• 제목/요약/키워드: Forming a good relationship

검색결과 33건 처리시간 0.023초

Optimization of spring back in U-die bending process of sheet metal using ANN and ICA

  • Azqandi, Mojtaba Sheikhi;Nooredin, Navid;Ghoddosian, Ali
    • Structural Engineering and Mechanics
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    • 제65권4호
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    • pp.447-452
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    • 2018
  • The controlling and prediction of spring back is one of the most important factors in sheet metal forming processes which require high dimensional precision. The relationship between effective parameters and spring back phenomenon is highly nonlinear and complicated. Moreover, the objective function is implicit with regard to the design variables. In this paper, first the influence of some effective factors on spring back in U-die bending process was studied through some experiments and then regarding the robustness of artificial neural network (ANN) approach in predicting objectives in mentioned kind of problems, ANN was used to estimate a prediction model of spring back. Eventually, the spring back angle was optimized using the Imperialist Competitive Algorithm (ICA). The results showed that the employment of ANN provides us with less complicated and time-consuming analytical calculations as well as good results with reasonable accuracy.

태교 실천에 대한 일상생활 기술적 연구 (An Ethnographic Study about Taegyo Practice in Korea)

  • 김현옥
    • 대한간호학회지
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    • 제27권2호
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    • pp.411-422
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    • 1997
  • The purpose of this study is twofold : (i) to investigate how much effort the married couples are making for the good health of both the pregnant woman and her unborn child from the time of their marriage to and during the period of conception : and (ii) to comprehensive investigate socio-cultural back-grounds which affect prenatal effort. Result of this study provide a basis for the prenatal care program which will be appropriate to our culture. This study has been done by the ethnographic research method. The subjects of this study are 53 people in all consisting of 33 pregnant women and 20 husbands. In order to investigate socio-cultural factors which influence Taegyo, producers of Taegyo music were interviewed. In addition the researcher surveyed the markets of Taegyo music, participated in special courses of prenatal education, analyzed the content of the books and periodicals dealing with Taegyo, and collected the concept of Taegyo distributed by the mass media. The full-fledged study continued for eight months from February to August.1996. The data were analyzed as soon as they were collected. Spradly's(1979, 1980) developmental, sequential method of domain analysis. taxonomic analysis, componential analysis, and theme analysis in this order was adopted as the procedure of analyzing the data. To obtain the exactness of study, Sandelowski's (1986) four criteria, that is, Credibility, Fittingness, Auditability, and Confirmability were applied to all stages of data collection, data analysis, the interpretation of the result, and the description of the result. The following are the result : 1. The couples' Taegyo at the stage of preconception was related to their physical, psychological, spiritual conditions under which a healthy baby will be born. Specific methods they prefer are : "the choice of one's spouse." "physical check-up," "physical good health, " "praying, " and so on. 2. When the marriod couple have sex in order to conceive, their Taegyo was related to the imposition of their physical, psychological, and environmental conditions. Specific methods they prefer are : "having sex at specific time, " "having sex in nice place." "to purify their minds while having sex," and so on. 3. The married couples' Taegyo while they are in pregnancy was related to the imposition of their physical. psychological, emotionmental. environmental, social and spiritual conditions. Specific methods they prefer are : "listening to music. " "reading," "looking at beautiful things only," "to avoid looking at or listening to bad things." "to eat food in good shape, " "to avoid drugs," "eating Korean herbal medicine." "sexual abstinence," "to avoid dangerous places," "to keep emotional tranquility," "moderate exercises and rest." "leading a pure life." "praying." "being aware of their words and behavior." "for the couple to keep a good relationship." "interaction with their unborn child," "to support Taegyo for pregnant women," and so on. 4. The married couple put Taegyo into practice on the basis of the following principles : the principle of respecting an unborn child, the principle of forming a good disposition. the principle of top-down parental love, the principle of synergy between a pregnant woman and her unborn child, the principle of expecting a good child, the principle of forming a good habit, and the principle of acquiring a parental role. 5. The practice of Taegyo is influenced by such factors as the married couple, the supporting system, and the mass media. As the husband -and-wife factor, their information of Taegyo, the degree of importance is assigned to their characters, their time to spare, their healthiness, the age of pregnant woman, their conception plan, their religion, their belief of the Taegyo effects, and the birth of a baby in this order. The factor of the supporting system consists of her husband's support, her family support, and her neighbor's support. The mass media factors include the broadcasting media, books specialized in Taegyo, periodicals for pregnant women, booklets for advertizing powdered milk, Taegyo music of record manufacturing companies, and the teaching materials for gifted children. Among these the mass media is especially taking advantage of Taegyo as its main source of economic profits are leading the public behavior pattern to a prodigal one. Taegyo is a self-control behavior which requires practice for the following : the physical and psychological good health of the pregnant woman and her unborn child, the development of the unborn child's good character, the development of the unborn child's intelligence and talents, the expectation of the unborn child's good features. shape a good habit, the expectation of the unborn child's bright future, and the learning of a parental role, the expectation of male birth. Above all it is a type of our good cultural tradition which pursues a value higher than the one that the prenatal care does. The principles of pregnancy care inherent in the habit of Taegyo will provide us a guideline for the development of the prenatal care.

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골격성 III급 무치악 환자에서 전치부 중립대를 고려한 총의치 제작 증례 (Complete denture fabrication of a skeletal class III edentulous patient considering anterior neutral zone: a case report)

  • 김수헌;김형준;박상원;임현필;박찬;장우형
    • 구강회복응용과학지
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    • 제40권2호
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    • pp.91-99
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    • 2024
  • 골격성 3급 무치악 환자의 경우 총의치 제작 시 잔존치조제 관계를 고려하여 교차교합을 형성해 줌으로써 의치의 안정을 얻을 수 있다. 골격성 3급 악간관계에서 전치부를 정상교합 관계로 형성하는 것은 전방 캔틸레버를 가중시켜 의치의 안정을 저하시킬 수 있다. 하지만, 환자들은 총의치를 사용할 때 기능적인 면 뿐 아니라 심미적인 면 또한 중요시한다. 전치부 인공치들이 어떻게 배열되느냐에 따라 총의치의 심미성이 좌우되어, 골격성 3급 악간관계를 갖는 무치악 환자에서 정상교합이나 절단교합을 활용한 총의치 제작 증례가 보고되고 있다. 본 증례에서는 3급 악간관계를 갖는 무치악 환자에게 상악 전치부에 중립대를 고려하여 전치부 절단교합을 형성하여 의치를 제작하였고, 우수한 심미적, 기능적 결과를 얻었다.

반용융 성형에서 A356합금의 최적 재가열 과정에 대한 연구 (A Study on the Optimum Reheating Profess of A356 Alloy in Semi-Solid Forming)

  • 윤재민;박준홍;김영호;최재찬
    • 한국정밀공학회지
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    • 제19권2호
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    • pp.114-125
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    • 2002
  • As semi-solid forging (SSF) is compared with conventional easting such as gravity die-easting and squeeze casting, the product without inner defects can be obtained from semi-solid forming and globular microstructure as well. Generally speaking. SSF consists of reheating, forging, ejecting precesses. In the reheating process, the materials are heated up to the temperature between the solidus and liquidus line at which the materials exists in the form of liquid-solid mixture. The process variables such as reheating time, reheating temperature, reheating holding time, and induction heating power have much effect on the quality of the reheated billets. It is difficult to consider all the variables at the same time when predicting the quality. In this paper, Taguchi method, regression analysis and neural network were applied to analyze the relationship between processing conditions and solid fraction. A356 alloy was used for the present study, and the learning data were extracted by the reheating experiments. Results by neural network were on good agreement with those by experiment. Polynominal regression analysis was formulated by using the test data from neural network. Optimum processing condition was calculated to minimize the grain size, solid fraction standard deviation, otherwise, to maximize the specimen temperature average. In this time, discussion is liven about reheating process of row material and results are presented with regard to accurate process variables for proper solid fraction, specimen temperature and grain size.

임의 형상의 다이를 이용한 반용융 단조 공정의 유한요소해석 (A Finite Element Analysis of Thixoforging Process by using Arbitrarily Shaped Dies)

  • 강충길;김남석
    • 한국정밀공학회지
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    • 제16권9호
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    • pp.123-134
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    • 1999
  • A new forming technology has been developed to fabricate near-net shape components by using aluminum alloys with globular microstructure. The estimations of filling characteristic in the forging simulation with arbitrarily shaped dies of SSM are calculated by finite element method with proposed algorithm. The proposed model and various boundary conditions for arbitrarily shaped die are investigated with the coupling calculation between the liquid phase flow and the solid phase deformation. The simulation processes with arbitrarily shaped dies are performed on the isothermal conditions and axisymmetric problems. To analyze the forging process simulation with SSM, new stress-strain relationship for semi-solid behaviour is described, and forging the liquid flow. Furthermore, For the purpose of getting net shape of SSM, it is important to be obtain a solid fraction in forging process with arbitrarily shaped dies. To produce a automotive part which have good mechanical properties, the filling pattern in accordance with die velocity and solid fraction distribution has to be estimated for arbitrarily shaped die.

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Humic acid 제거를 위한 국산 입상활성탄의 흡착성능 평가에 관한 연구 (A Study on Evaluation of Adsorption Performance of Humic Acid on Granular Activated Carbon)

  • 신성교;김종구;박청길
    • 한국환경과학회지
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    • 제2권1호
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    • pp.73-81
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    • 1993
  • Adsorption process using granular activated carbon(GAC) has been considered as one of the most effective water treatment technologies to remove humic acid which is recon- niEed as trihalomethane(THM) precursor in chlorination. To design the most effective GAC process, it is necessary to conduct the test of adsor- ption performance by means of isothem, batch rate and column studies and to select the most effective activated carbon according to raw materials of GAC - lignite and coconut shell. The objective of this study is to investigate the adsorption performance of humid acid on two activated carbons - lignite activated carbon(LAC) and coconut shell activated car- bon(CAC) made in Korea. It is available to represent UV-abs and trihalomethane formation potential(THMFP) as concentration of humic acid due to good relationship. The adsorption capacity of humid acid is not concerned with surface area of activated carbon but with pore size related to about $100{\AA}$, and then LAC forming at the extent of mesopore is found to be eight times more effective in adsorption capacity than CAC forming at micropore. The adsorption capacity of LAC and CAC is better at pH 5.5 than at pH 7. Pore and surface diffusion coefficients calculated from the diffusion model are $7.61\times10^{-13}m^2/sec$, $3.52\times10^{-15}m^2/sec$ for CAC, and $3.38\times10^{-12}m^2$/sec and $Ds=1.48{\times}10^{-15}m^2/sec$ for GAC respectively. From the results of column test it shows that the performance of LAC is also better than CAC and the optimal EBCT(Empty Bed Contact Time) is 4.52min. and activated carbon removes selectively the components of humic acid to be easily formed to THM.

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화성 정시영고택의 입지 및 공간배치의 풍수고찰 (A Pungsu Study on Location and Space Lay out of Traditional House of Jeong, Si-Yoeng in Hwaseong)

  • 한종구
    • 한국농촌건축학회논문집
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    • 제24권4호
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    • pp.125-132
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    • 2022
  • It can be seen that Traditional house of Jeong Si-yeong is located in a place where Saenggi(good energy), which is important in Pungsu(Feng Shui), can be gathered and that energy can be properly maintained. According to the theory of feng shui, a place that is not easily exposed by the surrounding mountains and is well protected by the strong wind was selected, and the main room was placed on the south side so that the sunlight was adequate while facing the north, so that you can live a comfortable life for a long time. Located on such a relatively well-hidden site, it is a location that can cope well with the invasion of Japanese invaders through the sea in the past, and even today, it is seen as a reasonable base that can be properly protected from strong sea winds in reality. On the other hand, if we look at the Hyungguk theory, it was a house built in the late Joseon Dynasty, and we could see the hidden hopes of the nobles at the time. The mountain behind the house is a haebok-type with a crab lying on the seashore, and what the crab symbolizes is the past national exam for official. Considering that the name of the place where the house is located is also Oyat(cucumber tree)-ri, where many cucumber trees closely related to the royal family of the Joseon Dynasty were planted, it seems that the family wished for prosperity by producing many Sadaebu(upper class gentry) in the past and forming a good relationship with the royal family.

벌크 비정질 Zr-Ti-Cu-Ni-Be 합금의 고온 압축 변형 특성 (High Temperature Compressive Deformation Behavior of the Bulk Metallic Glass Zr-Ti-Cu-Ni-Be Alloy)

  • 이광석;하태권;안상호;장영원
    • 소성∙가공
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    • 제10권7호
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    • pp.565-572
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    • 2001
  • It is well known that a multicomponent $Zr_{4l.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ bulk metallic glass alloy shows good bulk glass forming ability due to its high resistance to crystallization in the undercooled liquid state. DSC and XRD have been performed to confirm the amorphous structure of the master alloy. To investigate the mechanical properties and deformation behavior of the bulk metallic $Zr_{4l.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ alloy, a series of compression tests has been carried out at the temperatures ranging from $351^{\circ}C$ to $461^{\circ}C$at the various initial strain rates from $2{\times}10^4s^1$ to $2{\times}10^2s^1$. Three types of nominal stress-strain curves have been identified such as linear stress-strain relationship meaning fracture at maximum stress, plastic deformation including stress overshoot and steady-state flow, plastic deformation without stress overshoot depending on the strain rate and test temperature. Also DSC analysis for the compressed specimens was carried out to investigate the change of structure, thermal stability and crystallization behavior for the various test conditions.

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Rapid Detection of Streptococcus mutans Using an Integrated Microfluidic System with Loop-Mediated Isothermal Amplification

  • Jingfu Wang;Jingyi Wang;Xin Chang;Jin Shang;Yuehui Wang;Qin Ma;Liangliang Shen
    • Journal of Microbiology and Biotechnology
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    • 제33권8호
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    • pp.1101-1110
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    • 2023
  • Streptococcus mutans is the primary causative agent of caries, which is one of the most common human diseases. Thus, rapid and early detection of cariogenic bacteria is critical for its prevention. This study investigated the combination of loop-mediated isothermal amplification (LAMP) and microfluid technology to quantitatively detect S. mutans. A low-cost, rapid microfluidic chip using LAMP technology was developed to amplify and detect bacteria at 2.2-2.2 × 106 colony-forming units (CFU)/ml and its detection limits were compared to those of standard polymerase chain reaction. A visualization system was established to quantitatively determine the experimental results, and a functional relationship between the bacterial concentration and quantitative results was established. The detection limit of S. mutans using this microfluidic chip was 2.2 CFU/ml, which was lower than that of the standard approach. After quantification, the experimental results showed a good linear relationship with the concentration of S. mutans, thereby confirming the effectiveness and accuracy of the custom-made integrated LAMP microfluidic system for the detection of S. mutans. The microfluidic system described herein may represent a promising simple detection method for the specific and rapid testing of individuals at risk of caries.

벌크 비정질 Zr-Ti-Cu-Ni-Be 합금의 고온 소성 변형 특성 (High Temperature Plastic Deformation Behaviors of the Bulk Metallic Glass Zr-Ti-Cu-Ni-Be Alloy)

  • 이광석;하태권;안상호;장영원
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2001년도 추계학술대회 논문집
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    • pp.272-276
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    • 2001
  • Multicomponent $Zr_{41.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ bulk matallic glass alloy shows good bulk glass forming ability due to its high resistance to crystallization in the undercooled liquid state.1) In this study, DSC and X-ray diffractometry have been performed to confirm the amorphous structure of the master $Zr_{41.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ alloy. To investigate the mechanical properties and deformation behaviors of the bulk metallic $Zr_{41.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ alloy, a series of compression tests has been carried out at the temperatures ranging from $351^{\circ}C$ to $461^{\circ}C$ and at the various initial strain rates from $2{\times}10^{-4}s^{-1}\;to\;2{\times}10^{-2}s^{-1}$. There are two types of nominal stress-strain curves. The one shows linear stress-strain relationship meaning fracture at maximum stress, the other shows plastic deformation including steady-state flow. Also DSC analysis for the compressed specimens has been performed to investigate the change of thermal stability and crystallization behavior for the various test conditions.

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