National Puzzler\u27s League

You probably noticed that some authors of anagrams use pseudonyms. Most of them are members of the National Puzzlers League (NPL), an Americna non-profit organization focused on puzzling, primarily in the realm of word play and word games. Founded in 1883, NPL is the oldest puzzlers\u27 organization in the world. it originally hosted semiannual conventions in February and September of each year, but conventions are now held annually, in July

Mobility engineering and metal-insulator transition in monolayer MoS2

Two-dimensional (2D) materials are a new class of materials with interesting physical properties and ranging from nanoelectronics to sensing and photonics. In addition to graphene, the most studied 2D material, monolayers of other layered materials such as semiconducting dichalcogenides MoS2 or WSe2 are gaining in importance as promising insulators and channel materials for field-effect transistors (FETs). The presence of a direct band gap in monolayer MoS2 due to quantum mechanical confinement, allows room-temperature field-effect transistors with an on/off ratio exceeding 108. The presence of high-k dielectrics in these devices enhanced their mobility, but the mechanisms are not well understood. Here, we report on electrical transport measurements on MoS2 FETs in different dielectric configurations. Mobility dependence on temperature shows clear evidence of the strong suppression of charge impurity scattering in dual-gate devices with a top-gate dielectric together with phonon scattering that shows a weaker than expected temperature dependence. High levels of doping achieved in dual-gate devices also allow the observation of a metal-insulator transition in monolayer MoS2. Our work opens up the way to further improvements in 2D semiconductor performance and introduces MoS2 as an interesting system for studying correlation effects in mesoscopic systems.Comment: Submitted January 11, 201

Small-signal amplifier based on single-layer MoS2

In this Letter we demonstrate the operation of an analog small-signal amplifier based on single-layer MoS2, a semiconducting analogue of graphene. Our device consists of two transistors integrated on the same piece of single-layer MoS2. The high intrinsic band gap of 1.8 eV allows MoS2-based amplifiers to operate with a room temperature gain of 4. The amplifier operation is demonstrated for the frequencies of input signal up to 2 kHz preserving the gain higher than 1. Our work shows that MoS2 can effectively amplify signals and that it could be used for advanced analog circuits based on two-dimensional materials.Comment: Submitted version of the manuscrip

620 7x7 Squares WIth Geographical Palindromes

It is not easy to make a 7x7 palindromic square with common words as nouns, adjectives, verbs, etc. In Serbia, puzzlers have made 10-15 such squares, all with some unusual terms like the title of a book, or the name of a person or geographical place. With the help of atlases and the Internet, we can make even some thematic palindrome squares. Most of these interesting places I found on the Dan Tilque site

Letter Banks

A letter bank is a type of puzzle where all the letters of one word (the bank ) can be used as many times as desired (a minimum of once each) to make a new word or phrase. For example, IMPS is a bank of MISSISSIPPI, and CYNDI LAUPER is a letter bank of PERPENDICULARLY

Dynamics of eye movements under time varying stimuli

In this paper we study the pure-slow and pure-fast dynamics of the disparity convergence of the eye movements second-order linear dynamic mathematical model under time varying stimuli. Performing simulation of the isolated pure-slow and pure-fast dynamics, it has been observed that the pure-fast component corresponding to the eye angular velocity displays abrupt and very fast changes in a very broad range of values. The result obtained is specific for the considered second-order mathematical model that does not include any saturation elements nor time-delay elements. The importance of presented results is in their mathematical simplicity and exactness. More complex mathematical models can be built starting with the presented pure-slow and pure-fast first-order models by appropriately adding saturation and time-delay elements independently to the identified isolated pure-slow and pure-fast first-order models

Numerograms - Another Hidden Meanings in Letters

Numerogram is a puzzle which I invented in 2001. It was firstly published in Belgrade magazine Enigmatika

EXPERIMENTAL AND NUMERICAL INVESTIGATION ON THE PERFORMANCES OF A SMALL WEAPON BARREL DURING ITS LIFECYCLE

The paper presents experimental and numerical investigations on the performances of a small caliber rifle barrel during its lifecycle. Two 7.62 mm rifle barrels were used, the first was considered as a standard barrel, the second barrel was subjected to an accelerated life cycle test. Measurements of the muzzle velocity, the rate of fire and the firearm accuracy and precision were carried out. The paper presents the correlation between the measured parameters and the total number of shots fired. After the durability tests, longitudinal cross sections were made by cutting the tested and the standard barrels. 3D scanning was employed to perform a comparison between the tested and the standard bore surfaces. ANSYS Explicit dynamic analyses were performed based on the obtained surface scans. The numerical analyses results of the tested and the standard barrels showed good agreement with the experimental and the numerical internal ballistic model results

Charge photogeneration in few-layer MoS2

The two-dimensional semiconductor MoS2 in its mono- and few-layer form is expected to have a significant exciton binding energy of several 100 meV, leading to the consensus that excitons are the primary photoexcited species. Nevertheless, even single layers show a strong photovoltaic effect and work as the active material in high sensitivity photodetectors, thus indicating efficient charge carrier photogeneration (CPG). Here we use continuous wave photomodulation spectroscopy to identify the optical signature of long-lived charge carriers and femtosecond pump-probe spectroscopy to follow the CPG dynamics. We find that intitial photoexcitation yields a branching between excitons and charge carriers, followed by excitation energy dependent hot exciton dissociation as an additional CPG mechanism. Based on these findings, we make simple suggestions for the design of more efficient MoS2 photovoltaic and photodetector devices