• Title/Summary/Keyword: 측정표준기술

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Survey of Current Status of Casting Industry in Korea (국내 주조산업 현황조사)

  • Cho, Minsu;Lee, Jisuk;Lee, Sanghwan;Lee, Sangmok
    • Journal of Korea Foundry Society
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    • v.41 no.2
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    • pp.144-152
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    • 2021
  • Based on the analysis of the current state of the world's foundry industry, we looked at the international competitiveness of Korea's foundry industry for the past 20 years. Korea's total foundry production is 2.52 million tons, and the production per company (so-called productivity) is 2,831 tons, which is the eighth largest in the world and down one position for the case of total foundry production, while productivity remains its position compared to three years ago. Korea is the only one of the top 10 foundry to see a decline in production. Similar to the global situation, Korean products consist of 38% of grey csat iron, 31% of ductile cast iron, 15% of aluminum, and 9% of cast steel. In order to obtain statistics on Korea's foundry industry, the survey conducted a service project for approximately nine months from April 2020. Various statistical surveys and sample in-depth surveys by the Korean standard industry class were evaluated for various contents of the domestic casting industry. We also looked at the number of companies, the distribution by region, the number of workers and the percentage of foreigners, and the distribution of each job, as well as the R&D investment status according to the size of the enterprise. Together, sales, exports, sales and various profit ratios were analyzed to measure the earning power of foundry industry. In addition, the classification by grouping the foundry industry according to the process utilized by focusing on each company, and to determine the sales, exports, and yield status for each process was also investigated on the basis. Based on these data, the domestic foundry industry has presented a variety of offers for the following issues for sustainable growth; global ranking, marginal corporate restructuring, training of domestic technical people, differentiated support policies by company size and process.

The Study of Fat Infiltration Ratio in Lumbar Paraspinal Muscle of Patient with Herniated Intervertebral Lumbar Disc (요추간판 수핵 탈출증 환자의 요부 척추 주위근 내 지방침윤 비율에 관한 연구)

  • Kong, Bong-Jun;Lee, Jung-Ho;Yong, Min-Sik;Kim, Jin-Sang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.11
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    • pp.5254-5260
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    • 2012
  • The purpose of this study is to find the relationship between lumber Herniated Nuclesus Pulposus of specific part and fat infiltration in paraspinal muscle. Also we intended to find the relationship between Body Mass Index(BMI) and fat infiltration ratio in the lumber paraspinal muscle based on the sexes of patients. We conducted this study of patients who visited our hospital from May, 2010 to May, 2012. The subjects are composed of 40 patients(20 females and 20 males), who are 30 to 50 years old suffering from severe lumber herniated nuclesus pulposus, who had or were going to have operation treatment. BMI is measured through anthropometry of each patient and fat infiltration inside the muscle is estimated by measuring the cross section area of lumbar paraspinal muscle from mid-cross section of disc(L2-S1) and fat infiltration ratio. The data of this study are analyzed by independent t-test to figure out the difference of fat infiltration between male and female, and by paired sample T-test after getting mean and standard deviation to find the changes of fat infiltration of lumbar on each level. Also correlation analysis is done by setting age as a control variable to find the correlation between BMI and fat infiltration of the whole lumbar. As a result, we could get only the meaningful difference between the sexes on upper lumber part(L2-L3) while we couldn't find any significant difference in the rest of lumbar(L3-S1). Besides, the changes of fat infiltration ratio on each lumbar level increased rapidly from lumbar 3,4 to lumbar 4,5. We also found that there is no correlation between fat infiltration ratio of lumbar paraspinal muscle(L2-S1) and BMI.

The Simulation for the Organization of Fishing Vessel Control System in Fishing Ground (어장에 있어서의 어선관제시스템 구축을 위한 모의실험)

  • 배문기;신형일
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.36 no.3
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    • pp.175-185
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    • 2000
  • This paper described on a basic study to organize fishing vessel control system in order to control efficiently fishing vessel in Korean offshore. It was digitalized ARPA image on the fishing processing of a fleet of purse seiner in conducting fishing operation at Cheju offshore in Korea as a digital camera and then simulated by used VTMS. Futhermore, it was investigated on the application of FVTMS which can control efficiently fishing vessels in fishing ground. The results obtained were as follows ; (1) It was taken 16 minutes and 35 minutes to casting and hauling net in fishing processing respectively. The length of rope pulled by scout boat was 200m, tactical diameter in casting net was 340.8m, turning speed was 6kts as well. (2) The processing of casting and hauling net was moved to SW, NE as results of simulation when the current direction and speed set into NE, 2kts and SW, 2kts respectively. Such as these results suggest that can predict to control the fishing vessel previously with information of fishing ground, fishery and ship's maneuvering, etc. (3) The control range of VTMS radar used in simulation was about 16 miles. Although converting from a radar of the control vessel to another one, it was continuously acquired for the vector and the target data. The optimum control position could be determined by measuring and analyzing to distance and direction between the control vessel and the fleet of fishing vessel. (4) The FVTMS(fishing vessel traffic management services) model was suggested that fishing vessels received fishing conditions and safety navigation information can operate safely and efficiently.

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A Study on the Use of Active Protocol Using the Change of Pitch and Rotation Time in PET/CT (PET/CT에서 Pitch와 Rotation Time의 변화를 이용한 능동적인 프로토콜 사용에 대한 연구)

  • Jang, Eui Sun;Kwak, In Suk;Park, Sun Myung;Choi, Choon Ki;Lee, Hyuk;Kim, Soo Young;Choi, Sung Wook
    • The Korean Journal of Nuclear Medicine Technology
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    • v.17 no.2
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    • pp.67-71
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    • 2013
  • Purpose: The Change of CT exposure condition have a effect on image quality and patient exposure dose. In this study, we evaluated effect CT image quality and SUV when CT parameters (Pitch, Rotation time) were changed. Materials and Methods: Discovery Ste (GE, USA) was used as a PET/CT scanner. Using GE QA Phantom and AAPM CT Performance Phantom for evaluate Noise of CT image. Images are acquired by using 24 combinations that four stages pitch (0.562, 0.938, 1.375, 1.75:1) and six stages X-ray tube rotation time (0.5s-1.0s). PET images are acquired using 1994 NEMA PET Phantom ($^{18}F-FDG$ 5.3 kBq/mL, 2.5 min/frame). For noise test, noise are evaluated by standard deviation of each image's CT numbers. And then we used expectation noise according to change of DLP (Dose Length Product) to experimental noise ratio for index of effectiveness. For spatial resolution test, we confirmed that it is possible to identify to 1.0 mm size of the holes at the AAPM CT Performance Phantom. Finally we evaluated each 24 image's SUV. Results: Noise efficiency were 1.00, 1.03, 1.01, 0.96 and 1.00, 1.04, 1.02, 0.97 when pitch changes at the QA Phantom and AAPM Phantom. In case of X-ray tube rotation time changes, 0.99, 1.02, 1.00, 1.00, 0.99, 0.99 and 1.01, 1.01, 0.99, 1.01, 1.01, 1.01 at the QA Phantom and AAPM Phantom. We could identify 1.0 mm size of the holes all 24 images. Also, there were no significant change of SUV and all image's average SUV were 1.1. Conclusion: 1.75:1 pitch is the most effective value at the CT image evaluation according to pitch change and It doesn't affect to the spatial resolution and SUV. However, the change of rotation time doesn't affect anything. So, we recommend to use the effective pitch like 1.75:1 and adequate X-ray tube rotation time according to patient size.

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Improvement of GPS positioning accuracy by static post-processing method (정적 후처리방식에 의한 GPS의 측위정도 개선)

  • 김민선;신현옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.4
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    • pp.251-261
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    • 2003
  • To measure the GPS position accuracy and its distribution according to the length of the baseline, 30 minutes to 24 hours observations at the fixed location were conducted with two GPS receivers (Ll, 12 channels) on May 29 to June 2, 2002. The GPS data received at the reference station, the rover station and the ordinary times GPS observation station operated by the National Geography Institute in Korea were processed in kinematic and static post-processing methods with a post -processing software. The results obtained are summarized as follows: 1. The number of the satellite that could be observed continuously more than six hours was 16 and most of these satellites were positioned at east-west direction on May 31, 2002. The number of the satellite observed and the geometric dilution of precision (GDOP) determined by the average of every 10 minute for the day were 8 and 3.89, respectively. 2. Both the average GPS positions before and after post-processing were shifted (standalone: 1.17 m, post -processing: 0.43m) to the south and west. The twice distance root mean square (2drms) measured with standalone was 6.65m. The 2drms could be reduced to 33.8% (standard deviation 0=17.2) and 5.3% (0=2.2) of standalone by the kinematic and the static post-processing methods, respectively. 3. The relationship between the length of the baseline x (km) and the 2drms y (m) obtained by the static post-processing method was y=0.00l6x+0.006 $(R^2=0.87)$. In the case of the positioning with the static post-processing method using the GPS receiver, it was found that a positioning within 20cm 2drms was possible when the length of the baseline was less than 100km and the receiving time of the GPS is more than 30 minutes.

A Study on Mechanical Errors in Cone Beam Computed Tomography(CBCT) System (콘빔 전산화단층촬영(CBCT) 시스템에서 기계적 오류에 관한 연구)

  • Lee, Yi-Seong;Yoo, Eun-Jeong;Kim, Seung-Keun;Choi, Kyoung-Sik;Lee, Jeong-Woo;Suh, Tae-Suk;Kim, Joeng-Koo
    • Journal of radiological science and technology
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    • v.36 no.2
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    • pp.123-129
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    • 2013
  • This study investigated the rate of setup variance by the rotating unbalance of gantry in image-guided radiation therapy. The equipments used linear accelerator(Elekta Synergy TM, UK) and a three-dimensional volume imaging mode(3D Volume View) in cone beam computed tomography(CBCT) system. 2D images obtained by rotating $360^{\circ}$and $180^{\circ}$ were reconstructed to 3D image. Catpan503 phantom and homogeneous phantom were used to measure the setup errors. Ball-bearing phantom was used to check the rotation axis of the CBCT. The volume image from CBCT using Catphan503 phantom and homogeneous phantom were analyzed and compared to images from conventional CT in the six dimensional view(X, Y, Z, Roll, Pitch, and Yaw). The variance ratio of setup error were difference in X 0.6 mm, Y 0.5 mm Z 0.5 mm when the gantry rotated $360^{\circ}$ in orthogonal coordinate. whereas rotated $180^{\circ}$, the error measured 0.9 mm, 0.2 mm, 0.3 mm in X, Y, Z respectively. In the rotating coordinates, the more increased the rotating unbalance, the more raised average ratio of setup errors. The resolution of CBCT images showed 2 level of difference in the table recommended. CBCT had a good agreement compared to each recommended values which is the mechanical safety, geometry accuracy and image quality. The rotating unbalance of gentry vary hardly in orthogonal coordinate. However, in rotating coordinate of gantry exceeded the ${\pm}1^{\circ}$ of recommended value. Therefore, when we do sophisticated radiation therapy six dimensional correction is needed.

Effect of Nurida-Ball exercise on muscle function, spinal alignment, and dynamic balance capacity in Middle-Aged Men (누리다 볼 운동이 중년 남성의 근기능, 척추정렬 및 동적 균형능력에 미치는 영향)

  • Choi, Dong-Hun;Kim, Tae-Kyung;Park, Jae-Myoung;Jung, Jong-Hwan;Yeom, Dong-Chul;Cho, In-Ho;Cho, Joon-Yong;Koo, Jung-Hoon
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.6
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    • pp.1556-1566
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    • 2020
  • The purpose of this study was to investigate the effect of Nurida-Ball exercise on isokinetic muscle function, spinal alignment, and dynamic balance capacity in middle-aged men. All middle-aged men(n=16) were divided into 2 groups: Ball exercise(BE, n=8) and control(CON, n=8) group. BE group performed the Nurida-Ball exercise(30 min/day, 3 days/week, 8 weeks) and isokinetic knee and trunk muscle function, spinal alignment, and dynamic balance capacity were measured. All of the measured variables calculated the mean and standard deviation and verified normality using the Shapiro-Wilk test. The independent t-test method and the Paired t-test method were then analyzed to identify differences between groups. This study found that isokinetic knee and trunk muscle function was significantly strengthened in the BE compared with CON group by increasing peak torque(PT) of right and left knee extension(60°/sec, p<0.01, respectively), average power(AP) of right and left knee extension(60°/sec, p<0.05, p<0.01, respectively), and PT of right knee flexion(180°/sec, p<0.05) and AP of right knee extension(180°/sec, p<0.05). In the change of isokinetic trunk muscle function, only PT of trunk extension(180°/sec) was increased in the BE compared with the CON group(p<0.05). In addition, Nurida-ball exercise can improve the spinal alignment by reducing the trunk inclination(p<0.05) in the BE compared with the CON group. Finally, dynamic balance capacity was also enhanced in the BE compared with the CON group by decreasing the score of overall balance index(OBI, p<0.01) and Antero-posterior balance index(p<0.05) in the Stage-6, and OBI(p<0.05) in the Stage-1. This result demonstrated that Nurida-ball exercise may improve spinal alignment, dynamic balance capacity, and isokinetic muscle function, which might be an effective way for the improvement of health-related fitness in middle-aged men.

Development and Evaluation of a Community Staged Education Program for the Cardiocerebrovascular Disease High-risk Patients (심뇌혈관질환 고위험군을 위한 지역사회 단계별 교육프로그램 개발 및 효과 평가)

  • Lee, Hye-Jin;Lee, Jung-Jeung;Hwang, Tae-Yoon;Kam, Sin
    • Journal of agricultural medicine and community health
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    • v.37 no.3
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    • pp.167-180
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    • 2012
  • Objective: This study was conducted to evaluate an education program for cardiocerebrovascular high-risk patients. Methods: This program was developed according to Tyler's model for curriculum development. To evaluate the effects of this program, we measured clinical outcome change (weight, waist circumference, systolic blood pressure, diastolic blood pressure) and behavior change stages (checking blood pressure, blood sugar levels, doing physical activity, consistent maintenance of food intake, eating low amounts of salt, abstention from tobacco and alcohol) before and 4 weeks after participation in the education program. The group of subjects consisted of High-risk group patients who attended basic program(32 patients), and staged program(37 patients) during KHyDDI meetings from Oct. 2009 to May 2010. Results: The staged educational program was developed three aspects(disease, nutrition and exercise)and three stages(basic, in-depth and individual education). In the staged education program, the evaluations were made by measuring clinical outcome and stage of behavior before and after education. Significant differences were found in waist circumference, systolic blood pressure, diastolic blood pressure, consistent maintenance of food intake(p<0.05), and eating low salt(p<0.001)and their self efficacy. Conclusion: In the practice-oriented staged education program, significant differences were found in the clinical outcomes and stage of behavior before and after education. Possible limitations of the study include the small number of participating subjects and the short follow-up management period, but the results indicate that continued application of this program could contribute to the prevention of cardiocerebrovascular diseases for the elderly patients with long periods of chronic diseases.

Computer Assisted EPID Analysis of Breast Intrafractional and Interfractional Positioning Error (유방암 방사선치료에 있어 치료도중 및 분할치료 간 위치오차에 대한 전자포탈영상의 컴퓨터를 이용한 자동 분석)

  • Sohn Jason W.;Mansur David B.;Monroe James I.;Drzymala Robert E.;Jin Ho-Sang;Suh Tae-Suk;Dempsey James F.;Klein Eric E.
    • Progress in Medical Physics
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    • v.17 no.1
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    • pp.24-31
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    • 2006
  • Automated analysis software was developed to measure the magnitude of the intrafractional and interfractional errors during breast radiation treatments. Error analysis results are important for determining suitable planning target volumes (PTV) prior to Implementing breast-conserving 3-D conformal radiation treatment (CRT). The electrical portal imaging device (EPID) used for this study was a Portal Vision LC250 liquid-filled ionization detector (fast frame-averaging mode, 1.4 frames per second, 256X256 pixels). Twelve patients were imaged for a minimum of 7 treatment days. During each treatment day, an average of 8 to 9 images per field were acquired (dose rate of 400 MU/minute). We developed automated image analysis software to quantitatively analyze 2,931 images (encompassing 720 measurements). Standard deviations ($\sigma$) of intrafractional (breathing motion) and intefractional (setup uncertainty) errors were calculated. The PTV margin to include the clinical target volume (CTV) with 95% confidence level was calculated as $2\;(1.96\;{\sigma})$. To compensate for intra-fractional error (mainly due to breathing motion) the required PTV margin ranged from 2 mm to 4 mm. However, PTV margins compensating for intefractional error ranged from 7 mm to 31 mm. The total average error observed for 12 patients was 17 mm. The intefractional setup error ranged from 2 to 15 times larger than intrafractional errors associated with breathing motion. Prior to 3-D conformal radiation treatment or IMRT breast treatment, the magnitude of setup errors must be measured and properly incorporated into the PTV. To reduce large PTVs for breast IMRT or 3-D CRT, an image-guided system would be extremely valuable, if not required. EPID systems should incorporate automated analysis software as described in this report to process and take advantage of the large numbers of EPID images available for error analysis which will help Individual clinics arrive at an appropriate PTV for their practice. Such systems can also provide valuable patient monitoring information with minimal effort.

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Wideband CMOS Voltage-Controlled Oscillator(VCO) for Multi-mode Vehicular Terminal (융복합 차량 수신기를 위한 광대역 전압제어 발진기)

  • Choi, Hyun-Seok;Diep, Bui Quag;Kang, So-Young;Jang, Joo-Young;Bang, Jai-Hoon;Oh, Inn-Yul;Park, Chul-Soon
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.6
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    • pp.63-69
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    • 2008
  • Reconfigurable RF one-chip solutions have been researched with the objective of designing for smaller-sized and more economical RF transceiver and it can be applied to a vehicular wireless terminal. The proposed voltage-controlled oscillator satisfies the targeted frequency range ($4.2{\sim}5.4\;GHz$) and the frequency planning which correspond to the standards such as CDMA(IS-95), PCS, GSM850, EGSM, WCDMA, WLAN, Bluetooth, WiBro, S-DMB, DSRC, GPS, and DVB-H/DMB-H/L(L Band). In order to improve phase noise performance, PMOS is adopted in the cross-coupled pair, the tail current source and MOS varactor in this VCO and differential-typed switching is proposed in capacitor array. Based on the measurement results, a total power dissipation is $5.3{\sim}6.0\;mW$ at 1.8 V power supply voltage. The oscillator is tuned from 4.05 to 5.62 GHz; The tuning range is 33%. The phase noise is -117.16 dBc/Hz at 1 MHz offset frequency and the FOM (Figure Of Merit) is $-180.84{\sim}-180.5$.

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