Equational expression of nonlinear load–deformation relationship of dowelled joint with slotted-in steel plate at various lateral loading angles against the grain direction

When rotational moment is applied to a dowelled joint with a slotted-in steel plate connecting the beam and the column, the lateral loads at the individual dowels are applied at various angles against the grain direction. To design the joint or analyze its rotational performance, properties at various angles are required. The main objective of this study was to create a simulation method for nonlinear load–displacement relationships at various angles of the loading direction against the grain direction. In this study, lateral loading tests of dowelled joints with slotted-in steel plates at angles of 0°, 15°, 30°, 45°, 60°, 75°, and 90° were conducted. The load–displacement relationship was measured, and the initial stiffness, proportional limit load, and yield load were obtained. When adopting Hankinson’s formula for the three characteristics, the values of n were 1.951, 2.052, and 1.912, respectively. The combined use of two empirical formulas (Hankinson’s formula and Foschi’s formula) was attempted, and the simulation results agreed well with the experimental results, which verified the usefulness of the simulation method proposed in this study

Evaluation of withdrawal strength of self-tapping screw inserted into cross-laminated timber with different anatomical aspects: ABSTRACT

The use of cross-laminated timber (CLT) technology is witnessing an upsurge in Japan because of its satisfactory performance under seismic conditions. The withdrawal strength (fax) of a single self-tapping screw (STS) inserted into the CLT was observed using a withdrawal test. The experimental results showed that fax of the partially threaded STS was higher than that of the fully threaded STS when inserted perpendicular to the grain. The empirical model used to predict fax provided in the European standard for the design of timber structures was evaluated by comparing the predicted values with the experimental results, which showed that the empirical model was only suitable for predicting the withdrawal strength of specimens with STSs inserted perpendicular to the grain. Therefore, a new probabilistic model was proposed for specimens inserted with STSs inserted parallel to the grain. The failure modes with respect to the orthotropic anatomy of wood materials were observed.     Keywords: withdrawal strength, probabilistic model, failure mode

THEORETICAL ESTIMATION OF MECHANICAL PROPERTIES OF PLYWOOD-SHEATHED SHEAR WALL WITH COMBINED USE OF ADHESIVE TAPE AND WOOD DOWELS

Shear walls often function as elements that provide resistance to horizontal external forces exerted on wooden frames. Many shear walls with superior strength performance have been developed for this purpose. Amidst this backdrop, we have attempted to develop a shear wall that, in addition to strength performance, decreases the time and labor required for disposal. More specifically, the authors proposed a novel “metalless” shear wall: a shear wall in which industrial double-sided adhesive tape is used to attach plywood to the framework. Also, wood dowels are used as supplementary connectors with the aim of enhancing strength performance. Unlike conventional shear walls that use nails and metal fixtures, separation at the time of disposal is unnecessary, and therefore, disposal time and labor of the wall are anticipated to be significantly decreased. Thus, this study involved demonstrating and verifying a methodof theoretical analysis for the mechanical performance of these kinds of shear walls toward in-plane shear force. Specifically, this study derived a method to estimate the mechanical behavior (load-deformation angle relationship) of plywood-sheathed shear walls based on shear performance obtained from double shear tests of joint specimens with the combined use of adhesive tape and wood dowels. Also, the validity of the method was experimentally verified. The results showed that the method proposed in this study was able to estimate the mechanical behavior and mechanical properties of the newly proposed shear wall, and the validity of the method was confirmed

ENERGETICS APPROACH TO FATIGUE BEHAVIOR OF WOODEN JOINT USING DOUBLE-SIDED ADHESIVE TAPE

The authors have previously studied the possibility of the use of industrial double-sided adhesive tape as a method for jointing wooden panel to wooden framework. The mechanical performance of joints formed by such methods is comparable to that of nailed joint under static load conditions. However, the mechanical performance of such joints has not been evaluated under cyclic load conditions. This study was conducted to investigate this aspect of their performance. Double-shear specimens were prepared by bonding wooden panel to wooden framework using two types of adhesive tape with different substrates. Specimens were also prepared with wooden dowels to strengthen their jointing performance. The joint specimens were subjected to cyclic shear loading testing. The results of the tests were analyzed from an energetics perspective, and the shear deformability of the specimens at failure was estimated. The test results indicate that both the specimens formed using adhesive tape and those formed using wooden dowels had fatigue properties comparable to nailed joint specimens. A tendency for the shear deformability caused by cyclic loading to increase with the stress level was observed. It was possible to estimate the shear deformability by evaluating the energy absorption capacity of the joints from an energetics standpoint

Emphysematous Cystitis in a Patient with Type 2 Diabetes Mellitus

A 62-year-old woman with a history of poorly controlled type 2 diabetes mellitus was admitted to our hospital with a 3-week history of mild fever, vomiting, and anorexia. Abdominal computed tomography (CT) showed bilateral hydronephrosis and gas accumulation in the urinary bladder wall and left ureter. Laboratory tests showed leukocytosis and elevated C-reactive protein level. Urine culture showed heavy growth of Escherichia coli. The final diagnosis was emphysematous cystitis. The patient was treated with systemic antibiotics and drainage using a urethral catheter. The clinical and radiographic findings resolved rapidly, and she was discharged from the hospital on day 28. Emphysematous cystitis is a relatively rare urinary tract infection associated with gas formation, and has the potential for a serious outcome if untreated. Early detection by imaging studies such as CT is important in providing prompt treatment and favorable clinical outcome

Membership Privacy for Asynchronous Group Messaging

The Signal protocol is a secure messaging protocol providing end-to-end encrypted asynchronous communication. In this paper, we focus on a method capable of hiding membership information from the viewpoint of non group members in a secure group messaging (SGM) protocol, which we call membership privacy\u27\u27. Although Chase et al. (ACM CCS 2020) have considered the same notion, their proposal is an extension of Signal so called Pairwise Signal\u27\u27 where a group message is repeatedly sent over individual Signal channels. Thus their protocol is not scalable. In this work, we extend the Cohn-Gordon et al. SGM protocol (ACM CCS 2018), which we call the Asynchronous Ratcheting Trees (ART) protocol, to add membership privacy. We employ a key-private and robust public-key encryption (Abdalla et al., TCC2010/JoC2018) for hiding membership-related values in the setup phase. Furthermore, we concentrate on the fact that a group common key provides anonymity. This fact is used to encrypt membership information in the key update phase. Our extension does not affect the forward secrecy and post-compromise security of the original ART protocol. Our modification achieves asymptotically the same efficiency of the ART protocol in the setup phase. Any additional cost for key update does not depend on the number of group members (specifically, one encryption and decryption of a symmetric key-encryption scheme and one execution of a key-derivation function for each key update are employed). Therefore, the proposed protocol can add membership privacy to the ART protocol with a quite small overhead

Continuous Group Key Agreement with Flexible Authorization and Its Applications

Secure messaging (SM) protocols allow users to communicate securely over an untrusted infrastructure. The IETF currently works on the standardization of secure group messaging (SGM), which is SM done by a group of two or more people. Alwen et al. formally defined the key agreement protocol used in SGM as continuous group key agreement (CGKA) at CRYPTO 2020. In their CGKA protocol, all of the group members have the same rights and a trusted third party is needed. On the contrary, some SGM applications may have a user in the group who has the role of an administrator. When the administrator as the group manager (GM) is distinguished from other group members, i.e., in a one-to-many setting, it would be better for the GM and the other group members to have different authorities. We achieve this flexible autho-rization by incorporating a ratcheting digital signature scheme (Cremers et al. at USENIX Security 2021) into the existing CGKA protocol and demonstrate that such a simple modification allows us to provide flexible authorization. This one-to-many setting may be reminiscent of a multi-cast key agreement protocol proposed by Bienstock et al. at CT-RSA 2022, where GM has the role of adding and removing group members. Although the role of the GM is fixed in advance in the Bienstock et al. protocol, the GM can flexibly set the role depending on the application in our protocol. On the other hand, in Alwen et al.’s CGKA protocol, an external public key infrastructure (PKI) functionality as a trusted third party manages the confidential information of users, and the PKI can read all messages until all users update their own keys. In contrast, the GM in our protocol has the same role as the PKI functionality in the group, so no third party outside the group handles confidential informa-tion of users and thus no one except group members can read messages regardless of key updates. Our proposed protocol is useful in the creation of new applications such as broadcasting services

A Transponder Aggregator with Efficient Use of Filtering Function for Transponder Noise Suppression

Colorless, directionless, and contentionless reconfigurable optical add/drop multiplexing (CDC-ROADM) provides highly flexible physical layer network configuration. Such CDC-ROADM must operate in multiple wavelength bands which are being increasingly implemented in optical transmission systems. The operation in C+L bands requires switch devices used in CDC-ROADM to also be capable of multiband operation. Recent studies on wavelength division multiplexing (WDM) systems have pointed out the impact of amplified spontaneous emission (ASE) noise generated by signals of different wavelengths, which causes OSNR degradation. Therefore, it is desirable to filter out the ASE noise from different transponders when multiplexing multiple wavelengths at the transmitter side, especially in a system with non-wavelength selective combiners such as directional couplers and multicast switches. The use of transponder aggregators with filtering functions, such as the M x N wavelength selective switch (WSS), is preferable for this filtering. However, the downside of these devices is that it is difficult to provide economical multiband support. Therefore, we propose an economical transponder aggregator configuration by allowing a certain amount of ASE superposition and reducing the number of filtering functions. In this paper, we fabricated a prototype of the proposed transponder aggregator by combining silica-based planar lightwave circuit technology and C+L band WSS, both commercially available, and verified its feasibility through transmission experiments. The novel transponder aggregator is a practical solution for a multiband CDC-ROADM system with improved OSNR performance.Comment: 10 pages, 11 figures. Submitted to IEEE Journal of Lightwave Technology for possible publicatio

Output Prediction Attacks on Block Ciphers using Deep Learning

Cryptanalysis of symmetric-key ciphers, e.g., linear/differential cryptanalysis, requires an adversary to know the internal structures of the target ciphers. On the other hand, deep learning-based cryptanalysis has attracted significant attention because the adversary is not assumed to have knowledge about the target ciphers with the exception of the algorithm interfaces. Such cryptanalysis in a blackbox setting is extremely strong; thus, we must design symmetric-key ciphers that are secure against deep learning-based cryptanalysis. However, almost previous attacks do not clarify what features or internal structures affect success probabilities. Although Benamira et al. (Eurocrypt 2021) and Chen et al. (ePrint 2021) analyzed Gohr’s results (CRYPTO 2019), they did not find any deep learning specific characteristic where it affects the success probabilities of deep learning-based attacks but does not affect those of linear/differential cryptanalysis. Therefore, it is difficult to employ the results of such cryptanalysis to design deep learning-resistant symmetric-key ciphers. In this paper, we propose deep learning-based output prediction attacks in a blackbox setting. As preliminary experiments, we first focus on two toy SPN block ciphers (small PRESENT-[4] and small AES-[4]) and one toy Feistel block cipher (small TWINE-[4]). Due to its small internal structures with a block size of 16 bits, we can construct deep learning models by employing the maximum number of plaintext/ciphertext pairs, and we can precisely calculate the rounds in which full diffusion occurs. Next, based on the preliminary experiments, we explore whether the evaluation results obtained by our attacks against three toy block ciphers can be applied to block ciphers with large block sizes, e.g., 32 and 64 bits. As a result, we demonstrate the following results, specifically for the SPN block ciphers: First, our attacks work against a similar number of rounds that the linear/differential attacks can be successful. Next, our attacks realize output predictions (precisely ciphertext prediction and plaintext recovery) that are much stronger than distinguishing attacks. Then, swapping or replacing the internal components of the target block ciphers affects the average success probabilities of the proposed attacks. It is particularly worth noting that this is a deep learning specific characteristic because swapping/replacing does not affect the average success probabilities of the linear/differential attacks. Finally, by analyzing the influence of the differences in the characteristics of three S-boxes (i.e., the original PRESENT S-box and two known weak S-boxes) on deep learning specific characteristics, we clarify that the resistance of the target ciphers to differential/linear attacks can affect the success probability of deep learning-based attacks. We also confirm whether the proposed attacks work on the Feistel block cipher. We expect that our results will be an important stepping stone in the design of deep learning-resistant symmetric-key ciphers

Role of Neuroimaging on Differentiation of Parkinson’s Disease and Its Related Diseases

An accurate diagnosis of Parkinson’s disease (PD) is a prerequisite for therapeutic management. In spite of recent advances in the diagnosis of parkinsonian disorders, PD is misdiagnosed in between 6 and 25% of patients, even in specialized movement disorder centers. Although the gold standard for the diagnosis of PD is a neuropathological assessment, neuroimaging has been playing an important role in the differential diagnosis of PD and is used for clinical diagnostic criteria. In clinical practice, differential diagnoses of PD include atypical parkinsonian syndromes such as dementia with Lewy bodies, multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration, caused by a striatal dopamine deficiency following nigrostrial degeneration. PD may also be mimicked by syndromes not associated with a striatal dopamine deficiency such as essential tremor, drug-induced parkinsonism, and vascular parkinsonism. Moreover, difficulties are associated with the clinical differentiation of patients with parkinsonism from those with Alzheimer’s disease. In this review, we summarize the typical imaging findings of PD and its related diseases described above using morphological imaging modalities (conventional MR imaging and neuromelanin MR imaging) and functional imaging modalities (99mTc-ethyl cysteinate dimer perfusion single photon emission computed tomography, 123I-metaiodobenzylguanidine myocardial scintigraphy, and 123I-FP-CIT dopamine transporter single photon emission computed tomography) that are clinically available in most hospitals. We also attempt to provide a diagnostic approach for the differential diagnosis of PD and its related diseases in clinical practice