• Title/Summary/Keyword: Control of separation

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A Study on the Masking Data in Camera-Back Method with three-aim-point Control (Camera-Back Method 에 있어서 Masking Data에 관한 연구)

  • ChulWhoiKoo
    • Journal of the Korean Graphic Arts Communication Society
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    • v.4 no.1
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    • pp.27-35
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    • 1986
  • Following results about Y,M,C Mask are obtained by the Indirect-Screen Color Separation Method. We make use of experimental system which are in use for the student education. In the Camera-Back Method of reflection copy, the results are summerized as follows.

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Domain-specific Assessment of Psychological Control in Parents of Korean Adolescents : Convergent and Discriminant Validity (청소년기 자녀에 대한 부모의 심리적 통제 구성요소의 타당성 연구 : 분리불안 심리적통제와 성취지향 심리적 통제)

  • Park, Seong-Yeon;Lee, Eun-Gyoung
    • Korean Journal of Child Studies
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    • v.30 no.2
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    • pp.211-229
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    • 2009
  • This study examined replication of the factor structure of the DAPC [Domain-specific Assessment of Psychological Control (Soenens et al., 2006)] in parents of Korean adolescents. Participants included 289 adolescents who responded to DAPC items regarding their parents' psychological control behaviors. Two factors comprising 17 items were identified and labeled as "achievement oriented psychological control", and "separation-anxious psychological control." Confirmatory factor analysis and partial correlation analysis provided evidence for the construct validity of the DAPC through construct reliability, convergent validity and discriminant validity across both sex of parents and adolescents. The psychometric properties indicated that DAPC could be useful in studying parents' psychological control behaviors toward their adolescent children.

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Developmental Toxicity by Exposure to Bisphenol A Diglycidyl Ether during Gestation and Lactation Period in Sprague-dawley Male Rats

  • Hyoung, Un-Jun;Yang, Yun-Jung;Kwon, Su-Kyoung;Yoo, Jae-Hyoung;Myoung, Soon-Chul;Kim, Sae-Chul;Hong, Yeon-Pyo
    • Journal of Preventive Medicine and Public Health
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    • v.40 no.2
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    • pp.155-161
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    • 2007
  • Objectives : Bisphenol A diglycidyl ether (BADGE) is the major component in commercial liquid epoxy resins, which are manufactured by co-reacting bisphenol A with epichlorohydrin. This study was performed to show the developmental effects of prenatal and postnatal exposures to BADGE in male rat offspring. Methods : Mated female rats were divided into four groups, each containing 12 rats. The dosing solutions were prepared by thoroughly mixing BADGE in corn oil at the 0, 375, 1500 and 3000 mg/kg/day concentrations. Mated females were dosed once daily by oral gavage on gestation day (GD) 6 - 20 and postnatal day (PND) 0 - 21. Pregnant female dams were observed general symptoms and body weight. Also, male pups were observed the general symptoms, body weight, developmental parameters (e.g. anogenital distance, pina detachment, incisor eruption, nipple retention, eye opening, testis descent), organ pathologic changes and hormone levels of plasma. Results : Pregnant rats treated with BADGE died at a rate of about 70% in the 1500 mg/kg/day group and all rats treated with 3000 mg/kg/day died. Body weight, for male pups treated with doses of 375 mg/kg/day, was significantly lower than in the control group at PND 42, 56, and 63 (p<0.05). Evaluation of body characteristics including; separation of auricle, eruption of incisor, separation of eyelid, nipple retention, descent of testis, and separation of the prepuce in the BADGE treated group showed no difference in comparisons with the control group. AGD and adjusted AGD (mm/kg) for general developmental items in BADGE 375 mg/kg/day treated pups tended to be longer than in controls, however, these differences were not statistically significant. Relative weights of adrenal gland, lung (p<0.05), brain, epididymis, prostate, and testis (p<0.01) were heavier than in control in measures at PND 9 weeks. There were no significant changes in comparisons of histological findings of these organs. Loss of spermatids was observed in the seminiferous tubule at PND 9 weeks, but no weight changes were observed. The plasma estrogen levels were similar in the control and treatment groups at PND 3, 6 and 9 weeks. The plasma testosterone levels in the control group tended to increase with age. However, in the BADGE 375 mg/kg/day treated male pups it did not tend to increase. Conclusions : These findings suggest that BADGE is a chemical that has developmental effects consistent with it being an endocrine disruptor.

Effect of psychological separation, self-control, college satisfaction on the smartphone addiction of nursing students (간호대학생의 심리적 분리, 자기통제력, 학교만족도가 스마트폰 중독에 미치는 영향)

  • Yang, Hyun Joo
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.4
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    • pp.85-93
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    • 2021
  • The purpose of this study was to investigate the effect of psycological separation, self-control, college satisfaction of smartphone addiction in nursing students. Data were collected from 201 nursing students in B city and analyzed by t-test, ANOVA, Pearson correlation coefficient, and multiple regression using SPSS/WIN 22.0. The degree of smartphone addiction in nursing students was 2.23±.58. There were significant differences in smartphone addiction with respect to alcohol drinking(t=2.530, p=.012), smoking(t=2.302, p=.022), study-time(t=6.036, p=.001), smartphone average daily using time(t=6.036, p=.001). There was negative correlation between smartphone addiction and self-control(r=-.443, p<.001), college satisfaction(r=-.210, p=.033). The factors affecting smartphone addiction of the study subjects were self-control(𝛽=-.355, p<.001), smartphone average daily using time(𝛽=.231, p<.001), smorking(𝛽=-.132, p=.033), with an explanatory power of 27.5%. Through this research requires the fellow study to determine the factors affecting smartphone addiction of nursing students.

Thermal design of reflow oven with PCB-module (이송 모듈을 사용한 리플로우 오븐의 열유동해석)

  • Jeong, Won-Jung;Kwon, Hyun-Goo;Cho, Hyung-Hee
    • Journal of the Semiconductor & Display Technology
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    • v.5 no.3 s.16
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    • pp.29-32
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    • 2006
  • Because of new requirements related to the employment of SMT(Surface Mounting Technology) manufacturing and the diversity of components on high density PCB(Printed Circuit Boards), Thermal control of the reflow process is required in order to achieve acceptable yields and reliability of SMT assemblies. Accurate control of the temperature distribution during the reflow process is one of the major requirements, especially in lead-free assembly. This study has been performed for reflow process using the commercial CFD(Computational Fluid Dynamics) tool for predicting flow and temperature distributions. Porous plate was installed to prevent leakage flow which was one of the major problem of temperature uniformity in the reflow process. There is a separation region where the flow is turned. Outside wall made of porous plate is to prevent and minimize separation region for acquiring uniform temperature during operation. This paper provided design concept from CFD results of the steady state temperature distribution and flow field inside a reflow oven.

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Thermophilic Sewage Sludge Digestion by Anaerobic Sequencing Batch Reactor (고온 협기성 연속회분식 공정에 의한 도시하수슬러지 소화)

  • 허준무;박종안;이종화;손부순;장봉기
    • Journal of environmental and Sanitary engineering
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    • v.14 no.3
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    • pp.130-138
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    • 1999
  • The feasibility of municipal sewage sludge digestion was investigated by using thermophilic anaerobic sequencing batch reactor(ASBR). One-day settle time was enough for the high performance of solid-liquid separation. The conversion of semi-continuous mode to sequencing batch mode is easily achieved without any adverse effects, although the large amount of sludge equal to the volume ratio of 0.3~06 to reactor volume was added in the feed step of the start-up. The ASBRs had higher conversion capability of organics to biogas than the control reactor. Gas yields of the ASBRs were increased by the average of 50% over the control reactor across a range of hydraulic retention time(HRT)s from 10days to 5days. The thermophilic reactors showed higher gas production than mesophilic reactor. Removal efficiencies of organic matter exceeded 80% on the basis of supernatants, except that at the reactor. Solid-liquid separation was essential in the performance of the ASBR, especially, at the lower HFT. The ASBRs were highly efficient in the retention of activated biomass within the reactor. thus compensating for increased equivalent organic loading rate through increased solids retention times followed by the increased solids, while maintaining shorter HRTs.

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Control of Flow Around an Airfoil Using Piezo-Ceramic Actuators (압전세라믹 액추에이터를 이용한 익형 후류 제어)

  • Choi, Jin;Jeon, Woo-Pyung;Choi, Hae-Cheon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.8
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    • pp.1112-1118
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    • 2000
  • The objective of this study is to increase lift and decrease drag of an airfoil at high angles of attack by delaying flow separation with piezo-ceramic actuators. The airfoil used is NACA 0012 and its chord length is 0.3m. An experiment is performed at the freestream velocity of 15m/s at which the Reynolds number based on the chord length is $2{\times}10^5$. Seven rectangular actuators are attached to the airfoil surface and move up and down based on the electric signal. Drag and lift are measured using an in-house two-dimensional force-balance and the surface pressures are also measured. At the attack angle of $16^{\circ}$, the separation point is delayed downstream due to momentum addition induced by the movement of the actuators. Lift is increased by 10%, drag is reduced by 37%, and the efficiency is increased up to 170%. The flow fields with and without control are visualized using the smoke-wire and tuft techniques.

Assessment of Earth Remote Sensing Microsatellite Power Subsystem Capability during Detumbling and Nominal Modes

  • Zahran M.;Okasha M.;Ivanova Galina A.
    • Journal of Power Electronics
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    • v.6 no.1
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    • pp.18-28
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    • 2006
  • The Electric Power Subsystem (EPS) is one of the most critical systems on any satellite because nearly every subsystem requires power. This makes the choice of power systems the most important task facing satellite designers. The main purpose of the Satellite EPS is to provide continuous, regulated and conditioned power to all the satellite subsystems. It has to withstand radiation, thermal cycling and vacuums in hostile space environments, as well as subsystem degradation over time. The EPS power characteristics are determined by both the parameters of the system itself and by the satellite orbit. After satellite separation from the launch vehicle (LV) to its orbit, in almost all situations, the satellite subsystems (attitude determination and control, communication and onboard computer and data handling (OBC&DH)), take their needed power from a storage battery (SB) and solar arrays (SA) besides the consumed power in the EPS management device. At this point (separation point, detumbling mode), the satellite's angular motion is high and the orientation of the solar arrays, with respect to the Sun, will change in a non-uniform way, so the amount of power generated by the solar arrays will be affected. The objective of this research is to select satellite EPS component types, to estimate solar array illumination parameters and to determine the efficiency of solar arrays during both detumbling and normal operation modes.

Numerical analysis of the differential pressure venturi-cone flowmeter (차압식 벤튜리콘 유량계에 대한 유동해석)

  • 윤준용;맹주성;이정원
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.6
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    • pp.714-720
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    • 1998
  • The differential pressure venturi-cone flowmeter is an advanced flowmeter which has many advantages such as wide range of measurement, high accuracy, excellent flow turn-down ratio, low headless, short installation pipe length requirement, and etc. Like other differential pressure flowmeters, the venturi-cone flowmeter uses the law of energy conservation, but its shape and position make it perform better than others. The cone acts as its own flow conditioner and mixer, fully conditioning and mixing the flow prior to measurement. For the analysis, we used Reynolds-averaged Wavier-Stokes equations and k-$\omega$ turbulence model. The equations were fully transformed into the computational domain, the pressure-velocity coupling was made through SIMPLER algorithm, and the equations were discretized using finite analytic solutions of the liberalized equations(Finite Analytic Method). To control the separation phenomenon on the cone surface, we proposed a new shape of cone, and analyzed the flowfield in the new flowmeter system, and found the improvement on the performance of the new cone flowmeter.

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