• Title/Summary/Keyword: Convergence Condition

Search Result 1,717, Processing Time 0.028 seconds

A Comparison Analysis on the Efficiency of Solar Cells of Shingled Structure with Various ECA Materials (다양한 ECA 소재를 활용한 shingled 구조의 태양전지 효율 비교 분석)

  • Jang, Jae Joon;Park, Jeong Eun;Kim, Dong Sik;Choi, Won Seok;Lim, Donggun
    • Journal of the Korean Solar Energy Society
    • /
    • v.39 no.4
    • /
    • pp.1-9
    • /
    • 2019
  • Modules using 6 inch cells have problems with loss due to empty space between cells. To solve this problem made by shingled structure which can generate more power by utilizing empty space by increasing the voltage level than modules made in 6inch cell. Thus, in this paper, the c-Si cutting cells were produced using nanosecond green laser, and then the ECA was sprayed and cured to perform cutting cell bonding. Three types of ECA materials (B1, B2, B3) with Ag as the main component were used, and experimental conditions varied from 5 to 120 seconds of curing time, 130 to $210^{\circ}C$ of curing temperature, and 1 to 3 of curing numbers. As a results of experiments varying curing time, B1 showed efficiency 19.88% in condition of 60 seconds, B2 showed efficiency 20.15% in 90 seconds, and B3 showed efficiency 20.27% in 60 seconds. In addition, experiments with varying curing temperature, It was confirmed highest efficiency that 20.04% in condition of $170^{\circ}C$ with B1, 20.15% in condition of $150^{\circ}C$ with B2, 20.27% in condition of $150^{\circ}C$ with B3. These are because the Ag particles are densely formed on the surface to make the conduction path. After optimizing the conditions of temperature and curing time, the secondary-tertiary curing experiments were carried out. as the structural analysis, conditions of secondary-tertiary curing showed cracks that due to damp heat aging. As a result, it was found that the ECA B3 had the highest efficiency of 20.27% in condition of 60 seconds of curing time, $150^{\circ}C$ of curing temperature, and single number of curing, and that it was suitable for the manufacture of Solar cell of shingled structure rather than ECA B1 and B2 materials.

The Analysis of Frame Structure in Farm Vehicle (농장차의 프레임 구조 해석)

  • Pratama, Pandu Sandi;Supeno, Destiani;Woo, Ji-Hee;Lee, Eun-Sook;Park, Cun-Sook;Yoon, Woo-Jin;Chung, Sung-Won;Choi, Won-Sik
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.20 no.1
    • /
    • pp.27-33
    • /
    • 2017
  • An agriculture machines are subjected to different loads conditions. Due to this loads variations there will be certain deformations and stress which affect the performance of the electric vehicle in adverse manner. The purpose of this paper is to analyze the total deformation and stress of the electric farm vehicle middle frame based on the finite element method. The proposed electric farm vehicle has lifting and dumping capability. Therefore, in this research four operational condition such as normal condition, dumping condition, lifting condition, and lifting-dumping condition was analyzed. In this research, the design for whole frame structure is elaborated. According to the mechanical characteristics of the frame, materials are selected and manufacturability requirements are limited. Based on ANSYS 15 software, the finite element model of electric farm vehicle is established to carry out static analysis on full-loaded conditions. The simulation results shows that the proposed design meet the strength requirements and displacement requirements. The maximum deformation 0.53611 mm and maximum stress 30.163 MPa occurred at lifting-dumping condition.

Polling Method based on Weight Table for Efficient Monitoring (효율적인 모니터링을 위한 가중치 테이블 기반의 폴링기법)

  • Mun, Hyung-Jin
    • Journal of Convergence Society for SMB
    • /
    • v.5 no.4
    • /
    • pp.5-10
    • /
    • 2015
  • With the advance of ICT, understanding the condition of network and analysing network monitoring have become an important issue. On the TCP/IP network, SNMP is the typical protocol that catches the condition of network by using polling method. If polling method is implemented for a long period, to catch the change of the condition of the network is not easy. On the other hand, in case of short-term polling, even if it could catch the condition of the network in real time, responsive messages to results of the polling cause the increase of traffic and therefore burden the network. There have been studies to control the overhead of responsive messages by controlling the polling period. However, not considering the characteristics of an agent, and running randomly, they cannot decrease the overhead although they would have an instant effect. This paper suggests an efficient polling method that decreases the traffic overhead of polling and catches the condition of the network in real time. Proposed method an polling for a short period and gave weight based on the characteristics of agents to catch the network condition, and a manager decided polling differentially based on the weight so that it decreased the overhead of polling traffic.

  • PDF

Study on the Hydraulic Characteristics Caused by Tree-Planting Conditions in a Natural Channel (하도내 식생상태가 수리학적 특성에 미치는 영향에 관한 연구)

  • Lee, Jeung-Seok;Ahn, Seung-Seop;Choi, Yun-Young
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.3 no.4
    • /
    • pp.319-327
    • /
    • 2000
  • In this study, the hydraulic characteristics variation of flood level caused by tree-planting condition in channel section is evaluated through the examination and analysis of back water characteristics in a natural channel within urban area where the improvement is completed. The study channel is Sinchun runs through the center of Taegu metropolitan city. For the analysis, the comparative examination of runoff characteristics depend on tree- planting condition performed for the flood level of the most upstream point, and velocity of study channel when the project flood flows according to three cases that existing channel is improved to the pro-natural channel, the roughness condition of both riverside highlands is changed, and the composition rate of trees in the riverside highlands is changed. It is known that the variation ranges of the flood level increase remarkably in general, and of the velocity decrease from the result of the examination for the hydraulic characteristics parameters at the most upstream point depend on the tree-planting condition of the channel section when the project flood flows. From the results of the above study on the variation of the hydraulic characteristics according to the tree-planting condition in channel section, it is known that the hydraulic characteristics when the project flood flows in channel have close relationship with the section properties and the slope of channel.

  • PDF

Analysis of Drawbead Process by Static-Explicit Finite Element Method

  • Jung, Dong-Won
    • Journal of Mechanical Science and Technology
    • /
    • v.16 no.12
    • /
    • pp.1687-1692
    • /
    • 2002
  • The problem analyzed here is a sheet metal forming process which requires a drawbead. The drawbead provides the sheet metal enough tension to be deformed plastically along the punch face and consequently, ensures a proper shape of final products by fixing the sheet to the die. Therefore, the optimum design of drawbead is indispensable in obtaining the desired formability. A static-explicit finite element analysis is carried out to provide a perspective tool for designing the drawbead. The finite element formulation is constructed from static equilibrium equation and takes into account the boundary condition that involves a proper contact condition. The deformation behavior of sheet material is formulated by the elastic-plastic constitutive equation. The finite element formulation has been solved based on an existing method that is called the static-explicit method. The main features of the static-explicit method are first that there is no convergence problem. Second, the problem of contact and friction is easily solved by application of very small time interval. During the analysis of drawbead processes, the strain distribution and the drawing force on drawbead can be analyzed. And the effects of bead shape and number of beads on sheet forming processes were investigated. The results of the static explicit analysis of drawbead processes show no convergence problem and comparatively accurate results even though severe high geometric and contact-friction nonlinearity. Moreover, the computational results of a static-explicit finite element analysis can supply very valuable information for designing the drawbead process in which the defects of final sheet product can be removed.

Cancellation of MRI Motion Artifact in Image Plane

  • Kim Eung-Kyeu
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.1 no.1
    • /
    • pp.49-57
    • /
    • 2000
  • In this study, a new algorithm for canceling a MRI artifact due to the translational motion In the image plane is described. Unlike the conventional iterative phase retrieval algorithm, in which there is no guarantee for the convergence, a direct method for estimating the motion is presented. In previous approaches, the motions in the x(read out) direction and the y(phase encoding) direction were estimated simultaneously. However, the feature of x and y directional motions are different from each other. By analyzing their features, each x and y directional motion is canceled by the different algorithms in two steps. First, it is noticed that the x directional motion corresponds to a shift of the x directional spectrum of the MRI signal, and the non-zero area of the spectrum just corresponds to the projected area of the density function on the x axis. So the motion is estimated by tracing the edges between non-zero area and zero area of the spectrum, and the x directional motion is canceled by shifting the spectrum in an reverse direction. Next, the y directional motion is canceled by using a new constraint condition, with which the motion component and the true image component can be separated. This algorithm is shown to be effective by using a phantom image with simulated motion.

  • PDF

Change reaction of fatigue recovery material before and after taping during isokinetic exercise

  • CHOI, Seung-Chul;LEE, Sang-Ho;KIM, Jun-Su
    • The Korean Journal of Food & Health Convergence
    • /
    • v.7 no.3
    • /
    • pp.25-32
    • /
    • 2021
  • This study examined the effects of kinesio taping on recovery from fatigue induced by an exercise of concentric contraction using an isokinetic machine. The fatigue was introduced by a mode of exercise at 60°/sec, 50 repetitions for three sessions. The changes of blood ammonia, lactate, LDH, and CK as a marker of fatigue were monitored. Eight healthy collegiate students participated in two experiments; 1) kinesio taping application condition and 2) no kinesio taping application condition. Before experiments, their physical characteristics were measured. For the experiment, blood samples were taken before and immediately after exercise, and 24hr as well as 72hr of recovery period. Window SPSS package 12.0 version was used and one-way ANOVA with repeated measures were employed. The results were as follows. 1) Blood ammonia tended to reduce along the recovery, but no differences between conditions were noticed. 2) Blood lactate tended to reduce during the recovery period, but differences between conditions were not noticed. 3) The LDH was not different between conditions and CK tended to reduce during the recovery period, but differences between conditions were not noticed. Based on the results, kinesio taping did not influence on recovery phase of blood ammonia, lactate concentration, LDH, and CK.

A Study on Mechanical Characteristics Analysamsarais of PA/GF Composite Materials for Cowl Cross Beam (카울크로스빔용 PA/GF복합재료의 기계적 특성 분석에 관한 연구)

  • Hwan-kuk Kim;Jong-vin Park;Ji-hoon Lee;Heon-kyu Jeong
    • Textile Coloration and Finishing
    • /
    • v.35 no.1
    • /
    • pp.29-41
    • /
    • 2023
  • This study is about a hybrid lightweight cowl crossbeam structure with high rigidity and ability to absorb collision energy to support the cockpit module, which is an automobile interior part, and to absorb energy during a collision. It is a manufacturing process in which composite material bracket parts are inserted and injected into existing steel bars. When considering the mounting condition of a vehicle, the optimization of the fastening condition of the two parts and the mechanical properties of the composite material is acting as an important factor. Therefore, this study is about a composite material having a volume content of Polyamide(PA) and Glass Fiber used as a composite material for a composite material-metal hybrid cowl crossbeam. As a result of analyzing the physical properties of the PA/GF composite material, experimental data were obtained that can further enhance tensile strength and flexural strength by using PA66 rather than PA6 used as a base material for the composite material. And based on this, it contributed to securing the advantage of lightening by using high-stiffness composite material by improving the high disadvantage of the weight of the cowl crossbeam material, which was made only of existing metal materials.

Keratinase Production by Recalcitrant Feather Degrading Pseudomonas Geniculata and Its Plant Growth Promoting Activity (난분해성 우모분해 Pseudomonas geniculata에 의한 케라틴 분해효소 생산 및 식물성장 촉진 활성)

  • Go, Tae-Hun;Lee, Sang-Mee;Lee, Na-Ri;Jeong, Seong-Yun;Hong, Chang-Oh;Son, Hong-Joo
    • Journal of Environmental Science International
    • /
    • v.22 no.11
    • /
    • pp.1457-1464
    • /
    • 2013
  • We investigated the optimal conditions for keratinase production by feather-degrading Pseudomonas geniculata H10 using one variable at a time (OVT) method. The optimal medium composition and cultural condition for keratinase production were determined to be glucose 0.15% (w/v), beef extract 0.08% (w/v), $KH_2PO_4$ 0.12% (w/v), $K_2HPO_4$ 0.02% (w/v), NaCl 0.07% (w/v), $MgSO_4{\cdot}7H_2O$ 0.03%, $MgCl_2{\cdot}6H_2O$ 0.04% along with initial pH 10 at 200 rpm and $25^{\circ}C$, respectively. The production yield of keratinase was 31.6 U/ml in an optimal condition, showing 4.6-fold higher than that in basal medium. The strain H10 also showed plant growth promoting activities. This strain had ammonification activity and produced indoleacetic acid (IAA), siderophore and a variety of hydrolytic enzymes such as protease, lipase and chitinase. Therefore, this study showed that P. geniculata H10 could be not only used to upgrade the nutritional value of feather wastes but also useful in situ biodegradation of feather wastes. Moreover, it is also a potential candidate for the development of biofertilizing agent applicable to crop plant soil.

A study of convergence management types based on self-perception of scalp and hair among college students majoring in cosmetology (미용전공 대학생들의 두피·모발에 대한 자가인식에 기반한 융합적 관리형태 연구)

  • Kang, Su-Youn;Lee, Kyoung-A
    • Journal of the Korea Convergence Society
    • /
    • v.8 no.2
    • /
    • pp.235-241
    • /
    • 2017
  • This study aimed to help the college students majoring in beauty to have interests and manage the functional areas of scalp and hair by accurately identifying the condition of scalp and hair and realizing the convergence management habit and subjective symptoms for the condition. The study conducted a survey on 160 beauty major college universities in their 20s living in the Jeonnam area by asking the subjects to directly write the answers. The study found that many subjects had combination type of scalps and hair problems of split ends and thin hair, and recognized that their hair was damaged. They answered that frequent dyeing and perm caused the damage and they were using the shampoo for damaged hair to prevent hair damage. Regarding the observable symptoms on scalp and hair, it was identified that self-perception was higher as the interest in scalp was high, which influenced age and sleeping time.