• 대한기계학회논문집B
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• 제20권2호
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• pp.730-740
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• 1996

Boiling heat transfer coefficients of pure refrigerants (R22, R32, R134a, R125, R290, and R600a) and refrigerant mixtures (R32/Rl34a, R290/ R600a, and R32/R125) are measured experimentally and compared with Chen's correlation. The test section is a seamless stainless steel tube with inner diameter of 7.7mm and uniformly heated by applying electric current directly to the tube. Heat fluxes range from 10 to 30kW$^2$. Mass fluxes are set to 424 ~ 742kg/m$^{2}$s for R22, R32, R134a, R32/R134a, and R32/Rl25 ; 265 ~ 583kg/m$^{2}$s for R290, R600a, and R290/R600a. Heat transfer coefficients depend strongly on heat flux at a low quality region and become independent as quality increases. Convective boiling term in the Chen's correlation predicts experimental data of the pure refrigerants fairly well (relative error of 12.1% for the data of quality over 0.2). The correlation for pure substances overpredicts the heat transfer coefficients for nonazeotropic refrigerant mixtures.

• 설비공학논문집
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• 제5권2호
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• pp.141-155
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• 1993

Thermodynamic properties of R-32 are calculated and its refrigeration performance is evaluated for the purpose the feasibility study of replacing R-22 with R-32. (1) Refrigeration effect of R-32 is superior to that of R-22 because heat of evaporation of R 32 is about 50% higher than that of R-22. However, COP of R-32 system is 10-30% lower than that of R-22 system. It is mainly attributed to the vapor pressore of R-32 being about 62% higher than R-22. (2) Since the pressure ratio and the specific heat ratio of R-32 system is higher than those of R -22, compressor discharging temperature rises as high as to $130-150^{\circ}C$. It may cause mechanical failure of compressor due to the breakdown of lubricant. Compressor should be improved to lower the temperature if R-32 is to replace R-22. (3) Averaged two-phase heat transfer coefficient of R-32 is about 10-20% higher than that of R-22. It may assume better heat exchanger effectiveness but not guarantee the better COP of R-32 system than R-22. (4) The high vapor pressure is the first reason to drop R-32 out of the line of R-22 alternative refrigerant. So, refrigerant mixtures based on R-32 are recommended to adjust the vapor pressure first and keep superior volumetric capacity of R-32.

• 한국정보통신학회논문지
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• 제19권3호
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• pp.507-513
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• 2015

본 논문은 최대 32개의 송수신 안테나를 사용하는 준직교 공간시간 블록부호 (QOSTBC) 를 적용한 대규모 MIMO 시스템을 제안한다. QOSTBC 는 전송율 및 복호 복잡성에 있어서 장점을 가지고 있으며 2개 이상의 송수신 안테나를 적용한 MIMO 시스템에서는 중요한 전송다이버시티 기술이다. 대규모 MIMO 는 매우 많은 송수신 안테나를 적용한 MIMO 시스템이며 최소한 15개 이상의 안테나를 적용하여야 한다. 본 논문은 다양한 안테나 구성 ($2{\times}2$, $4{\times}4$, $8{\times}8$, $16{\times}16$, $32{\times}32$) 으로 QOSTBC를 적용한 대규모 MIMO를 제안하며 BPSK 변조를 적용하여 성능을 분석하였다. 기존 대규모 MIMO 시스템과 비교하여 QOSTBC를 적용한 대규모 MIMO 에서는 송수신 안테나 개수 증가에 따른 다이버시티 이득이 증가하면서 높은 성능 개선 효과를 확인할 수 있었다.

• Korean Chemical Engineering Research
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• 제50권5호
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• pp.913-922
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• 2012

환경 및 화학공업에서 액-액 교반조내의 특성을 파악하는 일은 매우 중요하다. 액적 부근의 물질이동용량계수 $k_La$와 Sauter 평균경 $d_{32}$은 에스테르의 알칼리 가수분해반응을 이용하여 임펠러 부착위치나 액높이를 변화시켜 측정하였다. 그 결과 아래와 같은 이들의 양호한 상관식을 얻었다. $$d_{32}=0.270\(\frac{{\sigma}^{0.6}}{{\rho}^{0.2}P^{0.4}_{Vi}}\)k_La=0.49\(\frac{6{\phi}D_A}{d^2_{32}}\)\(\frac{P_Vd^4_{32}}{{\rho}v^3}\)^{0.193}Sc^{1/3}$$.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.292-298
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• 1991

A new 6-axis robot controller with a high-speed 32-bit floating-point DSP TMS32OC30 has been developed in Samsung Electronics. The controller composed of Intel 80386 microprocessor for the main controller, and TKS32OC30 DSP chip for joint position controller. The characteristics of the controller are high sampling rate of 200us and fast reponsibility. The main controller supports MS-DOS, kinematics, trajectory planning, and sensor fusion functions which are vision, PLC, and MAP. The one high speed DSP chip is used for controlling 6 axes of a robot in 200us simultaneously. The control law applied is PID controller including a velocity feedforvard in joint position controller. The performance tests, such as command following, CP, were conducted for the controller integrated with a 6 axes robot developed in Samsung Electronics. The results showed a good performance. This controller can also perform the system control with other controllers, the communication with high priority controllers, and visual information processing.

• 반도체디스플레이기술학회지
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• 제9권1호
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• pp.61-66
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• 2010

A flat luminaire utilizing 32" flat fluorescent lamp was developed and its optical characteristics were compared with that of the troffer using three T8 regular fluorescent tubes. The optical characteristics of the 32" flat luminaire was similar to that of the troffer.

• Journal of Microbiology and Biotechnology
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• 제24권8호
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• pp.1133-1142
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• 2014

Interleukin-32 (IL-32) is a cytokine and inducer of various proinflammatory cytokines such as $TNF{\alpha}$, IL-$1{\beta}$, and IL-6 as well as chemokines. There are five splicing variants (${\alpha}$, ${\beta}$, ${\gamma}$, ${\delta}$, and ${\varepsilon}$) and IL-$32{\gamma}$ is the most active isoform. We generated human IL-$32{\gamma}$ transgenic (IL-$32{\gamma}$ TG) mice to express high level of IL-$32{\gamma}$ in various tissues, including immune cells. The pathology of sepsis is based on the systemic inflammatory response that is characterized by upregulating inflammatory cytokines in whole body, particularly in response to gram-negative bacteria. We investigated the role of IL-$32{\gamma}$ in a mouse model of experimental sepsis by using lipopolysaccharides (LPS). We found that IL-$32{\gamma}TG$ mice resisted LPS-induced lethal endotoxemia. IL-$32{\gamma}$ reduced systemic cytokines release after LPS administration but not the local immune response. IL-$32{\gamma}TG$ increased neutrophil influx into the initial foci of the primary injected site, and prolonged local cytokines and chemokines production. These results suggest that neutrophil recruitment in IL-$32{\gamma}TG$ occurred as a result of the local induction of chemokines but not the systemic inflammatory cytokine circulation. Together, our results suggest that IL-$32{\gamma}$ enhances an innate immune response against local infection but inhibits the spread of immune responses, leading to systemic immune disorder.

• 전기전자학회논문지
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• 제23권4호
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• pp.1314-1320
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• 2019

본 논문에서는 소프트웨어 환경에서 비트연산을 최적화 하고 DNN으로 응용하는 방법을 제안한다. 이를 위해 비트연산 최적화를 위한 패킹 함수와 DNN으로 응용을 위한 마스킹 행렬 곱 연산을 제안한다. 패킹 함수의 경우는 32bit의 실제 가중치값을 2bit로 변환하는 연산을 수행한다. 연산을 수행할 땐, 임계값 비교 연산을 통해 2bit 값으로 변환한다. 이 연산을 수행하면 4개의 32bit값이 1개의 8bit 메모리에 들어가게 된다. 마스킹 행렬 곱 연산의 경우 패킹된 가중치 값과 일반 입력 값을 곱하기 위한 특수한 연산으로 이루어져 있다. 그리고 각각의 연산은 GPU 가속기를 이용해 병렬로 처리되게 하였다. 그 결과 HandWritten 데이터 셋에 환경에서 32bit DNN 모델에 비해 약 16배의 메모리 절약을 볼 수 있었다. 그럼에도 정확도는 32bit 모델과 비슷한 1% 이내의 차이를 보였다.

• International Journal of Industrial Entomology and Biomaterials
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• 제20권2호
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• pp.107-114
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• 2010

For stable germline transformation, the promoter of Bombyx mori cytoplasmic actin gene (BmA3) has been used for ubiquitous expression of transgenes. So far, no strong promoter is available for ubiquitous expression in B. mori, excluding BmA3 promoter. To identify more powerful promoter than previously reported BmA3 promoter, we isolated 9 clones that show stronger signal compared to BmA3 by a dot blot hybridization. Among these 9 clones, we focused on one clone which has high amino acid homology (85%) with hypothetical protein 32 gene of Lonomia obliqua. This clone, named bHp32 (B. mori hypothetical protein 32) was ubiquitously expressed in all tissues and developmental stage of fifth instar B. mori larvae. As result of promoter assay using dual luciferase assay system, we found the highest transcription activity region (-1,200/+220) in the 5'-flanking region of bHp32 gene, which has 42-fold more intensive promoter activity than BmA3 promoter. Moreover, the bHp32 promoter was normally regulated in Bm5, Sf9, and S2 cells. Therefore, we suggest that bHp32 promoter may be used more powerful and effectively for transgene expression in various insects containing B. mori as a universal promoter.

• 전자공학회논문지B
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• 제31B권10호
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• pp.67-72
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• 1994

In this paper we suggest a 32 bit high speed parallel multiplier which plays an important role in digital signal processing. We employ a bit-pair recoding Booth algoritham that gurantees n/2 partial product terms, which uniformly handles the signed-operand case. While partial product terms are generated, a special method is suggested to reduce time delay by employing 1's complement instead of 2's complement. Later when partial products are added, the additional 1 bit's are packed in a single partial product term and added to in the parallel counter. Then 16 partial product terms are reduced to two summands by using successive parallel counters. Final multiplication value is obtained by a BLC adder. When this multiplier is simulated under 0.8$\mu$CMOS standard cell we obtain 30ns multiplier speed.