Efficient Error Control for Scalable Media Transmission over 3G Broadcast Networks

Abstract. Broadcast and mobile phone technologies have now combined to provide wireless multimedia services. 3GPP2 has introduced the Broadcast and Multicast Services (BCMCS) architecture in a 3G wireless network. BCMCS are capable of supplying multimedia content, which requires successive frames to arrive within a specific time interval. We analyze the execution time of Reed-Solomon decoding, which is the MAC-layer forward error correction scheme used in cdma2000 1xEV-DO BCMCS, under different air channel conditions. The results show that the time constraints of MPEG-4 cannot be guaranteed by Reed-Solomon decoding when the packet loss rate (PLR) is high, due to its long computation time on current hardware. To alleviate this problem, we propose three error control schemes. Our static scheme bypasses Reed-Solomon decoding at the mobile node to satisfy the MPEG-4 time constraint when the PLR exceeds a given boundary. Our second, dynamic scheme corrects errors in a best-effort manner within the time constraint, instead of giving up altogether when the PLR is high. The third, video-aware dynamic scheme fixes errors in a similar way to the dynamic scheme, but in a priority-driven manner which improves the quality of the final video. Extensive simulation results show the effectiveness of our schemes compared to the original FEC scheme

Effects of initial public offerings on economic performance of small and medium-sized enterprises

This study investigates the effects of the initial public offerings (I.P.O.s) of small and medium-sized enterprises (S.M.E.s) and their efforts to cooperate with large conglomerates on S.M.E.s’economic performance and job creation. This study conducted a series of analyses of variance with a 22 between-subject design (I.P.O.s and cooperation with large conglomerates) and multiple regression analyses for credit ratings using 4419 and 3919 samples, respectively, of S.M.E.s from the Korea Innovation Survey. The results showed that I.P.O.s and cooperation with large conglomerates are positively associated with S.M.E.s’job creation as well as multiple economic outcomes. Moreover, several scholars have argued that more accurate credit rating criteria should be proposed to evaluate the potential values of S.M.E.s because the current criteria mainly focus on their short-term financial and economic performance. Based on the results of the multiple regression analyses, this study found that I.P.O.s have a negative effect on S.M.E.s’credit ratings, whereas cooperation with large conglomerates and job creation have no effect and the growth rates of net income and current assets have a positive effec

Enhanced pqsigRM: Code-Based Digital Signature Scheme with Short Signature and Fast Verification for Post-Quantum Cryptography

We present a novel code-based digital signature scheme, called Enhanced pqsigRM for post-quantum cryptography (PQC). This scheme is based on modified Reed–Muller (RM) codes, which modified RM codes with several security problems. Enhanced pqsigRM is a strengthened version of pqsigRM, which was submitted to NIST PQC standardization in round 1. The proposed scheme has the advantage of short signature size, fast verification cycles. For 128 bits of classical security, the signature size of the proposed scheme is 1032 bytes, which corresponds to 0.42 times that of Crystals-Dilithium, and the number of median verification cycles is 235,656, which is smaller than that of Crystals-Dilithium. Also, we use public codes, called modified RM codes, that are more difficult to distinguish from random codes. We use (U,U + V )-codes with high-dimensional hull to make these. Using modified RM codes, the proposed signature scheme resists various known attacks on RM-code-based cryptography. The proposed decoder samples from coset elements with small Hamming weight for any given syndrome and efficiently finds such elements

Understanding the Emergence and Social Acceptance of Electric Vehicles as Next-Generation Models for the Automobile Industry

This study explores potential factors of drivers’ intentions to use electric vehicles and proposes an integrated adoption model. Results of a structural equation modeling analysis with 988 samples indicate that drivers’ intentions are predicted by one negative factor (cost) and three positive ones (satisfaction, usefulness, and attitude). In addition, the total standardized effects of potential factors on the intention are computed. The current study also validates the original technology acceptance model. Based on the results of the current study, practical and academic implications with potential limitations are examined and presented

Family Members of Cancer Patients in Korea Are at an Increased Risk of Medically Diagnosed Depression

Objectives Family members are often cancer patients’ primary source of social and emotional support and make a major contribution to how well patients manage their illness. We compared the prevalence of depression in the family members of cancer patients and the general population. Methods This study used the data from the fourth, fifth, and sixth rounds of the Korea National Health and Nutrition Examination Survey. The variable of interest was the presence of a cohabitating cancer patient in the family and the dependent variable was the presence of diagnosed depression. Results The odds of having medically diagnosed depression in those with a cohabitating cancer patient in the family were significantly higher than among those who did not have cancer patients in their families (odds ratio [OR], 1.56; 95% confidence interval [CI], 1.12 to 2.17; p=0.009). The OR for females was 1.59, and this increase was statistically significant (95% CI, 1.09 to 2.31; p=0.02). Conclusions We need to invest more effort into diagnosing and managing depression in the family members of cancer patients. This will have an impact both on their quality of life and on the well-being of patients, as supporters and caregivers play an instrumental role in helping patients manage their illness

Cognitive Radio-Based Vehicular Ad Hoc and Sensor Networks

Current advancements in vehicular networking lead to amplifying the issue of spectrum scarcity. Cognitive radio (CR) has emerged as the key technology that enables flexible, efficient, and reliable spectrum exploiting by unlicensed networks to use licensed spectrum bands in an opportunistic manner to alleviate the spectrum scarcity issue. We have already proposed vehicular ad hoc and sensor networks (VASNET) as a new networking paradigm for vehicular communication by utilizing wireless sensor nodes in two mobile and stationary modes. The nodes are employed to sense vehicles' activity, for example, car crashes. Like other unlicensed networks, VASNET is supposed to operate over unlicensed spectrum bands. However, due to emergency nature of accident alarms in VASNET that must be received in minimum period of time and avoiding packet loss, in this paper we investigate CR-based VASNET, named as CR-VASNET. Various challenges and issues are discussed in details. In order to save stationary nodes' power and enlarge the network lifetime, an optimization technique for relay node selection is proposed. Furthermore, for primary users (PU) protection, an energy detection-based scheme is suggested to calculate the probability of PU arrival. Our theoretical discussions and simulation results proved the efficient functionality of the proposed CR-VASNET as a promising vehicular networking paradigm