• Title/Summary/Keyword: Flexible material

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Optimization Methodology for Sales and Operations Planning by Stochastic Programming under Uncertainty : A Case Study in Service Industry (불확실성하에서의 확률적 기법에 의한 판매 및 실행 계획 최적화 방법론 : 서비스 산업)

  • Hwang, Seon Min;Song, Sang Hwa
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.39 no.4
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    • pp.137-146
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    • 2016
  • In recent years, business environment is faced with multi uncertainty that have not been suffered in the past. As supply chain is getting expanded and longer, the flow of information, material and production is also being complicated. It is well known that development service industry using application software has various uncertainty in random events such as supply and demand fluctuation of developer's capcity, project effective date after winning a contract, manpower cost (or revenue), subcontract cost (or purchase), and overrun due to developer's skill-level. This study intends to social contribution through attempts to optimize enterprise's goal by supply chain management platform to balance demand and supply and stochastic programming which is basically applied in order to solve uncertainty considering economical and operational risk at solution supplier. In Particular, this study emphasizes to determine allocation of internal and external manpower of developers using S&OP (Sales & Operations Planning) as monthly resource input has constraint on resource's capability that shared in industry or task. This study is to verify how Stochastic Programming such as Markowitz's MV (Mean Variance) model or 2-Stage Recourse Model is flexible and efficient than Deterministic Programming in software enterprise field by experiment with process and data from service industry which is manufacturing software and performing projects. In addition, this study is also to analysis how profit and labor input plan according to scope of uncertainty is changed based on Pareto Optimal, then lastly it is to enumerate limitation of the study extracted drawback which can be happened in real business environment and to contribute direction in future research considering another applicable methodology.

Design of Fall Impact Protection Pads Using 3D Printing Technology and Comparison of Characteristics according to Structure (3D 프린팅 기술을 활용한 낙상충격 보호패드 설계 및 구조에 따른 특성비교)

  • Park, Jung Hyun;Jung, Hee-Kyeong;Lee, Jeong Ran
    • Journal of the Korean Society of Clothing and Textiles
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    • v.42 no.4
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    • pp.612-625
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    • 2018
  • This study designed 16 kinds of basic structure and 4 kinds of modified structure for impact protection pads with a spacer fabric shape. The pad is a structure in which hexagonal three-dimensional units, composed of a surface layer and a spacer layer, are interconnected. Designed pads were printed with flexible $NinjaFlex^{(R)}$ materials using a FDM 3D printer. The printed pads were evaluated for impact protection performance, compression properties and sensory properties. The evaluation of the impact protection performance indicated that basic structures better than CR foam material at 20cm height were DV1.5, DX1.5, DX1.0, DV1.0 and HV1.5. The evaluation of the compression properties for the five types, with good results in the impact protection performance, indicated that DV1.0, DX1.0, DV1.5, HV1.5 and DX1.5 showed good results, respectively. The sensory evaluation of DV1.0, DX1.0, and DV1.5, which with good results when considering both the impact protection performance and the compression performance, showed that DV1.0 were the best for surface, flexibility, compression and weight. Therefore, DV1.0 is shown to be the best structure for protection pads.

Study of the Carrier Injection Barrier by Tuning Graphene Electrode Work Function for Organic Light Emitting Diodes OLED (일함수 변화를 통한 그래핀 전극의 배리어 튜닝하기)

  • Kim, Ji-Hun;Maeng, Min-Jae;Hong, Jong-Am;Hwang, Ju-Hyeon;Choe, Hong-Gyu;Mun, Je-Hyeon;Lee, Jeong-Ik;Jeong, Dae-Yul;Choe, Seong-Yul;Park, Yong-Seop
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.111.2-111.2
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    • 2015
  • Typical electrodes (metal or indium tin oxide (ITO)), which were used in conventional organic light emitting devices (OLEDs) structure, have transparency and conductivity, but, it is not suitable as the electrode of the flexible OLEDs (f-OLEDs) due to its brittle property. Although Graphene is the most well-known alternative material for conventional electrode because of present electrode properties as well as flexibility, its carrier injection barrier is comparatively high to use as electrode. In this work, we performed plasma treatment on the graphene surface and alkali metal doping in the organic materials to study for its possibility as anode and cathode, respectively. By using Ultraviolet Photoemission Spectroscopy (UPS), we investigated the interfaces of modified graphene. The plasma treatment is generated by various gas types such as O2 and Ar, to increase the work function of the graphene film. Also, for co-deposition of organic film to do alkali metal doping, we used three different organic materials which are BMPYPB (1,3-Bis(3,5-di-pyrid-3-yl-phenyl)benzene), TMPYPB (1,3,5-Tri[(3-pyridyl)-phen-3-yl]benzene), and 3TPYMB (Tris(2,4,6-trimethyl-3-(pyridin-3-yl)phenyl)borane)). They are well known for ETL materials in OLEDs. From these results, we found that graphene work function can be tuned to overcome the weakness of graphene induced carrier injection barrier, when the interface was treated with plasma (alkali metal) through the value of hole (electron) injection barrier is reduced about 1 eV.

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Biofiltration of Gaseous Toluene Using Activated Carbon Containing Polyurethane Foam Media (활성탄 함유 폴리우레탄 담체를 사용하는 바이오필터에 의한 가스상 톨루엔의 처리)

  • Amarsanaa Altangerel;Shin Won-Sik;Choi Jeong-Hak;Choi Sang-June
    • Journal of Environmental Science International
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    • v.15 no.6
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    • pp.513-525
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    • 2006
  • In recent decades, biofiltration has been widely accepted for the treatment of contaminated air stream containing low concentration of odorous compounds or volatile organic compounds (VOCs). In this study, conventional biofilters packed with flexible synthetic polyurethane (PU) foam carriers were operated to remove toluene from a contaminated air stream. PU foams containing various amounts of pulverized activated carbon (PAC) were synthesized for the biofilter media and tested for toluene removal. Four biofilter columns were operated for 60 days to remove gaseous toluene from a contaminated air stream. During the biofiltration experiment, inlet toluene concentration was in the range of 0-150 ppm and EBRT (i.e., empty bed residence time) was kept at 26-42 seconds. Pressure drop of the biofilter bed was less than 3 mm $H_2O/m$ filter bed. The maximum removal capacity of toluene in the biofilters packed with PU-PAC foam was in the order of column II (PAC=7.08%) > column III (PAC=8.97%) > column I (PAC=4.95%) > column IV (PAC=13.52%), while the complete removal capacity was in the order of column II > column I > column III > column IV. The better biofiltration performance in column II was attributed to higher porosity providing favorable conditions for microbial growth. The results of biodegradation kinetic analysis showed that PU-PAC foam with 7.08% of PAC content had higher maximum removal rate ($V_m$=14.99 g toluene/kg dry material/day) than the other PU-PAC foams. In overall, the performance of biofiltration might be affected by the structure and physicochemical properties of PU foam induced by PAC content.

Role of tutor and student in Problem Based Learning (문제중심학습에서 교수와 학생의 역할)

  • Chung Bok-Yae;Yi Ga-Eon;Kim Kyung-Hae
    • The Journal of Korean Academic Society of Nursing Education
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    • v.3 no.2
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    • pp.207-213
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    • 1997
  • Basic science teaching and clinical education should be integrated whenever appropriate, and the development of skills, values, and attitudes which are emphasized to the same extent as the acquisition of knowledge in nursing. Problem-based learning provides a students-centered learning environment and encourages an inquisitive style of learning. The purpose of this paper is to review and comment the role of tutors and students on problem-based learning. The use of problem-based learning places a high demand on faculty members' time and support. The role of tutors in Problem-based learning focuses primarily on issues of developing and teaching the curriculum and on organizational implementation and institutionalization. Tutors are an integral part of course planning. Tutors serve as a constant source of feedback on student needs and concerns to the course director and constitute an informal steering committee while the course is in progress. Tutors write cases, develop student evaluation methods, recommend resources, suggest modifications in lectures and laboratories. Students have a limited amount of time available to study what is traditionally defined as the core content of nursing. But, the role of students in Problem-based learning would be active, independent learners and problem-solvers rather than passive recipients of information. Students using a deep level approach attempt to integrate what they learn with what they already know, to understand the meaning underlying the material to be learned, and to look for explanations rather than facts. Students are encouraged, with appropriate guidance, to define their own learning goals, to select appropriate experiences to achieve these goals, and to be responsible for assessing their own learning progress. Problem-based learning is more flexible and meaningful, by encouraging student interaction, and by having a better emotional climate than the conventional learning.

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A Study on the Analysis of Aesthetic Shape Shown on the Modern Flat Patterned Clothing (현대 평면의에 나타난 형태미에 관한 연구)

  • Kwen, Jin
    • Journal of the Korean Society of Costume
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    • v.56 no.7 s.107
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    • pp.115-125
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    • 2006
  • The study on plane composition in clothing was focused mainly on woven wear earlier but its application has been reaching the knit wear. This study is confined to the utilization with geometrical linear pattern in the modern apparel. The work here intends to grasp the plane structure found in both woven wear and knit wear and, in particular, to understand the aesthetics of fashion. The modern flat patterned clothing has been affected by the oriental style or postmodernism in view of social and cultural aspect while its fabric material and expression method shows the diversity in terms of industrial and technical aspect. It can be characterized as several outstanding patterns: the geometrical pattern in structure, the linear pattern with seam line and 2-dimensional plane pattern without seam line, and the flexible silhouette integrated into one single shape with human body unlike the traditional apparel The aesthetics of fashion in modern flat patterned clothing can be divided into such category as the organically spatial change, the re-creation of tradition and the non-format framework. The organically spatial change shows the geometrical formation in clothes due to change in dimension, where the organically changing uniformity and generosity appears as the dimension progresses. The timeless without any difference of up and down, left and right, and inside and outside and the discontinuity due to limitless spatial change are also imbedded. The re-creation of tradition tells the reshaped spirits of old tradition by integrating and modifying the hereditary features in the old customed clothing into modern clothing. The modern flat patterned clothing implies the contemporaneousness or the frame through which the old and modern cultures may be shared and indicates the re-creation of the past and uniformity. The non-format framework contains the uncertainty in meaning and it doesn't have any certain standards. As both the apparel and the human body with this style aim at the open space, the numerous contingencies are realized.

A Study on Fashion Design Expression Characteristics applied to the concept of the Fold and Ecological Aesthetics (생태미학과 폴드 개념이 적용된 패션디자인 표현특성 연구)

  • Bae, Jungmin
    • Journal of the Korean Society of Costume
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    • v.66 no.5
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    • pp.122-132
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    • 2016
  • In today's society, being considered ecological in fashion design and having a cultural and humanistic approach is important. Using a technological approach, the fold concept was applied to understand and analyze the ecological characteristics of a modern fashion aesthetic design. The concept of 'Ecological Aesthetic Design', which we discuss in this study, is part of human nature, and the design concept is used to consider the relationship between the man and the environment to the design of Victor Papanek. From the perspective of interrelation between the components of an ecosystem, the possibility of the fold's application to ecological aesthetic design can be summarized by wholeness, biodiversity, evolution, homeostasis, and circularity. The concept of the fold is revealed mainly through three types of characteristics: indeterminate complexity, potential continuity, and decentralized interaction relationship. Based on the characteristics of the concept presented earlier, this study conducted a case review by distinguishing contemporary fashion that applied the complex, various, and indeterminate fold concepts into flexible transformation, continuity, and complementary circularity. This study was interpreted from the ecological aesthetic point of view based on the nature of the contingent folds presented before applying modern fashion concepts. It focused on the morphological side, and excluded the material aspects of the case study in order to examine the complex, diverse and content aspects. The result of the study is as follows. The study of the research areas that help the understanding of the changing fashion phenomenonneeds to be encouraged, and there should be a new research category, which can contribute to the ecological aesthetic design concept conversion.

Effect of Solvent Annealing on the Characteristics of PEDOT:PSS as a Ammonia Gas Sensor Film (용매열처리에 따른 PEDOT:PSS 암모니아 가스 감지막 특성 변화)

  • Noh, Wang Gyu;Yeom, Se-Hyuk;Lee, Wanghoon;Shin, Han Jae;Kye, Ji Won;Kwak, Giseop;Kim, Se Hyun;Ryu, Si Ok;Han, Dong Cheul
    • Journal of Sensor Science and Technology
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    • v.26 no.2
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    • pp.96-100
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    • 2017
  • Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been extensively studied as the active material in ammonia gas sensor because of its fast response time, high conductivity and environmental stability. It is well known that a post annealing process for organic devices based on PEDOT:PSS significantly increases the device performance. In this study, we propose the solvent annealing of PEDOT:PSS and investigated its effects. As a results, post solvent annealing on PEDOT:PSS lead to the surface chemical and physical properties change. These changes result in improved conductivity of the PEDOT:PSS. In additional, ammonia sensitivity of solvent annealed PEDOT:PSS become higher than pristine polymer film. The enhancement is mainly caused by the depletion of gas barrier PSS and structural re-forming PEDOT networks. We believe that the post solvent annealing is a promising method to achieve highly sensitivity PEDOT:PSS films for applications in efficient, low-cost and flexible ammonia gas sensor.

Changes in the Water Absorption Properties of Pulp Mold manufactured with Oil Palm EFB by surface treatments (표면처리에 의한 오일팜 EFB 기반 펄프몰드의 흡수특성 변화)

  • Kim, Dong-Sung;Sung, Yong Joo;Kim, Chul-Hwan;Kim, Se-Bin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.1
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    • pp.75-83
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    • 2015
  • The applicability of oil palm biomass, EFB(Empty Fruit Bunch) as raw materials for environmental friendly packaging material, pulp mold, was evaluated in this study. The changes in the water absorption properties of pulp mold by the addition of EFB and the surface treatments with PVA and AKD were analyzed by measuring the changes in the water absorption rate and the water contact angle. The each pulp mold sample was prepared by using laboratory wet pulp molder. And the water absorption rate of each samples were evaluated by measuring times for the absorption of a 0.1 ml water drop on the pulp mold sample surface. The addition of EFB to the pulp mold made of OCC resulted in the decrease of water absorption rate and the increase in the water contact angle. The surface treatments with PVA and AKD on the OCC pulp mold showed the significant reduction in the water absorption rate. However, in case of ONP pulp mold, the addition of EFB and the surface treatments with PVA and AKD showed no big changes in water absorption times. Those might be come from the finer surface structure of ONP pulp mold which were made of more finer and flexible fibers and more hydrophilic fibers. The results of this study showed the functional properties such as water absorption rate, could be controlled by the application of EFB and the treatments with AKD or PVA, especially in case of the OCC pulp mold.

A Study on the Analysis and Improvement methods of Emergency Medical Service Systems in Disaster Areas (재해현장에서의 응급의료체계에 대한 분석과 개선방안)

  • Choi, Keun Myung
    • The Korean Journal of Emergency Medical Services
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    • v.7 no.1
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    • pp.65-80
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    • 2003
  • Various disasters have been continuously occurred in Korea from 1990s to now. However, there is no substantial improvement against damages as compared with the past due to various reasons such as lack of fundamental recognition, ineffective response systems and widespread insensitivity to safety. More worse, new types of disasters have been frequently generated due to rapid changes in social structures and industrial development, unusual changes in weather and changes of international situations. These disasters request comprehensive countermeasures. In particular, while material damages by disasters can be recovered, the losses of precious lives cannot be recuperated in any ways. Thus, it is critical to set effective disaster medical plans. The first way to minimize damages by disasters is the prevention and the next is to set the disaster medical plans focusing on preliminarily activating the emergency medical system to rapidly rescue and take appropriate emergency medical services for casualties in the early stage when any disaster occurs. Nevertheless, no sufficient researches or references do not exist up to now. Even worse, effective emergency medical systems that play critical roles in increasing survival rates of casualties in actual disaster areas is not deployed. For the United States, the consistent countermeasure system is established in FEMA through a close cooperative system with relevant organizations for serious accidents including terrorists' attacks or natural disasters. For the emergency medical services in disasters, the disaster medical plan is set to cope with any disasters in perfect order by special area as operating the National Disaster Medical SystemESF#8 Role by FEMA. Accordingly, we need to set the extensive and integrated disaster prevention system for rapid and flexible operation against various kinds of serious accidents. This study identified overall problems in disaster control plans in Korea and suggested how to improve the emergency medical service system in disaster areas. Furthermore, it aims to prepare the basic data to set the effective emergency medical service plans when substantial casualties break out and more reasonable and systematic disaster control plans to cope with the future occurrence of serious disasters.

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