Abstract: The present description relates to an olefin block copolymer with excellences in elasticity, heat resistance, and processability. The olefin block copolymer comprises a plurality of blocks or segments, each comprising an ethylene or propylene repeating unit and an ?-olefin repeating unit at different mole fractions. The olefin block copolymer comprises polymer chains containing 20 to 100 short-chain branches (SCBs) per 1,000 carbon atoms. A point where a first derivative of the number Y of the SCBs per 1,000 carbon atoms of each polymer chain with respect to the molecular weight X of the polymer chain is 0 exists between the minimum and maximum values of the molecular weight X.

Abstract: The present invention relates to an ethylene/1-hexene or ethylene/1-butene copolymer having excellent processibility. The ethylene/1-hexene or ethylene/1-butene copolymer according to the present invention has high molecular weight and wide molecular weight distribution, and thus excellent processibility, and has excellent environmental stress crack resistance, and thus, may be applied for a high inner pressure heating pipe, a mining pipe, or a large-diameter pipe, and the like.

Abstract: The present invention relates to a supported hybrid catalyst and a method for preparing an olefin based polymer using the same. The supported hybrid catalyst according to the present invention can be used in the preparation of an olefin-based polymer, and the olefin-based polymer prepared using the supported hybrid catalyst has excellent processability and mechanical properties and thus can be effectively used for the application of films or the like.

Abstract: This disclosure relates to a silica support for a metallocene catalyst used for olefin polymerization, a preparation method thereof, a metallocene catalyst using the same, and olefin polymer. Specifically, according to the present invention, a silica support used for preparing a metallocene supported catalyst is treated with a specific halogenized metal compound, thereby diversifying reaction sites to a cocatalyst when preparing a metallocene catalyst, and thus, the molecular weight distribution of produced olefin polymer may be much broadened and polymer having high molecular weight may be obtained compared to the existing support, even if the same metallocene catalyst is supported.

Abstract: A preparation method of a catalyst for polyolefin polymerization capable of polymerizing low-density polyethylene in a single reactor without separately injecting a comonomer to thereby prepare a final product with a low cost through a more simplified process, a catalyst obtained by the preparation method, and a preparation method of a polyolefin using the catalyst are provided.

Abstract: The present invention relates to a hybrid supported metallocene catalyst. More specifically, the present invention relates to a hybrid supported metallocene catalyst using two or more different types or more of metallocene compounds, among which one type of the metallocene compounds shows a high polymerization activity even when it is supported, and thus the catalyst has an excellent activity and can be utilized in the polymerization of olefinic polymers having ultra-high molecular weight. Based on the hybrid supported metallocene catalyst of the present invention, an olefinic polymer having high molecular weight and the desired physical property can be prepared.

Abstract: The present invention relates to a method for preparing a hybrid supported metallocene catalyst. More specifically, the present invention relates to a method for preparing a hybrid supported metallocene catalyst by using two or more different types of metallocene compounds. One type of the metallocene compounds shows a high polymerization activity even when it is supported, and thus the catalyst has an excellent activity and can be utilized in the polymerization of olefinic polymers having ultra-high molecular weight. Based on the hybrid supported metallocene catalyst obtained according to the preparation method of the present invention, an olefinic polymer having high molecular weight and the desired physical property can be prepared.

Abstract: This disclosure relates to a silica support for a metallocene catalyst used for olefin polymerization, a preparation method thereof, a metallocene catalyst using the same, and olefin polymer. Specifically, according to the present invention, a silica support used for preparing a metallocene supported catalyst is treated with a specific halogenized metal compound, thereby diversifying reaction sites to a cocatalyst when preparing a metallocene catalyst, and thus, the molecular weight distribution of produced olefin polymer may be much broadened and polymer having high molecular weight may be obtained compared to the existing support, even if the same metallocene catalyst is supported.

Abstract: The present invention relates to a novel metallocene compound, a catalyst composition including the same, and a method of preparing an olefinic polymer by using the same. The metallocene compound according to the present invention and the catalyst composition comprising the same can be used for producing olefinic polymers, have outstanding polymerizing ability, and can produce olefinic polymers of ultra high molecular weight. In particular, when the metallocene compound according to the present invention is employed, an olefinic polymer of ultra high molecular weight can be obtained because it shows high polymerization activity even when it is supported on a carrier and maintains high activity even in the presence of hydrogen because of its low hydrogen reactivity.

Abstract: The present invention relates to a novel metallocene compound, a catalyst composition including the same, and a method of preparing an olefinic polymer by using the same. The metallocene compound according to the present invention and the catalyst composition comprising the same can be used for producing olefinic polymers, have outstanding polymerizing ability, and can produce olefinic polymers of ultra high molecular weight. In particular, when the metallocene compound according to the present invention is employed, an olefinic polymer of ultra high molecular weight can be obtained because it shows high polymerization activity even when it is supported on a carrier and maintains high activity even in the presence of hydrogen because of its low hydrogen reactivity.

Abstract: A preparation method of a catalyst for polyolefin polymerization capable of polymerizing low-density polyethylene in a single reactor without separately injecting a comonomer to thereby prepare a final product with a low cost through a more simplified process, a catalyst obtained by the preparation method, and a preparation method of a polyolefin using the catalyst are provided.

Abstract: An apparatus for grinding a substrate is disclosed. In one aspect, the apparatus includes an inlet which receives a jig seated with a substrate including a curved surface, a grinding part grinding the substrate conveyed from the inlet, and a washing part washing the substrate conveyed from the grinding part. The grinding part includes a plurality of rollers, and each roller includes a concave portion and a convex portion which are adjacently disposed and a plurality of brushes.

Abstract: A polyolefin has 1) a density in the range of 0.93 to 0.97 g/cm3, 2) a BOCD (Broad Orthogonal Co-monomer Distribution) index defined by a given equation in the range of 1 to 5, and 3) a molecular weight distribution (weight average molecular weight/number average molecular weight) in the range of 4 to 10. A supported hybrid metallocene catalyst comprises a first metallocene compound represented by a first given formulae, a second metallocene compound represented by one of three given formulae, and a support.

Abstract: The present description relates to olefin block copolymers having excellent elasticity and processability in conjunction with enhanced heat resistance, and to a preparation method thereof. The olefin block copolymers comprise a plurality of blocks or segments that comprise ethylene or propylene repeating units and ?-olefin repeating units at different mole fractions from one another, wherein the block copolymer shows peaks at the 2? of 21.5±0.5° and 23.7±0.5° in a wide-angle x-ray diffraction (WAXD) pattern, and the peak ratio defined by (the peak area at 21.5±0.5°)/(the peak area at 23.7±0.5°) is no more than 3.0.

Abstract: Provided is a method for transmitting a transmission symbol in a transmitting device supporting a filter bank multi carrier (FBMC) scheme. The method includes generating a training symbol by including a training signal in at least one of an odd symbol and an even symbol constituting the training symbol; generating the transmission symbol by delay-overlapping the training symbol and at least one data symbol; and transmitting the transmission symbol.

Abstract: An apparatus for forming a glass, the apparatus including a lower mold and an upper mold is disclosed. The lower mold may be configured to support a central portion of a lower surface of the glass. The upper mold may be configured to make point contact with an edge portion of an upper surface of the glass. The upper mold may press the edge portion of the upper surface of the glass to form a rounded portion of the edge portion of the glass. An apparatus for forming a glass, the apparatus including: a lower mold configured to make point contact with an edge portion of a lower surface of the glass; and an upper mold configured to press an interior portion of the upper surface of the glass to form a rounded portion at the edge portion of the glass, is also disclosed.

Abstract: The present invention relates to a novel metallocene compound, a catalyst composition comprising the same, and to olefinic polymers produced using the same. The metallocene compound according to the present invention and the catalyst composition comprising the same can be used when producing olefinic polymers, have outstanding copolymerization properties, and can produce olefinic polymers of high molecular weight. In particular, when the metallocene compound according to the present invention is employed, highly heat resistant block copolymers can be produced, and olefinic polymers can be produced which have a high melting point (Tm) even if the comonomer content is increased when producing the olefinic polymer.

Abstract: The present invention relates to a method of receiving available channel information on K (K?2) numbers of locations by a first type station (STA) from a second type STA in a wireless communication system includes: receiving a channel availability query (CAQ) response message, wherein the CAQ response message includes a field of the numbers (K) of the locations and K numbers of available channel list fields configured with information on an available channel list for each of the K numbers of locations, from the second type STA, and performing a communication in a white space using an available channel included in an available channel list for a single location among the K numbers of locations, wherein the K numbers of available channel list fields are configured with a Map ID field and a field of N (N?1) numbers of available channels are repeated K times.

Abstract: This disclosure relates to a silica support for a metallocene catalyst used for olefin polymerization, a preparation method thereof, a metallocene catalyst using the same, and olefin polymer. Specifically, according to the present invention, a silica support used for preparing a metallocene supported catalyst is treated with a specific halogenized metal compound, thereby diversifying reaction sites to a cocatalyst when preparing a metallocene catalyst, and thus, the molecular weight distribution of produced olefin polymer may be much broadened and polymer having high molecular weight may be obtained compared to the existing support, even if the same metallocene catalyst is supported.

Abstract: A method and apparatus for allocating a frequency resource to each micro User Equipment (UE) in a hierarchical cellular mobile communication system are disclosed. The method includes acquiring information about traffic of each macro UE or a macro BS in a frequency resource allocated to the macro UE or the macro BS, first Signal-to-Noise Ratio (SNR) information about an SNR of a signal from the macro UE or the macro BS, measured at each micro UE and second SNR information about an SNR of a signal from the micro UE, measured at each micro BS, calculating throughput of the micro UE using the traffic information, the first SNR information and the second SNR information, determining a frequency resource to be allocated to the micro UE using information about the calculated throughput and allocating the determined frequency resource to the micro UE.