Kolen Co., Ltd.

Sungkyunkwan University

Korea University Research and Business Foundation

University-Industry Cooperation Group of Kyung Hee University

Hyundai Steel Company

Elcomtec Co., Ltd.

Samsung Sds Co., Ltd.

Se Jin Kim

Ji Eun Kim

Jae Hoon Cho

Chi Ho Ahn

Chan Goo Kang

Seong Hee Bae

Hyun Suk Jung

Jun Hong Noh

Kyung Mun Yeom

Tae Hyung Kim

Jun Ho Lee

Hwa Young Kim

Chi Hyung Ahn

Jun Ho Chung

Bom Son Lee

Jae Hyeong Cho

So Yeon Park

Gun Young Kim

Sun Myung Kang

Sung Youn Hwang

Se Hun Na

Jae-Hoon Cho

Kyoung Rok Lim

Chang Jae Park

The present disclosure discloses metal oxide nanoparticle ink, a method of preparing the same, a metal oxide nanoparticle thin film manufactured using the same, and a photoelectric device using the same. The method of preparing metal oxide nanoparticle ink according to an embodiment of the present disclosure includes a step of, using a ligand solution including a metal oxide and an organic ligand, synthesizing a first nanoparticle that is a metal oxide nanoparticle surrounded with the organic ligand; a step of preparing a dispersion solution by dispersing the first nanoparticle in a solvent; a step of preparing a second nanoparticle by mixing the dispersion solution and a pH-adjusted alcohol solvent and then performing ultrasonication treatment to remove the organic ligand surrounding the first nanoparticle; and a step of preparing metal oxide nanoparticle ink by dispersing the second nanoparticle in a dispersion solvent.

Metal oxide nanoparticle ink, method of preparing the same, metal oxide nanoparticle thin film manufactured using the same, and photoelectric device using the same

A steel reinforcing bar contains 0.06 wt % to 0.11 wt % carbon, more than 0 and not more than 0.25 wt % silicon, 0.8 wt % or more and less than 2.0 wt % manganese, more than 0 and not more than 0.01 wt % phosphorus, more than 0 and not more than 0.01 wt % sulfur, 0.01 to 0.03 wt % aluminum, 0.50 to 1.00 wt % nickel, 0.027 to 0.125 wt % molybdenum, more than 0 and not more than 0.25 wt % chromium, more than 0 and not more than 0.28 wt % copper, more than 0 and not more than 0.01 wt % nitrogen, and the remainder being iron and unavoidable impurities. The reinforcing bar has a surface layer and a core. The surface layer has a hardened layer of tempered martensite, and the core has a mixed structure of bainite, ferrite and pearlite.

Steel reinforcing bar and production method therefor

An optical lens system is disclosed. The optical lens system includes a first lens that has negative refractive power, a second lens that has positive refractive power, a third lens that has positive refractive power, a fourth lens that has refractive power, a fifth lens that has positive refractive power, a sixth lens that has negative refractive power, an aperture located between the second lens and the third lens, and conditional expressions of '&#x2212;1.4&#x3c;tan &#x3b8;/f&#x3c;&#x2212;1.1' and '4.0&#x3c;TTL/BFL&#x3c;6.0' are satisfied when &#x3b8; is an angle of view of the optical lens system in a diagonal direction, f is a focal length of the optical lens system, TTL is a distance on an optical axis from the object-side surface of the first lens to the sensor, and BFL is a distance on the optical axis from the sensor-side surface of the sixth lens to the sensor.

Optical lens system

Disclosed is a wireless power transmission system using a meta-structure transmission line capable of performing beam steering. The wireless power transmission device using a meta-structure transmission line capable of performing beam steering includes a beam steerer including a meta-structure transmission line constituted of a plurality of single cells; a controller configured to control an operation mode and beam scanning of the beam steerer; and a power supply configured to supply power to the beam steerer under control of the controller.

Wireless power transmission system using meta-structure transmission line capable of performing beam steering

A photographic lens optical system which includes five lenses sequentially arranged in a direction from an object to an image sensor is disclosed. A first lens may have a positive refractive power and an entrance surface convex toward the object. A second lens may have a negative refractive power and an exit surface concave toward the image sensor. A third lens may have a positive refractive power and a meniscus shape convex toward the image sensor. A fourth lens may have a negative refractive power and a meniscus shape convex toward the image sensor. A fifth lens may have a negative refractive power, and at least one of an entrance surface and an exit surface of the fifth lens may be aspheric. The system may satisfy the formula: | tan &#x3b8;|/f&#x3c;1.0, &#x3b8; denoting an angle of view of the system, and f denoting a focal length of the system.

Photographic lens optical system

A photographic lens optical system includes: a first lens having a positive refractive power and a meniscus shape convex toward an object side; a second lens having a negative refractive power and a meniscus shape convex toward the object side; a doublet lens having a positive refractive power and formed by combining a third lens and a fourth lens; a fifth lens having a positive refractive power and a double convex shape; and a sixth lens having a positive refractive power and a double convex shape. The first to sixth lenses are sequentially arranged in a direction from the object side to an image side, and the photographic lens optical system satisfies the following condition:1.5&#x3c;2&#x3c;1.7

A photographic lens optical system. The photographic lens optical system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens that are sequentially arranged in a direction from an object toward an image sensor. The first lens has a negative (&#x2212;) power, and the emission surface thereof may be convex toward the object. The second lens may have a positive (+) power, the third and fourth lenses have positive (+) powers, and the fifth lens has a negative (&#x2212;) power. Furthermore, the sixth lens is an aspherical lens having a positive (+) power.

An imaging lens system includes, sequentially from an object side to an image side: a first lens having a positive refractive power; a second lens having a negative refractive power; and a third lens having a positive refractive power or a negative refractive power, wherein a viewing angle &#x3b8; satisfies following condition,0.7&#x3c;|tan &#x3b8;|&#x3c;1.5.

Imaging lens system

First, second, third, and fourth lenses (in order from an object side) are arranged between the object and an image sensor where an image of the object is formed. The first lens may have a positive refractive power and both surfaces thereof may be convex. The second lens may have a negative refractive power and both surfaces thereof may be concave. The third lens may have a positive refractive power and have a meniscus shape that is convex toward the image sensor. The fourth lens may have a negative refractive power and at least one of an incident surface and an exit surface thereof may be an aspherical surface. A sagittal depth SAGof an incident surface of the second lens along an optical axis and a sagittal depth SAGof an exit surface of the second lens along the optical axis may satisfy Inequality|SAG1|&#x3e;|SAG2|.

An imaging lens system includes, sequentially from an object side to an image side: a first lens having a positive refractive power; a second lens having a negative refractive power; and a third lens having a negative refractive power, wherein a viewing angle &#x3b8; satisfies following condition,0.3&#x3c;|tan &#x3b8;|&#x3c;0.8.

First, second, third, and fourth lenses (in order from an object side) are arranged between the object and an image sensor where an image of the object is formed. The first lens may have a positive refractive power and may be a meniscus lens that is convex toward the object. The second lens may have a positive refractive power and may be a meniscus lens that is convex toward the image sensor. The third lens may have a positive refractive power and may be a meniscus lens that is convex toward the image sensor. At least one of an incident surface and an exit surface of the fourth lens may be an aspherical surface. The fourth lens may have a negative refractive power or a positive refractive power. A viewing angle &#x3b8; of the lens optical system may satisfy a conditional expression, 2.5&#x3c;|tan &#x3b8;|&#x3c;3.5.

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Seoul, South Korea

Se Jin Kim