Evolution Of Defence Industry In India History Essay

Evolution Of Defence Industry In India History Essay 12. The history of DIB in India dates back to 1775 when British authorities accepted setting up of Board of Ordnance in Fort William, Kolkata. This was the official beginning of the Army Ordnance in India. In 1787 a gun powder factory was established at Ishapore which started production from 1791  [1]  . However, the first ordnance factory, Gun Shell factory was established at Cossipore in 1801 to manufacture guns and ammunition.  [2]  Since then the DIB in British ruled India grew to 7 Ordnance Factories (OFs) by the end of WWI and 18 OFs at the time of independence1, generally catering to repair overhaul and supplementing weapons and equipment produced in Britain. During this period India was never allowed to develop core competencies in industrial production. Post Independence up to 1960s 13. Post independence the Indian leadership aimed at attaining self-sufficiency in entire domain of defence production. To achieve this Industry Policy Resolution 1948 and The Industries (Development Regulation) Act, 1951  [3]  emphasized core industries (including defence sector) be taken care of by central government. Hence, eight Defence Public Sector Units (DPSUs) were established under aegis of Government, to undertake defence production. Defence Science Organisation(DSO), which was established to take up challenges of RD, got amalgamated with technical development establishment (TDE) in 1958. Hence, DRDO was created which then comprised of 10 laboratories  [4]  . Post 1962 War 14. Post 1962 war license production and direct purchase remained predominant form of supply for armed forces. This resulted in a gap of nearly three decades in Indias effort toward indigenous production which was especially evident in the fields of RD. A fighter aircraft between Marut and the Light Combat Aircraft (LCA), a basic trainer aircraft between HT-2 and HPT- 32, an intermediate trainer between Kiran and yet-to-be fully developed Advanced Jet Trainer (AJT) are some of the examples that typify both technology and production gaps  [5]  . Trends in 1980s and 1990s 15. During this period Global defence expenditure touched its peak in 1987 and then fell sharply in late 1980s and early 1990s. This period also saw globalization with countries opening up their economies, rise in low intensity conflicts, lawlessness, crimes and terrorism. This period was the starting point of major defence acquisitions from abroad coupled with major initiatives in indigenous defence production, including RD. The license production of Jaguars and MiG-27M was undertaken by HAL  [6]  . This period also saw commencement of indigenous development of LCA, ALH, MBT Arjun by DRDO and missiles under Integrated Guided Missile Development Programme (IGMDP) by Bharat Dynamics Limited (BDL). However, fructification of these projects was accompanied by inordinate delays and technological gaps. 16. With nothing forthcoming from indigenous RD, the mainstay of armed forces was met through substantial arms acquisition from abroad. With the change in environment after nuclear explosions by India and Pakistan and the Kargil conflict, the country had to give a re-look to its defence strategy including its objective of achieving self-reliance in defence industry. Defence Industry in 21st Century 17. The importance of civil military interaction to attain near self-reliance in defence production was realized and this period saw changes at institutional and organizational levels as recommended by GoM Committee Report on Reforming the National Security System. The major shift in policy was allowing 100% private sector participation and 26% Foreign Direct Investment (FDI) in defence-industrial sector  [7]  . Confederation of Indian Industries (CII) has been instrumental in influencing such a marked change in policy. While these far-reaching institutional and policy-oriented changes have been underway for quite some time, the demand for private participation has assumed significance in recent years. Trends in Global Defence Industry 18. Cold War era saw an upward trend in military demand followed by a reverse trend in post cold war era. Reduction in defence budget allocation  [8]  in the post cold war period, as shown in Table 1 resulted in many smaller companies either merging with big ones or shifting towards civilian production. Mergers and acquisitions resulted in creation of few giant companies like Boeing, Lockheed Martin, British Aerospace, Northrop Grumman and EADS. As shown in Table, the military expenditure again witnessed upward trend since 1999 and this is likely to continue in future  [9]  . With procurement budgets increasing new opportunities are expected for the defence industry. In the changing conflict scenario, there has been an upward trend in the LIC, insurgency, terrorism, OOAC etc as a result of which the global defence industry after a period of significant downsizing and rationalization has entered into a phase of renewed attention. Table 1: Stockholm International Peace Research Institute (SIPRI): Military Expenditure Database in GDP 1988 2009. Indias Defence Industry. 19. Post Cold War era, changing trends in global defence industry had affected Indian DIB. Economic liberalization has resulted in indigenous build-up of technological base in IT, communication, electronics, automobile sectors etc. Since, all defence acquisitions till mid 90s were either outright or under license production/TOT, DPSUs/OFs could only gain expertise in production by assembling Completely knock Down (CKD) and/or Semi knock Down (SKD) Kits imported from the Original equipment manufacturer (OEM). The real TOT aimed at enhancing the indigenous development was missing in all these deals. However, the most far reaching change, in recent times, that has impacted the Indias DIB is opening up of defence sector for private participation. The objectives are manifold viz., reduction of defence imports from current levels of 70 percent, increase in defence exports, enhance the indigenous RD skill level and infrastructure to produce state of the art equipment within time frames spec ified. In Jan 2001, the GOI initiated a series of major initiatives that included FDI up to about 26 percent and full private participation in certain sectors in defence industry. However, licensing requirement was still an impediment towards luring private industries. Shift from Self Sufficiency to Self-Reliance 20. Since independence Indias Industry Policy Resolution of 1948 and 1951 was aimed at achieving self sufficiency in defence production. Towards this the government invested heavily in scientific and technological institutions such as IITs, CSIR, ICAR, DAE, DoS, ICMR, DRDO etc. However, the countrys defence was neglected, as was evident in 1962 war. With a weak DIB, the policies to maximize production in order to attain self-sufficiency in defence sector although were considered farsighted, did not match expectations, thus leading to shift of focus from self-sufficiency model to self reliance model. 21. Self-reliance in its true sense does not preclude accessing external sources for technology and systems, or external help in any stage of the production cycle. Hence, self-reliance meant apart from Indias own production base for support a degree of dependence on reliable foreign sources for access to technologies, supply of components and complete systems was desirable. These were materialized by meeting urgent and immediate demands through imports form abroad while simultaneously striving for indigenous capabilities in defence production. Although Indias main focus on imports was from western countries like UK, France, Sweden these countries were reluctant in supplying defence equipment to India post 1962 war. Indias quest for self reliance got a major boost when Russia agreed for licence production by various DPSUs as well as OFs in India. However, in the bargain TOT aimed at enhancing indigenous production and RD activities lost focus. The outcome of this is obvious, as witn essed in the LCA program, MBT Arjun and aero engine Kaveri. In spite of having produced aircraft, tanks and aero engines under Licence Production, the organizations involved in the production could hardly assimilate and nurture the technology needed to supplement our own indigenous efforts. Probably the focus of these organizations was more towards production rather than indigenization. Analysis 22. Thus, the approach that India adopted in defence procurement and defence industrial development can be divided into three stages. The first stage was from independence till 1962 when all defence needs were met from overseas procurement. The second stage was from 1962 till mid-1980s when efforts were made to build domestic production through licence production. The third stage from mid-1980s until the present day not only saw procurement from Russia and France, but also initiation of a number of indigenous RD projects. 23. Prior to independence, the focus of DIB was primarily aimed at supplementing the equipment produced in Britain. Various committees such as the Chatfield committee in 1938, Roger Mission, the Eastern Group 1940 and the Grady Mission 1942 were formed to look into issues relating to Indias defence production  [10]  . The Grady Mission could not find a single person or department with whom they could discuss issues pertaining to defence production in India. Hence, the mis-management of the defence production in India dates back from colonial era and the heritage continues even today with the defence RD and production sector still being neglected by the bureaucracy and the political giants. 24. Globally, Military technology has grown from the era of vacuum tube and electromechanical systems of early 19th century to miniaturized electronics and software driven sophisticated systems. Till the cold war era, Military Doctrine drove technology. However, in the fast-changing technological world, technology is driving military doctrines. NOTES AND REFERENCES

Harmonic Elimination

336 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 22, NO. 1, JANUARY 2007 Modulation-Based Harmonic Elimination Jason R. Wells, Member, IEEE, Xin Geng, Student Member, IEEE, Patrick L. Chapman, Senior Member, IEEE, Philip T. Krein, Fellow, IEEE, and Brett M. Nee, Student Member, IEEE Abstract—A modulation-based method for generating pulse waveforms with selective harmonic elimination is proposed. Harmonic elimination, traditionally digital, is shown to be achievable by comparison of a sine wave with modi? d triangle carrier. The method can be used to calculate easily and quickly the desired waveform without solution of coupled transcendental equations. Index Terms—Pulsewidth modulation (PWM), selective harmonic elimination (SHE). I. INTRODUCTION S ELECTIVE harmonic elimination (SHE) is a long-established method of generating pulsewidth modulation (PWM) with low baseband distortion [1]–[6]. Originally, it was useful mainly for inverters with naturally low switching frequency due to high power level or slow switching devices.Conventional sine-triangle PWM essentially eliminates baseband harmonics for frequency ratios of about 10:1 or greater [7], so it is arguable that SHE is unnecessary. However, recently SHE has received new attention for several reasons. First, digital implementation has become common. Second, it has been shown that there are many solutions to the SHE problem that were previously unknown [8]. Each solution has different frequency content above the baseband, which provides options for ? attening the high-frequency spectrum for noise suppression or optimizing ef? iency. Third, some applications, despite the availability of high-speed switches, have low switching-to-fundamental ratios. One example is high-speed motor drives, useful for reducing mass in applications like electric vehicles [9]. SHE is normally a two-step digital process. First, the switching angles are calculated of? ine, for several depths of modulation, by sol ving many nonlinear equations simultaneously. Second, these angles are stored in a look-up table to be read in real time. Much prior work has focused on the ? st step because of its computational dif? culty. One possibility is to replace the Fourier series formulation with another orthonormal set based on Walsh functions [10]–[12]. The resulting equations are more tractable due to the similarities between the rectangular Walsh function and the desired waveform. Another orthonormal set approach based on block-pulse functions is presented in [13]. In [14]–[20], it is observed that Manuscript received August 2, 2006; revised September 11, 2006.This work was supported by the Grainger Center for Electric Machines and Electromechanics, the Motorola Center for Communication, the National Science Foundation under Contract NSF 02-24829, the Electric Power Networks Ef? ciency, and the Security (EPNES) Program in cooperation with the Of? ce of Naval Research. Recommended for publ ication by Associate Editor J. Espinoza. J. R. Wells is with P. C. Krause and Associates, Hentschel Center, West Lafayette, IN 47906 USA. X. Geng, P. L. Chapman, P. T. Krein, and B. M.Nee are with the Grainger Center for Electric Machines and Electromechanics, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA (e-mail: [email  protected] edu). Digital Object Identi? er 10. 1109/TPEL. 2006. 888910 the switching angles obtained traditionally can be represented as regular-sampled PWM where two phase-shifted modulating waves and a â€Å"pulse position modulation† technique achieve near-ideal elimination. Another approximate method is posed by [21] where mirror surplus harmonics are used. This involves solving multilevel elimination by considering reduced harmonic elimination waveforms in each switching level.In [22], a general-harmonic-families elimination concept simpli? es a transcendental system to an algebraic functional problem by zeroing entire harmonic fami lies. Faster and more complete methods have also been researched. In [23], an optimal PWM problem is solved by converting to a single univariate polynomial using Newton identities, Pade approximation theory, and symmetric function properties, which . If a few can be solved with algorithms that scale as O solutions are desired, prediction of initial guess values allows rapid convergence of Newton iteration [24].Genetic algorithms can be used to speed the solution [25], [26]. An approach that guarantees all solutions ? t a narrowly posed SHE problem transforms to a multivariate polynomial system [27]–[30] through trigonometric identities [31] and solves with resultant polynomial theory. Another approach [32]–[34] that obtains all solutions to a narrowly-posed problem uses homotopy and continuation theory. Reference [35] points out the exponentially growing nature of the problem and proposes the â€Å"simulated annealing† method as a way to rapidly design the wavef orm for optimizing distortion and switching loss.Another optimization-based approach is given in [36] and [37], where harmonics are minimized through an objective function to obtain good overall harmonic performance. There have been several multilevel and approximate real-time methods proposed; these are beyond the scope here but discussed brie? y in [38]. This manuscript proposes an alternative real-time SHE method based on modulation. A modi? ed triangle carrier is identi? ed that is compared to an ordinary sine wave. In place of the conventional of? ine solution of switching angles, the process simpli? s to generation and comparison of the carrier and sine modulation, which can be done in minimal time without convergence or precision concerns. The method does not require an initial guess. In contrast to other SHE methods, the method does not restrict the switching frequency to an integer multiple of the fundamental. The underlying idea was proposed in [39] but has been re? ned he re to identify speci? c carrier requirements that exactly eliminate harmonics and improve performance in deeper modulation. The method involves a function of modulation depth that is derived from simulation and curve ? ting. In this respect, it has some similarity to [15] and [16], in which approximate switching angles are calculated and ? tted to simple functions for cases of both low-( 0. 8 p. u. ) and high-modulation depth. It is interesting that the proposed approach connects modulation to a harmonic elimination process. Carrier waveform mod- 0885-8993/$25. 00  © 2007 IEEE IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 22, NO. 1, JANUARY 2007 337 Fig. 1. Direct calculation of the phase modulation function at various modulation depths with ? rst through 109th harmonics controlled.Fig. 2. Direct calculation of the phase modulation function at various modulation depths with ? rst through 177th harmonics controlled. i? cation is common in other PWM work, as in switching frequency ra ndomization intended to reduce high-frequency components. A detailed review is outside the scope, but one discussion is given in [40]. The proposed technique is not a variation of random-frequency carriers. Instead, the carrier waveform is modi? ed in a speci? c and deterministic way to bring about a certain effect. The proposed method is readily implemented in real time.The switching signals themselves can be generated by analog comparison, while the modi? ed carrier is generated with fast digital calculation and digital-to-analog conversion. Hardware demonstration is provided here. An approximate, low-cost implementation based on present-day hardware is given in [41], but further re? nement is needed for precise elimination. II. SIGNAL DEFINITIONS AND SIMULATED RESULTS Consider a quasi-triangular waveform to be used as the carrier signal in a PWM implementation. In principle, the frequency and phase can be modulated.To represent this, consider a triangular carrier function written as (1) where is the base switching frequency, is a phase-mod0, (1) reulation signal, and is a static phase shift. For duces to an ordinary triangle wave based on conventional quadrant de? nitions of the inverse cosine function. The modulating where signal will be represented as is the depth of modulation. The pulsewidth-modulated signal, , is 1 if and 1, otherwise. 2 In [39], a phase modulation function is considered, where is the desired output fundamental fre, but dequency. This was shown to approach SHE at low 0. . To determine a better phase-modulagrades above tion function, the pattern of switching angles that occurs was investigated. Fig. 1 shows the phase modulation values needed for various with harmonics 1–109 conversus angle trolled. Fig. 2 shows the same with harmonics 1–177 controlled. Many other sets of controlled harmonics were tested with similar results. The pattern looks much like a shockwave pattern that can be modeled with the Bessel–Fubini e quation from nonlinear acoustics [42] (2) where is a Bessel function of the ? rst kind. The natural is in? ity in principle, but for calculation purposes number 15 or higher is usually suf? cient, as discussed below. The and have been determined by curve functions ? tting as (3) 1. and (4), shown at the bottom of the page, where 0 Fig. 3 shows a closeup view of a PWM waveform generated as in (2). Nineteen harmonics are with a carrier that uses 0. 95. The waveform is compared controlled with a (high) to one generated with conventional elimination by numerical solution of nonlinear equations. As can be seen, the switching edges match well. Fig. 4 shows a full-period time waveform and a magnitude 11.With spectrum [fast Fourier transform (FFT)] for this switching frequency ratio, the method eliminates harmonics two through ten (even harmonics are zero by symmetry). The 2 and the modulation depth carrier phase shift is set to 1. The spectrum con? rms the desired elimination. is 0. This v alue Fig. 5 shows the same study except with also achieves satisfactory baseband performance, but with a different pulse pattern. The pattern provides slight differences in higher-order harmonics. For example, the 11th and 13th harto . monics vary 2%–3% in magnitude as is varied from (4) 338IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 22, NO. 1, JANUARY 2007 Fig. 3. Conventional harmonic elimination waveform and proposed PWM 0. 95, harmonics controlled through the 19th). waveform (m = Fig. 5. Pulse waveform p, message signal m, and magnitude of pulse waveform 1, and ‘ 0. spectrum for ! =! 11, m = = = Fig. 4. Pulse waveform p, message signal m, and magnitude of pulse waveform spectrum for ! =! 11, m 1, and ‘ =2. = = = In these cases, all baseband harmonics are eliminated. In three-phase systems, triplen harmonics may cancel in the currents automatically if neutral current does not ? w. Therefore it is not always necessary to eliminate them by design in the SHE pro cess. Modulation-based harmonic elimination excluding triplen harmonics is similar in many respects to the case here. However, the phase-modulation functions resemble piecewise polynomials rather than the shockwave form of Figs. 1 and 2. This is discussed in detail in [38]. The speed of calculating these waveforms is dictated by , the number of terms to keep in the series (2), and , the number of discrete points used to approximate the waveforms. A personal computer (1. 86-GHz Intel M Processor with 1. -GB RAM) running MATLAB on Windows XP was used to carry out the calculations. First, a modi? ed triangle wave was ap100 000 points per cycle, the modulation proximated with 1, and a frequency ratio of 19 was used. depth was set to was varied from ? ve to 35. Over this range, the The number quality of solution was acceptable and the average calculation time varied from 0. 327 to 0. 915 s. Next, the same conditions 35 and was varied from 10 000 were used with except to 200 000. The aver age calculation time varied almost linearly from 0. 149 to 1. 78 s with no signi? cant difference in the resulting spectrum.Finally, with held constant at 100 000, the frequency ratio was varied from seven to 51. The average calculation time was consistently near 0. 92 s. This is expected since the number of harmonics eliminated has no scaling effect in (2). However, for larger frequency ratios, larger may be needed for precision. In summary, it is recommended that be set to at least 1,000 the frequency ratio and set to at least 15. In any case, with present-day personal computers the solution can be calculated in less than 1 s (typically) without iteration, divergence, or need for an initial estimate, and reduced versions can be computed in less than 200 ms.Notice that this time interval need not cause trouble with real-time implementations. The carrier only needs to be recomputed with the modulation signal changes. In applications such as uninterruptible supplies, this is infreque nt. In motor-drive applications, a response time of 200 ms to a command change may be acceptable as is. Alternatively, a look-up table can store some of the relevant terms to speed up the process dramatically. Dedicated DSP Please de? ne DSPalgorithms will be much faster than PC computations based on MATLAB. III. EXPERIMENTAL EXAMPLES To show that the proposed technique satisfactorily eliminates harmonics, the modi? d carrier was programmed into a function generator. The output provided a carrier signal in a conventional sine-triangle process. Three examples are shown below to reveal a range of interesting conditions. Fig. 6 shows the resulting waveforms for a high-depth case 0, and 0. 95. The with nineteen harmonics eliminated, and are shown at frequency ratio is 21:1. The signals the top, followed by the PWM waveform and the FFT spectrum. From the spectrum it can be seen that the desired harmonic-free baseband spectrum is achieved. In the next example, the phase 2.The unexpected r esult was that the spectrum shift is was insensitive to , as shown in comparison to Fig. 7. The desired spectrum occurs despite the difference in carriers. The resulting PWM waveforms at various values of may not offer obvious advantages, but it is noteworthy that they are not the same as conventionally computed SHE waveforms and would not be achievable with conventional SHE solution techniques. As another example, it is shown that the carrier base fre, need not be an odd multiple of . In Fig. 8, the frequency, IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 22, NO. 1, JANUARY 2007 339 Fig. . Experimental modulation-based SHE with ! ‘ 0. = =! = 21, m = 0. 95, Fig. 9. Experimental modulation-based SHE with ! ‘ 0. = =! = 13. 5, m = 0. 95, Fig. 7. Experimental modulation-based SHE with ! ‘ =2. = =! = 21, m = 0. 95, Fig. 10. Experimental modulation-based SHE with ! ‘ 0. = =! = 50, m = 0. 95, The last example, shown in Fig. 10, applies to a case where a high number of harmonics is eliminated (50 1 ratio) effectively, which is much higher than typically are reported in the literature. IV. CONCLUSION A method for calculating and implementing SHE switching angles was proposed and demonstrated.The method is based on modulation rather than solution of nonlinear equations or numerical optimization. The approach is based on a modi? ed carrier waveform that can be calculated based on concise functions requiring only depth of modulation as input. It rapidly calculates the desired switching waveforms while avoiding iteration and initial estimates. Calculation time is insensitive to the switching frequency ratio so elimination of many harmonics is straightforward. It is conceivable the technique could be realized with low-cost microcontrollers for real-time implementation.Once the carrier is computed, a conventional carrier-modulator comparison process produces switching instants in real time. REFERENCES [1] F. G. Turnbull, â€Å"Selected harmonic reduc tion in static dc-ac inverters,† IEEE Trans. Commun. Electron. , vol. CE-83, pp. 374–378, Jul. 1964. Fig. 8. Experimental modulation-based SHE with ‘ 0. = ! =! = 20, m = 1. 0, quency ratio is adjusted to be 20:1, with 0, and now 1. 0. The same nineteen harmonics are eliminated, but now the switching frequency is 5% lower. Intervals during which the carrier waveform is not triangular can be seen in the ? gure. As shown in Fig. , the frequency ratio can also be a half-in0. 95 and 0. teger. In this case, the ratio is 13. 5:1, 340 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 22, NO. 1, JANUARY 2007 [2] H. S. Patel and R. G. Hoft, â€Å"Generalized techniques of harmonic elimination and voltage control in thyristor inverters: part I-harmonic elimination,† IEEE Trans. Ind. Appl. , vol. IA-9, no. 3, pp. 310–317, May/ Jun. 1973. [3] ——, â€Å"Generalized techniques of harmonic elimination and voltage control in thyristor inverters: part II-vol tage control techniques,† IEEE Trans. Ind. Appl. , vol. IA-10, no. 5, pp. 666–673, Sep. /Oct. 1974. [4] I.J. Pitel, S. N. Talukdar, and P. Wood, â€Å"Characterization of programmed-waveform pulsewidth modulation,† IEEE Trans. Ind. Appl. , vol. IA-16, no. 5, pp. 707–715, Sep. /Oct. 1980. [5] ——, â€Å"Characterization of programmed-waveform pulse-width modulation,† in Proc. 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Roman Civil War: Compare 69 Ce and 193 Ce

Civil War: compare 69 CE and 193 CE. Consider the issues of imperial Succession, the roles of the senate, military importance, and the ultimate settlement. How were they the same and different. The Year of the Four Emperors was a year in the history of the Roman Empire, AD 69, in which four emperors ruled in a remarkable succession. These four emperors were Galba, Otho, Vitellius, and Vespasian. The suicide of emperor Nero, in 68, was followed by a brief period of civil war, the first Roman civil war since Mark Antony's death in 30 BC. Between June of 68 and December of 69, Rome witnessed the successive rise and fall of Galba, Otho and Vitellius until the final accession of Vespasian, first ruler of the Flavian Dynasty. This period of civil war has become emblematic of the cyclic political disturbances in the history of the Roman Empire. The military and political anarchy created by this civil war had serious repercussions, such as the outbreak of the Batavian rebellion. (The Jewish Revolt was already ongoing. )Vespasian did not meet any direct threat to his imperial power after the death of Vitellius. He became the founder of the stable Flavian dynasty that succeeded the Julio-Claudians and died of natural causes as emperor in 79. The Year of the Five Emperors refers to the year 193 AD, in which there were five claimants for the title of Roman Emperor. The five were Pertinax, Didius Julianus, Pescennius Niger, Clodius Albinus and Septimius Severus. The year 193 opened with the murder of Commodus on New Year's Eve, 31 December 192 and the proclamation of the City Prefect Pertinax as Emperor on New Year's Day, 1 January 193. Pertinax was assassinated by the Praetorian Guard on 28 March 193. Later that day, Didius Julianus outmaneuvered Titus Flavius Sulpicianus (Pertinax's father-in-law and also the new City Prefect) for the title of Emperor. Flavius Sulpicianus offered to pay each soldier 20,000 sestertii to buy their loyalty (eight times their annual salary; also the same amount offered by Marcus Aurelius to secure their favours in 161). Didius Julianus however offered 25,000 to each soldier to win the auction and was proclaimed Emperor by the Roman Senate on 28 March. However, three other prominent Romans challenged for the throne: Pescennius Niger in Syria, Clodius Albinus in Britain, and Septimius Severus in Pannonia. Septimius Severus marched on Rome to oust Didius Julianus and had him decapitated on 1 June 193, then dismissed the Praetorian Guard and executed the soldiers who had killed Pertinax. Consolidating his power, Septimius Severus battled Pescennius Niger at Cyzicus and Nicea in 193 and then decisively defeated him at Issus in 194. Clodius Albinus initially supported Septimius Severus believing that he would succeed him. When he realised that Severus had other intentions, Albinus had himself declared Emperor in 195 but was defeated by Septimius Severus at the Battle of Lugdunum on 19 February 197.

How to Discipline Without Stress, Punishment, or Rewards

Young people today come to school with a different orientation than past generations. Traditional student disciplining approaches are no longer successful for far too many young people. For example, a parent related the following to us after a discussion of how society and youth have changed in recent generations: The other day, my teenage daughter was eating in a rather slovenly manner, and I lightly tapped her on the wrist saying, Dont eat that way.My daughter replied, Dont abuse me.The mother had grown up in the 1960s and volunteered the point that her generation tested authority but most were really afraid to step out of bounds. She related that her daughter was a good child and added, But the kids today not only disrespect authority, they have no fear of it. And, because of rights for young children—which we should have—its hard to instill that fear without others claiming abuse. So, how can we discipline students, so we as teachers can do our jobs and teach these young children who refuse to learn? In many cases, we resort to punishment as a strategy for motivation. For example, students who are assigned detention and who fail to show are punished with more detention. But in my questioning about the use of detention in hundreds of workshops around the country, teachers rarely suggest detention is actually effective in changing behavior. Why Detention is an Ineffective Form of Punishment When students are not afraid, punishment loses its effectiveness. Go ahead and give the student more detention that he simply wont show up to. This negative, coercive discipline and punishment approach is based on the belief that it is necessary to cause suffering to teach. Its like you need to hurt in order to instruct. The fact of the matter, however, is that people learn better when they feel better, not when they feel worse. Remember, if punishment were effective in reducing inappropriate behavior, then there would be NO discipline problems in schools. The irony of punishment is that the more you use it to control your students behaviors, the less real influence you have over them. This is because coercion breeds resentment. In addition, if students behave because they are forced to behave, the teacher has not really succeeded. Students should behave because they want to—not because they have to in order to avoid punishment. People are not changed by other people. People can be coerced into temporary compliance. But internal motivation—where people want to change—is more lasting and effective. Coercion, as in punishment, is not a lasting change agent. Once the punishment is over, the student feels free and clear. The way to influence people toward internal rather than external motivation is through positive, non-coercive interaction. Heres how... How to Motivate Students to Learn Without Using Punishments or Rewards Great teachers understand that they are in the relationship business. Many students—especially those in low socio-economic areas—put forth little effort if they have negative feelings about their teachers. Superior teachers establish good relationships AND have high expectations. Great teachers communicate and discipline in positive ways. They let their students know what they want them to do, rather than by telling students what NOT to do. Great teachers inspire rather than coerce. They aim at promoting responsibility rather than obedience. They know that OBEDIENCE DOES NOT CREATE DESIRE. Great teachers identify the reason that a lesson is being taught and then share it with their students. These teachers inspire their students through curiosity, challenge, and relevancy. Great teachers improve skills that prompt students to WANT to behave responsibly and WANT to put effort into their learning. Great teachers have an open mindset. They REFLECT so that if a lesson needs improvement they look to themselves to change BEFORE they expect their students to change. Great teachers know education is about motivation. Unfortunately, todays educational establishment still has a 20th-century mindset that focuses on EXTERNAL APPROACHES to increase motivation. An example of the fallacy of this approach is the defunct self-esteem movement that used external approaches such as stickers and praise in attempts to make people happy and feel good. What was overlooked was the simple universal truth that people develop positive self-talk and self-esteem through the successes of THEIR OWN EFFORTS.