A generalized form of the Raychaudhuri equation

2021 ◽  
pp. 2150092
Author(s):  
Indranath Bhattacharyya ◽  
Saibal Ray
Keyword(s):  
Raychaudhuri Equation ◽  
Physical Implication ◽  
Special Cases

In this work, we have attempted to generalize the Raychaudhuri equation by using the concept of foliation of spacetime. Some studies are performed with a few special cases and their physical implication are discussed.

Electron Beam Damage of Biomolecules Assessed by Energy Loss Spectroscopy

1978 ◽  
Vol 36 (3) ◽  
pp. 61-69
Author(s):  
M. Isaacson ◽  
M.L. Collins ◽  
M. Listvan
Keyword(s):  
Electron Microscopy ◽  
Radiation Damage ◽  
Structural Integrity ◽  
Analytical Electron Microscopy ◽  
High Dose ◽  
Dose Rates ◽  
Special Cases ◽  
Analytical Electron ◽  
Atom Migration ◽  
Beam Damage

Over the past five years it has become evident that radiation damage provides the fundamental limit to the study of blomolecular structure by electron microscopy. In some special cases structural determinations at very low doses can be achieved through superposition techniques to study periodic (Unwin & Henderson, 1975) and nonperiodic (Saxton & Frank, 1977) specimens. In addition, protection methods such as glucose embedding (Unwin & Henderson, 1975) and maintenance of specimen hydration at low temperatures (Taylor & Glaeser, 1976) have also shown promise. Despite these successes, the basic nature of radiation damage in the electron microscope is far from clear. In general we cannot predict exactly how different structures will behave during electron Irradiation at high dose rates. Moreover, with the rapid rise of analytical electron microscopy over the last few years, nvicroscopists are becoming concerned with questions of compositional as well as structural integrity. It is important to measure changes in elemental composition arising from atom migration in or loss from the specimen as a result of electron bombardment.

Decoration technique and surface physics

1978 ◽  
Vol 36 (1) ◽  
pp. 436-437 ◽  
Author(s):  
H. Bethge
Keyword(s):  
Diffusion Path ◽  
Special Importance ◽  
Surface Physics ◽  
Step Structure ◽  
Initial Stage ◽  
Special Cases ◽  
Atomic Surface ◽  
The Mean ◽  
Bulk Structure ◽  
Decoration Technique

Besides the atomic surface structure, diverging in special cases with respect to the bulk structure, the real structure of a surface Is determined by the step structure. Using the decoration technique /1/ it is possible to image step structures having step heights down to a single lattice plane distance electron-microscopically. For a number of problems the knowledge of the monatomic step structures is important, because numerous problems of surface physics are directly connected with processes taking place at these steps, e.g. crystal growth or evaporation, sorption and nucleatlon as initial stage of overgrowth of thin films.To demonstrate the decoration technique by means of evaporation of heavy metals Fig. 1 from our former investigations shows the monatomic step structure of an evaporated NaCI crystal. of special Importance Is the detection of the movement of steps during the growth or evaporation of a crystal. From the velocity of a step fundamental quantities for the molecular processes can be determined, e.g. the mean free diffusion path of molecules.

One Size Fits All?

Methodology ◽  
2012 ◽  
Vol 8 (1) ◽  
pp. 23-38 ◽  
Author(s):  
Manuel C. Voelkle ◽  
Patrick E. McKnight
Keyword(s):  
Repeated Measures ◽  
Structural Equation ◽  
Type I Error ◽  
Equation Modeling ◽  
Type I ◽  
Finite Sample ◽  
Traditional Methods ◽  
Repeated Measures Anova ◽  
Special Cases ◽  
Latent Curve

The use of latent curve models (LCMs) has increased almost exponentially during the last decade. Oftentimes, researchers regard LCM as a “new” method to analyze change with little attention paid to the fact that the technique was originally introduced as an “alternative to standard repeated measures ANOVA and first-order auto-regressive methods” (Meredith & Tisak, 1990, p. 107). In the first part of the paper, this close relationship is reviewed, and it is demonstrated how “traditional” methods, such as the repeated measures ANOVA, and MANOVA, can be formulated as LCMs. Given that latent curve modeling is essentially a large-sample technique, compared to “traditional” finite-sample approaches, the second part of the paper addresses the question to what degree the more flexible LCMs can actually replace some of the older tests by means of a Monte-Carlo simulation. In addition, a structural equation modeling alternative to Mauchly’s (1940) test of sphericity is explored. Although “traditional” methods may be expressed as special cases of more general LCMs, we found the equivalence holds only asymptotically. For practical purposes, however, no approach always outperformed the other alternatives in terms of power and type I error, so the best method to be used depends on the situation. We provide detailed recommendations of when to use which method.

Penile Fracture-Report of Two Cases and Review of Current Literature

KYAMC Journal ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 122-125
Author(s):  
Ashraf Uddin Mallik ◽  
Mostafizur Rahman ◽  
Fatema Bagum ◽  
Uttam Karmaker ◽  
Baikali Ferdous ◽  
...  
Keyword(s):  
Tunica Albuginea ◽  
Traumatic Rupture ◽  
Penile Fracture ◽  
Corpora Cavernosa ◽  
Effective Treatment Modality ◽  
Special Cases ◽  
History Of ◽  
Penile Injury ◽  
Urological Emergency ◽  
Erect Penis

Penile fracture is an uncommon urological emergency, especially in Bangladesh. The other name is traumatic rupture of the tunica albuginea and corpora cavernosa in the erect penis. It occurs when an erect penis face to buckle under the pressure of a blunt sexual trauma. Patient gives the typical history of immediate detumescence, severe pain, swelling and eggplant deformity of the penile shaft due to penile injury. Immediate surgical exploration and repair of corpora Cavernosa with tunica albugenia is the most effective treatment modality. In normal cases diagnosis is made from history, physical examination alone. In some special cases ultrasonogram, radiological images, including retrograde urethrography or cavernosography are mandatory for proper diagnosis. KYAMC Journal Vol. 10, No.-2, July 2019, Page 122-125

Computing Cores for Existential Rules with the Standard Chase and ASP

2020 ◽  
Author(s):  
Markus Krötzsch
Keyword(s):  
Large Class ◽  
Data Exchange ◽  
Answer Set Programming ◽  
Query Answering ◽  
Universal Model ◽  
The Core ◽  
Universal Models ◽  
General Terms ◽  
Special Cases ◽  
The Many

To reason with existential rules (a.k.a. tuple-generating dependencies), one often computes universal models. Among the many such models of different structure and cardinality, the core is arguably the “best”. Especially for finitely satisfiable theories, where the core is the unique smallest universal model, it has advantages in query answering, non-monotonic reasoning, and data exchange. Unfortunately, computing cores is difficult and not supported by most reasoners. We therefore propose ways of computing cores using practically implemented methods from rule reasoning and answer set programming. Our focus is on cases where the standard chase algorithm produces a core. We characterise this desirable situation in general terms that apply to a large class of cores, derive concrete approaches for decidable special cases, and generalise these approaches to non-monotonic extensions of existential rules.

CURRENT SITUATION OF MANAGEMENT AND USE OF TEACHING EQUIPMENT UNDER ORIENTATIONS FOR DEVELOPING STUDENT CAPACITY IN LOWER SECONDARY SCHOOLS IN DIEN BIEN DISTRICT, DIEN BIEN PROVINCE IN THE PRESENT PERIOD

2019 ◽  
Vol 8 (4) ◽  
Author(s):  
Pham Van Phuc ◽  
Ngo Quang Son
Keyword(s):  
Secondary Schools ◽  
Teaching Methods ◽  
Time Management ◽  
Current Trend ◽  
Equipment Management ◽  
Full Time ◽  
Special Cases ◽  
Effective Use ◽  
Lower Secondary Schools

Last time, management of equipment, maintenance and use of teaching equipment in lower secondary schools in Dien Bien district, Dien Bien province has been paid more attention, making important contributions to keeping sustainably, improve the quality of education in the district. Every year the lower secondary schools have been given funding and have plans to equip additional teaching equipment. Most lower secondary schools have full-time staff in charge of teaching equipment; with equipment storage rooms, cabinets are gradually added; laboratories and classrooms have been built more and more; have a system of records of teaching equipment management established; The work of inventorying and purifying teaching equipment periodically was also concerned. The movement of innovating teaching methods has made education managers and teachers more interested in using teaching equipment effectively. The positive management measures have caused many teachers to use teaching equipment as an integral part of the lesson, helping the quality of the lessons be increasingly improved to meet the requirements of changes. New teaching methods. Education administrators, teachers, teaching equipment staff are becoming more and more serious in teaching device management. However, the reality of teaching equipment management still reveals many limitations: The management of teaching equipment in schools is still administrative and ineffective. The equipment has no overall and detailed plans; The procurement of teaching equipment is not guaranteed in terms of quantity, lack of uniformity (some are redundant, some are lacking), quality is limited (durability, accuracy is not guaranteed, some new ones are not used); preservation still has many shortcomings; lack of specialized staff; lack of storage space or insufficient storage; lack of cabinets, prices, laboratories, subject classrooms; specially managing the use of teaching equipment is not tight; Many places teachers have not paid attention to use, ineffective use. The situation of “teaching vegetarianism” is still common, teaching equipment used is still movement, mostly used only in special cases such as competitions for good teachers, lectures or when there is a delegation check; There are many cases of information technology abuse in teaching. The effective use of teaching equipment oriented student capacity development is not much. The management of the use of teaching equipment oriented to develop student competencies in the current trend of Industry Revolution 4.0 is a matter of great concern to educational managers.Thus, the task of surveying the situation of managing the effective use of teaching equipment, finding subjective and objective reasons in order to propose measures to effectively manage the use of teaching equipment in the direction of developing students’ practical capacities and contributing to improving the quality of teaching in secondary schools in Dien Bien district, Dien Bien province is a very important and necessary task today.

Compiler-Aided Run-Time Performance Speed-Up in Super-Scalar Processor

10.28945/3391 ◽  
2009 ◽  
Author(s):  
Moshe Pelleh
Keyword(s):  
Embedded Systems ◽  
Embedded System ◽  
General Purpose ◽  
Experimental Results ◽  
Medium Size ◽  
Organic System ◽  
Software Application ◽  
Organic Systems ◽  
Special Cases ◽  
Run Time

In our world, where most systems become embedded systems, the approach of designing embedded systems is still frequently similar to the approach of designing organic systems (or not embedded systems). An organic system, like a personal computer or a work station, must be able to run any task submitted to it at any time (with certain constrains depending on the machine). Consequently, it must have a sophisticated general purpose Operating System (OS) to schedule, dispatch, maintain and monitor the tasks and assist them in special cases (particularly communication and synchronization between them and with external devices). These OSs require an overhead on the memory, on the cache and on the run time. Moreover, generally they are task oriented rather than machine oriented; therefore the processor's throughput is penalized. On the other hand, an embedded system, like an Anti-lock Braking System (ABS), executes always the same software application. Frequently it is a small or medium size system, or made up of several such systems. Many small or medium size embedded systems, with limited number of tasks, can be scheduled by our proposed hardware architecture, based on the Motorola 500MHz MPC7410 processor, enhancing its throughput and avoiding the software OS overhead, complexity, maintenance and price. Encouraged by our experimental results, we shall develop a compiler to assist our method. In the meantime we will present here our proposal and the experimental results.

The Study of ESD Destructive Mechanism for PN-Junction

1996 ◽  
Author(s):  
N. Wakai ◽  
M. TsuTsumi ◽  
T. Setoya
Keyword(s):  
Energy Density ◽  
Thermal Diffusion ◽  
Electric Discharge ◽  
Intermediate Region ◽  
Human Body Model ◽  
Machine Model ◽  
Pn Junction ◽  
Special Cases ◽  
Equilibrium Region

Abstract Mechanism of destruction caused by electrostatic discharge of PN junction was examined from two viewpoints; classification of destruction mode with consideration to destructive energy density, and comparison of destruction shape. Destructive energy density of PN junction was calculated based on Speakman model, and destruction mode was classified by Wunsch-Bell plot. As a result of Wunsch-Bell plot, electric discharge which occur at low resistance, for example machine model (MM: C∙R = 200pF ∙ 0Ω), resulted in adiabatic destruction that does not involve thermal diffusion. With electric discharge at high resistance, for example human body model (HBM: C∙R = 100pF ∙ 1500Ω), excessive destruction in intermediate region that involves thermal diffusion, and depending on the device, destruction at equilibrium region were proven to be reproducible. In case of MM, (adiabatic region destruction) destruction was confirmed in a wide extent of the joint part, but in case of HBM (intermediate region destruction) destruction was confirmed near the center of the joint part. From this fact, it was found that by verifying the places of destruction and their shapes, although in special cases, it is possible to know the destruction mode when destruction occurs.

Special Cases of the Decision Problem

1951 ◽  
Vol 49 (22) ◽  
pp. 203-221 ◽  
Author(s):  
Alonzo Church
Keyword(s):  
Decision Problem ◽  
Special Cases
Sign in / Sign up

Export Citation Format

Share Document