Equality Test Research Articles

Signatures of algebraic curves via numerical algebraic geometry

We apply numerical algebraic geometry to the invariant-theoretic problem of detecting symmetries between two plane algebraic curves. We describe an efficient equality test which determines, with “probability-one”, whether or not two rational maps have the same image up to Zariski closure. The application to invariant theory is based on the construction of suitable signature maps associated to a group acting linearly on the respective curves. We consider two versions of this construction: differential and joint signature maps. In our examples and computational experiments, we focus on the complex Euclidean group, and introduce an algebraic joint signature that we prove determines equivalence of curves under this action and the size of a curve's symmetry group. We demonstrate that the test is efficient and use it to empirically compare the sensitivity of differential and joint signatures to different types of noise.

Group Public Key Encryption with Equality Test under Standard Model

Group public key encryption with equality test (G-PKEET) scheme supports group granularity authorization on the equality test. An authorized proxy is able to check whether two ciphertexts belonging to the same group are encrypted from identical plaintext without decrypting them. However, in indistinguishability-based security notion, current existing PKEET and G-PKEET schemes do not allow adversary to invoke equality test as a service. In contrast, under practical circumstance, an adversary is probably able to exploit the equality test service offered by proxy to decipher a ciphertext, leading to unexpected and unwanted privacy leakage. In this paper, we propose a security definition that includes the abovementioned adversary ability. Through extending the functionality of current G-PKEET scheme, we design a concrete scheme that satisfies our new security definition. Furthermore, our G-PKEET scheme is the first G-PKEET scheme whose security properties can be proved under the standard model.

Investigating Temporal Kinematic Differences Caused by Unexpected Stimulation during Gait Termination through the Waveform-Level Variance Equality Test.

The efficacy of the variance equality test in steady-state gait analysis is well documented; however, temporal information on where differences in variability occur during gait subtasks, especially during gait termination caused by unexpected stimulation, is poorly understood. Therefore, the purpose of the current study was to further verify the efficacy of the waveform-level variance equality test in gait subtasks by comparing temporal kinematical variability between planned gait termination (PGT) and unplanned gait termination (UGT) caused by unexpected stimulation. Thirty-two asymptomatic male subjects were recruited to participate in the study. A Vicon motion capture system was utilized to measure lower extremity kinematics during gait termination tasks with and without unexpected stimulation conditions. The F-statistic for each interval of the temporal kinematic waveform was compared to the critical value using a variance equality test to identify significant differences in the waveform. Comparative tests between two types of gait terminations found that subjects may exhibit greater kinematics variance in most lower limb joints during UGT caused by unexpected stimulation (especially at stimulus delay and reaction phases). Significant greater variances during PGT were exhibited only in the MPJ sagittal and frontal planes at the early stimulus delay phase (4-15% and 1-15%). This recorded dataset of temporal kinematic changes caused by unexpected stimuli during gait termination is essential for interpreting lower limb biomechanical function and injury prediction in relation to UGT. Given the complexity of the gait termination task, which involves both internal and external variability, the variance equality test can be used as a valuable method to compare temporal differences in the variability of biomechanical variables.

Lattice-based public-key encryption with equality test supporting flexible authorization in standard model

As cloud computing has developed rapidly, outsourcing data to cloud servers for remote storage has become an attractive trend. However, when cloud clients store their data in the cloud, the security and privacy of cloud data would be threatened due to accidental corruptions or purposive attacks caused by a semi-trusted cloud server. The widely used method of addressing the security and privacy of cloud data is to store encrypted data instead of plain data. As the resulting system is unusable, since the cloud can no longer search throughout the data, new cryptographic primitive such as public-key encryption with equality test (PKEET) has been introduced. PKEET has many interesting applications such as keyword search on encrypted data, encrypted data partitioning for efficient encrypted data management, personal health record systems, spam filtering in encrypted email systems and so forth. PKEET allows checking whether two ciphertexts encrypted under different public keys contain the same message or not. However, unrestricted access to equality tests can reveal information about the underlying data. This is not acceptable in respect of users' privacy. In 2015, Ma et al. introduce the notion of PKEET with flexible authorization (PKEET-FA) which strengthens privacy protection. Since 2015, there are several follow-up works on PKEET-FA. However, all are secure in the random oracle model and vulnerable to quantum attacks. In this paper, we provide two constructions of quantum-safe PKEET-FA secure in the standard model based on the hardness assumptions of integer lattices and ideal lattices. Finally, we implement the PKEET-FA scheme over ideal lattices.

Achieving Efficient and Privacy-Preserving Dynamic Skyline Query in Online Medical Diagnosis

Wireless body area network (WBAN) and big data techniques indubitably enable the online medical diagnosis system to be more practical. In the system, to make a more accurate diagnosis, doctors wish to obtain some archived medical data records, which are similar to the sensed patient data, to learn from the prior diagnoses. As a practically useful similarity search, the dynamic skyline query can provide doctors with similar data records having all possible relative weights of attributes. Driven by the powerful cloud, the data owner often outsources encrypted data and the corresponding services, e.g., dynamic skyline query services here, to a third-party cloud. As a result, it is required to perform the dynamic skyline query over encrypted data. However, existing schemes are either insecure or inefficient. To address the issue, in this article, we propose an efficient and privacy-preserving dynamic skyline query scheme and use it in an online medical diagnosis system. Specifically, based on symmetric homomorphic encryption (SHE), we present a set of efficient and secure protocols to achieve various operations, such as less than comparison, equality test, and dominance determination, without leaking any sensitive information to the cloud. With these secure protocols, we carefully design our dynamic skyline query scheme to attain full security and high efficiency at the same time. Detailed security analysis shows that our proposed scheme is indeed privacy-preserving. With extensive experimental evaluations, we show that our proposed scheme outperforms the alternative scheme by two orders of magnitude in the computational cost and at least <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$8.1\times $ </tex-math></inline-formula> in the communication cost.

Public Key Encryption with Equality Test in a Cloud Environment

With the rapid development and wide application of cloud computing and 5G communication, the number of mobile users is increasing rapidly, meaning that cloud storage services are receiving more and more attention. The equality test technology of retrievable encrypted data has become a hot research topic among scholars in recent years. In view of the problem of offline keyword-guessing attacks (KGAs) caused by collusion between internal servers and users, a public key encryption with equality test scheme (RKGA-CET) with higher security against KGAs is proposed. Based on the assumed difficulty of the discrete logarithm problem (DLP) and the properties of bilinear mapping, a specific encryption algorithm that encrypts the keyword twice is designed. In the first encryption stage, we convert the keyword according to the property of isomorphism of a finite field. In the second encryption stage, we encrypt the converted keyword vector and embed the user’s private key, and then perform the equality test. The algorithm ensures that the adversary cannot generate legal ciphertexts and implement KGAs when the secondary server is offline. At the same time, the algorithm also supports two authorization modes, in which case users can flexibly choose the corresponding authorization mode according to their own needs. Performance analysis shows that this scheme has overall superiority compared with other similar ones.

Randomized prospective clinical trial of class II restorations using flowable bulk-fill resin composites: 4-year follow-up.

This randomized, prospective, and split-mouth study aimed to evaluate flowable bulk-fill resin composites in class II restorations, comparing it with a conventional layering technique after 4-year follow-up. Fifty-three subjects received three class II restorations according to the restorative systems: conventional microhybrid composite resin (PA - Peak Universal + Amelogen Plus, Ultradent); flowable bulk-fill and nanoparticulate composite resins (ABF - Adper Single Bond 2 + Filtek Bulk Fill Flow + Filtek Z350XT, 3M/Espe); and flowable bulk-fill and microhybrid composite resins, (XST - XP Bond + SDR + TPH3, Dentsply). The clinical performance and interproximal contacts were evaluated. Statistical analyses were performed using the Kaplan-Meier, equality test of two proportions, Friedman, Wilcoxon, Kruskal-Wallis, Mann-Whitney, and Logistic regression analysis tests (alpha = 0.05). In total, 106 restorations were evaluated at 4 years. Both systems with bulk-fill composites presented higher marginal discoloration than PA. About surface texture, ABF restorative system showed superior bravo scores being statistically similar to XST. Better performance for wear and surface staining was found for XST restorative system. All restorative systems resulted in the decreased interproximal contacts, occurring early for XST. The restorative systems that used flowable bulk-fill resin composites showed satisfactory clinical performance compared with conventional resin composite after 4 years. All restorative systems had decreased proximal contact after 4 years. Initial marginal discoloration was observed in more than 50% of class II restorations performed with restorative systems that used flowable bulk-fill resin composite. All restorative systems had decreased proximal contact strength over time.

Group public key encryption supporting equality test without bilinear pairings

In cloud computing scenarios, it is a common approach to encrypt the data before uploading in order to maintain the privacy. Public key encryption with equality test (PKEET) provides a generic solution to equality comparisons on encrypted data. Considering the practical requirements of PKEET in group user scenarios, Ling et al. presented a group public key encryption scheme with equality test (G-PKEET) by utilizing the computationally expensive bilinear pairing operations. In this paper, we propose an efficient and verifiable group public key encryption with equality test construction without bilinear pairings (GPKEET/BP). Our proposal is developed from a basic observation that two points determine a straight line, and is proven to be indistinguishable against the chosen-ciphertext attacks (IND-CCA) in the random oracle model under the computational Diffie-Hellman (CDH) assumption. Theoretical analysis shows that our construction only involves several modular exponentiations in the encryption, decryption and test algorithms. The theoretical results are well supported by experimental simulations, which show that the test algorithm of GPKEET/BP performs about 92% faster than that of Ling et al.’s scheme. So our GPKEET/BP scheme turns out to be better suited for group ciphertext equality test situations.

PENGARUH PENGGUNAAN MODEL ADVANCE ORGANIZER BERMEDIA PETA KONSEP TERHADAP KEMAMPUAN MENGANALISIS MATERI SEJARAH SISWA SMA

The purpose of this study to determine the effect of the use of advance organizer teaching model bermedia concept maps on the ability to analyze the historical material class X SMA IPS second semester of the country 1 Punggur the Academic Year 2016/2017. This research uses quasi studies (Quasi Experiment), to form Nonequivalent control group design. Samples were selected using cluster random sampling and testing done outside of class X IPS4 sample of classes to 34 students. Validity and Reliability through SPSS 16 results are abnormal and homogeneous. test hypotheses on the equality test two averages using SPSS 16 with the test method K Independent Samples Tests to get the sig 0.006 (&lt;0.05). Having in mind there are further differences in the two different test arithmetic average using SPSS 16 with the test method Two Independent Samples Tests and earn an average yield of 42.97 experimental classroom learning and to control class 29.40. The conclusion of this study is that there is a significant positive influence and advance the use of the learning model of media organizer concept maps on the ability to analyze the historical material class X IPS second semester of SMA Negeri 1 Punggur in academic year 2016/2017.

Cross-domain encryption scheme with equality test for wireless body area networks

Cross-domain encryption scheme with equality test for wireless body area networks

Disentangling Drivers of Food Waste in Households: Evidence from Nigeria.

Food waste is a burden on society in terms of the money wasted. There is limited information on the determinants of food waste and the amount lost to food waste by households as most previous studies were on post-harvest losses. Hence, determinants of food waste among households in Kogi West Senatorial District, Kogi State Nigeria were investigated. A three-stage sampling technique was used to select the respondents, while a structured questionnaire was used for data collection. Data were analyzed using Tobit regression and an equality test. The study revealed that food waste was higher in male headed households. The average monthly food waste proportion among urban households was significantly higher than that of rural households. The estimated amounts lost to food waste per month were ₦2103 and ₦5530 for the rural and urban households, respectively. These represented 7.2% and 13.1% of the total expenditure on food per month for rural and urban households, respectively. Among rural households, leftovers of food and lack of proper storage were the main reasons for food waste, while leftovers of food and preparation of food more than needed were the reasons for food waste among urban households. The sex of respondents, work experience, and monthly income influenced the proportion of food waste among rural households, while the dependency ratio, monthly income, and monthly food expenditure were the determinants of proportion of food waste among the urban households. Non-Governmental Organization efforts through sensitization campaigns focused on the need to reduce food waste, especially among urban households, would help to reduce the financial burden of food waste on households.

Public Key Encryption With Equality Test Supporting Flexible Designated Authorization in Cloud Storage

Public Key Encryption With Equality Test Supporting Flexible Designated Authorization in Cloud Storage

Traceable Scheme of Public Key Encryption with Equality Test.

Public key encryption supporting equality test (PKEwET) schemes, because of their special function, have good applications in many fields, such as in cloud computing services, blockchain, and the Internet of Things. The original PKEwET has no authorization function. Subsequently, many PKEwET schemes have been proposed with the ability to perform authorization against various application scenarios. However, these schemes are incapable of traceability to the ciphertexts. In this paper, the ability of tracing to the ciphertexts is introduced into a PKEwET scheme. For the ciphertexts, the presented scheme supports not only the equality test, but also has the function of traceability. Meanwhile, the security of the proposed scheme is revealed by a game between an adversary and a simulator, and it achieves a desirable level of security. Depending on the attacker’s privileges, it can resist OW-CCA security against an adversary with a trapdoor, and can resist IND-CCA security against an adversary without a trapdoor. Finally, the performance of the presented scheme is discussed.

Monitoring the CO2 Emission Trajectory and Reduction Effects by ETS and Its Market Performances for Pre- and Post-pandemic China.

The COVID-19 pandemic has caused great shocks on economic activities and carbon emissions. This paper aims to monitor the CO2 emission trajectory in China before and after the pandemic outbreak, and analyze the emission reduction effects by ETS and its market performances, which are important determinants underlying the trajectory and key drivers for emission reductions. We firstly find out a rather consistent trajectory of CO2 emissions in pre- and post-pandemic China over a 2-year time horizon, using the near-real-time datasets of daily CO2 emissions by Carbon Monitor and applying the Cox-Stuart trend test and mean equality test. We then examine the emission reduction effects by China's carbon ETS and its pilot market performances, using the methodologies of DID and PSM-DID as well as pre-pandemic region-level emission datasets by CEADs. Furthermore, it's found that the ETS pilot markets, which are immature with defects, have been performing more vulnerably in terms of liquidity and transaction continuity under pandemic shocks, thus undermining the emission reduction effects by ETS. These findings are providing insights into further mechanism design of the carbon ETS to the end of steady emission reductions even under shocks for post-pandemic China. It's of particular importance now that the nationwide market has been launched and needs to be enhanced based on lessons learned.

Mean Equality Tests for High-Dimensional and Higher-Order Data with k-Self Similar Compound Symmetry Covariance Structure

An extension of the D2 test statistic to test the equality of mean for high-dimensional and k-th order array-variate data using k-self similar compound symmetry (k-SSCS) covariance structure is derived. The k-th order data appear in many scientific fields including agriculture, medical, environmental and engineering applications. We discuss the property of this k-SSCS covariance structure, namely, the property of Jordan algebra. We formally show that our D2 test statistic for k-th order data is an extension or the generalization of the D2 test statistic for second-order data and for third-order data, respectively. We also derive the D2 test statistic for third-order data and illustrate its application using a medical dataset from a clinical trial study of the eye disease glaucoma. The new test statistic is very efficient for high-dimensional data where the estimation of unstructured variance-covariance matrix is not feasible due to small sample size.

Public Key Encryption with Authorized Equality Test on Outsourced Ciphertexts for Cloud-Assisted IoT in Dual Server Model

In cloud computing, the outsourced data face many privacy and security threats. To allow the cloud server to perform comparison, search, and classification on outsourced ciphertexts while simultaneously providing privacy guarantee, the encryption method that supports the ciphertext equality test is considered as a promising way. Users are able to authorize the cloud server to conduct the ciphertext equality test, so that two ciphertexts can be determined whether they encrypt the same message without being decrypted. In this process, users do not need to retrieve, decrypt, and then perform comparison on data; thus, the computing and communication efficiency can be greatly improved, and the privacy of user data can be guaranteed at the cloud server side. However, existing encryption schemes supporting authorized ciphertext equality test in the single server model cannot resist the keyword guessing attacks, and the solutions in the dual server model do not provide simultaneous authorization on two servers. To address these issues, this paper proposes a public key encryption scheme supporting authorized equality test on ciphertexts in the dual server model (PKE-AUT), where the primary server and secondary server must get the authorization from users before performing a sequential equality test on ciphertexts. Security and performance analysis demonstrate that the proposed PKE-AUT scheme not only guarantees the privacy of user data and authorization but also is practical in cloud-assisted IoT-related applications.

Implementation of the DSM-5 and ICD-11 Dimensional Models of Maladaptive Personality Traits Into Pre-bariatric Assessment.

Background: Personality pathology does not have to be a contraindication to a bariatric surgery if a proper pre-surgical assessment is done. Indicating subgroups of patients with their specific needs could help tailor interventions and improve surgical treatment outcomes.Objectives: Using the Alternative DSM-5 model for personality disorders (AMPD) and the ICD-11 model for PDs to detect subgroups of patients with obesity based on a specific constellation of maladaptive personality traits and the level of overall personality impairment.Methods: 272 consecutively consented patients who underwent a standard pre-surgical psychological assessment. The majority were women (58.0%), age range was 22–79 years (M = 48.06, SD = 10.70). Patients’ average body mass index (BMI) was 43.95 kg/m2. All participants were administered the Personality Inventory for DSM-5 (PID-5) from which Level of Personality Functioning Scale-Self Report (LPFS-SR) and Standardized Assessment of Severity of Personality Disorder (SASPD) scores were gained using the “crosswalk” for common metric for self-reported severity of personality disorder. The k-means clustering method was used to define specific subgroups of patients with obesity and replicated for equality testing to the samples of non-clinical respondents and psychiatric patients.Results: The cluster analysis detected specific groups in the sample of patients with obesity, which differed quantitatively from the samples of non-clinical respondents and psychiatric patients. A vast majority of patients with obesity showed above-average values in most of the PID-5 facets compared to the United States representative general community sample. In two out of the three clusters defined, patients demonstrated moderate (> M + 1.5 × SD) to severe (> M + 2.0 × SD) personality psychopathology within the Detachment and Negative Affectivity domains according to PID-5, which in one of the clusters corresponded to the mild overall impairment in both, LPFS-SR (M = 2.18, SD = 0.27) and SASPD (M = 8.44, SD = 2.38). Moreover, higher levels of psychopathology prove to be associated with higher age and use of psychiatric medication.Conclusions: The dimensional DSM-5 and ICD-11 trait models are suitable procedures for defining specific “characters” of patients in a pre-bariatric setting. As such, they help to identify subgroups of patients with obesity who are different from general population and psychiatric patients. Implications for clinical practice and further research are discussed.

Efficient Public Key Encryption With Outsourced Equality Test for Cloud-Based IoT Environments

Cloud-based Internet of Things (IoT) system is becoming a promising architecture in our modern society. However, cloud-based IoT system brings a number of challenges in the security aspect while improving the efficiency of data analytics. Especially, searching on encrypted data is challenging given today’s technology. Thus searchable encryption has emerged as one of the important research fields. Public key encryption with equality test (PKEET) provides a simple but useful mechanism to cryptographically protect data while keeping it available for equality test on ciphertexts. However, PKEET schemes in the literature are not suitable for cloud-based IoT system with privacy protection enhancement since the untrustworthy cloud server may be interested in query results by itself and hence reveal the private information of data owner out of the expectation of data user. Even worse, it could launch offline message recovery attack (OMRA) based on the returned query results. In this paper, we introduce a new notion of public key encryption with outsourced equality test (PKE-OET) for adapting to cloud-based IoT environments as well as providing a flexible solution to resist against OMRA without taking any information about entrusted parties as input in encryption. We formally define the security model of PKE-OET against three types of adversary including IND-CCA-I, IND-CCA-II and IND-CCA-III. We present a generic PKE-OET construction using a new variant of smooth projective hash function (SPHF) with a novel Lin-Hom property, which is of independent interest. Then we provide an efficient PKE-OET instantiation from Symmetric eXternal Diffie-Helllman (SXDH) assumption and show its practicality for cloud-based IoT environments through a series of experiments on Cloud Server and Raspberry Pi.

More Efficient Tightly-Secure Lattice-Based Ibe with Equality Test

More Efficient Tightly-Secure Lattice-Based Ibe with Equality Test

An Enhanced Privacy Preserving, Secure and Efficient Authentication Protocol for VANET

Vehicular ad hoc networks (VANETs) have attracted growing interest in both academia and industry because they can provide a viable solution that improves road safety and comfort for travelers on roads. However, wireless communications over open-access environments face many security and privacy issues that may affect deployment of large-scale VANETs. Researchers have proposed different protocols to address security and privacy issues in a VANET, and in this study we cryptanalyze some of the privacy preserving protocols to show that all existing protocols are vulnerable to the Sybil attack. The Sybil attack can be used by malicious actors to create fake identities that impair existing protocols, which allows them to imitate traffic congestion or at worse cause an accident that may result in the loss of human life. This vulnerability exists because those protocols store vehicle identities in an encrypted form, and it is not possible to search over the encrypted identities to find fake vehicles. This attack is serious in nature and very prevalent for privacy-preserving protocols. To cope with this kind of attack, we propose a novel and practical protocol that uses Public key encryption with an equality test (PKEET) to search over the encrypted identities without leaking any information, and eventually eliminate the Sybil attack. The proposed approach improves security and at the same time maintains privacy in VANET. Our performance analysis indicates that the proposed protocol outperforms state-of-the-art protocols: The proposed beacon generation time is constant compared to a linear increase in existing protocols, with beacon verification shown to be faster by 7.908%. Our communicational analysis shows that the proposed protocol with a beacon size of 322 bytes has the least communicational overhead compared to other state-of-the-art protocols.