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Row hammer

Row hammer is a security exploit that takes advantage of an unintended and undesirable side effect in dynamic random-access memory in which memory cells leak their charges by interactions between themselves leaking or changing the contents of nearby memory rows that were not addressed in the original memory access. This bypass of the isolation between DRAM memory cells results from the high cell density in modern DRAM, can be triggered by specially crafted memory access patterns that activate the same memory rows numerous times. While cell charge leakage is normal and mitigated by refreshes, additional leakage occurs during a rowhammer attack which causes cells to leak enough charge to change its content within a refresh interval; the row hammer effect has been used in some privilege escalation computer security exploits, network-based attacks are theoretically possible in a fast network connection between the attacker and victim. Different hardware-based techniques exist to prevent the row hammer effect from occurring, including required support in some processors and types of DRAM memory modules.

Row hammer or never affects DDR and DDR2 SDRAM modules. It affects many DDR3 and DDR4 SDRAM modules. In dynamic RAM, each bit of stored data occupies a separate memory cell, electrically implemented with one capacitor and one transistor; the charge state of a capacitor is what determines whether a DRAM cell stores "1" or "0" as a binary value. Huge numbers of DRAM memory cells are packed into integrated circuits, together with some additional logic that organises the cells for the purposes of reading and refreshing the data. Memory cells are further addressed through rows and columns. A memory address applied to a matrix is broken into the row address and column address, which are processed by the row and column address decoders. After a row address selects the row for a read operation, bits from all cells in the row are transferred into the sense amplifiers that form the row buffer, from which the exact bit is selected using the column address. Read operations are of a destructive nature because the design of DRAM requires memory cells to be rewritten after their values have been read by transferring the cell charges into the row buffer.

Write operations decode the addresses in a similar way, but as a result of the design entire rows must be rewritten for the value of a single bit to be changed. As a result of storing data bits using capacitors that have a natural discharge rate, DRAM memory cells lose their state over time and require periodic rewriting of all memory cells, a process known as refreshing; as another result of the design, DRAM memory is susceptible to random changes in stored data, which are known as soft memory errors and attributed to cosmic rays and other causes. There are different techniques that counteract soft memory errors and improve the reliability of DRAM, of which error-correcting code memory and its advanced variants are most used. Increased densities of DRAM integrated circuits have led to physically smaller memory cells capable of storing smaller charges, resulting in lower operational noise margins, increased rates of electromagnetic interactions between memory cells, greater possibility of data loss.

As a result, disturbance errors have been observed, being caused by cells interfering with each other's operation and manifesting as random changes in the values of bits stored in affected memory cells. The awareness of disturbance errors dates back to the early 1970s and Intel 1103 as the first commercially available DRAM IC. However, researchers proved in a 2014 analysis that commercially available DDR3 SDRAM chips manufactured in 2012 and 2013 are susceptible to disturbance errors, while using the term row hammer to name the associated side effect that led to observed bit flips; the opportunity for the row hammer effect to occur in DDR3 memory is attributed to DDR3's high density of memory cells and the results of associated interactions between the cells, while rapid DRAM row activations have been determined as the primary cause. Frequent row activations cause voltage fluctuations on the associated row selection lines, which have been observed to induce higher-than-natural discharge rates in capacitors belonging to nearby memory rows, which are called victim rows.

Tests show that a disturbance error may be observed after performing around 139,000 subsequent memory row accesses, that up to one memory cell in every 1,700 cells may be susceptible. Those tests show that the rate of disturbance errors is not affected by increased environment temperature, while it depends on the actual contents of DRAM because certain bit patterns result in higher disturbance error rates. A variant called double-sided hammering involves targeted activations of two DRAM rows surrounding a victim row: in the illustration provided in this section, this variant would be activating both yellow rows with the aim of inducing bit flips in the purple row, which in this case would be the victim row. Tests show that this approach may result in a higher rate of disturbance errors, compared to

Dhaka District

Dhaka District is a district in central Bangladesh, is the densest district in the nation. It is a part of the Dhaka Division. Dhaka, the capital of Bangladesh, rests on the eastern banks of the Buriganga River which flows from the Turag to the south of the district. While Dhaka occupies only about a fifth of the area of Dhaka district, it is the economic and cultural centre of the district and the country as a whole. Dhaka district consist with Dhaka city, Nababganj, Dohar and Dhamrai upazila. Dhaka District is an administrative entity, like many other cities, it does not cover the modern conurbation, Greater Dhaka, which has spilled into neighbouring districts, nor does the conurbation cover the whole district, as there are rural areas within the district; the administrative Dhaka District was first established in 1772. But, the existence of urbanised settlements in the area, now Dhaka city – dates from the 7th century; the present day Savar was the capital of the Sanbagh Kingdom during eighth century.

The city area of Dhaka was ruled by the Buddhist kingdom of Kamarupa and the Pala Empire before passing to the control of the Hindu Sena dynasty in the 9th century. Many believe that the name of the city was derived after the establishment of the Goddess Dhakeshwari's temple by Ballal Sena in the 12th century. Dhaka and its surrounding area was identified as Bengalla around that period; the town itself consisted of a few market centres like Lakshmi Bazar, Shankhari Bazar, Tanti Bazar, Kumartuli, Bania Nagar and Goal Nagar. After the Sena dynasty, Dhaka was successively ruled by the Turkish and Afghan governors descending from the Delhi Sultanate before the arrival of the Mughals in 1608; the development of townships and a significant growth in population came as the city was proclaimed the capital of Bengal under Mughal rule in 1608. During Mughal rule the areas under Dhaka district was famous for its textile products – the Muslin. Mughal subahdar Islam Khan was the first administrator of the city.

Khan named the town "Jahangir Nagar" in honour of the Mughal emperor Jahangir, although this name was dropped soon after Jahangir's death. The main expansion of the city took place under Mughal general Shaista Khan; the city measured 19 by 13 kilometres, with a population of nearly a million people. The city passed to the control of the British East India Company in 1757 after the Battle of Plassey and to the Crown, British Empire, in 1765 at the Battle of Buxar; the city's population shrank during this period as the prominence of Kolkata rose, but substantive development and modernisation followed. A modern civic water supply system was introduced in 1874 and electricity supply launched in 1878; the Dhaka Cantonment was established near the city, serving as a base for British and Indian soldiers. During the abortive Partition of Bengal in 1905, Dhaka was declared to be the capital of the newly established state of Eastern Bengal and Assam, but Bengal was reunited in 1911; the rural areas under present Dhaka district Dohar Upazila were used for the production of indigo.

Following the partition of Bengal in appending the partition of British India in 1947, Dhaka became the capital of East Bengal as a part of the new Muslim state of Pakistan, while western part of Bengal with a majority Hindu population had become a part of the new and independent India, designated as West Bengal with Calcutta as state capital. Calcutta witnessed communal violence. A large proportion of the city's Hindu population departed for India, while the city received hundreds of thousands of Muslim immigrants from Calcutta, India; the city's population rose in a short period of time, which created severe shortages and infrastructural problems. As the centre of regional politics, Dhaka saw an increasing number of political strikes and incidents of violence; the adoption of Urdu as the sole official language of Pakistan led to protest marches involving large crowds. Known as the language movement of 1952, the protests resulted in police firing which killed students who were demonstrating peacefully.

Throughout the 1950s and'60s, Dhaka remained a hotbed of political activity, the demands for autonomy for the Bengali population gained momentum. The 1970 Bhola cyclone devastated much of the region. More than half the city of Dhaka was flooded and millions of people marooned. With public anger growing against ethnic discrimination and poor cyclone relief efforts from the central government, Bengali politician Sheikh Mujibur Rahman held a nationalist rally on 7 March 1971 at the Race Course Ground. An estimated one million people attended the gathering, leading to Ziaur Rahman's 26 March declaration of Bangladesh's independence. In response, the Pakistan Army launched Operation Searchlight, which led to the arrests and killing of hundreds of thousands of people Hindus and Bengali intellectuals. During the Bangladesh Liberation War the Pakistan army arrested and killed fourteen Muktijoddhas from Dhamrai Bazar. A mass grave created during the war still exists in the western side of Kalampur Bazar.

The Pak army burnt down many houses in Konakhola, Brahmankirtha and Khagail Kholamora villages of Keraniganj Upazila. The fall of Dhaka city to the allied forces led by Jagjit Singh Aurora on 16 December marked the surrender of Pakistan army; the post-independence period has seen a rapid and massive growth of the city population, attracting migrant workers from rural areas across Bangladesh. A real estate boom has followed the expansion of city limits and th

Kesenai Tsumi

"Kesenai Tsumi" is the debut single by Japanese rock singer Nana Kitade. The song was used as the first ending theme to the anime Fullmetal Alchemist; the single reached #14 on the Oricon Charts and stayed on the charts for a total of twenty-two weeks, selling a total of 65,525 copies. The music video for "Kesenai Tsumi" starts out with the image of a doll version of Kitade, being pieced together. Throughout the video are images of pale red flowers, masks floating in a bubbly space and Kitade in a black dress. At the end of the video, Kitade is shown human, singing against a blue backdrop with the words "Debut" and "北出菜奈" in white text. "Kesenai Tsumi: Raw "Breath" Track" is an acoustic rearrangement of the song. It was released a month after the original "Kesenai Tsumi"; the single reached charted for eleven weeks on the Oricon Charts. Official Website Sony Music Japan

Peter McCullagh

Peter McCullagh is an Irish statistician and John D. MacArthur Distinguished Service Professor in the Department of Statistics at the University of Chicago. McCullagh is from Northern Ireland, he attended the University of Birmingham and completed his PhD at Imperial College London, supervised by David Cox and Anthony Atkinson. McCullagh is the coauthor with John Nelder of Generalized Linear Models, a seminal text on the subject of generalized linear models with more than 23,000 citations, he wrote "Tensor Methods in Statistics", published in 1987. McCullagh is the American Academy of Arts and Sciences, he won the COPSS Presidents' Award in 1990. He was the recipient of the Royal Statistical Society's Guy Medal in Bronze in 1983 and in Silver in 2005, he was the recipient of the inaugural Karl Pearson Prize of the International Statistical Institute, with John Nelder, "for their monograph Generalized Linear Models". He won a Notable Alumni Award in 2007 from his grammar school, St Columb's College

Balagarh (community development block)

Balagarh is a community development block that forms an administrative division in Chinsurah subdivision of Hooghly district in the Indian state of West Bengal, the headquarter of the block is located in Jirat. The Balagarh CD Block is part of the Hooghly Flats, one of the three natural regions in the district of the flat alluvial plains that forms part of the Gangetic Delta; the region is a narrow strip of land along the 80 km long stretch of the Hooghly River, that forms the eastern boundary of the district. The region has been physiographically influenced by the course of the river; the western part of the block merges into the Hooghly-Damodar Plain. Balagarh is located at 23°06′34″N 88°27′37″E. Balagarh CD Block is bounded by Santipur and Ranaghat I CD Blocks, in Nadia districts across the Hooghly, in the north, Ranaghat I CD Block, in Nadia district across the Hooghly the east, Chinsurah Mogra CD Block in the south and Pandua and Kalna II CD Blocks, in Bardhaman district, in the west, it is located 30 km from the district headquarters.

Balagarh CD Block has an area of 202.15 km2. It has 1 panchayat samity, 13 gram panchayats, 183 gram sansads, 135 mouzas and 129 inhabited villages. Balagarh police station serves this block. Headquarters of this CD Block is at Jirat. Gram panchayats of Balagarh block/ panchayat samiti are: Jirat, Dumurdaha-Nityanandapur I, Dumurdaha-Nityanandapur II, Guptipara I, Guptipara II, Bakulia-Dhobapara, Siza-Kamalpur, Somra I, Somra II and Sripur-Balagarh; as per the 2011 Census of India, Balagarh CD Block had a total population of 228,998, of which 200,810 were rural and 28,188 were urban. There were 112,870 females. Population below 6 years was 21,396. Scheduled Castes numbered 93,402 and Scheduled Tribes numbered 21,129; as per the 2001 census, Balagarh block had a total population of 214,710, out of which 110,121 were males and 104,589 were females. Balagarh block registered a population growth of 15.40 per cent during the 1991-2001 decade. Decadal growth for Hooghly district was 15.72 per cent. Decadal growth in West Bengal was 17.84 per cent.

Census Towns in Balagarh CD Block: Badhagachhi, Mirdhanga and Jirat. Large villages in Balagarh CD Block: Aida Kismat, Nutan Char Krishnabati, Dakshin Gopalpur and Serpur. Other villages in Balagarh CD Block included: Guptipara, Patuli; as per the 2011 census the total number of literates in Balagarh CD Block was 159,735 out of which males numbered 87,232 and females numbered 72,503. The gender disparity was 11.05%. As per the 2001 census, Balagarh block had a total literacy of 50.07 per cent. While male literacy was 68.38 per cent, female literacy was 49.98 per cent. See – List of West Bengal districts ranked by literacy rate As per the 2001 census, Bengali is the mother tongue for 86.4% of the population of the district followed by Hindi at 7.9%. Santali at 2.6% and Urdu at 2.0%, are the two other major languages spoken in the district. The population who reported Bengali as a mother tongue has decreased from 88.1% in 1961 to 86.4% in 2001 census whereas the population who reported Hindi as mother tongue has increased from 5.8% in 1961 to 7.9% in 2001 census.

As per the 2011 census, majority of the population of the district belong to the Hindu community with a population share of 82.9% followed by Muslims at 15.8%. The percentage of the Hindu population of the district has followed a decreasing trend from 87.1% in 1961 to 82.9% in the latest census 2011. On the other hand, the percentage of Muslim population has increased from 12.7% in 1961 to 15.8% in 2011 census. In 2011 census Hindus formed 89.24 % of the population in Balagarh CD Block. Muslims formed 8.81 % of the population. Others formed 1.95 % of the population. As per poverty estimates obtained from household survey for families living below poverty line in 2005, rural poverty in Balagarh CD Block was 11.19%. In Balagarh CD Block in 2011, amongst the class of total workers, cultivators formed 15.95%, agricultural labourers 42.99%, household industry workers 4.34% and other workers 36.72%. There are 129 inhabited villages in Balagarh CD Block. 100% villages have power supply. 108 villages have more than one source of drinking water, 19 villages have only tube well/ borewell and 2 villages have only hand pump.

7 Villages have post offices, 16 villages have sub post offices and 3 villages have post and telegraph offices. 118 villages have landlines, 80 villages have public call offices and 126 villages have mobile phone coverage. 67 villages have pucca roads and 56 villages have bus service. 15 villages have agricultural credit societies, 22 villages have commercial/ co-operative banks and 3 villages have ATMs. Balagarh was selected the site for power station by Calcutta Electric Supply Corporation but the project was shelved. According to C. E. S. C. Web Journal of 16 April 2010 it will be revived by them. Balagarh's economy specially depends on building of country boats and manufacture of tiles, famous all over India. Amongst the primary and other hats or markets in the Balagarh block area are at: Jeerat and Semra; the Tebhaga movement launched in 1946, in 24 Parganas district, aimed at securing for the share-croppers a better position within the existing

Before the Fall (2004 film)

Before the Fall is a 2004 German drama film written and directed by Dennis Gansel. It is centered around the National Political Institutes of Education or "NaPolA" schools created under the government of Nazi Germany; these military academies were designed as preparatory schools for the future Nazi political and military elite. In 1942, Friedrich Weimer's boxing skills earn him an appointment to a National Political Academy, a high school that serves as an entry to the Nazi elite, his father, a skilled factory worker who despises the Nazis, flatly refuses to allow Friedrich to enroll. Friedrich, who sees the school as his ticket to university and a better life, forges his father's signature on the permission form and leaves during the night, he makes his way to the town of Allenstein, where the school is located, getting a ride from passing cars or trucks when possible and walking the rest of the way. Friedrich's forged papers are overlooked, he is taken by fellow student, Christoph Schneider to be kitted out in the school Nazi style uniform.

Friedrich is unaware of the true purpose of the school and is impressed in his first day at Allenstein. However, Friedrich's idealistic view of Allenstein is soon tarnished by the harsh, rigid discipline that governs the school. Older students are able to bully younger students at will, since there is little interference from school officials, who not only encourage such behavior but participate in it themselves. One boy, Siegfried Gladen, endures repeated public humiliation for his tendency to wet the bed as he sleeps; the school teaches the Nazi Party creed to its students, with sections of Hitler's speeches and writings being analyzed in classes. "Survival of the fittest" is advocated as the natural way of life, Jews and all other enemies of the state are presented as treacherous and by nature inferior. The boxing trainer who got Friedrich appointed works with him one-on-one, teaching Friedrich to be hard and ruthless in fights, dismissing any kind of compassion for the other boxer as "bullshit".

Back at his room, Friedrich receives a letter from his mother, informing him that his father has been paid a visit by the Gestapo. Friedrich visits Albrecht one evening, finding him in a writing and mail office that the students use. Albrecht confides that his talents lie in writing and the arts, areas his father sees as unfit for men, his mother is more supportive but is just as disinterested. Albrecht begins taking advice and criticism from Friedrich; when Friedrich has his first competitive boxing match against another NaPolA school, he overpowers the other boy, knocking him down into a corner. Urged on by the shouts of his trainer and other students and officials, he delivers a brutal knockout punch, winning the match. Friedrich is congratulated by staff and students alike. One day, the seventh-year boys are taken to the trenches on school grounds, where the sports instructor demonstrates use of live stick grenades; each of the boys in Friedrich's year make the throw until one boy, Martin and drops it.

The sports instructor flees the trench, leaving the boys to their fate. At that moment, Siegfried Gladen pushes through the ranks and dives on the grenade a second before it explodes. Gauleiter Heinrich Steiner arrives to make a speech at the funeral, praising Siegfried Gladen as a martyr of the Fatherland and posthumously awarding him the Lifesaving Medallion. Albrecht invites Friedrich to come with him to the Steiner family's home, a vast mansion in the countryside. Heinrich Steiner returns home for his birthday, treated to a special dinner by his wife and a group of friends from the Nazi Party, German Army, Waffen-SS, he wastes no time criticizing Albrecht for his artistic manner and lack of athletic talent. A boxer himself, Heinrich Steiner is far more interested in Friedrich than in his own son, delights in Albrecht's inability to compete with Friedrich when the two are taken downstairs and forced to fight a boxing match. During the winter, a group of military vehicles arrives at the school at night.

The entire seventh-year class is called outside, where Gauleiter Heinrich Steiner informs them that a group of Soviet POW's have overpowered their guards, stolen weapons, escaped from the nearby village. The boys are sent into the woods to search for them. Friedrich and Albrecht, assigned to the same group, end up deep in the frozen woods. Abruptly, a group of figures come out of hiding and try to run back over the crest of a nearby hill, ignoring the boys' shouts to halt; the boys open fire. Moving closer, they are shocked to find that not only were none of the prisoners armed, but they were all young boys, no older than the German students. A horrified Albrecht vainly tries to bandage the wounds of one prisoner still left alive, but his father arrives with a search party and shoots the Russian; as the boys are taken back to Allenstein, they see the rest of the POW's being rounded up and hear a long, rattling fusillade of gunfire in the woods. In class the next day, Albrecht reads aloud an essay in which he condemns the execution of the Soviet POW's as a criminal act and his own participation in it as "evil".

Outraged, school authorities summon his father, who coldly informs Albrecht that he will write a new essay, starting with an apology for his previous statements. Albrecht instead writes a second essay in which he condemns his father for ordering the POW's executed. Learning that Albrecht is to be expelled from school and drafted into the Waffen-SS to fight on the Eastern