Earticle

[목적] 이 연구의 목적은 무게와 딤플수, 그리고 압축강도를 동일하게 통제하여 제작한 2-piece, 3-piece, 4-piece 골 프공의 구조차이가 스핀양과 비거리에 미치는 영향을 관찰하는데 있다. [방법] 본 연구에서 골프공은 2 piece, 코어 1개+커버 2개의 3 piece, 코어 2개+커버 1개의 3 piece, 그리고 코어 2개+커버 2개의 4 piece 골프공을 각 12개씩 제 작하였으며, Hitting Machine을 이용하여 아이언과 52도 웨지샷 스윙을 통해 골프공 구조에 따른 차이를 확인하였다. [결과] 52도 웨지로 70m 거리에서 하강각에서 유의한 차이가 나타났다(p<0.01). 9번 아이언으로 120m 거리에서 볼스 피드(Ball speed)에서 유의한 차이가 나타났다(p<0.01). 그리고 발사각(Ball launch angle)에서 유의한 차이가 나타났다 (p<0.01). 7번 아이언으로 140m 거리 볼스피드(Ball speed)에서 유의한 차이가 나타났다(p<0.01). 또한 발사각(Ball launch angle)에서 유의한 차이가 나타났다(p<0.01). 5번 아이언으로 160m 거리에서 볼스피드(Ball speed)에서 유의한 차이가 나타났다(p<0.01). [결론] 이와 같은 결과는 골프공의 구조 자체만으로 골프공의 비거리 또는 스핀량으로 이어 지는 골프공의 성능에 영향을 미칠 수 있는 독립적인 요소가 될 수 있다.

[Purpose] The purpose of this study was to observe the effect of the structural difference of two-piece, three-piece and four-piece golf balls on the spin rate and carry distance with the same weight, dimple and compression strength. [Method] In this study, 12 pieces of golf balls were made of 2 pieces, 1 core + 2 covers, 3 pieces, 2 cores + 3 covers, 1 piece, and 2 cores + 2 covers. By using the Hitting Machine, the iron and 52-degree wedge-shot swings were used to identify the golf ball structure. [Result] There was a significant difference in the descent angle at a distance of 70m with a 52 degree wedge (p <0.01). There was a significant difference in ball speed at 120m distance with 9 irons (p <0.01). And significant difference was shown in Ball launch angle (p <0.01). Also, there was a significant difference in ball speed at 140m distance with iron 7 (p <0.01). There was also a significant difference in the ball launch angle (p <0.01). Significant differences were found in ball speed at 160 m distance with 5 irons (p <0.01). [Conclusion] These results indicate that golf ball structure as pieces, could be a independent contributor for golf ball distance or spin rate and subsequently golf ball performance.

[목적] 이 연구의 목적은 드라이버샷과 52도 웨지샷에 따른 3층 구조의 골프공 중 단일커버와 이중코어로 구성된 골프공(DSB)과 이중커버와 단일코어로 구성된 골프공(SDB)의 차이를 알아보는데 있다 [방법] 드라이버샷은 80, 90, 100 mph 스윙 속도를 이용하였으며, 52도 웨지샷은 70 mph의 스윙속도에서 비교하였다. [결과] 80mph의 드라이 버 스윙시 두 볼에서 유의한 차이는 관찰되지 않았다. 80 mph와 대조적으로 90 mph 드라이버 스윙시 DSB에서 최대높이까지의 거리(p=0.005), 비행거리(p=0.001), 총비거리(p=0.027)가 높게 관찰되었으며, 100 mph 드라이버 스 윙시 SDB와 비교하여 스핀량(p=0.007), 최대높이(p=0.032), 비행거리(p=0.006), 비행시간(p=0.041)이 유의하게 높게 나타났다. 웨지샷의 경우 발사각(p<0.001), 백스핀량(p=0.001), 총스핀량(p=0.001), 높이(p<0.001), 그리고 하강각도 (p<0.001)에서 DSB와 SDB에서 유의한 차이가 나타났다. 또한 100 mph 스윙 스피드에서 DSB와 SDB간에 백스핀량 (p=0.007), 최대높이(p=0.032), 비행거리(p=0.006), 그리고 비행시간(p=0.041)의 유의한 차이가 나타났다. [결론] 이 결 과는 DSB 적용이 골퍼 또는 코치가 드라이버 거리 및 정확성의 향상을 위해 선택할 수 있는 요인임을 나타낸다.

[Purpose] This study aims to demonstrate how, in 3-piece golf balls, the structure difference between dual core with single cover (DSB) and single core with dual cover (SDB) balls can affect the performance of drive shots and 52 degree wedge shots. [Method] The differences between the two ball types were determined by conducting drive shots at 80, 90, and 100 mph swing speeds along with 52-degree wedge shots at 70 mph. [Result] No significant differences were observed between the two balls in the drive shot performance at 80 mph swing speed. In contrast to 80 mph, better performances in DSB were observed in the distance to maximal height (p=0.005), carry distance (p=0.001), and total distance (p=0.027) at 90 mph swing speed. At 90 mph, spin rate (p=0.007), maximal height (p=0.032), carry distance (p=0.006), and flight time (p=0.041) in DSB were observed better performance compare with SDB. Launch angle (p<0.001), back spin rate (p<0.001), total spin rate (p<0.001), height, and decent angle (p<0.001) at wedge test were significantly difference between DSB and SDB. The maximal height (p=0.032), backspin rate(p=0.007), carry distance(p=0.006), and flight time(p=0.041) were also significantly difference between DSB and SDB. [Conclusion] These results demonstrated that DSB would be the more favorable option than SDB for golfers or coaches trying to improve their drive distance and shot preciseness.

Purpose: This study evaluated the usefulness of International Classification of Functioning, disability and health core set for children and youths with cerebral palsy (ICF-core set for CP) by comparing the Gross Motor Function Measure-88 (GMFM-88), which is the most widely used outcome measure in children with cerebral palsy (ICF-core set for CP). Method: One subject (Female, 14) was evaluated by GMFM-88 and ICF-core set for CP. In addition, the concept of GMFM-88 was compared with the concept of the ICF-core set for CP in compliance with ICF linking rules. The numerical values both of the GMFM-88 categories and the ICF-core set for CP's items were compared. Results: The ICF b760 was linked to the GMFM-88 59~61. d415 was linked to 57~58 of GMFM-88. d450 was linked to GMFM-88's 65~72. d455 was linked to GMFM-88 at 77and 80~83. Conclusion: The association of the ICF-core set for CP and GMFM-88 was confirmed. In addition, the number of categories of ICF-core set for CP was smaller than the number of items of GMFM-88. In conclusion, the ICF-core set for CP is an evaluation tool that can identify the various features of children. In addition, GMFM-88 was linked to the ICF core set for CP according to the ICF linking rules.

This study presents a deep-learning-based framework integrating a single heat-flux sensor for rapid and accurate estimation of core body temperature (CBT). A gated recurrent unit (GRU) model was trained using a large-scale dataset comprising finite-element simulations and experimental transient responses to learn conduction- and convection-governed features. By analyzing only the initial 30 s of temperature signals, the model achieved a mean absolute error below 0.1 °C across a wide range of ambient temperatures (5–35 °C), convective heat transfer coefficients (0–50 W·m⁻²·K⁻¹), and skin conductivities (0.32–0.50 W·m⁻¹·K⁻¹). This data-driven approach eliminated the need for prolonged thermal stabilization, enabling site-independent CBT prediction with reliable performance under dynamic environmental and physiological conditions.

Purpose: Waste parts of zirconia blocks and powders were remained after CAD/CAM process. In order to make these residual zirconia fit for practical use, zirconia single cores were produced by drain casting process. Methods: Remained zirconia blocks were reduced to powders with zirconia mortar, and screened with 180 mesh sieve. Zirconia slip was prepared from waste parts of zirconia by ball milling. Plaster molds for forming cores by slip casting were also prepared. Formed cores were removed from mold after partial drying. Dried cores were biscuit fired at 1,100 for 1hour. Biscuit fired cores were treated with tools to control the fitness and thickness. Finished cores were 2nd fired at 1,500 for 1hour. Microstructure of cross section of core was observed by SEM. Results: When mill pot was filled with 100g of zirconia and alumina mixed powder, 300g of zirconia ball, and 180g of distilled water, the optimum slip for drain casting was obtained. Gypsum plaster for ceramic forming was more suitable then yellow stone plaster for casting process. SEM photograph showed the microstructure of fully dense with uniform grain size of zirconia and well dispersed alumina grains into the zirconia matrix. Conclusion: Zirconia single cores were produced by drain casting process. Drain casting is useful process to make these residual zirconia fit for practical use. Further study will be focused on the preparation of the bridge type cores by casting.

[목적] 이 단일사례 연구의 목적은 코어 근신경 훈련이 유소년 골퍼의 신체 및 골프수행력에 미치는 것을 조사하는 것이다. [방법] 연구대상자는 한국골프중고연맹에 소속된 13세의 남자 골프 선수이다. 13세의 유소년 선수는 주 2-3 회 총 6주 동안 코어 근신경 훈련을 실시하였다. 대상자는 운동중재 전과 후에 허리 근력(폄, 신전), 엉덩 근력(폄, 신 전), 무릎근력(폄, 신전), 윗몸일으키기, 수직점프, 메디슨 볼 던지기, Y-balance test, 클럽 헤드 스피드, 볼 스피드 및 비거리 (드라이버, 7번 아이언)을 측정하였다. 코어 근신경 훈련은 저항, 균형 및 플라이오메트릭 운동을 반영하여 구 성하였다. [결과] 코어 근신경 훈련은 13세 유소년 골퍼의 운동 및 골프 수행력을 긍정적으로 개선하였다. [결론] 이 러한 연구결과는 연령대에 적합하도록 잘 구성된 코어 근신경 훈련이 유소년 골프선수의 골프 능력을 향상시킬 수 있는 훈련 프로그램으로 사용 가능하다는 점을 시사해 주고 있다.

[Purpose] This study aimed to investigate the effects of circuit neuromuscular training (CNT) on physical and golf performance in youth golfers. [Method] The participants of this study were 13-year-old male golf players registered with the Korea Federation of Middle and High Schools. A 13-year-old youth athlete performed CNT 2-3 times a week for 6 weeks. Baseline and post-intervention measures included trunk strength (extension, flexion), hip strength (extension, flexion), knee strength (extension, flexion), sit up, verical jump, medicine ball throw, Y-balance test, club head speed, ball speed, and carry (driver, 7 iron) measurements. CNT consisted of a combination of resistance, balance, and plyometric exercises. [Result] The results of this study showed that CNT positively improved the physical and golf performance of 13-year-old youth golfers. [Conclusion] These results suggest that a well-organized CNT program can be used as a training program to improve the physical and golf performance of youth golfers.

Background: The International Classification of Functioning, Disability, and Health-core set (ICF-core set) for children and youth (CY) with cerebral palsy (CP) provides a useful conceptual framework and a guide for health care planning and measuring the changes brought by interventions across a multitude of dimensions from body functions to personal activities, social participation, and environmental factors for them. Objects: This single case study was reported to illustrate the use of a goal directed approach in applying the ICF-core set for CY with CP from a physical therapist perspective. Methods: An eleven year old boy with spastic CP, Gross Motor Function Classification System (GMFCS) level V, and his mother participated in an evaluation of his functioning state. The intervention goal was set through an interview using the ICF-core set, Canadian Occupational Performance Measure (COPM) and Goal Attainment Scale (GAS). Physical therapy was carried out on an outpatient basis using a goal directed approach for 30 min, 1 time/week during 12 weeks and the boy's gross motor function was assessed using the Gross Motor Function Measure (GMFM)-66 version (item set 2) before and after the intervention. Results: As measured by the boy's mother, the COPM score showed a meaningful clinical change (performance=mean 3.5, satisfaction=mean 2.5) and the T-score of GAS changed 34.4 after the goal directed approach. The GMFM-66 (item set 2) score changed from 31.8 to 38.7 and evaluation using the ICF-core set displayed improvement in 6 items of activity level between before and after the intervention. Conclusion: The ICF-core set for CY with CP is useful for understanding the overall functioning of CY with this condition and provides an opportunity to share and integrate information and opinions from different disciplines. We consider it as a useful tool in the universal language for the therapy and education of CY with CP.

국내의 전기수요량은 매년 증가하고 있다. 발전소에서 전력을 생산하고 공급하기위하여 채택된 모든 장비들은 신뢰할 수 있는 상태에서 완전하게 동작하여야 한다. 생산된 고전압의 전기를 공급하기 위한 장비로서 6 kV CV 단심케이블이 사용되고 있다. 케이블 제작사는 케이블의 동작 수명이 약 30년 이라고 공개적으로 알리고 있다. 그러나 설치된 케이블이 동작을 시작함과 동시에, 성능이 악화되는 열화과정이 시작된다. 동작 중인 케이블의 열화 상태로 인한 신뢰성을 진단을 받지 않았기 때문에, 케이블은 예측하지 못하는 시점에서 언제든지 파괴될 수 있다. 우리는 케이블의 사고를 체계적으로 감시 및 예방하기 위한 측정 장비를 개발, 한국서부발전 주식회사(Korea Western Power Co. Ltd.)에 설치하여 활선 케이블을 진단하였다. 이 논문에서 우리는 케이블을 구성하고 있는 도체와 표면온도를 측정하였고, 타사의 데이터와 비교하여 서로가 일치한다는 연구결과를 제시한다.

The demand for electric power is increasing every year in Korea. All the systems adopted at power stations in order to generate and transmit electric power should operate in perfect condition or reliability. The device for transmitting the generated high-voltage electric power is 6 kV CV single core cables. The manufacturing companies of the cables makes an official announcement that the operating lifetime of their cables is about 30years. But from the moment of operation the deterioration precesses of worsening the characteristics of cables starts. Since the reliability for the status of installed cables in deterioration has not been diagnosed, the cables can be broken at any unexpected moments. In order to prevent the abrupt cable accident by systematically monitoring the cable status, we have invented the first device in Korea. We have installed our device at Korea Western Power Co. Ltd. in order to diagnose the live cables. In this paper, we present our research results of measured temperatures of inner conductor and surface and the compared results of those data with other cable company. We also show that our results agree with those made by other company.

There have been recent efforts to establish methods for high-fidelity and multi-physics simulation with coupled thermal-hydraulic (T/H) and neutronics codes for the entire core of a light water reactor under accident conditions. Considering the computing power necessary for a pin-by-pin analysis of the entire core, subchannel-scale T/H analysis is considered appropriate to achieve acceptable accuracy in an optimal computational time. In the present study, the applicability of in-house code CUPID of the Korea Atomic Energy Research Institute was extended to the subchannel-scale T/H analysis. CUPID is a component-scale T/H analysis code, which uses three-dimensional two-fluid models with various closure models and incorporates a highly parallelized numerical solver. In this study, key models required for a subchannel-scale T/H analysis were implemented in CUPID. Afterward, the code was validated against four subchannel experiments under unheated and heated single-phase incompressible flow conditions. Thereafter, a subchannel-scale T/H analysis of the entire core for an Advanced Power Reactor 1400 reactor core was carried out. For the high-fidelity simulation, detailed geometrical features and individual rod power distributions were considered in this demonstration. In this study, CUPID shows its capability of reproducing key phenomena in a subchannel and dealing with the subchannel-scale whole core T/H analysis.

We have demonstrated a highly efficient cladding-pumped ytterbium-doped fiber laser, generating $>$2.1 kW of continuous-wave output power at 1.1 μm with 74% slope efficiency with respect to launched pump power. The beam quality factor ($M^2$) was better than 1.2. The maximum output power was only limited by available pump power, showing no evidence of roll-over even at the highest output power. We present data on how the beam quality depends on the fiber parameter, based on our current and past fiber laser developments. We also discuss the ultimate power-capability of our fiber in terms of thermal management, Raman nonlinear scattering, and material damage, and estimate it to 10 kW.

Hepatitis C virus (HCV) core proteins from two different isolates (HCV-1 and HCV-RH) were expressed in Spotioptera Jrugiperda (Sf9) insect cells. The RH core consisted of two major species of proteins (21 kDa and 19 kDa). On the other hand, the HCV-1 core was approximately 16 kDa in a SDS-PAGE gel. Both core proteins were phosphorylated in vivo on serine residues. Furthermore, the RH core but not HCV-1 core formed dimers, indicating that the protein conformation of the core in these two isolates is dfferent from one another. Immunofluorescence studies showed that the RH core was present in the cytoplasm, whereas the HCV-1 core was localized predominantly to the nucleus in recombinant baculovirus-infected insect cells. Since the major difference between the two isolates is the codon 9 of the core protein, a single amino acid substitution appears to play a major role in the protein conformation and these properties may reflect the different biological functions of core proteins in HCV-infected cells.

We created a new design for an Nd-doped clad-pumped silica fiber laser to enhance the pump absorption and lasing efficiency for a butt-coupled, end-pumped scheme. Two concatenated adiabatic tapers formed within the laser cavity simultaneously removed higher order modes and were spliced to conventional single mode fibers. We theoretically analyzed mode propagation along the composite cavity and experimentally achieved continuous wave oscillation in the $LP_{01}$ mode at $1.06\;{\mu}m$ and a laser output power of over 820 mW with a slope efficiency of 27%.

In eukaryotes, small RNAs play important roles in both gene regulation and resistance to viral infection. Argonaute proteins have been identified as a key component of the effector complexes of various RNA-silencing pathways, but the mechanistic roles of Argonaute proteins in these pathways are not clearly understood. To address this question, we performed single-molecule fluorescence experiments using an RNA-induced silencing complex (core-RISC) composed of a small RNA and human Argonaute 2. We found that target binding of core-RISC starts at the seed region of the guide RNA. After target binding, four distinct reactions followed: target cleavage, transient binding, stable binding, and Argonaute unloading. Target cleavage required extensive sequence complementarity and accelerated core-RISC dissociation for recycling. In contrast, the stable binding of core-RISC to target RNAs required seed-match only, suggesting a potential explanation for the seed-match rule of microRNA (miRNA) target selection.

이 논문에서는 비휘발성 메모리 기반 In-Memory Computing(IMC)를 활용한 단일 코어/다중 레이어 CNN 가속기의 설계 초기 단계에서 가속기의 성능과 면적을 예측하여 최적 메모리 데이터 플로우 및 인터페이스를 탐색할 수 있는 새로운 설계 공간 탐색기를 제안한다. 이를 위해 다양한 메모리 레이아웃, 인터페이스, 매핑 방법을 탐색 공간에 포함하였다. 설계 옵션들을 완전 탐색 방식으로 탐색하고, 성능과 면적을 예측하여 최적 메모리 데이터 플로우 및 인터페이스를 탐색했다. ResNet-18를 목표 네트워크로 설정하고, 제안하는 설계 공간 탐색기를 통해 찾아낸 최적 메모리 데이터 플로우 및 인터페이스는 baseline 대비 면적 효율 측면에서 약 132 배 향상이 가능함을 확인했다.

This paper presents a novel Design Space Explorer(DSE) that can predict the performance and area of a single-core/multi-layer CNN accelerator using non-volatile memory-based In-Memory Computing(IMC) at an early stage of design to explore the optimal memory data flow and interface. To achieve this, we include various memory layouts, interfaces, and mapping methods in the exploration space. Design options were explored in an exhaustive search manner, and the optimal memory data flow and interfaces were explored by predicting performance and area. Using ResNet-18 as the target network, we found that the optimal memory data flow and interface found by the proposed DSE can improve the area efficiency by about 132 times compared to the baseline.

본 논문에서는 빠른 시간 내에 설계자의 요구사양을 만족하는 메모리를 자동으로 합성해주는 새로운 멀티포트 메모리 컴파일러를 제안하였다. 제안한 컴파일러의 장점은 하나의 메모리 코어 셀을 규칙적으로 배치, 확장하여 메모리를 합성하고, 동시에 합성된 메모리내의 임계경로만을 추출하여 빠르게 검증할 수 있다는 것이다. 또한, 레이아웃 상에서의 전원선 공유 등의 기법으로 메모리의 성능을 향상시킬 수 있도록 하였다. 본 컴파일러를 사용하여 0.25$\mu\textrm{m}$ CMOS 1-poly, 2-metal 공정에서 최대 8개의 쓰기 포트, 16개의 읽기 포트, 64워드, 256비트 사이의 여러 가지 멀티포트 메모리를 자동 합성하였다. 합성 결과 메모리의 성능 및 면적 면에서 만족할 만한 결과를 얻었으며, 레이아웃 전체에서의 시뮬레이션 시간보다 10배정도 빠른 시간 내에 동작을 정확히 검증하였다.

본 논문에서는 다중 코어 ARM 프로세서의 NEON SIMD(Single Instruction Multiple Data) 병렬 명령어 및 다중 코어 병렬화를 통하여 심층 신경망의 피드포워드 네트워크 연산을 최적화하는 방안을 제시하였다. SIMD 병렬 명령어를 이용한 최적화의 경우에는 단계 별 최적화 과정에서의 속도 향상과 정밀도를 제시 하였다. 단일 코어 상에서 SIMD 병렬 명령어를 이용하여 구현된 결과는 C 컴파일러를 이용한 구현보다 2.6배의 속도 향상을 얻을 수 있었다. 또한 단일 코어 상에서 최적화된 코드를 다중 코어로 병렬화함으로써 5.7배~7.7배의 속도 향상을 얻을 수 있었다. 이상의 결과를 통하여 이동형 단말기에서도 연산량이 많은 심층 신경망 기술을 활용할 수 있는 가능성을 확인하였다.

In this paper, we propose optimization methods for speeding the feedforward network of deep neural networks using NEON SIMD (Single Instruction Multiple Data) parallel instructions and multi-core parallelization on the multi-core ARM processor. As the result of the optimization using SIMD parallel instructions, we present the amount of speed improvement and arithmetic precision stage by stage. Through the optimization using SIMD parallel instructions on the single core, we obtain $2.6{\times}$ speedup over the baseline implementation using C compiler. Furthermore, by parallelizing the single core implementation on the multi-core, we obtain $5.7{\times}{\sim}7.7{\times}$ speedup. The results we obtain show the possibility for applying the arithmetic-intensive deep neural network technology to applications on mobile devices.

신재생 에너지 분야에 적용되는 계통 연계형 인버터에서는 출력 전류 리플을 감소 및 계통 연계 기준을 만족하기 위하여 필터 인덕터가 필수적으로 사용된다. 현재 출력 인덕터로 적용될 수 있는 코아 중에서 아몰퍼스(Amorphous) 코아 AMCC 250을 사용하였으며, 단상하프브릿지 전압형 인버터의 스위칭은 SPWM 방법을 사용하였다. 본 논문에서는 출력 필터 인덕터 설계시에 사용할 수 있는 코아 손실 분석 방법을 제시하고, 제시된 방법에 따라 코아 손실 값을 도출하였다. 이러한 분석 결과를 실제 제작한 간이 열량계 통하여 검증을 시도하였다.