• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.40-57
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• 2004

The effects of triple (pilot, main and after) injection on combustion and emission characteristics in a HSDI (High-Speed Direct Injection) diesel engine were investigated using a single-cylinder optical diesel engine equipped with a common-rail injection system. The pilot injection affected the spray and combustion evolution of the following main injection. It was found that the pilot injection reduced the ignition delay, which led to lowered NOx (Nitric Oxides) level, and increased IMEP (Indicated Mean Effective Pressure) due to slow combustion pace during an expansion stroke. The after-injection was shown to be effective in reducing PM (Particulate Matter) even when a small amount of fuel was added. The results suggest that a proper combination of individual injection strategy could bring about a good synergetic effect on engine performance and emission.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.4
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• pp.709-717
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• 2012

The round reduction on block cipher is a fault injection attack in which an attacker inserts temporary errors in cryptographic devices and extracts a secret key by reducing the number of operational round. In this paper, we proposed an improved round reduction method to retrieve master keys by injecting a fault during operation of loop statement in the Triple DES. Using laser fault injection experiment, we also verified that the proposed attack could be applied to a pure microprocessor ATmega 128 chip in which the Triple DES algorithm was implemented. Compared with previous attack method which is required 9 faulty-correct cipher text pairs and some exhaustive searches, the proposed one could extract three 56-bit secret keys with just 5 faulty cipher texts.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.2
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• pp.91-100
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• 2011

The Triple Data Encryption Algorithm (Triple DES) is an international standard of block cipher, which composed of two encryption processes and one decryption process of DES to increase security level. In this paper, we proposed a Differential Fault Analysis (DFA) attack to retrieve secret keys using reduction of last round execution for each DES process in the Triple DES by fault injections. From the simulation result for the proposed attack method, we could extract three 56-bit secret keys using exhaustive search attack for $2^{24}$ candidate keys which are refined from about 9 faulty-correct cipher text pairs. Using laser fault injection experiment, we also verified that the proposed DFA attack could be applied to a pure microprocessor ATmega 128 chip in which the Triple DES algorithm was implemented.

• Journal of Advanced Navigation Technology
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• v.14 no.1
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• pp.87-92
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• 2010

The design of avionic embedded systems requires high-dependability. In this paper, we studied the dependability of the triple modular redundancy (TMR) hardware for highly reliable aviation embedded system. In order to evaluate the dependability of the base ARM processor and the TMR ARM processor, we developed the simulation model of the reduced ARM and TMR ARM processors and performed the simulation fault injection for the analysis of the dependability of the two targets. In the fault injection experiments, we calculated the error recovery rate of the two the processor models. From the experimental results, we could confirm that the reliability of the TMR ARM processor was greater than the single ARM processor by ten times in some cases.

• Transactions of the KSME C: Technology and Education
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• v.1 no.2
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• pp.167-177
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• 2013

The use of mechanical anastomosis coupler instead of sutures has been increasing in microvascular anastomosis surgery. However, non-biodegradable anastomosis coupler has problems such as not only inflammatory reaction but also remaining permanently in operation wound. Therefore, we fabricated biodegradable anastomosis coupler using injection molding process to overcome the limitation of non-biodegradable anastomosis coupler. In various injection molding process conditions, the shrinkage was calculated with different cylinder temperatures and injection molding pressures and anastomotic strength was measured. As a result, changes in shrinkage hole part larger than the pin part. In addition, the shrinkage in the cylinder at higher temperatures increase. However, the higher the injection pressure, shrinkage tends to decrease, respectively. In-vitro degradation behavior of PCL anastomotic coupler evaluated for 12 weeks, water uptake was increased and molecular weight was accompanied by a reduction in mass of the biological degradation and reduction of anastomotic strength was confirmed. However, decreased levels of anastomotic strength enough to exceed the requirements of preclinical surgery, PCL microvascular anastomosis coupler suitable candidate materials that could identify.

• ETRI Journal
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• v.39 no.4
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• pp.605-613
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• 2017

Simulated fault injection (SFI) is widely used to assess the effectiveness of fault tolerance mechanisms in safety-critical embedded systems (SCESs) because of its advantages such as controllability and observability. However, the long test time of SFI due to the large number of test cases and the complex simulation models of modern SCESs has been identified as a limiting factor. We present a method that can accelerate an SFI tool using a checkpoint forwarding (CF) technique. To evaluate the performance of CF-based SFI (CF-SFI), we have developed a CF mechanism using Verilog fault-injection tools and two systems under test (SUT): a single-core-based co-simulation model and a triple modular redundant co-simulation model. Both systems use the Verilog simulation model of the OpenRISC 1200 processor and can execute the embedded benchmarks from MiBench. We investigate the effectiveness of the CF mechanism and evaluate the two SUTs by measuring the test time as well as the failure rates. Compared to the SFI with no CF mechanism, the proposed CF-SFI approach reduces the test time of the two SUTs by 29%-45%.

• Journal of ILASS-Korea
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• v.18 no.4
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• pp.176-181
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• 2013

In this study, injection quantity, rate and spray image of multiple injections which are important design parameters for a piezo type injector have been investigated. Interval of injections and a number of injections in multiple injection strategy has been controlled to verify interaction of each injection. Spray characteristics of multiple injections have been researched through optical process with a high speed camera in a high pressure chamber. In addition, a method of RMS(Root Mean Square) process has been used for comprehending the distribution of injection easily. As a result, in case of piezo type injector, characteristics of injection quantity according to charging voltage and the difference of injection quantity between single and triple injection were confirmed. Also, injection rate for increasing injection duration was confirmed. And spray characteristics of multiple injections were improved; multiple injections were possible in a shorter time interval between each injection. With this study, a possibilities of more accurate multiple injection control would be expected.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.347-354
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• 2002

In this paper, when structures are constructed in the soft ground with poor bearing capacity at Incheon International Airport(railroad area), as for the grouting columns built In soft ground by high pressure jet grouting with Triple tube rod(super injection grouting), the effects on reinforcement and bearing capacity of ground are investigated. A unconfined compressive strength tests has been performed on the specimens sampled from the grouting columns and a mass plate bearing test has been performed on a grouting column. The test results show that super injection grouting has a sufficient effect on composite ground improved of foundation ground and reatraint of settlement of structure.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2008.05a
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• pp.23-29
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• 2008

- High Density Plasma Source-CCP-Dual/Triple, RF Frequency Control - Radical/Flux Analysis - Low Pressure Process - Chamber Design (Process gap/Wall gap) - Chamber Temp. Control. - ESC Dielectric Materials - Uniform Gas Injection

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.5
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• pp.27-33
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• 2011

At FDTC'05 and CISC-W'10, the authors showed that if they decrease the number of rounds of AES and Triple-DES by using the fault injections, it is possible to recover the secret key of the target algorithms, respectively. In this paper, we propose a key recovery attack on HMAC by using the main idea of these attacks. This attack is applicable to HMAC based on MD-family hash functions and can recover the secret key with the negligible computational complexity. Particularly, the attack result on HMAC-SHA-2 is the first known key recovery attack result on this algorithm.