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This study investigated the impact of driving style and traffic condition on emissions and fuel consumption using a selected range of real-world transient drive cycles, using both diesel and a diesel–biodiesel blend on a turbocharged diesel engine. Using 30 drivers, real-world measurements were performed with a Hyundai iLoad 2017 automatic diesel van in a typical urban driving route in Brisbane. From the on-road measurements, six different transient cycles were developed based on different driving styles (timid, normal and aggressive) and traffic conditions (off-peak and peak hour) according to the guidelines presented in the US Code of Federal Regulations, Title 40, Part 86. In this paper, engine operating parameters (engine speed and load), gaseous emissions (NOx, CO and CO2), particulate matter emissions (PM and PN), and fuel consumption were investigated in relation to driving style, traffic condition and fuel type, using different data analysis methods such as Kernel density estimation (KDE) and Analysis of variance (ANOVA). The investigation revealed that engine behaviour during real-world transient operation is entirely different from the steady-state operation, which results in significantly high emissions. Driving style has a strong influence on emissions, evident from emission results as well as ANOVA analysis. Aggressive driving generates a higher number of transient micro-trips which ultimately results in an overshoot in emissions. A moderate increment in CO2 and NOx emissions (up to 37% and 38% respectively) and a high increment in CO emission (up to 88%) was observed for the aggressive cycles. PM and PN emission increased significantly (up to 112% and 538% respectively) for aggressive cycles. Biodiesel showed a promising impact in PM and PN emission reduction (up to 71% PM and 68% PN respectively) regardless of the driving style and traffic condition. In general, off-peak cycles demonstrated more severe re

This paper analyses the resistance of certain keystream generators against algebraic attacks, namely generators consisting of a nonlinear feedback shift register, a linear feedback shift register and a filter function. We show that poorly chosen filter functions make such designs vulnerable to new algebraic attacks, using a divide and conquer approach that targets the LFSR first. This approach provides efficient LFSR initial state recovery followed by partial NFSR initial state recovery. We apply our algebraic attacks to modified versions of the Grain family of stream ciphers. Our analysis shows that, despite the highly nonlinear filter functions used in these variants, the LFSR state can be recovered using our algebraic attack much faster than exhaustive search. Following this, the NFSR initial state can be partially recovered, leaving a smaller subset of NFSR stages to be exhaustively searched. This investigation highlights the importance of the filter function in keystream generators with a "Grain-like'" structure, and demonstrates that many functions previously considered secure are vulnerable to this attack.

This paper presents an investigation into the resistance of linearly filtered nonlinear feedback shift registers (LF-NFSRs) against distinguishing attacks. We formalise the method described by Orumiehchiha, Pieprzyk, Steinfeld and Bartlett and then extend it to develop a more efficient, systematic framework for accurately distinguishing an arbitrary LF-NFSR. Our method is then generalised to distinguish arbitrary LF-NFSRs with regularly decimated output sequences. The proposed method is demonstrated through application to the example LF-NFSR used by Orumiehchiha et al. with improved results. Additionally, our new method can be accurately applied to much larger registers and can predict how much output is needed to find the strongest bias. To demonstrate this, we derive time and keystream requirement estimates for our attacks on each variant of the Grain family of stream ciphers under weak key-IV pairs.

We show that a particular class of stream ciphers - namely those in which the output function contains a bitwise AND operation - are susceptible to a differential fault attack using random faults. Several finalists and other candidates from the recent CAESAR competition fall into this category, including the AEGIS variants, Tiaoxin and the MORUS family. Attack outcomes range from key or full state recovery for Tiaoxin, to full state recovery for the AEGIS family and partial state recovery for MORUS. We present attack requirements and success probabilities on these ciphers, along with design considerations to mitigate against this attack.

This paper analyses the security of the lightweight cryptographic algorithm Fountain (V1), which is a candidate in the current NIST competition for such ciphers. We examine the Boolean functions used in Fountain for state update and output. We show that correlations exist between S-box functions and some register stages that may lead to correlation attacks if certain update functions are detectable. We also show that the state update function avoids state convergence in any phase of cipher operation, but state collisions may be forced in one bit position, for select states, by manipulating the associated data or plaintext.

In this paper, we show that stream ciphers with a particular form of ciphertext output function are vulnerable to differential fault attacks using random faults. The CAESAR competition candidates Tiaoxin-346 and AEGIS-128L both fall into this category, and we show that our attack can be used to recover the secret key of Tiaoxin-346 and the entire state of AEGIS-128L with practical complexity. In the case of AEGIS-128L, the attack can be applied in a ciphertext-only scenario. Our attacks are more practical than previous fault attacks on these ciphers, which assumed bit-flipping faults. Although we also consider other ways of mitigating our attacks, we recommend that cipher designers avoid the form of ciphertext output function that we have identified.

AEZ is a block cipher mode based on AES which uses three 128-bit keys. The algorithm has been updated several times during the three rounds of the CAESAR cryptographic competition. Cryptanalytic results presented on AEZ to date do not breach its security. This paper describes a fault injection analysis on AEZ. We focus on analysing AEZ v4.2 but also investigate the applicability of these analyses to the recent version AEZ v5. This paper shows that all three 128-bit keys in AEZ v4.2 can be uniquely retrieved using only three random-valued single byte fault injections. A similar approach using four fault injections can uniquely recover all three keys of AEZ v5. The feasibility of this fault injection methodology has been proven against AES in previous works.

This paper describes two different fault injection attacks on the authenticated encryption stream cipher Tiaoxin-346, a third round candidate in the CAESAR cryptographic competition. The first type of fault injection uses a bit-flipping fault model to conduct a forgery attack. The number of faulty bits required for this forgery attack is twice the number of bit modifications made in the input message. The second type of fault injection uses a random fault model in a differential fault attack to recover the secret key of the cipher. A successful attack can be performed with 36 random multi-byte faults and a computational complexity of 236. This second attack improves on the previous key recovery attack of Dey et. al., as the random fault model we use is more practical than the bit flipping model used in their attack.

In this article, we analyse a block cipher mode of operation for authenticated encryption known as ++AE (plus-plus-AE). We show that this mode has a fundamental flaw: the scheme does not verify the most significant bit of any block in the plaintext message. This flaw can be exploited by choosing a plaintext message and then constructing multiple forged messages in which the most significant bit of certain blocks is flipped. All of these plaintext messages will generate the same authentication tag. This forgery attack is deterministic and guaranteed to pass the ++AE integrity check. The success of the attack is independent of the underlying block cipher, key or public message number. We outline the mathematical proofs for the flaw in the ++AE algorithm. We conclude that ++AE is insecure as an authenticated encryption mode of operation.

This paper investigates the application of fault attacks to the authenticated encryption stream cipher algorithm MORUS. We propose fault attacks on MORUS with two different goals: one to breach the confidentiality component, and the other to breach the integrity component. For the fault attack on the confidentiality component of MORUS, we propose two different types of key recovery. The first type is a partial key recovery using a permanent fault model, except for one of the variants of MORUS where the full key is recovered with this model. The second type is a full key recovery using a transient fault model, at the cost of a higher number of faults compared to the permanent fault model. Finally, we describe a fault attack on the integrity component of MORUS, which performs a forgery using the bit-flipping fault model.

This study investigated particle and gaseous emission factors from a large cargo vessel for her whole voyage including at berth, manoeuvring and cruising. Quantification of these factors assists in minimising the uncertainty in the current methods of exhaust gas emission factor estimation. Engine performance and emissions from the main marine engine were measured on-board while the ship was manoeuvring and cruising at sea. Emissions of an auxiliary engine working at 55% of maximum continuous rating (MCR) were measured when the ship was at actual harbour stopovers. Gaseous and particle emission factors in this study are presented in g kWh-1 or # kWh-1, and compared with previous studies. Results showed that the SO2 emission factor is higher than that of previous studies due to the high sulphur content of the fuel used. The particle number size distributions showed only one mode for different operating conditions of the ship, with a peak at around 40-50 nm, which was dominated by ultrafine particles. Emission factors of CO, HC, PM and PN observed during ship manoeuvring were much higher than that of those recorded at cruising condition. These findings highlight the importance of quantification and monitoring ship emissions in close proximity to port areas, as they can have the highest impact on population exposure.