Journal articles on the topic 'Simplified composite right'

In this paper, a novel simplified composite right/left handed (SCRLH) transmission line (TL) structure is proposed.The dispersion and impedance characteristics of the novel structure are first analysed based on Bloch-Floquet theory, which shows that the attenuation constant keeps zero with a relatively smooth characteristic impedance distribution within the passband and that the characteristic impedance is purely imaginary with the inhibition of the electromagetic wave propagation outside the passband.

A novel ultra-wideband(UWB) bandpass filter with dual notch-bands and wide stop-band is proposed. The designed UWB BPF is cascading a coupled simplified composite right-left-handed (SCRLH) resonator and a ring slot resonator (RSR). The SCRLH resonator creates two different notch-bands. And the RSR unit suppresses the higher-order harmonics at the upper stop-band. The UWB BPF demonstrated good insertion/return losses and out-of-band rejections in simulation.

This paper addresses the issues of low bandwidth, gain, and efficiency of miniaturized microwave antennas by proposing a novel wideband dual-frequency coplanar waveguide antenna design based on a simplified composite right/left-handed (SCRLH) transmission line structure with Hilbert curve loading. The multifrequency characteristics of the SCRLH transmission line structure are evaluated theoretically, and the antenna parameters promoting bandwidth broadening under zeroth-order resonance (ZOR) and first-order resonance (FOR) mode operation are evaluated. The bandwidth broadening in the ZOR and FOR modes is accordingly revealed to be independent of the antenna length, and the structure therefore facilitates wideband operation under miniaturization. Finally, the dual-frequency ZOR and FOR mode antenna design with center frequencies of f0 = 1.865 GHz and f1 = 2.835 GHz is validated via simulation, and the performance of a compact prototype antenna is evaluated experimentally. The −10 dB return loss bandwidths at f0 and f1 are 187 MHz (from 1.773 GHz to 1.96 GHz) and 368 MHz (from 3.002 GHz to 3.37 GHz), and the corresponding relative bandwidths are 10.1% and 11.5%, respectively. The experimentally measured peak gains and radiation efficiencies at f0 are 1.54 dB and 81.3%, respectively, and those at f1 are 1.71 dB and 74.2%, respectively.

The design and analysis of meta-material inspired loaded monopole antenna for multiband operation are reported. The proposed antenna consists of multi resonators inspired from half mode composite right/left handed cells, which has a simple structure, compact size, and provides multiband functionalities. As a proof of concept, a triple band antenna covering all possible WiMAX operating bands, has been designed, fabricated, and characterized. The hosting monopole patch itself generates resonance for 3.3–3.8 GHz band, whereas the loaded metamaterial cells add extra resonance frequencies. The loading of two resonator cells introduces two extra resonances for 2.5–2.7 GHz and 5.3–5.9 GHz bands, respectively. The antenna's operating principle and design procedures with the aid of electromagnetic full wave simulation and experimental measurements are presented. The antenna has good omnidirectional patterns at all three bands. The monopole patch size is 13.5 × 6.5 mm2and the whole antenna size (including the feed line) is 35 × 32 mm2. Compared with conventional single band microstrip patch radiator, the radiator size of this antenna is only 8.5% at 2.5 GHz, 17% at 3.5 GHz, and 37% at 5.5 GHz.

In this paper, a new steel-wood composite column with an H-shaped section was proposed. In order to form an H-shaped cross section, a larch board is fixed on the outer surface of the left and right edges of a hot-rolled H-beam by using physical connection. When the eccentricity is the same, eccentric compression tests were carried out on two types of columns by changing the thickness of the larch board, cross-sectional area of the hot-rolled H-beam, and slenderness ratio in composite columns. Therefore, type A is joined by structural glue only with the larch board and hot-rolled H-beam, and type B is joined by both structural glue and bolts. With the variation of strain and deflection, failure process and failure modes of the hot-rolled H-beam and larch from composite columns under various loads were observed, and the ultimate bearing capacity and stability of composite columns were studied. The test results showed that the overall working performance of the hot-rolled H-beam and larch board was good, and the stability of the hot-rolled H-beam column could be effectively improved. With the increase of wood thickness, cross-sectional area of the hot-rolled H-beam, slenderness ratio of composite columns, and the bearing capacity of the specimens were increased. Moreover, a simplified formula was proposed by the superposition principle. The theoretical analysis accorded with the experimental results, thus providing a reference basis for further study and application of similar steel-wood composite columns.

The prognosis of multidetector computed tomography (MDCT) assessed right ventricular dilatation (RVD) is unclear in patients with pulmonary embolism (PE) and a simplified Pulmonary Embolism Severity Index (sPESI) of 0. We investigated in these patients whether MDCT-assessed RVD, defined by a right to left ventricular ratio (RV/LV) ≥0.9 or ≥1.0, is associated with worse outcomes.We combined data from three prospective cohorts of patients with PE. The main study outcome was the composite of 30-day all-cause mortality, haemodynamic collapse or recurrent PE in patients with sPESI of 0.Among 779 patients with a sPESI 0, 420 (54%) and 299 (38%) had a RV/LV ≥0.9 and ≥1.0 respectively. No difference in primary outcome was observed, 0.95% (95% CI 0.31–2.59) versus 0.56% (95% CI 0.10–2.22; p=0.692) and 1.34% (95% CI 0.43–3.62) versus 0.42% (95% CI 0.07–1.67; p=0.211) with RV/LV ≥0.9 and ≥1.0 respectively. Increasing the RV/LV threshold to ≥1.1, the outcome occurred more often in patients with RVD (2.12%, 95% CI 0.68–5.68 versus 0.34%, 95% CI 0.06–1.36; p=0.033).MDCT RV/LV ratio of ≥0.9 and ≥1.0 in sPESI 0 patients is frequent but not associated with a worse prognosis but higher cut-off values might be associated with worse outcome in these patients.

A nonlinear dynamic analysis of the cutting process of a nonextensible composite cutting bar is presented. The cutting bar is simplified as a cantilever with plane bending. The nonlinearity is mainly originated from the nonextensible assumption, and the material of cutting bar is assumed to be viscoelastic composite, which is described by the Kelvin–Voigt equation. The motion equation of nonlinear chatter of the cutting system is derived based on the Hamilton principle. The partial differential equation of motion is discretized using the Galerkin method to obtain a 1-dof nonlinear ordinary differential equation in a generalized coordinate system. The steady forced response of the cutting system under periodically varying cutting force is approximately solved by the multiscale method. Meanwhile, the effects of parameters such as the geometry of the cutting bar (including length and diameter), damping, the cutting coefficient, the cutting depth, the number of the cutting teeth, the amplitude of the cutting force, and the ply angle on nonlinear lobes and primary resonance curves during the cutting process are investigated using numerical calculations. The results demonstrate that the critical cutting depth is inversely proportional to the aspect ratio of the cutting bar and the cutting force coefficient. Meanwhile, the chatter stability in the milling process can be significantly enhanced by increasing the structural damping. The peak of the primary resonance curve is bent toward the right side. Due to the cubic nonlinearity in the cutting system, primary resonance curves show the characteristics of typical Duffing’s vibrator with hard spring, and jump and multivalue regions appear.

BackgroundAcute pulmonary embolism (PE) has a wide spectrum of outcomes, but the best method to risk-stratify normotensive patients for adverse outcomes remains unclear.MethodsA multicentre retrospective cohort study of acute PE patients admitted from emergency departments in Calgary, Canada, between 2012 and 2017 was used to develop a refined acute PE risk score. The composite primary outcome of in-hospital PE-related death or haemodynamic decompensation. The model was internally validated using bootstrapping and the prognostic value of the derived risk score was compared to the Bova score.ResultsOf 2067 patients with normotensive acute PE, the primary outcome (haemodynamic decompensation or PE-related death) occurred in 32 (1.5%) patients. In simplified Pulmonary Embolism Severity Index high-risk patients (n=1498, 78%), a multivariable model used to predict the primary outcome retained computed tomography (CT) right–left ventricular diameter ratio ≥1.5, systolic blood pressure 90–100 mmHg, central pulmonary artery clot and heart rate ≥100 beats·min−1 with a C-statistic of 0.89 (95% CI 0.82–0.93). Three risk groups were derived using a weighted score (score, prevalence, primary outcome event rate): group 1 (0–3, 73.8%, 0.34%), group 2 (4–6, 17.6%, 5.8%), group 3 (7–9, 8.7%, 12.8%) with a C-statistic 0.85 (95% CI 0.78–0.91). In comparison the prevalence (primary outcome) by Bova risk stages (n=1179) were stage I 49.8% (0.2%); stage II 31.9% (2.7%); and stage III 18.4% (7.8%) with a C-statistic 0.80 (95% CI 0.74–0.86).ConclusionsA simple four-variable risk score using clinical data immediately available after CT diagnosis of acute PE predicts in-hospital adverse outcomes. External validation of the Calgary Acute Pulmonary Embolism score is required.

Abstract Background: We recently presented that the humanized anti-complement C1s monoclonal antibody, TNT009, rapidly stoppedhemolysisand correctedanemiain patients with severe CAD in an ongoing Phase 1b clinical trial. After completion of washout from protocol treatment, these patients suffered relapse of CAD with a drop inhemoglobinto pre-dose levels. We now report on the clinical experience of their extended re-treatment under the Named Patient provision of the Austrian Drug Act, which provided the occasion: 1) to explore lower dose regimens and alternative dosing schedules; 2) to try to recapitulate the initial success of complete remission under protocol treatment; 3) to test the durability of response with a longer term maintenance treatment with TNT009. Methods: In order to test a lower dose regimen of TNT009, the Phase 1b trial dosing of 60 mg/kg IV once weekly for both loading and maintenance was reduced to 45 mg/kg IV once weekly (4x) followed by maintenance with 45 mg/kg every other week. A simplified dosing regimen was then tried, using a single priming dose of 60 mg/kg on Day 0 followed by 60 mg/kg every other week (biweekly) thereafter beginning on Day 7. This TNT009 biweekly maintenance with 60 mg/kg was continued indefinitely to test the durability of the effect, to monitor for safety, and to serially assess their hematologic response to TNT009. Results:All infusions were well tolerated without premedication and without relevant adverse effects. TNT009 re-exposure immediately decreased CH50 activity and increased complement C4 levels, confirming the rapid onset ofpharmacodynamiceffect. The concordant and sustained effect of TNT009 on hematologic parameters related tohemolysisandanemiasis illustrated in the composite Figure 1 for the first patient treated, C1001. This patient has undergone three treatment episodes with TNT009: weekly dosing at 60 mg/kg under the Phase 1b protocol (left); weekly → biweekly 45 mg/kg (center); 60 mg/kg on Day 0 and biweekly thereafter starting on Day 7 (right). Note that the CH50 serves as apharmacodynamicmarker for the effective inhibition of the classical complement pathway by TNT009. Each new episode of treatment with TNT009 induced remission ofhemolyticanemia, and relapse occurred following washout (60 mg/kg weekly x 4) orpharmacodynamicbreakthrough (45 mg/kg maintenance regimen). Although it appears that the reduced dose maintenance regimen of 45 mg/kg biweekly does not suffice to maintain full C1s inhibition, there is no evidence oftachyphylaxisas restoration of full dose treatment at 60 mg/kg biweekly was able to restore remission again. A similar pattern of results was observed in the other patients offered Named Patient treatment with TNT009, but with two instructive exceptions. Patient C1004 had unsuspected erythropoietin deficiency and did not achieve complete normalization ofhemoglobinuntil concomitant treatment with erythropoietin was begun. Patient C1003 did not have CAD but Cold Agglutinin Syndrome (CAS) secondary to an extensivelymphoplasmacyticlymphoma (LPL). Initially she was treated with TNT009 monotherapy and did not respond. TNT009 was then stopped and her LPL was treated withibrutinib, resulting in a gradual amelioration of heranemiauntil anintercurrentinfection triggered relapse of herhemolyticanemia. At that time re-treatment with TNT009 (whileibrutinibwas continued) quickly normalized her hematologic parameters. Eventually TNT009 was able to increasehemoglobinlevels to >12 g/dLin all 5 of 5 treated patients. Conclusion:TNT009 was previously shown to induce rapid correction ofhemolyticanemiain severe CAD patients in a Phase 1b trial. It has now been shown that subsequent washout of TNT009 leads to relapse in all patients, and that re-induction of remission by TNT009 is possible in all. Long-term maintenance of remission can be achieved by dosing TNT009 at 60 mg/kg biweekly, the dose regimen to be tested in larger-scale clinical trials of CAD. Figure Figure. Disclosures Gilbert: Truenorth Therapeutics, Inc.: Employment, Equity Ownership. Panicker:Truenorth Therapeutics, Inc.: Employment. Parry:Truenorth Therapeutics, Inc.: Employment, Equity Ownership. Jaeger:Janssen: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses.

The article proposes analyze of the balalaika art and technical potential. The complex of texture- and register and timbreand phonic methods of suites performing, which represent the Ukrainian interpretation tradition of the genre, is determined. Instrumentalism principles and impacts in balalaika performance in the composer’s works of the twentieth century are revealed. Texture features of the works for balalaika suite genre are considered, the characteristics on the genesis stage of balalaika are marked: simplifi ed chord texture with narrow range, predominant two and three-voice texture in cantilena, minute passage technique with a small set of traditional rotations. Texture types of musical thematic presentment and the level of virtuosity of the stringed instruments in the sound formation are determined. The object of research is the professional performance on the balalaika. The subject of research is performing on balalaikas of Kharkiv as a component of Ukrainian musical art. In terms of instrumentalism as a type of thinking the method of sound production on the balalaika, dependent by the direct contact of the right hand fi ngers with a string, which is basic, creating countless bar, dynamic and timbral combinations, is revealed. In for balalaika M. Stetsun “With Balalaika in Spain” analyzed genre prototypes of the, that the impacts of the new romantic suite, characterized by a compound of stable (required) and free-variable cycle parts, based on the experience of the other genre forms of music-making, are immediately traced. Attention is paid to the unplugged (where violin takes the leading position), dynamic (where piano owns leading positions) and texture capabilities. Balalaika qualities are analyzed: limitation of natural acoustic properties requires texture mobility and frequent use of the tremolo; dynamic capabilities are also limited, as the result the “step” dynamics development is applied; texture possibilities are largely constrained by the range and technology. The principle of genre and stylistic synthesis, in which song and dance origins of national folklore and shaping structural logic borrowed from the experience of the Ukraine tradition are organically combined, is formulated. Multiple ties with folk traditions, which include: reliance on folklore themes and quotes; development techniques of the song thematic (inner thematic variation, imitation roll, undervoice polyphony, hidden two-voice texture); metro-rhythmic formula, coming from the dance genre; irregular accent, intended to the saturation of images with internal dynamics are revealed in the Concerto for balalaika and orchestra by A. Gaidenko. The use of styling techniques of playing folk music instruments in the balalaika party, which was used for the creation of a bright and deep national painted images typing, is specially emphasized. Overbalance of the lyrical narrative thematic invention, where folk type of the thematic invention makes to rearrange semantic accents in the genre interpretation, is identifi ed in “Variations on the Ukrainian Theme” by Gregory Tsitsalyuk. Improvisation, interpreted by the composer as a fi xed freedom, numerous brilliant colored soloist’s ritornels together with the main themes performing at the piano, broken chords, scale-wise passages – all marked methods indicate a high level of both externally-demonstrative and deep-semantic level of the music content. The arsenal of technical complexity methods of performing (articulation, strokes, complex elements), running on the disclosure of the musical work style; diversity of the texture design of musical thematic invention; genre and semantic specifi city (landscapes, personal experiences, household sketches, dance and song images), which is also connected with the balalaika specifi cs; and the dynamic profi le of musical drama cycle is detected. The idea of the historically formed specifi cs of textured and tonal articulation intoning on the balalaika in its academic status is adopted. Such levels of analysis like detection of existing texture and melodic formulas and connected with it fi ngering and articulation complex; timbre and texture and register variance confi rmed the instrumentalism genre specifi city. Articulation, timbre and texture technological formulas of balalaika performance, in terms of suite genre, which are universal from the point of view of the instrumental thinking specifi city, are found; their role in other genre and stylistic creativity conditions for balalaika are justifi ed. There are identifi ed such outlooks of research as the Concerto for balalaika and orchestra by P. Haydamakа, A. Gaidenko and the creation of a special “dictionary” as a system of typical historically selected texture and genre formulas. Piece, which reveal the balalaika evolution in the musical performing culture, served the basis for research. Current stylistic processes and their transformation in modern concert- and pedagogical practice were depicted in f piece for balalaika by G. Tsitsalyuk, P. Haydamakа, A. Gaidenko like in the mirror. Analyzed examples demonstrate the individual stylistic interpretation of genre, typical for the development of academic instrumentalism in the XX century. It was found, that art of balalaika performing infl uences the instrumental style of composing and keeps a memory of genre of composing and performing art in this sphere (methods of instrumental phonation and timbre- and phonic development).

AbstractA compact filtering ultra-wideband (UWB) microstrip power divider (PD) with two sharply rejected notch-bands and wide stopband is analyzed and designed in this paper. The proposed UWB PD is based on a conventional Wilkinson power divider, while two stub loaded resonators (SLRs) are coupled into two symmetrical output ports to achieve a bandpass filtering response. The simplified composite right/left-handed (SCRLH) resonators are employed to generate the dual notched bands. Defected ground structure (DGS) is introduced to improve the passband performance. Good insertion/return losses, isolation and notch-band rejection are achieved as demonstrated in both simulation and experiment.

For each malignant development type, simply slight characteristics are using. The quality perseverance work remains a difficult 1. To conquer this issue, all of us propose the double degree quality dedication Technique known as MRMR-SCOAHS. Within the principal stage, the base repeating and max-imam pertinence (MRMR) highlight willpower is employed to pick a subsection, subdivision, subgroup, subcategory, subclass of substantial qualities. The actual favored features are after that nourished right into a covering set up that combine another computation, SCOA-HS, making use of the help vector machine like a classifier. The particular strategy had been implemented in order to four microarray datasets, and also the exhibition has been broke down through forget about one particular crossacknowledgment method. Temporary performance investigation from the expert introduced strategy to developmental computations suggested that this proposed calculations amazing is better than other program in selecting a less amount of qualities whilst safeguarding the greatest order accuracy. The methods in the pre-owned attributes were furthermore explored, also it was accepted that they select qualities tend to be organically vital that you every malignancy type.

AbstractA novel compact ultra-wideband (UWB) bandpass filter (BPF) with a quad band-notched function using S-SCRLHs (splitted simplified composite right/left-handed) resonator is presented. The S-SCRLHs resonator, which exhibits quadruple resonance, is realized by coupling double S-SCRLH resonator. The S-SCRLHs resonator is integrated into a conventional UWB BPF. The notched frequencies can be adjusted according to specification by altering the S-SCRLHs resonator. Band-rejected filtering properties around the C-band satellite communication band, 5.2 GHz WLAN band and the X-band satellite communication band are generated. The notching frequencies are located at 4.2/5.2/6.3/7.8 GHz. Both simulated and measured results are provided with good agreement. Compared with other BPFs, the proposed BPF has the advantages of compact size, multi-stopband and good selectivity.

Abstract Background Cardiac magnetic resonance (CMR) imaging has recently been proposed to quantify lung water density (LWD, %) non-invasively. Given that pulmonary congestion plays a key role in the pathophysiology of Heart Failure (HF), we designed a study to assess the prognostic significance of a simplified LWD measure in patients with HF and reduced left ventricular ejection fraction (LVEF). Methods We conducted a single-center retrospective study of consecutive patients with HF and LVEF <50% who underwent CMR on a 1.5T scanner. Those with severe interstitial lung disease or chronic liver disease were excluded. All measurements were performed in a parasagittal plane at the right midclavicular line on a standard HASTE sequence, which is widely available in all CMR studies. As previously reported, LWD was determined by the lung-to-liver signal ratio multiplied by 0.7. A cohort of 102 healthy controls was used to derive the upper limit of normal (mean ± 2SD) of the LWD (21.2%). The primary endpoint was a composite of all-cause death or HF hospitalization. Results A total of 290 HF patients (mean age 64±12 years, 74.8% male, 56.2% of ischemic etiology) with a mean LVEF of 34±10% were included. LWD measurement took on average 35±4 seconds and showed excellent inter-observer agreement (intra-class correlation coefficient >0.90). LWD was increased in 65 (22.4%) patients. Compared to those with normal LWD, the former were more symptomatic (NYHA ≥III: 29.2% vs. 1.8%; p=0.017) and had higher median NT-proBNP [1973 (IQR: 809–3766) vs 802 (IQR: 355–2157pg/mL); p<0.001]. During a median followup of 21 months (IQR: 13–29), 20 (6.9%) patients died and 40 (13.8%) had at least one HF hospitalization. In multivariate analysis, LVEF (HR per 1%: 0.96; CI-95%: 0.93–0.99; p=0.024), creatinine (HR per 1mg/dL: 2.43; CI-95%: 1.25–4.71; p=0.009) and LWD (HR per 1%: 1.06; CI-95%: 1.01–1.12; p=0.013) were independent predictors of the primary endpoint. The findings were mainly driven by an association between LWD and HF hospitalization (HR per 1%: 1.08; CI-95%: 1.03–1.13; p=0.002). Conclusions A CMR-derived method for LWD quantification independently predicts an increased risk of death or HF hospitalization in HF patients with LVEF <50%. Our results support LWD measurement as a simple, reproducible and widely available method, further adding to the prognostic role of CMR in this population. Funding Acknowledgement Type of funding source: None


 
 
 Following the deep-seated analogy between biological and computer parasites, it is surely inconceivable that anyone would want to deliberately infect a computer. It’s a bad idea, right? Well, not necessarily. It seems that the University of Calgary (UoC) want to challenge the received wisdom of security experts—a judgment, which determines that there is no such thing as a good virus. The UoC wants to encourage their students to write and test malevolent viruses. Still following the biological analogy, Dr John Aycock, the academic who runs the program at UoC, likens the approach to ‘what medical researchers do to combat the latest biological viruses such as Sars’. He argues that ‘before you can develop a cure, you have to understand what the virus is and how it spreads and what motivates those who write malicious software’ (Fried). The reaction from security experts is not surprisingly one of dismay—for them, all viruses are bad.
 
 Nonetheless, it is Dr. Aycock’s provocation that may provide a much-needed alternative solution to one of the biggest problems facing the network society. As many affiliates of this composite society are increasingly discovering, the network is a present day communication paradox. It is a vast, fast, and efficient logic machine, but simultaneously it provides the perfect medium for viral contagion. Moreover, despite the efforts of a billion dollar anti-virus industry, current reactive solutions are clearly not working. A report in the UK (DTI) concludes that despite the considerable uptake of anti-virus software—93% of UK companies have anti-virus software—70% of all security breaches are from viral-like programs. (The DTI report claims that ‘two-thirds of organisations that had any security incident said that a virus infection was their worst one’. In comparison, a 1991 Gallup survey [in Louw and Duffy] showed that of 500 of the UK’s largest businesses 24% had experienced a viral attack.) Viruses, it seems, are progressively more capable of ‘bypassing traditional anti-virus software and targeting vulnerabilities’. However, Dr Aycock argues that academics should not bury their heads in the sand. They should openly recognise that ‘reacting to the virus is simply not working’ and instead support pro-active research into the creation of computer viruses. Within the bad idea itself there maybe a good solution. Naturally, the experts are outraged by what they perceive as an incursion beyond the ethical norms of the computer world. 
 
 These recent events are part of an ongoing good virus/bad virus debate. Network controllers have long argued for the ethical containment of viral code. Unlocking the secrets of the virus writer is, according to the anti-virus community, a bad idea. In the early 1980s, when Fred Cohen began experimenting with self-replicating code as part of his PhD, he experienced the moral indignation of the computer community. Cohen’s viral research at the University of Southern California (USC) referenced von Neumann’s seminal work on cellular automata (1948) and the Darwinian computer games played out in the Bell Labs in the 1950s and 1960s (Dewdney). Cohen was working on a similar, but simplified, idea, a ‘program’ that could insert itself into other programs and assume control of them. In doing so, he quickly realised the potential problem of the computer virus.
 
 I’d been working on computer security for a long time – I knew how systems worked, and how different attacks worked… But it came over me. Anyone who writes one of these things would have something that could replicate everywhere (Spiller 172).
 
 
 After seeing the results of his experiments, network controllers at USC banned him from repeating any similar exercises. Moreover, after completing his thesis in 1985, he could not get it published in a journal until 1987 (Spiller 176; it was finally published in the journal Computers and Security), and suffered a ‘virtual lockout’ in the funding of further research. Cohen later refers to the ‘apparent fear reaction’ as a result of trying to solve technical problems with policy solutions. At the time, Cohen used the same biological analogy as Dr. Aycock to defend his research into computer viruses. 
 
 The benefits of biological research on the quality of life is indisputable, and the benefits of computer virus research may some day pay off in the quality of our information systems, and by extension, our well being. (Cohen in Trends in Computer Virus Research)
 
 
 In the early 1990s, the network seemed to be a more open-minded society. Cohen was able to consider computer viruses in terms of the legitimacy of friendly contagion. The so-called benevolent virus appeared in his book A Short Course on Computer Viruses (Cohen 15). It was conceived of as a viral alternative to Turing logic. At the same time, physicist Mark Ludwig, driven by his desire to make technical information about computer viruses freely available, published the Black Book of Computer Viruses. Wired Magazine championed Ludwig’s ‘gruellingly meticulous analyses of viral performance and technique’ (Dibbell). In 1995, Tom Ray, a biologist turned computer programmer, created the viral-like Tierra program, an evolutionary race between digital hosts and parasites. Ray proposed that Tierra should exist in ‘a very large, complex and inter-connected region of cyberspace… inoculated with digital organisms, which will be allowed to evolve freely through natural selection’ (Ray)—ironically, something similar to what we are currently experiencing.
 
 In the early days, viral researchers were prompted to defend their work. In an interview in the virus webzine Alive in 1994, Cohen argued that a ‘symbol sequences without any known malicious side effects’ could not be considered as a bad idea. Ludwig contended that people were ‘brainwashed into believing that virus = bad…’ (Dibbell). However, more foreboding voices soon joined the debate. Spafford warned that while there is legitimate ‘scientific interest’ in viruses as a ‘means of modelling life’ and developing epidemiological defences, fellow researches should heed the dangers of further experimentation. True viruses are inherently unethical. For Spafford, the idea of a ‘good virus’ is an oxymoron.
 
 Following the exponential growth in malicious attacks in the mid-1990s, the idea of a good virus drifted considerably from the centre to the margins of the network society. In 1996, the IBM anti-virus researcher Sarah Gordon criticised Ludwig for elevating the status of the computer virus from the digital equivalent of a can of spray paint. With estimated costs to the worldwide Information Technolgy industry of $13 billion in 2001 (Pipkin 41) and the destructive force of a single worm costing tens of millions of dollars, not surprisingly the word ‘virus’ has developed a negative connotation. Even Cohen has realised that any acceptance of the benevolent virus would require considerable linguistic embellishment.
 
 Try ‘intelligent agents’, ‘artificial life’, ‘adaptive distributed networks’, and similar names and you will be far more successful. (Fed Cohen’s response to email questions posed by the author in June 2002)
 
 
 Within this heated climate, it was highly probable that Dr Aycock would stand accused of peddling a bad idea. Graham Cluley, a consultant for Sophos, rhetorically questions UoC’s ethics by asking, ‘should we teach kids how to break into cars if they’re interested in becoming a policeman one day?’ (Kelly). The anti-virus experts argue that by teaching how to ‘attack and destroy’ rather than ‘prevention, protection, and cure’, UoC will simply encourage the widespread contagion of the bad idea. However, UoC questions the naivety of this expert opinion. They argue that any ‘reasonably intelligent individual’ can access this information without attending university for four years. They claim it is ‘dangerous to think that virus writers can be stopped without a better understanding of how they operate.’ 
 
 Maybe UoC are doing what academia does best. They are considering the virus in a new and unfamiliar light, clearing away ethical baggage, and crossing the moral boundaries of the network society. Deep-seated as it is, the analogy only goes so far. The network and the virus writer have developed their own biology, which is both technologically and culturally shaped. The search for a viral cure has to move away from the reactionary dissection of existing viral anatomies. Researchers need to look towards a pro-active engineering model that incorporates the complex human-computer assemblage. As one maverick expert suggests: 
 
 Tomorrow’s experts need to learn to think beyond and develop better applications and operating systems that proactively block potential attack vectors rather than waiting to be attacked and then responding (a ‘security expert’ discussing the UoC programme in http://www.tla.ch/TLA/NEWS/2004sec/20040914Writting-Viruses.htm, 14 Sep. 2004)
 
 
 While many other types of furtive program, like ‘bots’, ‘crawlers’, and ‘spiders’ legitimately creep behind our screens, the virus is seen as a digital pariah. Whether or not the viral algorithm is benevolent or malevolent doesn’t seem to matter any more. The vast majority of the network society regards it as a bad idea. Nevertheless, Dr Aycock’s experiment with both the cultural and technological elements could produce a pro-active immunisation program. Whatever the conclusion, he should be applauded for attempting to carry out this experiment while beleaguered by so many experts who decide to judge innovation in terms of rigid moral outcomes. 
 
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 Sampson, Tony. "Dr Aycock's Bad Idea: Is the Good Use of Computer Viruses Still a Bad Idea?." M/C Journal 8.1 (2005). echo date('d M. Y'); ?> <http://journal.media-culture.org.au/0502/02-sampson.php>. APA Style
 Sampson, T. (Feb. 2005) "Dr Aycock's Bad Idea: Is the Good Use of Computer Viruses Still a Bad Idea?," M/C Journal, 8(1). Retrieved echo date('d M. Y'); ?> from <http://journal.media-culture.org.au/0502/02-sampson.php>. 

The continual (re)development associated with urban spaces results in the demand that heritage spaces be preserved. This raises a number of questions to be considered such as: which spaces will be preserved, what stories will be associated with these, and how will the embodied experience of these spaces be mediated? Since Foucault, it has been accepted that knowledge, power and truth are inextricably interwoven. There are no golden sands of freedom, there is no transcendent truth free from composing discourses. The construction of truth and history as discursive practice has a strong spatial component in museums. Objects are taken out of their original contexts, placed into knowledge regimes that delimit how these shall be known and then fixed in a stasis that regulates any change or flow in the meanings that might be constructed around these. Figure 1 - Skeleton of a middle age woman on display in the Dublinia MuseumThe body in the museum becomes either an object to be displayed or a nuisance to be excluded from contact with 'artefacts'. The picture above is of the skeleton of a middle age woman who died in Dublin hundreds of years ago and is now on display in the Dublinia Museum. Once the decision is made that this skeleton is no longer a body but an artefact it is placed behind glass so that the living bodies which come to view it may not 'interfere' with its discursive or physical existence. Once 'preserved' in this way, 'she' becomes an 'it', an object translated and removed from the everyday. In this case, the skeleton is placed within a scientific-medical discourse where the fact that it once belonged to an old woman who had worn away teeth tells us that she lived in a time when the people of Dublin had a poor diet. Similar undertakings are accepted practice in the Hyde Park Barracks Museum. All 'real' artefacts are kept behind glass, preserved in carefully controlled conditions that prevent human physical contact. Only replicas or reconstructions are available for everyday handling by the general public. In the example below, the item discussed was kept behind glass, a thing to be observed, revered, a relic to lend authority to the power-knowledge-truth regime of the Hyde Park Barracks Museum. Figure 2 - box containing a lock of Captain James Cook's hair and a rendition of his death scene in Hawaii on display at the Hyde Park Barracks MuseumSo 'precious' was this object that it was kept doubly removed, a small wooden casket within a timber and glass case behind the display panel of the museum. Figure 3 - closer view of box containing a lock of Captain James Cook's hair and a rendition of his death scene in Hawaii on display at the Hyde Park Barracks MuseumThis particular item contains a lock of Captain James Cook's hair and a rendition of his death scene in Hawaii. The case is made from the wood of the Resolution (his ship at the time of his death) and the entire item was a memento given to his widow upon the Resolution's return to Britain. This 'relic' is iconic of the approach adopted by the presentation of the Barracks as a museum. But what happens when the history being 'preserved' is the fabric of a built space? The spatial process of 'encasing', 'preserving' and physically removing 'artefacts' from everyday contact is an ongoing aspect of the presentation of the Barracks. In 1996, not long after I began my employ with the Barracks as part of an extended engagement with the embodied experience of cityspace, the curator decided that each guide should have their skills at presenting the Barracks in an appropriate light assessed. The result was that each guide was required to prepare and present a 'wall talk'. The 'wall talk' was literally that. Each guide was assigned a physical section of the museum to research and then discuss for ten minutes to an audience composed of other guides, the curator, the manager and education staff. The aims were to get each guide to re-assess their lecture presentation technique and to spread awareness amongst the guides that each physical section of the museum held its own unique part in the story of the Barracks. My assignment was a piece of wall on the second floor directly above the reception area. Deep into the persona I created so that I could 'pass' in this environment, I began by examining the wall. It was constructed of the convict made brick laid down in 1818 held together by Aboriginal midden material that dated back thousands of years, overlaid with whitewash applied in 1848 when the men moved out and the women moved in, the whitewash was overlaid with plaster held in place by cows hair in 1887 when the building was converted to a courts complex which was topped with remnants of wall paper that dated back to 1952 when the room was renovated as a Judge's chambers. On a section of the wall that had once been covered by this wallpaper was a pencil drawn outline of a pair of scissors, the name Max Fry and the date 1952 was written next to these. Both the floor and ceiling above and below the wall had sections that had been replaced when air conditioning was installed in the first incarnation of the building as a museum under the management of the Museum of Applied Arts and Sciences. A red builders' chalk mark showing where this was to installed remained even though the ducting had been removed in a later enactment of this museum space under the auspices of the Historic Houses Trust. In the rebated corner closest to this wall, out of sight to any but the closest inspection, there was a pencil drawing of a boxer shaping up to an unseen opponent. The skirting board was two inches higher than in the next room and of an Edwardian rather than a Victorian style. 'Ghosts' from zinc tiles were etched upon the ceiling and scratch marks from the iron beds used by the immigrant women remained upon the floors. I considered the wall carefully and even more carefully thought about the discourses of this institution, the personality of the curator and the predilections of the manager and other guides. If I was to continue 'passing', which story should I tell? How should it be told? What emphasis should be made and, most importantly of all, what must be elided? I considered raising the awareness that anthrax spores had been found in similar cow-hair reinforced plaster in the London Tube system but this somehow seemed irreverent. Starting with an statement about the mortar, Aboriginal land claims and how the entire Historic Houses Trust functioned to legitimate European seizure of Aboriginal land and that this was reflected by the way in which Aboriginal artefacts were ignored seemed equally inadvisable. Perhaps a discussion of the judge who inspired the boxer was in order. Rumour had it that he used to pay 'taxi-drivers' to join him in his rooms and engage in a little 'wrestling' and 'boxing'. This was reputedly such a physical activity that grunts, groans and cries of pain (?) were heard throughout the building. I could talk about the rats that had infested the ceilings above and below the room from the time that false ceilings were put in place during the renovation of the building into a courts complex and perhaps even display some of the 'artefacts' that had been stolen by the rats and hidden under the floor or in the ceiling space. A straight 'history' of the wall that simply discussed its physical composition would have 'passed', but that was perhaps more superficial than I felt the material warranted. Instead, set to a background audio tape of Tracey Chapman singing "Talking Bout a Revolution", a selection from Pink Floyd's The Wall and The Beatles Revolution 9, I told a story about the scissors. The scissors tale began by introducing Max Fry as a humble paperhanger working in the chambers of a powerful Judge in the 1950's. Oppressed, voiceless, the only impact he could make within the Barracks was to trace his scissors, sign his name, date it and then paper over this minor act of rebellion. For nearly thirty years his legacy remained hidden under the paper as judge after judge used the room to write the judgements that ordered the lives of those unfortunate enough to pass before them. In 1979 this legacy was unveiled but ignored, covered over by an air-conditioning system decreed necessary to preserve the artefacts displayed in the building. This oversight was rectified (so my story went) by the current generation of carers for the heritage of the building when the air conditioning was removed and the slice of social history and iniquitous power relations that Max Fry's rebellion illustrated was put on display for all to see. The talk was received well by all except for the chief guide who felt the music was distracting. He wanted me to do another wall some other time and 'get it right this time'. The curator was delighted and over-ruled the chief guide and the wall talks were over as far as I was concerned. A few months later, I was surprised to discover that on one of my 'time in lieu' breaks from the Barracks, that the wall had been encased in glass. The original scissors whose outline was traced upon the now preserved wall had been 'rescued' from Max's tool shed and hung behind the glass along with a picture of himself and some other of his tools. A story panel iterated a simplified version of the story I had told that elided any reference to class inequality or the powerlessness of his position. History's truth and permanence was now safely assured and no meddling fingers would ever again touch the pencilled scissored outline or smudge the bleary red chalk-line. The boxer, however, remains un-encased, a few hands-breadths from Max's sanitised and now unapproachable history, awaiting the right 'story' to bring it to prominence and preservation. Citation reference for this article MLA Style Darrell, Aaron. "Whose History?" M/C: A Journal of Media and Culture 5.2 (2002). [your date of access] < http://www.media-culture.org.au/0205/history.php>. Chicago Style Darrell, Aaron, "Whose History?" M/C: A Journal of Media and Culture 5, no. 2 (2002), < http://www.media-culture.org.au/0205/history.php> ([your date of access]). APA Style Darrell, Aaron. (2002) Whose History?. M/C: A Journal of Media and Culture 5(2). < http://www.media-culture.org.au/0205/history.php> ([your date of access]).