A New Key Management Scheme for a User Hierarchy based on a Hybrid Cryptosystem

Vanga Odelu,Ashok Kumar Das,Adrijit Goswami 한국산학기술학회 2013 SmartCR Vol.3 No.1

In general applications’, changing a secret key of a user provides maximum security for the system. Thus, a user in an organization needs to change his/her secret key from time to time to achieve maximum security. Changing the secret key of a user in an organization is more frequent than a user simply joining or leaving the organization. Dynamic properties such as changing the key of a user in a hierarchy affects the performance of an access control scheme more than other dynamic properties such as adding or deleting a security class to the hierarchy. As a result, we need to design an effective access control scheme to change keys of users in the hierarchy. However, most schemes proposed in the literature do not provide an efficient solution. In this paper, we propose a new key management mechanism for hierarchical access control that provides an effective solution. Moreover, our scheme efficiently supports other dynamic properties, such as adding or deleting a security class. Further, we proposed an efficient procedure for key generation and key derivation for access control. Through formal and informal security analysis, we prove our scheme tolerates various known attacks in access control. We show that our scheme has better performance compared to other related schemes. As a result, higher security along with efficient access control properties makes our scheme more suitable for practical applications.

Synthesis and Anti Bacterial and Anti-ulcer Evaluation of New S-mannich Bases of 4,6-diaryl-3,4-dihydropyrimidin-2(1H)-thiones

Kodhati, Venkateshwarlu,Vanga, Malla Reddy,Yellu, Narsimha Reddy Korean Chemical Society 2013 대한화학회지 Vol.57 No.2

The synthesis of title compounds were accomplished by synthetic sequence shown in Scheme 1. Chalcones on cyclocondensation with thiourea in ethanol and potassium hydroxide under reflux yielded the respective dihydropyramidin-2(1H)-thiones. Each of the dihydropyrimidin thiones was, then subjected to the Mannich condensation in alkaline medium using three different secondary amines, viz., dimethylamine, diethylamine and morpholine to obtain a new series of S-Mannich bases. All the synthesised compounds ($C_1-C_{15}$) were evaluated for their antiulcer and antibacterial activities. Compounds $C_4$, $C_5$, $C_6$, $C_{14}$ and $C_{15}$ exhibited relatively more potent antiulcer activity but not comparable to the standard; Omeprazole, while $C_1$, $C_2$, $C_3$ and $C_{13}$ were moderate in activity at 100 mg/kg p.o. All the compounds ($C_1-C_{15}$) showed mild to moderate activity against both Gram-positive (S.aureus, L.delbrueckii) and Gram-negative (P.vulgaris, E.coli) bacteria. Amongst the compounds tested, only $C_6$, $C_9$, $C_{12}$ and $C_{15}$ were found to be potent.

Design of Secure User Authenticated Key Management Protocol for Generic IoT Networks

Wazid, Mohammad,Das, Ashok Kumar,Odelu, Vanga,Kumar, Neeraj,Conti, Mauro,Jo, Minho IEEE 2018 IEEE Internet of things journal Vol.5 No.1

<P>In recent years, the research in generic Internet of Things (IoT) attracts a lot of practical applications including smart home, smart city, smart grid, industrial Internet, connected healthcare, smart retail, smart supply chain and smart farming. The hierarchical IoT network (HIoTN) is a special kind of the generic IoT network, which is composed of the different nodes, such as the gateway node, cluster head nodes, and sensing nodes organized in a hierarchy. In HIoTN, there is a need, where a user can directly access the real-time data from the sensing nodes for a particular application in generic IoT networking environment. This paper emphasizes on the design of a new secure lightweight three-factor remote user authentication scheme for HIoTNs, called the user authenticated key management protocol (UAKMP). The three factors used in UAKMP are the user smart card, password, and personal biometrics. The security of the scheme is thoroughly analyzed under the formal security in the widely accepted real-or-random model, the informal security as well as the formal security verification using the widely accepted automated validation of Internet security protocols and applications tool. UAKMP offers several functionality features including offline sensing node registration, freely password and biometric update facility, user anonymity, and sensing node anonymity compared to other related existing schemes. In addition, UAKMP is also comparable in computation and communication costs as compared to other existing schemes.</P>

Effusion hole의 compound angle 변화에 따른 이중벽 냉각의 열전달 특성 변화에 관한 수치해석적 연구

권화빈(Hwabhin Kwon),Sneha Reddy Vanga,Phil Ligrani,박희성(Heesung Park) 대한기계학회 2020 대한기계학회 춘추학술대회 Vol.2020 No.12

A User Anonymous Mutual Authentication Protocol

( Saru Kumari ),( Xiong Li ),( Fan Wu ),( Ashok Kumar Das ),( Vanga Odelu ),( Muhammad Khurram Khan ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.9

Widespread use of wireless networks has drawn attention to ascertain confidential communication and proper authentication of an entity before granting access to services over insecure channels. Recently, Truong et al. proposed a modified dynamic ID-based authentication scheme which they claimed to resist smart-card-theft attack. Nevertheless, we find that their scheme is prone to smart-card-theft attack contrary to the author`s claim. Besides, anyone can impersonate the user as well as service provider server and can breach the confidentiality of communication by merely eavesdropping the login request and server`s reply message from the network. We also notice that the scheme does not impart user anonymity and forward secrecy. Therefore, we present another authentication scheme keeping apart the threats encountered in the design of Truong et al.`s scheme. We also prove the security of the proposed scheme with the help of widespread BAN (Burrows, Abadi and Needham) Logic.

Cone-beam computed tomography analysis of accessory maxillary ostium and Haller cells: Prevalence and clinical significance

Ali, Ibrahim K.,Sansare, Kaustubh,Karjodkar, Freny R.,Vanga, Kavita,Salve, Prashant,Pawar, Ajinkya M. Korean Academy of Oral and Maxillofacial Radiology 2017 Imaging Science in Dentistry Vol.47 No.1

Purpose: This study aimed to evaluate the prevalence of Haller cells and accessory maxillary ostium (AMO) in cone-beam computed tomography (CBCT) images, and to analyze the relationships among Haller cells, AMO, and maxillary sinusitis. Materials and Methods: Volumetric CBCT scans from 201 patients were retrieved from our institution's Digital Imaging and Communications in Medicine archive folder. Two observers evaluated the presence of Haller cells, AMO, and maxillary sinusitis in the CBCT scans. Results: AMO was observed in 114 patients, of whom 27 (23.7%) had AMO exclusively on the right side, 26 (22.8%) only on the left side, and 61 (53.5%) bilaterally. Haller cells were identified in 73 (36.3%) patients. In 24 (32.9%) they were present exclusively on the right side, in 17 (23.3%) they were only present on the left side, and in 32 (43.8%) they were located bilaterally. Of the 73 (36.3%) patients with Haller cells, maxillary sinusitis was also present in 50 (68.5%). On using chi-square test, a significant association was observed between AMO and maxillary sinusitis in the presence of Haller cells. Conclusion: Our results showed AMO and Haller cells to be associated with maxillary sinusitis. This study provides evidence for the usefulness of CBCT in imaging the bony anatomy of the sinonasal complex with significantly higher precision and a smaller radiation dose.

연소기 냉각을 위한 이중벽 냉각 구조에서 effusion hole의 방향각 변화에 따른 냉각 성능 및 유동 특성에 관한 수치해석적 연구

권화빈(Hwabhin Kwon),Phillip M. Ligrani,Sneha R. Vanga,박희성(Heesung Park) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.11

Two double-wall cooling structures are presented, and the angle of the effusion hole direction is considered to be 0 ° and 30 °, respectively. Numerically analyze the flow characteristics of main flow, cross flow, effusion hole, and impingement hole. Changing the orientation angle from 0 ° to 30 °, the area-averaged film cooling efficient and hot-side surface heat transfer coefficient is improved. The change in direction angle suppresses the counter rotating vortex that causes jet-lift. Heat transfer is increased by the wide effective area of the horseshoe vortex. Also, as the orientation angle is changed from 0 ° to 30 °, the area average Nusselt number of the cold side improved.

Cone-beam computed tomography analysis of accessory maxillary ostium and Haller cells: Prevalence and clinical significance

Ibrahim K. Ali,Kaustubh Sansare,Freny R Karjodkar,Kavita Vanga,Prashant Salve,Ajinkya M. Pawar 대한영상치의학회 2017 Imaging Science in Dentistry Vol.47 No.1

Purpose: This study aimed to evaluate the prevalence of Haller cells and accessory maxillary ostium (AMO) in cone-beam computed tomography (CBCT) images, and to analyze the relationships among Haller cells, AMO, and maxillary sinusitis. Materials and Methods: Volumetric CBCT scans from 201 patients were retrieved from our institution’s Digital Imaging and Communications in Medicine archive folder. Two observers evaluated the presence of Haller cells, AMO, and maxillary sinusitis in the CBCT scans. Results: AMO was observed in 114 patients, of whom 27 (23.7%) had AMO exclusively on the right side, 26 (22.8%) only on the left side, and 61 (53.5%) bilaterally. Haller cells were identified in 73 (36.3%) patients. In 24 (32.9%) they were present exclusively on the right side, in 17 (23.3%) they were only present on the left side, and in 32 (43.8%) they were located bilaterally. Of the 73 (36.3%) patients with Haller cells, maxillary sinusitis was also present in 50 (68.5%). On using chi-square test, a significant association was observed between AMO and maxillary sinusitis in the presence of Haller cells. Conclusion: Our results showed AMO and Haller cells to be associated with maxillary sinusitis. This study provides evidence for the usefulness of CBCT in imaging the bony anatomy of the sinonasal complex with significantly higher precision and a smaller radiation dose.