• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.69-72
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• 2011

The ground tests of the dual pulse solid rocket motors(SRM) were performed to prove the performance of the developed dual pulse solid rocket motors. To achieve dual pulse, pulse seperation device(PSD) and independent ignition systems were installed between the 1st pulse motor and the 2nd pulse motor. The three major development goals are as follow. First, the total impulse of the dual pulse SRM must be over 90% of the single SRM which has same envelopment and weight. Second, the ignition of the 2nd pulse motor can be started at any time between 0 and 60 seconds after termination of the 1st pulse motor. Last, the rupture disk of PSD must not be broken at the 1st pulse pressure, but be broken at below 30% of the 2nd pulse operating pressure. The results of the ground tests satisfied the development goals.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.3
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• pp.342-348
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• 2018

The important issue of equipment installed in maritime weapon system is shock survivability against underwater explosion(UNDEX). If the shock survivability of equipment should not be guaranteed, the successful mission also could not be achieved. For that reason, the shock-resistance of each equipment under UNDEX environment should be demonstrated before deployment at combat field. However, the actual UNDEX test on the ocean is too expensive to conduct. Also, it has diverse dangerous factors. The main characteristic of UNDEX is a dual-pulse shock. The vertical shock test machine able to simulate dual pulse shock signal on the ground will be introduced in this paper. The dual-pulse shock signal presented in certain shock standard was achieved with this shock-test machine on the ground. The analytical procedure to set a test condition was verified by comparing simulation result with experiment result.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.4
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• pp.1276-1291
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• 2014

In the field of visible light communication (VLC), light-emitting diodes (LEDs) are used for transmitting data via visible light. In this study, we analyze pulse dual slope modulation (PDSM) as a means of delivering information in VLC. PDSM involves the modulation of symmetrical slope pulses to encode binary 0s and 1s, and owing to the moderately increasing and decreasing pulse shapes that are created, this method enables more spectral efficiency than the variable pulse position modulation (VPPM) technique currently adopted in IEEE 802.15.7. In particular, PDSM allows for the avoidance of intra-frame flicker by providing idle pulses in a spectrum-efficient way. A simple detection scheme is proposed for PDSMsignals, and its bit error rate (BER) is analyzed mathematically at varying slopes to validate the process through simulation. The BER performance of PDSM detection using dual sampling is compared to the performances of PDSM and VPPM using correlation detection. It is found that, when the probability of idle pulse transmission is less than 0.08 and higher than 0, the BER of dual sampling PDSM is lower than that of PDSM using correlation detection over the entire light intensity range.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.6
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• pp.82-87
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• 2014

Dual pulse rocket motor has a rocket motor with different pulse grains divided by a pulse separation device such as a fragile bulkhead or a thermal barrier type. It distributes thrust energy very effectively via pulse separation device to improve range and terminal velocity of a missile. This paper contains the thermal barrier design and experimental analysis through ground firing tests of small dual pulse motors. The results will be applied to the design, test and evaluation of the scale up dual pulse rocket motor.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.405-408
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• 1998

In this paper, a predictive current control of 12-pulse parallel connected dual converter system with interphase transfromer(IPT) is presented. Firstly, 12-pulse parallel connected dual converter system and the predictive current control of this system is discussed. And the validity of the presented system and the excellence of the predictive current control response is proved through the simyulation and experiment result.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.3
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• pp.331-341
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• 2018

This study proposes an integrated serial spring-damper mechanism as a dual pulse generation system. Compared to the traditional dual pulse generation system, which used multiple springs and a damper to generate a dual pulse critical for impact testing of naval equipments, currently used separated serial spring-damper mechanism is comprised of two components: an air spring, and a damper. The proposed mechanism combines the two components into one integrated system with a unique design that lets simply changing the volume and the pressure of the air tank, and the length of the annular pipe adjust the stiffness and damping constants for testing, eliminating the need to have multiple sets of air springs and dampers. Simulations using MatLab and Simulink were conducted to verify the feasibility of this design. The results show the potential of an integrated serial spring-damper mechanism as a more convenient and flexible mechanism for dual pulse generation system.

• Journal of Power Electronics
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• v.17 no.6
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• pp.1413-1421
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• 2017

In order to control the output voltage in a dual active bridge converter, this paper establishes a theoretical inductor current equation for a dual-pulse-width-modulation scheme that ensures low switching loss. It also proposes a modulation strategy that minimizes conduction loss. When compared to the conventional single-pulse-width-modulation strategy, the proposed approach can reduce the inductor current RMS and improve efficiency in the low power region, as verified through simulation and experimental results.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.666-669
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• 2011

The rupture disc shapes of bulkhead type pulse separation device(PSD) are designed for new dual pulse rocket motor. Before final design PSD, that three different rupture disc are tested and confirmed the performance of the discs. Through analyzing the test results the PSD decides, two rupture disc shapes with flow holes of eight circles and eight trapezoids.

• Proceedings of the KIPE Conference
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• 2017.11a
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• pp.109-110
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• 2017

본 논문에서는 듀얼 액티브 브릿지에서 SPWM(Single Pulse Width Modulaton)과 DPWM(Dual Pulse Witdh Modulation)을 적용하였을 때, 인덕터 전류의 특성을 비교하고자 한다. 인덕터 전류의 특성을 이론적으로 분석하고, 실험을 통해서 결과를 분석하였다.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.1
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• pp.98-106
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• 2022

To develop reliable dual pulse rocket motor, vacuum ignition performance at high altitude and design stability for rupture pressure of the Pulse Separation Device(PSD) are required. In this study, rupture pressure analysis method for the membrane type PSD of the dual pulse rocket motor was developed. The PSD rupture pressure formulation was derived from strain-pressure relationships. The PSD vacuum rupture test apparatus and the PSD 1 second vacuum ignition test apparatus were developed, which can simulate the high altitude vacuum environment. Rupture pressure of PSD was analyzed by conducting the PSD vacuum rupture test, and design values of PSD were derived. Finally, vacuum ignition performance and rupture pressure of the designed PSD were validated with PSD 1 second vacuum ignition test.