Abstract: A semiconductor memory device includes a memory cell array, a row decoder, a plurality of page buffers, and a voltage switching circuit. The memory cell array includes a plurality of memory cells. The row decoder is connected to the memory cell array through word lines. The plurality of page buffers are connected to the memory cell array through bit lines. The voltage switching circuit decodes an operation voltage and transmits the decoded operation voltage to the row decoder. The plurality of page buffers are formed in a first under cell region among first and second under cell regions, the first and second under cell regions being adjacent to each other in a first direction under the memory cell array. At least a portion of the voltage switching circuit is formed in an under slim region that is adjacent to the first under cell region and the second under cell region in a second direction.

Abstract: A positive electrode active material for a lithium secondary battery has a mixture of microparticles having a predetermined average particle size (D50) and macroparticles having a larger average particle size (D50) than the microparticles. The microparticles have the average particle size (D50) of 1 to 10 ?m and are at least one selected from the group consisting of particles having a carbon material coating layer on all or part of a surface of primary macroparticles having an average particle size (D50) of 1 ?m or more, particles having a carbon material coating layer on all or part of a surface of secondary particles formed by agglomeration of the primary macroparticles, and a mixture thereof. The macroparticles are secondary particles having an average particle size (D50) of 5 to 20 ?m formed by agglomeration of primary microparticles having a smaller average particle size (D50) than the primary macroparticles.

Abstract: A wafer manufacturing method, an epitaxial wafer manufacturing method, and a wafer and epitaxial wafer manufactured thereby, are provided. The wafer manufacturing method enables the manufacture of a wafer with a low density of micropipe defects and minimum numbers of particles and scratches. The epitaxial wafer manufacturing method enables the manufacture of an epitaxial wafer that has low densities of defects such as downfall, triangular, and carrot defects, exhibits excellent device characteristics, and improves the yield of devices.

Abstract: A wafer manufacturing method, an epitaxial wafer manufacturing method, and a wafer and epitaxial wafer manufactured thereby, are provided. The wafer manufacturing method enables the manufacture of a wafer with a low density of micropipe defects and minimum numbers of particles and scratches. The epitaxial wafer manufacturing method enables the manufacture of an epitaxial wafer that has low densities of defects such as downfall, triangular, and carrot defects, exhibits excellent device characteristics, and improves the yield of devices.

Abstract: A hot and cold pack for breast treatment for pregnant women is provided. The hot and cold pack for breast treatment for pregnant women includes a cover including a through hole in a center thereof, through which a user's nipple passes, and having an annular shape of which a portion is open to adjust a size according to the size of a user's breast while wrapping and covering the user's breast, a thermal insulating material filled inside the cover, and a length adjustment unit provided in the open portion of the cover to connect both sides of the open cover, and adjusting the size of the cover.

Abstract: A method of dynamic control rod reactivity measurement for a reactor using a fission chamber as an out-of-reactor measuring instrument includes: maintaining the reactor in a critical state having a set output by inserting a reference control bank into a reactor core to a first depth; completely inserting the reference control bank into the reactor core from the first depth at a maximum allowable speed and immediately completely withdrawing the reference control bank from the reactor core at the maximum allowable speed, and measuring a first signal of the out-of-reactor measuring instrument from before the insertion of the reference control bank to after the withdrawal of the reference control bank; and determining static controllability of the reference control bank by adding residual controllability measurement value of the reactor to a first static reactivity of the reactor calculated using the first signal of the out-of-reactor measuring instrument.

Abstract: Disclosed is a method of producing Tc-99m by using nuclear resonance fluorescence. More specifically, and a method of preparing Tc-99m by using nuclear resonance fluorescence includes irradiating a ground-state Tc-99 nucleus with a photon beam, thereby causing a nuclear transmutation to proceed such that the nucleus excited to high energy and then undergoes a transition to Tc-99m.

Abstract: Disclosed is an apparatus for extracting multiple laser Compton scattering (“LCS”) photon beams using a laser Compton scattering reaction, the apparatus including: a linear accelerator for accelerating an electron beam; and an LCS gamma ray generation module including an LCS gamma ray generator for irradiating a target with an LCS gamma ray generated by emitting laser light to an electron beam released from the linear accelerator and a bending magnet for adjusting a direction of the electron beam passed through the LCS gamma ray generator, wherein at least two LCS gamma ray generation modules are sequentially arranged to form a closed loop together with the linear accelerator.

Abstract: Disclosed is an apparatus for extracting multiple laser Compton scattering photon (“LCS”) beams using a laser Compton scattering reaction, the apparatus including: a linear accelerator for accelerating an electron beam; and an LCS gamma ray generation module including an LCS gamma ray generator for irradiating a target with an LCS gamma ray generated by emitting laser light to an electron beam released from the linear accelerator and a bending magnet for adjusting a direction of the electron beam passed through the LCS gamma ray generator, wherein at least two LCS gamma ray generation modules are sequentially arranged to form a closed loop together with the linear accelerator.

Abstract: Disclosed is a method of producing Tc-99m by using nuclear resonance fluorescence. More specifically, the method of producing Tc-99m by using nuclear resonance fluorescence includes irradiating a ground-state Tc-99 nucleus with a photon beam, thereby causing a nuclear transmutation to proceed such that the nucleus is excited to high energy and then undergoes a transition to Tc-99m.