scholarly journals Do We Need Many-valued Logics for Incomplete Information?

2019 ◽  
Author(s):  
Marco Console ◽  
Paolo Guagliardo ◽  
Leonid Libkin
Keyword(s):  
Incomplete Information ◽  
Relational Databases ◽  
Predicate Logic ◽  
Truth Values ◽  
Design Choice ◽  
Null Values ◽  
Epistemic Approach ◽  
The Many ◽  
The Right ◽  
Sql Query

One of the most common scenarios of handling incomplete information occurs in relational databases. They describe incomplete knowledge with three truth values, using Kleene's logic for propositional formulae and a rather peculiar extension to predicate calculus. This design by a committee from several decades ago is now part of the standard adopted by vendors of database management systems. But is it really the right way to handle incompleteness in propositional and predicate logics? Our goal is to answer this question. Using an epistemic approach, we first characterize possible levels of partial knowledge about propositions, which leads to six truth values. We impose rationality conditions on the semantics of the connectives of the propositional logic, and prove that Kleene's logic is the maximal sublogic to which the standard optimization rules apply, thereby justifying this design choice. For extensions to predicate logic, however, we show that the additional truth values are not necessary: every many-valued extension of first-order logic over databases with incomplete information represented by null values is no more powerful than the usual two-valued logic with the standard Boolean interpretation of the connectives. We use this observation to analyze the logic underlying SQL query evaluation, and conclude that the many-valued extension for handling incompleteness does not add any expressiveness to it.

scholarly journals Relational theories with null values and non-herbrand stable models

2012 ◽  
Vol 12 (4-5) ◽  
pp. 565-582 ◽  
Author(s):  
VLADIMIR LIFSCHITZ ◽  
KARL PICHOTTA ◽  
FANGKAI YANG
Keyword(s):  
Incomplete Information ◽  
Relational Databases ◽  
Logic Program ◽  
Answer Set Programming ◽  
First Order ◽  
Relational Theories ◽  
Null Values ◽  
Closure Assumption ◽  
General Method ◽  
Stable Models

AbstractGeneralized relational theories with null values in the sense of Reiter are first-order theories that provide a semantics for relational databases with incomplete information. In this paper we show that any such theory can be turned into an equivalent logic program, so that models of the theory can be generated using computational methods of answer set programming. As a step towards this goal, we develop a general method for calculating stable models under the domain closure assumption but without the unique name assumption.

Closed Sets of Boolean Terms in Relational Databases

1991 ◽  
Vol 14 (3) ◽  
pp. 367-385
Author(s):  
Andrzej Jankowski ◽  
Zbigniew Michalewicz
Keyword(s):  
Computational Complexity ◽  
Incomplete Information ◽  
Relational Databases ◽  
The Other ◽  
New Approach ◽  
Closed Sets ◽  
Null Value ◽  
Algebraic Operations

A number of approaches have been taken to represent compound, structured values in relational databases. We review a few such approaches and discuss a new approach, in which every set is represented as a Boolean term. We show that this approach generalizes the other approaches, leading to more flexible representation. Boolean term representation seems to be appropriate in handling incomplete information: this approach generalizes some other approaches (e.g. null value mark, null variables, etc). We consider definitions of algebraic operations on such sets, like join, union, selection, etc. Moreover, we introduce a measure of computational complexity of these operations.

Governmental Censorship in War-Time

1942 ◽  
Vol 36 (5) ◽  
pp. 837-849 ◽  
Author(s):  
Byron Price
Keyword(s):  
National Security ◽  
Free Enterprise ◽  
Individual Liberty ◽  
News Stories ◽  
Radio Industry ◽  
Democratic Principles ◽  
The Many ◽  
The Right ◽  
Free People ◽  
Magazine Articles

To a free people, the very word “censorship” always has been distasteful. In its theory, it runs counter to all democratic principles; in practice, it can never be made popular, can never please anyone.Everything the censor does is contrary to all that we have been taught to believe is right and proper. The Post Office Department, for example, has two proud mottoes: “The mail must go through,” and “The privacy of the mail must be protected at all hazards.” But censorship stops the mail, it invades the privacy of the mail, it disposes of the mail as may seem best. The same thing holds true in the publishing business. Censorship limits the lively competition and free enterprise of reporters. It relegates many a scoop to the waste basket. It wields a blue pencil—both theoretical and actual—on news stories, magazine articles, advertisements, and photographs. Censorship also enters the radio industry, where it may edit scripts and in some cases stop entire programs.Yet even the most vociferous critics of the principle of censorship agree that in war-time some form and amount of censorship is a necessity. It then becomes not merely a curtailment of individual liberty, but a matter of national security. It is one of the many restrictions that must be imposed on people fighting for the right to throw off those restrictions when peace returns.

An Aid in Selecting the Brand, Size and Other Strategic Choices for a Hotel

1997 ◽  
Vol 21 (1) ◽  
pp. 71-99 ◽  
Author(s):  
Richard C. Morey ◽  
David A. Dittman
Keyword(s):  
Best Practices ◽  
Operations Management ◽  
Final Decision ◽  
Facility Design ◽  
Strategic Choices ◽  
Suggested Approach ◽  
Brand Building ◽  
Explicit Consideration ◽  
The Many ◽  
The Right

The “go/no-go” decision for a candidate property, i.e., whether or not to actually acquire the site, choose the brand (flag), build and operate the hotel, requires the explicit consideration of the interconnectedness of the many myriad elements affecting the property's potential profits. The many facility design decisions (number and mix of rooms, capacity for F&B operations etc.) as well as other strategic choices (e.g., size of marketing program, level of service aimed for) must recognize the site's competitive features and interactions with the above. Also, the particular design and operational features for a given property will affect its different revenue streams, fixed and variable costs, efficiency and profits. The authors consider developers contemplating acquiring a given site, choosing a brand, building and operating a new hotel. They offer a normative approach for this type of decision which arrives endogenously at possibly attractive options for the brand, design and strategic choices for the site. The final decision as to which option to actually use, if any, should be based on subjecting the above identified scenarios, as well as others, to traditional feasibility analyses where judgment and expert opinion are applied. The authors' implementable approach integrates a “best practices” benchmarking methodology with regression analysis to yield a mathematical programming optimization model. A key advantage of this approach lies in its contrast to conventional approaches for site selection which often ignore the more detailed design and strategic choices. The approach deals explicitly with the complex interfaces between marketing and operations management as the endogenous site and competitive environmental factors interact with the endogenous brand and facility design choices. By identifying attractive options to be further explored (that might otherwise be overlooked), several types of errors are avoided: i) an incorrect “go/no go” decision could be recommended for the site in question; ii) even if the right decision to proceed is made, the forecasted level of annualized profits could be in error, leading to an incorrect priority for the activity; iii) the incorrect brand and facility design choices could be made for the site. Other key advantages of the suggested approach are that 1) various substitution possibilities (between more or less capital, labor, materials etc.) are considered; 2) not only is the best brand and configuration identified, but also a ranking of other brands is available if the “best” brand is not available; 3) the “best practices” at other specific sites (which serve as the basis for the recommendations) are identified, thereby enabling management (possibly through site visits) to isolate the actual cultures, processes and procedures to be transported and emulated at the candidate site. This paper illustrates the approach for two different sites.

scholarly journals Mussolini Predicted a Fascist Century: How Wrong Was He?

Fascism ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Roger Griffin
Keyword(s):  
Twentieth Century ◽  
World Wide ◽  
Local Level ◽  
Modern World ◽  
Benito Mussolini ◽  
New Developments ◽  
The Many ◽  
The Right ◽  
Wide Community

In the entry on ‘Fascism’ published in 1932 in the Enciclopedia Italiana, Benito Mussolini made a prediction. There were, he claimed, good reasons to think that the twentieth century would be a century of ‘authority’, the ‘right’: a fascist century (un secolo fascista). However, after 1945 the many attempts by fascists to perpetuate the dreams of the 1930s have come to naught. Whatever impact they have had at a local level, and however profound the delusion that fascists form a world-wide community of like-minded ultranationalists and racists revolutionaries on the brink of ‘breaking through’, as a factor in the shaping of the modern world, their fascism is clearly a spent force. But history is a kaleidoscope of perspectives that dynamically shift as major new developments force us to rewrite the narrative we impose on it. What if we take Mussolini’s secolo to mean not the twentieth century, but the ‘hundred years since the foundation of Fascism’? Then the story we are telling ourselves changes radically.

Teaching the Future of Technology in the History Classroom: A Case Study

2018 ◽  
Vol 10 (4) ◽  
pp. 253-262 ◽  
Author(s):  
David J. Staley
Keyword(s):  
Incomplete Information ◽  
The State ◽  
Historical Inquiry ◽  
Social Scientists ◽  
Traditional Methods ◽  
Research Seminar ◽  
Historical Method ◽  
The Future ◽  
The Right

This article will describe how historians can teach the future of technology. Historians need not alter their traditional methods of historical inquiry to teach the future, and indeed the history classroom is a natural site for foresight education. Historical inquiry begins with questions, and futuring similarly begins with asking the right questions. The historian seeks out evidence, and futurists as well identify drivers and blockers, considering how these drivers and blockers will interact with each other. In contrast to social scientists, historians work with imperfect or incomplete information, an apt description of the state of our evidence about the future. In a manner similar to historians, futurists interpret and draw inferences from evidence. After the research an analysis of the evidence is complete, the historian/futurist writes representations. This article will describe how I employed the historical method to teach the future of technology in a history research seminar, the results produced by the students, and ways that the study of the future can be situated in the history classroom.

scholarly journals Ruptured Bilateral Pericallosal Artery Aneurysm in Mirror Position: Case Report

2018 ◽  
Vol 37 (03) ◽  
pp. 263-266
Author(s):  
Lucas Meguins ◽  
Linoel Valsechi ◽  
Ronaldo Fernandes ◽  
Dionei Morais ◽  
Antonio Spotti
Keyword(s):  
Case Report ◽  
Subarachnoid Hemorrhage ◽  
External Ventricular Drain ◽  
Artery Aneurysm ◽  
Operative Management ◽  
Neurological Deficits ◽  
Pericallosal Artery ◽  
Digital Subtraction Arteriography ◽  
The Many ◽  
The Right

Introduction Pericallosal artery (PA) aneurysms represent 2 to 9% of all intracranial aneurysms, and their management remains difficult. Objective The aim of the present study is to describe the case of an adult woman with subarachnoid hemorrhage and bilateral PA aneurysm in mirror position. Case Report A 46-year-old woman was referred to our institution 20 days after a sudden severe headache. She informed that she was treating her arterial hypertension irregularly, and consumed ∼ 20 cigarettes/day. The patient was neurologically intact at admission. A non-contrast computed tomography (CT) on the first day of the onset of the symptoms revealed hydrocephaly and subarachnoid hemorrhage (Fisher III). An angio-CT/digital subtraction arteriography showed bilateral PA aneurysms in mirror position. The patient was successfully treated with surgery via the right interhemispheric approach (because the surgeon is right-handed); the surgeon performed the proximal control with temporary clipping, and introduced an external ventricular drain at the end of the surgery. The patient was discharged on the fourth postoperative day without any additional neurological deficits or ventricular shunts. Conclusion Ruptured PA aneurysm is a surgically challenging aneurysm due to the many anatomical nuances and risk of rebleeding. However, the operative management of ruptured bilateral PA aneurysms is feasible and effective.

scholarly journals Grand Duchess Alexandra Petrovna (nun Anastasia) and the activities of the Pokrovsky monastery-hospital in Kiev in the late XIX and early XX century

2015 ◽  
Vol 96 (3) ◽  
pp. 471-477
Author(s):  
N N Blokhina
Keyword(s):  
Medical Care ◽  
Medical Equipment ◽  
Economic Activities ◽  
Medical Settings ◽  
New Methods ◽  
Novel Treatment ◽  
Work Atmosphere ◽  
The Many ◽  
The Right ◽  
Special Atmosphere

The article describes the activities of the Pokrovsky monastery-hospital in Kiev, created by the efforts of the Grand Duchess Alexandra Petrovna (1838-1900), who took the monastic vows in 1889 under the name Anastasia. The monastery became widely known in the late XIX - early XX century for the highly skilled medical aid provided to the population since its inception up to the events of 1917. It was a unique complex of medical settings located in the same area and equipped with modern medical equipment comparable with the many World’s clinics of that time. In this monastery-hospital, pilgrims with different diseases who came at Pokrovsky monastery in Kiev were provided the required qualified, affordable medical care. Thanks to the Grand Duchess Alexandra Petrovna, her attentive attitude to all the latest innovations, novel treatment methods were developed and introduced to the work of monastery medical settings. In addition, she was able to create a special atmosphere and goodwill towards the sick. But, being engaged in devising new methods of providing medical care to patients, she was able to create a special and inviting atmosphere with respect to the patient. With the ever-increasing circle of her organizational and economic activities, being in charge of the monastery-hospital problems of great importance, Grand Duchess reserved the right to nurse her patients. She worked by vocation, at the behest of the soul. Her example of selfless labor in the monastery medical settings where monastic sisters held the medical staff responsibilities for the patients care was important for all of the staff. Her assistants - Sisters of Charity - she fostered by her own example of selfless aid to a sick person. This favorable work atmosphere was very effective helping cure the sick.

Foundations of American Conservatism

1947 ◽  
Vol 41 (6) ◽  
pp. 1105-1117
Author(s):  
W. Hardy Wickwar
Keyword(s):  
National Policy ◽  
The United States ◽  
General Will ◽  
Distinctive Character ◽  
Comparative Political Theory ◽  
Nineteenth Century America ◽  
American Conservatism ◽  
Age Of Reason ◽  
The Many ◽  
The Right

To the student of comparative political theory, few things are more fascinating than the contrast not only between different ages but also between different countries in one and the same age. The greatest advances in the collective thinking of Western humanity have been made coöperatively by men of every nation; and in every age all unite to give to that age its own distinctive character; yet each people contributes something of its own national genius to the spirit of the age. He, then, who would understand a country and the pattern of its people's thinking does well to inquire in what way it has deviated from the thinking of other nations in particular epochs.Whoever looks at early nineteenth-century America must be struck by its aloofness from many of the main currents of Western thinking. In the great Revolution of the eighteenth century, it had not been thus. The Lockean and Blackstonean tradition of the right of Englishmen to protect their property through representative organs; Rousseau's concept of equal natural rights of every individual and the right of the sovereign people in convention to reconstitute society according to its general will; Montesquieu's advocacy of checks and balances as safeguards of liberty; Quesnay's physiocratic cult of land as the natural source of wealth and power; Adam Smith's analysis of the relationship between national policy and private commerce; deism in religion; and associationism in psychology—these were among the many trends in the Age of Reason that came to a focus in the revolt of the thirteen colonies and the establishment of the United States.

HOAX DALAM TINJAUAN HADITS NABAWI

Al-MAJAALIS ◽  
2018 ◽  
Vol 6 (1) ◽  
pp. 147-179
Author(s):  
Ali Musri Semjan Putra
Keyword(s):  
Social Media ◽  
Business Education ◽  
Sex Trafficking ◽  
Islamic Law ◽  
The Other ◽  
The World ◽  
Information Media ◽  
Severe Punishment ◽  
The Many ◽  
The Right

Among the proofs of the greatness of God's power in the millennium is the emergence of various kinds of information media that are very helpful for ease in various matters. The convenience covers various fields of affairs, not just in the form of sharing information but has penetrated into the fields of business, education, da'wah and so on.Besides the many positive sides of social media, on the other hand social media is also a vehicle for various negative actions, such as hoaxes, fighting, sex trafficking, drug sales and so on. So this study tries to examine the nabawi hadiths relating to things that must be heeded in social media, specifically those related to hoaxes, with the induction approach using qualitative analysis. The purpose of the research is to provide insight to the community in using social media so that there is no violation of religious teachings or legislation when integrating on social media. As well as being a wrong solution in tackling and minimizing various forms of irregularities and violations that occur in the community in social media, both offenders in the form of crimes of intimidation, provocation, fraud, counterfeiting and so on, are spurred from hoax news.The conclusion of this study is that making or spreading hoaxes is an act that is strictly prohibited and prohibited in the nabawi hadiths which are the second source of law in Islamic law after the noble Qur'an. The culprit has the right to be punished in the world in a criminal manner or get a severe punishment in the hereafter, according to the effects and headlines of the lies he did.

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