Earticle

By developing molds and facilities to horizontally mold the functional part of the dry-cast concrete block, We intend to develop molds and a series of facilities to horizontally mold the functional part of the dry-cast concrete block to increase production per cycle while maintaining existing production methods and major facilities. In order to do so, CAE analysis is first required to develop molds and facilities for horizontally molding the functional part of the drycast concrete block in the horizontal direction. The procedure will be carried out by reviewing the validity of boundary conditions and physical properties, 3D modeling, grid generation, construction of analysis models, model validity, analysis according to frequency changes, and analysis according to physical properties. First, through the comparison of two-point support, three-point support, and two-point and three-point support in the constraint conditions, We would like to compare it with the actual molded product in the horizontal direction.

By developing molds and facilities to horizontally mold the functional part of the dry-cast concrete block, We intend to develop molds and a series of facilities to horizontally mold the functional part of the dry-cast concrete block to increase production per cycle while maintaining existing production methods and major facilities. In order to do so, CAE analysis is first required to develop molds and facilities for horizontally molding the functional part of the drycast concrete block in the horizontal direction. The procedure will be carried out by reviewing the validity of boundary conditions and physical properties, 3D modeling, grid generation, construction of analysis models, model validity, analysis according to frequency changes, and analysis according to physical properties. First, through the comparison of two-point support, three-point support, and two-point and three-point support in the constraint conditions, We would like to compare it with the actual molded product in the horizontal direction. But first of all, it is considered three-point support in the constraint conditions in this paper.

By developing molds and facilities to horizontally mold the functional part of the dry-cast concrete block, We intend to develop molds and a series of facilities to horizontally mold the functional part of the dry-cast concrete block to increase production per cycle while maintaining existing production methods and major facilities. In order to do so, CAE analysis is first required to develop molds and facilities for horizontally molding the functional part of the drycast concrete block in the horizontal direction. The procedure will be carried out by reviewing the validity of boundary conditions and physical properties, 3D modeling, grid generation, construction of analysis models, model validity, analysis according to frequency changes, and analysis according to physical properties. First, through the comparison of two-point support, three-point support, and two-point and three-point support in the constraint conditions, We would like to compare it with the actual molded product in the horizontal direction. But first of all, it is considered two-point support in the constraint conditions in this paper.

This study aim to evaluates the urban form Type of Kang Buk and Kang Nam formed as the central urban area in 1970-80s to compares and analyze how corresponds to the City Problem. Mugyo-dong°§Da-dong°Øs Block of C.B.D in Kang-Buk and Yeoksam-dong°Øs Block of sub C.B.D in Kang-Nam are selected as comparative area. The comparative criteria drawn by the result of the Urban Doughnut Phenomena, the Reduction of Vitality of in Street Space and the urban planning factor which is analyzable are set. Two types of the urban form were compared and the results are as follows. Mugyo-dong°§Da-dong°Øs Block has vulnerable structure about the Urban Problem for this reason. For examples, the decline of the diversity and the absence of the residential function, the uniform arrangement of the road, the internal block consisting of the large lot, the discontinuous street space, the insufficient activation Use and the building°Øs entrances. On the other hand Yeoksam-dong°Øs Block has adaptable structure about the Urban Problem. For examples, the mixed Land Use and function, the various pattern of the network, the internal block consisting of the small lots, the continuous and organic street space, the various Use and the building°Øs elevation. This research result shows that urban form gives the very important effect in the function and role of the central urban area.

연안재해 저감을 위한 정부 사업 중 연안침식 및 퇴적을 저감시키기 위한 연안정비 사업 1단계(2000년~2009 년)와 2단계(2010년~2019년)가 현재까지 진행중이다. 이와 같은 연안정비 사업을 수행함에 있어 연안 보호를 위한 인공 콘크리트 피복재의 설치가 필요하다. 현재 국내에서는 일본에서 개발된 제품을 현장에 적용하고 있거나, 호안보 호공 설치를 시행하는 건설사에서 자체 개발한 블록을 설치하고 있는 추세이다. 그렇지만 이에 대한 수리특성 검증 및 안정성확보 여부, 설계기법과 같은 기술적인 검토는 부족한 상황이다. 본 연구에서는 이런 점들을 보완하여 사람 들의 접근성이 좋으면서 연안재해 저감 및 보호 능력이 우수한 친수형 호안 블럭을 개발하고자 한다. 본 연구를 통 하여 호안블록의 수리특성 및 안정계수를 도출할 수 있었다.

Among government projects for reduction of coastal disaster, coastal maintenance project stage 1(2000~2009) and stage 2(2010~2019) to reduce coastal erosion and sedimentation are currently under process. In performing the coastal maintenance projects, it is necessary to install artificial concrete armor units for coastal protection. Presently in Korea, products manufactured in Japan are applied to the site, or blocks self-developed by the construction firms are installed. However, there is a lack of technical reviews such as verification of hydraulic characteristics, securing the stability and design techniques. This study is intended to develop waterfront shore protection blocks with good accessibility of people and excellent coastal disaster reduction and protection capability. Through this study, hydraulic characteristics and stability coefficients of shore protection blocks could be drawn.

연구목적: 본 연구는 보행자의 안전 및 다양한 정보를 제공할 수 있는 바닥용 콘크리트 공공 사인 블록 의 개발을 목적으로 한다. 연구방법: 이러한 연구목적을 달성하기 위하여 위하여 공공 사인 블록 개발과 관련하여 적용한 단계별 블록 제작 기술을 제시하고, 개발된 콘크리트 공공 사인 블록의 현장적용성을 평가하였다. 연구결과: 본 연구에서 개발된 바닥용 콘크리트 공공 사인 블록은 다양한 형상의 공공 사인 의 표현이 가능하고, 제조 단가를 절감할 수 있을 것으로 보인다. 2년간의 사용성 평가결과 균열, 모서리 탈락, 변색, 마모 등의 문제는 발견되지 않아 충분한 내구성을 확보한 것으로 판단된다. 결론: 이러한 연 구 결과를 토대로 콘크리트 공공 사인 블록이 기존의 바닥용 공공 사인에 활용되어 오던 스티커, 석재 및 황동판 등의 취약점을 보안할 수 있는 대안으로 활용될 것으로 보이며, 향 후 블록 디자인의 다양화 를 도모하여 여러 분야에 적용될 수 있기를 기대한다.

Purpose: The purpose of this study is to develop a concrete public sign block for floors that can provide pedestrian safety and various information. Method: In order to achieve these research objectives, step-by-step block manufacturing techniques applied in relation to the development of public sign blocks were proposed, and the field applicability of the developed concrete public sign blocks was evaluated. Result: The concrete public sign block for floors developed in this study is expected to be capable of expressing public signs of various shapes and to reduce manufacturing cost. As a result of the usability evaluation for two years, no problems such as cracks, edge dropouts, discoloration, and abrasion were found, so it is judged that sufficient durability was secured. Conclusion: Based on these research results, it is expected that the concrete public sign block will be used as an alternative to secure the weaknesses such as stickers, stone and brass plates that have

영상의학과에는 다양한 질병을 가진 환자들이 검사를 받는 곳으로 병원감염의 교차 오염이 될 가능성이 큰 부서 이다. 특히 자기공명영상(MRI)검사는 다른 검사에 비해 검사시간이 오래 걸려 교차오염에 더욱더 노출이 될 수 있다. 이에 본 연구는 MRI검사장비의 소독실태를 파악하고, 환자와 접촉이 가장 많은 Head coil, 환자 고정용 Block, 밀폐된 공간인 Bore에서의 세균분포도를 파악 하였다. MRI 검사장비의 소독실태는 MRI실 근무자 150명을 대상으로 설문을 실시하였으며, 세균분포의 파악은 10 곳의 의료기관에서 측정하였다. MRI 장비의 세균 분포도결과 Staphylococcus, 등의 다양한 세균들이 발견되었다. MRI실 소독실태 파악결과 Head coil, Block, Bore의 소독은 잘 시행되는 것으로 나타났으며, 소독의 시기는 아 침에 1회 소독을 가장 많이 시행 하는 것으로 나타났다. 또한 감염관리자에 따른 소독의 유,무 와 소독의 시기에서는 MRI 실 검사자가 감염관리 할 때 잘 시행되는 것으로 나타났다. 환자를 검사한 후 교차오염을 방지하기 위하여 바로 적절한 소독제로 소독을 실시하여 교차오염을 방지하여야 할 것이다.

In radiology department, where patients with a variety of diseases receive their tests, there is a large possibility of cross contamination of nosocomial infection. Magnetic resonance imaging (MRI) tests take particularly more time than other tests do, which increases the possibility of being exposed to cross contamination. Therefore, this research examines the status of MRI equipment sterilization and investigates the bacterial distribution on head coils, which have the most frequent contact with patients, patient fixation blocks, and bores, which are confined spaces. The status of MRI equipment disinfection was examined by a survey targeting 150 employees, and the distribution of bacteria was measured in ten medical facilities. The result of bacterial distribution tests on MRI equipment showed various bacteria, including Staphylococcus, Acinetobacter, Sphingomona, Pantoea agglomeranss, Micrococcus, Bacillus, Saprophyticus, Brevundimona, and Myroidesspecies. The result of examining the stat us of MRI room disinfection showed that the disinfections of the head coil, block, and bore were implemented well, and the largest proportion was carried out once a day in the morning. The time and implementation of disinfection by the disinfection manager showed that they were implemented well when the manager was the MRI room examiner. The disinfection after examining a patient using an appropriate disinfectant is mandatory to prevent cross contamination.

The purpose of this study is to find the non-residental use diversion in residental area has any definite rules in terms of urban space by analyzing the Planned Exclusive Residental Area in Changwon City that has been developed as new town around an national industrial estate. By the analysis, with reference to location characteristics by uses, blocks connected to the main street and commercial road, and street sides with high integration value showed high ratio of location for shopping products, while blocks connected to branch streets with low integration value showed high distribution of business facilities. Blocks with exclusive and specialized commercial facilities, however showed high distribution of the specialized use, regardless of types of connecter streets and intergration value.

일축압축강도는 암반공학에서 가장 중요하고 널리 사용되는 암석의 역학적 특성중 하나이다. 표준시험법에서 제안한 규격에 적합한 암석 시험편을 필요로 한다. 그러나 균열이 많거나 절리 간격이 매우 조밀하게 성된 암반에서는 시험에 필요한 암석 코어를 쉽게 획득하지 못하는 경우가 있다. 따라서 본 연구에서는 상대적로 얇은 두께의 시험편을 이용하는 Block punch strength index(BPI) 시험을 통해 암석의 일축압축강도와 압열인장강도를 추정할 수 있는 관계식을 도출하였다. 또한, 점하중 시험, 슈미트 해머시험의 결과와 비교하여 BPI 험을 통한 암석의 강도추정의 타당성을 검증하였다.

Uniaxial compressive strength (UCS) is one of the most important and widely used rock mechanical properties in rock engineering. Good quality specimen which is recommended in standard UCS test, however, can not be easily obtained from densely fractured or thinly bedded rock masses. In this study, the UCS and the Brazilian tensile test (BTS) have been estimated by their relations to the block punch strength index (BPI), in which a relatively thin specimen is used. Also, the validity of strength prediction based on BPI test was secured through comparison with the results of point load strength index test and schmidt hammer test.

본 연구는 현재 다양한 신경심리 배터리에 포함되어 알츠하이머형 치매의 진단에 사용되고 있는 Corsi Block Test(CBT)의 유용성을 검증하기 위해 진행되었다. 이를 위해 MMSE 10점 이상의 알츠하이머형 치매 환자 20명을 대상으로 CBT와 신경심리학적 검사를 함께 실시하여 정상노인 55명의 수행 결과와 비교하였다. 연구 결과 알츠하이머형 치매 환자의 CBT 수행은 정상노인집단에 비해 유의미하게 저조한 것으로 나타나 현재 치매 감별 및 치매 연구에 널리 사용되는 숫자 바로 외우기와 거꾸로 외우기, K-DRS, S-K-BNT, K-CVLT의 장기지연 자유회상 등의 신경심리학적 검사와 마찬가지로 CBT 역시 두 집단 간 차이를 확인할 수 있는 도구로 나타났다. 그러나 이상의 모든 신경심리검사 및 CBT의 로지스틱 회귀 분석 결과 기존의 신경심리검사 중 K-CVLT와 K-BNT만이 치매집단과 정상노인 집단 간 변별에 유의미한 기여를 하는 것으로 나타났으며, CBT를 추가하여도 이들의 변별능력은 증가하지 않았다. 마지막으로 본 연구의 의의와 제한점, 후속 연구에 대한 시사점이 논의되었다.

The purpose of the present study was to investigate the visual-spatial working memory deficits in Alzheimer's disease patient(AD), compared to normal elderly(NE), using the Corsi block test(CBT), and to examine its clinical usefulness as neuropsychological method in the test battery for Alzheimer's patients. CBT and neuropsychological tests were administered to 20 AD patients with 20 or more MMSE scores and 55 normal elderly adults(NE). The results showed that significant mean value differences were revealed between AD and NE groups in the Digit Span(forward and backward), K-DRS, S-K-BNT, long-term delayed free recall of K-CVLT scores. Also CBT score differences were present. But as the results of the logistic regression analysis, even though the CBT was added to the other diagnostic tests for AD as K-CVLT or K-BNT, the discriminatory power of CBT fell into insignificant. Finally, the results were discussed and the implications for future studies were suggested.

With recent trends, the cloud-computing paradigm has gained significant attention, especially in patient health monitoring applications. To date, several cryptographic methods have been introduced to accomplish secure medical data access and storage in cloud service providers. However, these methods have failed to strike a balance among the demands of Electronic Health Records (EHRs) security solutions. Blockchain-based technology is a practical option for managing individual EHRs, as it offers an advanced solution for enhancing the privacy and security of medical data. Therefore, this research proposes a hybrid cryptographic algorithm: Secure Hash Algorithm-256 (SHA-256) combined with Composite Logistic Sine Map (CLSM), namely SHACLSM, with Proxy Re-Encryption (PRE). Overall, the effectiveness of the proposed SHACLSM is analyzed in terms of scalability, computational delay, latency, transaction time, hash verification time, and hash generation time. The outcomes clearly indicate that the proposed SHACLSM-PRE cryptographic algorithm requires minimal transaction time, latency, hash generation time, and hash verification time when evaluated against conventional algorithms, namely Advanced Encryption Standard (AES), SHA-256, Elliptic Curve Cryptography (ECC), Rivest-Shamir-Adleman (RSA), and AES New Instructions (AES-NI).

Hospital costing has generally been using ABC costing method. However, based on increase of expensive equipment, the fixed cost is increased in the hospital industry. The most common equipment industry are using building block costing method for depreciation and equipment management costing elements. Additionally it presents three options that may be considered to be supported by the IT system to find the most appropriate alternative.

병원원가란 병원에서 진료, 수술, 교육 및 연구에 소비된 재화와 용역의 가치를 화 폐액으로 표시한 것으로 원가정보는 원가항목별로 표시되어 관리자와 경영자에게 제 공되어야 한다. 이러한 병원원가는 예산수립, 투자의사 결정 및 성과평가 등 내부 경 영관리를 위한 목적으로 유용한 정보를 제공해야 하고 외부적으로는 적절한 의료수가 결정의 기초자료로 활용될 수 있다. 그러나, 우리나라의 주요 병원에서 운영 중인 ABC 원가계산 방법은 병원원가 계산 의 거의 유일한 원가계산 방법 인정받고 있으며, 효과성이 우수함에도 불구하고 원가 계산 결과에 대한 신뢰성의 저하와 운영비용의 증가 등으로 인하여 활용도가 저조해 지고 경우에 따라서 폐기되는 사례도 발생하고 있다. 따라서 최근 병원에서 발생되는 비용의 구체적 특성과 병원의료 환경이 설비 의존형으로 변화됨에 따라 간접비가 증 가하고 있는 경영환경의 변화를 이해하여, 병원 원가계산 시스템의 발전적인 새로운 방식이 모색되어야 한다. 대안 중의 하나로 대표적인 장치산업의 하나인 통신업에서 사용되는 Building Block Costing 방식에 대한 적용 방식을 소개하고자 한다. Building Block Costing은 감가 상각비로 대표되는 자산관련 간접비와 설비와 시설 운영에 소요되는 인건비, 경비 등 의 비용을 ABC원가계산 방식과는 차별화된 원가계산 방식이다.

최근 무선통신의 발달로 인하여 음성 서비스 이외의 동영상, 인터넷 서비스와 같은 보다 큰 전송률을 요구하는 다양한 서비스 요구가 급속도로 높아지고 있다. 고속 전송률 서비스를 낮은 가격으로 많은 사용자에게 제공하기 위해 제한된 통신자원을 이용하여 보다 많은 데이터를 전송할 수 있는 물리계층 기술이 필요하게 되어 직교 주파수 다중 방식인 OFDM(Orthogonal Frequency Division Multiplexing)과 다수의 송 수신 안테나를 이용하는MIMO(Multiple Input Multiple Output)시스템을 사용하게 되었다. MIMO 기술 중 Spatial Multiplexing은 전송용량 이득은 가질 수 있지만, 다수의 안테나로 인한 상관으로 인해 Diversity gain을 얻지 못하는 단점을 가지고 있다. 본 논문에서는 차세대 전송기술로 부각되고 있는 고속의 무선 데이터 전송기술 내에서, MIMO-OFDM 시스템인 SDM방식에서 Diversity gain을 얻고자 제안된 Multi-Block을 이용한 SDM의 성능에 대해 알아보고, 앞으로의 연구 방향에 대해 설명하고자 한다.

Improving the transmission rates of multi-media delivery, such as moving pictures and internet services, has become increasingly important in modern society. To satisfy such high data rate requirements, the MIMO technique, which has the capacity to transmit large amounts of data using limited frequency resources, was developed. The Space Division Multiplexing (SDM) system is one of the MIMO techniques to be able to improve the transmission capacity. However, it is unable to achieve diversity gain because of interference due to the use of multiple antennas. In this paper, an SDM system that utilizes a Multi-Block method as an advanced transmission technique in a wireless communication system to obtain diversity gain is proposed and discussed fur the performance of the proposed system.

Block timing synchronization, which could be data-aided or non-data-aided, is a critical part of space?time block codes (STBCs) for recovery of transmitted symbols. The data-aided schemes are not suited for some problems like bandwidth efficiency and most of the existing non-data-aided techniques rely on the received signals statistics and channel coefficients estimation increasing their complexity. In this paper, a non-data-aided cyclostationary-based approach is proposed for block timing estimation in Alamouti STBC employing frequency-shifted versions of the received signals. The method is non-statistical with low complexity and requires no knowledge of channel coefficients. Simulation results confirm the effectiveness of the method.

RF 기반 고속 무선통신 기술이 급속히 발전함에 따라 무선 주파수 대역을 기반으로한 IoT 네트워크용 디바이스가 빠르게 보급되고 있으나, 최근 IoT 네트워크 디바이스의 급속한 확산 속도에 비하여 RF 통신 기술의 발전속도가 미치지 못하고 있다. 이러한 상황에서 가시광원을 송신수단으로 사용하는 OWC 기술은 RF 기반 무선 통신의 대역 고갈 문제를 극복 할 수 있는 기술로서 주목받고 있으나, OWC용 데이터 수신 중 발생하는 LED 조명 형태의 왜곡으로 인하 여 LED 조명 검출율이 저하되고 RoI의 설정이 부정확해지는 현상이 발생 할 가능성이 있다. 본 논문에서는 Adaptive Median Filter를 적용한 저속 카메라 통신용 LED 조명 검출 알고리즘을 제안하였다. 이를 통해 명확한 RoI 설정 및 LED 조명 검출이 가능할 것으로 사료되며, 본 연구 결과를 통해 RF 기반 무선 통신기술의 보완재로서의 역할을 효율적으로 수행 할 수 있을 것으로 판단된다.

With the rapid development of RF based high speed wireless communication technology, devices that can be applied to IoT networks based on RF bandwidth are rapidly spreading, nevertheless, the development speed of the RF communication is not possible to keep up with the spread of the RF band for wireless communication. In this situation, OWC technology that uses visible light source as a transmitter is attracting attention as a technology that can overcome the band exhaustion problem of RF based wireless communication technology. Although, due to the distortion of the LED illumination shape by camera exposure time and LED blinking period, the LED illumination detection rate is degraded and the RoI setting is inaccurate. In this paper, we propose an adaptive median filter applied LED illumination detection algorithm for low rate CamCom, it is possible to detect a clear RoI and LED illumination. This research will be able to play a role as a complementary material of RF based wireless communication technology efficiently.

In this letter, we propose space?time block coded non-orthogonal multiple access (STBC-NOMA) for underwater acoustic sensor networks (UASNs) to improve reliability by exploiting transmit diversity and spectral efficiency. We derive mathematical expressions for ergodic rate, outage probability and energy efficiency. Results show that STBC-NOMA can combine the advantages of STBCs and NOMA, which significantly enhance the performance of UASNs, without the need for prior CSI status at the transmitter. Finally, we jointly optimize the signal frequency and power allocation coefficient for the STBC-NOMA scheme with respect to the transmission distance using pattern search algorithm, to further enhance the ergodic rate.

Thenar motor neuropathy is a rare, pure motor neuropathy of the median nerve with delayed motor latency in electrophysiological studies. We present an extremely rare case of idiopathic thenar motor neuropathy with complete median motor conduction block at the carpal tunnel level, which was confirmed by ultrasonographic and surgical findings. Right median nerve conduction studies demonstrated normal sensory responses and no motor response in the abductor pollicis brevis (APB). Needle electromyography of the right APB showed no recruitment of motor unit action potentials. Ultrasonographic examination demonstrated enlarged and swollen median nerve fascicles within the carpal tunnel. A carpal tunnel release operation was performed; the median nerve underneath the transverse carpal ligament was swollen and blanched due to decreased vascularity, suggesting the presence of compression. Pain in the thenar area improved 2 weeks after surgery. Herein, we emphasize the usefulness of ultrasonographic evaluations in determining the level of the nerve injury in cases with doubtful electrophysiological results.