator. The main test items include controls of a minimum output, accommodation range, and output parameters that have been known as the safety requirements in conformity with international standards. As the test criteria for controlling the minimum output, an increase or decrease in a unit of 1 mA or 1 V or less was applied to the output amplitude regulator for both continuous and discontinuous control, and the output at the minimum setting was manipulated to not exceed 2% of the maximum setting. For controlling the output parameters, one of the representative test criteria states that the current limit of 250 mA should be equal to or less than 1,500 Hz. Consequently, when applying the radiofrequency stimulator on the human body, we need to ensure that the safety requirements conform to the international standards.

Evaluation of Minimum Extensibility Standard Requirements for Steel Reinforcement (철근 최소 연신율 규격에 대한 평가)

  • Lee, Jae-Hoon;Kim, Dong-Hyun;Choi, Jin-Ho
    • Journal of the Korea Concrete Institute
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    • v.23 no.5
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    • pp.559-567
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    • 2011
  • Recently, many researches on high strength reinforcing steel have been conducted to construct optimum reinforced concrete structures. However, the studies have shown that high strength steel shows less elongation capacity than normal strength steel. Therefore, high strength reinforcing steel may not satisfy the minimum elongation requirement of current standards. Moreover, elongation measurements may be not standardized ones since each standard has its own requirements for minimum elongation and gage length. Therefore, the standards for reinforcing steel testing must be investigated to verify the validity of Korean Standard D 3504. This research aimed to compare the requirements for minimum elongation and gage length of the Korean, American, Japanese, European, and ISO Standards. Then, the study further investigated accuracy of the standards by tensile test of reinforcing steel. The study results showed that the Korean Standard has the strictest requirement. Based on the study results, the authors proposed modified minimum elongation requirements for general reinforcing steel and new requirements for seismic reinforcing steel.

A Study on the Architectural Planning for Establishing Minimum Requirements of Ward in Korean General Hospital (우리나라 종합병원 병동부의 최소기준 설정을 위한 건축계획적 연구)

  • Kwon, Oh-Young;Yang, Nae-Won
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.4 no.7
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    • pp.67-74
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    • 1998
  • Although Medical Care System pays medical fee for each patients with the establishment of National Medicare System, patients cannot be equally benefited from hospitals. At present, the Korean government provides minimum requirements on medical facilities in enforcement of medical law, but it is not enough to guarantee the rights of patients. The purpose of this study is in search for the way to improve the minimum requirements of ward which will be needed to examine the present situation of general hospitals, to find out their problems, and to compare the law of medical facilities in korea.

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Minimum Thickness of RC Bridge Slab Considering Fatigue and Serviceability (피로강도와 사용성을 고려한 RC 바닥판의 최소두께)

  • Hwang Hoon Hee;Joh Changbin;Kim Byung Suk;Jung Chul Hun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.05a
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    • pp.248-251
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    • 2004
  • This study was performed to propose the minimum thickness of RC slab that satisfies constructibility, fatigue safety, and serviceability requirements such as deflection control. Three different minimum thicknesses are calculated using concrete shear and rebar fatigue formulas, and deflection control, respectively, and checked by constructiblity. The maximum of these three minimum thicknesses is proposed as the minimum thickness of RC slab, which shows that the minimum thickness requirement of RC slab from Korean Bridge Design Code can be thinner than now.

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The Study on the Minimum Requirements for the Design of an Airpark used in Light Sport Aircraft Operations (경량항공기 이착륙장의 최소 요구조건에 대한 연구)

  • Shin, Dai-Won;Shin, Hong-Chul
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.17 no.2
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    • pp.18-22
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    • 2009
  • In this study, we surveyed the operating status of the Light Sport Aircraft(LSA) in Korea, and reviewed the minimum requirements of the airpark for LSA in other countries. Based on the information, we presented the airpark standards to ensure the safe take-off, landing, and operation of LSA in Korea.

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The Requirements on statistical techniques in QS-9000

  • Yamada, Shu
    • International Journal of Quality Innovation
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    • v.1 no.1
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    • pp.24-31
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    • 2000
  • QS-9000 was established by Chrysler, Ford, General Motors and some Truck Manufactures to solve problems of efforts to prepare original standards for each company. When we compare the requirements in QS-9000 with those in ISO 9000, we may observe that those of QS-9000 are more specific, since the user of the standard is limited to the automobile industry. In particular, the requirements on statistical techniques are described in more detail. In this paper, we present the requirements on statistical techniques in QS-9000. Specifically, we review the contents of QS-9000 and explore the philosophy and the minimum requirement on statistical techniques behind the description.

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A Study on the Safety Requirements Establishment through System Safety Processes (시스템 안전성평가를 통한 효율적 요건 도출방안 연구)

  • Yoo, Seung-woo;Jung, Jinpyong;Yi, Baeck-Jun
    • Journal of Aerospace System Engineering
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    • v.7 no.2
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    • pp.29-34
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    • 2013
  • Safety requirements for aircraft and system functions include minimum performance constraints for both availability and integrity of the function. These safety requirements should be determined by conducting a safety assessment. The depths and contents of aircraft system safety assessment vary depending on factors such as the complexity of the system, how critical the system is to flight safety, what volume of experience is available on the type of system and the novelty and complexity of the technologies being used. Requirements that are defined to prevent failure conditions or to provide safety related functions should be uniquely identified and traceable through the levels of development. This will ensure visibility of the safety requirements at the software and electronic hardware design level. This paper has prepared to study on promoting the efficiency of establishing hierarchical safety requirements from aircraft level function to item level through system safety processes.

Localization Requirements for Safe Road Driving of Autonomous Vehicles

  • Ahn, Sang-Hoon;Won, Jong-Hoon
    • Journal of Positioning, Navigation, and Timing
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    • v.11 no.4
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    • pp.389-395
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    • 2022
  • In order to ensure reliability the high-level automated driving such as Advanced Driver Assistance System (ADAS) and universal robot taxi provided by autonomous driving systems, the operation with high integrity must be generated within the defined Operation Design Domain (ODD). For this, the position and posture accuracy requirements of autonomous driving systems based on the safety driving requirements for autonomous vehicles and domestic road geometry standard are necessarily demanded. This paper presents localization requirements for safe road driving of autonomous ground vehicles based on the requirements of the positioning system installed on autonomous vehicle systems, the domestic road geometry standard and the dimensions of the vehicle to be designed. Based on this, 4 Protection Levels (PLs) such as longitudinal, lateral, vertical PLs, and attitude PL are calculated. The calculated results reveal that the PLs are more strict to urban roads than highways. The defined requirements can be used as a basis for guaranteeing the minimum reliability of the designed autonomous driving system on roads.

Eliminating the Third Harmonic Effect for Six Phase Permanent Magnet Synchronous Generators in One Phase Open Mode

  • Liu, Jian;Yang, Gui-Jie;Li, Yong;Gao, Hong-Wei;Su, Jian-Yong
    • Journal of Power Electronics
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    • v.14 no.1
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    • pp.92-104
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    • 2014
  • To insure stable operation and eliminate twice torque ripple, a topology for a six phase permanent magnet synchronous generator (SP-PMSG) with a neutral point connected together was analyzed in this paper. By adopting an extended transformation matrix, the mathematic model of the space vector control was established. The voltage and torque equations were deduced while considering the third harmonic flux and inductance. In addition, the suppression third harmonic method and the closed loop control strategy were proposed. A comparison analysis indicates that the cooper loss minimum method and the current magnitude minimum method can meet different application requirements. The voltage compensation amount for each of the methods was deduced which also takes into account the third harmonic effect. A simulation and experimental result comparison validates the consistency through theoretical derivation. It can be seen that all of the two control strategies can meet the requirements of post-fault.