Head Of Unit Research Articles

Cryptanalysis of Start Code-Based Encryption Method for HEVC

We propose a cryptanalysis for MPEG high efficiency video coding bitstream encryption based on the start code. Today, most digital video data are transmitted over an open Internet network in an encrypted state for security and privacy. In general, video services must guarantee real-time communications; therefore, it is necessary to reduce the computational complexity required to encrypt video data. Consequently, many selective encryption algorithms that selectively encrypt a highly sensitive part of the entire video data have been studied. Recently, we proposed a selective encryption algorithm based on the start code for high efficiency video coding, which dramatically reduces the computational complexity of encryption. In this paper, we studied the cryptanalysis of the encryption algorithm based on the start code and found a security vulnerability for a ciphertext-only attack. The proposed method presents a method to restore the encrypted first byte of the network abstraction layer unit header by analyzing the unencrypted high efficiency video coding bitstream. The first byte of the network abstraction layer unit header can be restored using the unencrypted parts, such as the order, syntax element, and length of the network abstraction layer unit. The experimental results demonstrated the security vulnerability by breaking the start code based encryption algorithm that is difficult to recover using the brute-force attack with only one to six recovery attempts using the proposed ciphertext-only attack.

Psychiatric Morbidity and Emotional Exhaustion Among Hospital Physicians and Nurses: Association With Perceived Job-Related Factors

ABSTRACT The objective of this study was to evaluate psychiatric morbidity and emotional exhaustion among physicians and nurses of a general hospital in central Italy, examining the association with perceived job-related factors. Anonymous questionnaires were distributed to all 323 hospital physicians and 609 nurses of a nonprofit health organization in Rome, Italy. Standardized instruments were used to evaluate psychiatric morbidity (General Health Questionnaire), burnout (Maslach Burnout Inventory), and perceived job-related factors. Logistic regression was used to examine the association between job-related factors, psychiatric morbidity, and burnout, controlling for demographic factors. Questionnaires were returned by 155 physicians and 216 nurses (overall response rate 40%). Estimated prevalence of psychiatric morbidity was 25% among physicians and 36.9% among nurses. Burnout on the emotional exhaustion scale affected 38.7% of physicians and 46.4% of nurses. Personnel with emotional exhaustion was at higher risk of psychiatric morbidity (p < .001). The likelihood of psychiatric morbidity among physicians was increased by perceived insufficient recognition of personal commitments by the unit's head (odds ratio [OR] = 4.21; 95% confidence interval [CI] 1.2–15.1; p = .027), insufficient managerial ability of the unit's head (OR = 3.45; 95% CI 1.2–10.1; p = .023), and unsatisfactory communication (OR = 5.30; 95% CI 1.6–17.6; p = .006). Among nurses, psychiatric morbidity was associated with insufficient ability of the unit's head to solve conflicts, insufficient decisional power in relation to responsibilities, insufficient economic rewards and career possibilities, and working in surgery. Similar job-related factors were associated also with emotional exhaustion. Psychiatric morbidity and emotional exhaustion were relatively high, particularly among nurses. Specific job-related factors were associated with psychiatric morbidity and burnout. Improving these aspects is important for the well-being of hospital staff and the quality of patient care.

Engaging medical staff in clinical governance: introducing new technologies and clinical practice into public hospitals

To enhance patient care, medical staff at major tertiary teaching hospitals are encouraged to innovate through introducing new technologies and clinical practices. However, such introduction must be safe, efficient, effective and appropriate for patients and the organisation, and actively lead by engage medical staff. This study outlines the development, implementation and evaluation of a framework for introducing new technologies and clinical practice to a major tertiary health service. Evaluation includes survey of medical Heads of Units (HOUs) for framework's effectiveness, and comparison of level of medical staff engagement against a best-practice model. Over 2-year period: 19 applications, 7 approved. Successful external funding of $1.993 million achieved. Survey of HOUs in June 2009: response rate 59% (25 of 42 HOUs), with 11 of 25 respondents utilised the committee. Of those 14 of 25 who had not utilised the committee, low awareness of the committee's existence (2 respondents). Most elements of the best-practice model for engaging medical staff were achieved. Recommendations include improvements to committee process and raising profile with medical staff. This study demonstrates an effective and successful clinical governance process for introducing new technologies and clinical practice into a major tertiary teaching hospital, supported by moderate levels of medical staff engagement.

A Practical RTP Packetization Scheme for SVC Video Transport over IP Networks

Scalable video coding (SVC) has been standardized as an extension of the H.264/AVC standard. This paper proposes a practical real-time transport protocol (RTP) packetization scheme to transport SVC video over IP networks. In combined scalability of SVC, a coded picture of a base or scalable enhancement layer is produced as one or more video layers consisting of network abstraction layer (NAL) units. The SVC NAL unit header contains a (DID, TID, QID) field to identify the association of each SVC NAL unit with its scalable enhancement layer without parsing the payload part of the SVC NAL unit. In this paper, we utilize the (DID, TID, QID) information to derive hierarchical spatio-temporal relationship of the SVC NAL units. Based on the derivation using the (DID, TID, QID) field, we propose a practical RTP packetization scheme for generating single RTP sessions in unicast and multicast transport of SVC video. The experimental results indicate that the proposed packetization scheme can be efficiently applied to transport SVC video over IP networks with little induced delay, jitter, and computational load.

Impact of administrative reform of the European Commission: results from a survey of heads of unit in policy-making directorates

The Kinnock reform has changed the European Commission. This article discusses the link between reform effects and policy output. A survey of more than 100 heads of unit (HoU) of policy-making Directorates-General serves as the empirical basis. It is concluded that the recent reform of the Commission does indeed comprehensively redefine the role of the HoU. Their resource base to focus on policy drafting has been hugely reduced. Negative consequences for the organization’s potential to deliver policy draft of high quality are therefore very likely. Points for practitioners This article deals with the following areas: • Middle management as organizational backbone • The perils of decentralizing management functions • The impact of administrative reform on policy output.

System and Transport Interface of SVC

Scalable video coding (SVC) and transmission has been a research topic for many years. Among other objectives, it aims to support different receiving devices, perhaps connected through a heterogeneous network structure, using a single bit stream. Earlier attempts of standardized scalable video coding, for example in MPEG-2, H.263, or MPEG-4 Visual, have not been commercially successful. Nevertheless, the Joint Video Team has recently focused on the development of the scalable video extensions of H.264/AVC, known as SVC. Some of the key problems of older scalable compression techniques have been solved in SVC and, at the same time, new and compelling use cases for SVC have been identified. While it is certainly important to develop coding tools targeted at high coding efficiency, the design of the features of the interface between the core coding technologies and the system and transport are also of vital importance for the success of SVC. Only through this interface, and novel mechanisms defined therein, applications can take advantage of the scalability features of the coded video signal. This paper provides an overview of the system interface features defined in the SVC specification. We discuss, amongst other features, bit stream structure, extended network abstraction layer (NAL) unit header, and supplemental enhancement information (SEI) messages related to scalability information.

RTP payload format for H.264/SVC scalable video coding

The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC. Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL) and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, including the design criteria, use cases, signaling and payload structure.

HIV in South Africa

More than 1 in 40 young adults in South Africa were estimated to be infected with HIV through the end of 1992. The rate of infection has slowed so that the current doubling time is 16 months; 400 people are nonetheless newly infected daily. HIV and AIDS were first noted among gay White Men in the Cape of South Africa. Education and support from within the gay community, however, prompted the rapid and substantial decrease in the incidence of infection. The 1st evidence of infection among Black heterosexuals was then noted in 1987. It is mainly young adults who are infected, with women affected earlier than and at least as often as men. The arrival of HIV to South Africa and its expected pattern of transmission should have been no surprise to country health policymakers and administrators. Sexually transmitted diseases (STD) facilitate the spread of HIV infection and tuberculosis (TB) fosters the development of AIDS once people are infected with HIV. An estimated 3 million cases of STD present annually in South Africa and almost half of the adult population is infected with quiescent TB. The failure to learn from experiences with HIV in some central and eastern Africa countries simply highlights the extent of poor public health in South Africa. South Africa has the infrastructure and health funding needed to check AIDS, but failed to take action. The central health ministry did not respond to the epidemic until 1990 with the establishment of an AIDS unit, secondary school AIDS prevention programs and packages in 8 languages, a neutral national information campaign, workshops to increase awareness, and funding to organizations targeting hard-to-reach groups. The AIDS unit was soon merged into a health promotion section and the unit's head fired, with all the prevention initiatives terminated except the continued availability of pamphlets in only English and Afrikaans. An official complaint has been made to no avail against the health department official who closed the AIDS campaign. Meanwhile, the government contends that it holds no responsibility for educating its population in the prevention of AIDS. These recent actions suggest that the government is committing genocide by allowing excess mortality from AIDS to decimate Black heterosexuals during the impending period of interim rule and political transition. These observations and conclusions are based in part on the author's experience as medical advisor to South Africa's AIDS unit in 1991/92.