• Title/Summary/Keyword: external performance

Search Result 2,887, Processing Time 0.028 seconds

Experiments on Flow Characteristics of Asphalt Seal Composite Waterproofing Method for Underground Concrete Structure Exterior Wall Waterproofing (지하 콘크리트 구조물 외벽 방수용 아스팔트 씰재 복합방수 공법의 흘러내림 특성에 관한 실험)

  • Ko, Sang-Ung;Kim, Kyoung-Hoon;Kim, Young-Sam;Shin, Hong-Chul;Kim, Jin-Man
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.6 no.4
    • /
    • pp.297-303
    • /
    • 2018
  • With the changing trend of the building construction to high rising and large scaling, the underground structure has been increased, and its usage also increased and variety. Hence, to protect the underground structure against underground water, various water proofing methods has been developed. Among the many water proofing methods, the combined water proofing method using both asphalt seal and sheet has been widely used to secure the sufficient performance and decrease the construction failure. However, during the summer period of extremely high temperature conditions, the asphalt sealing materials were separated and leaked into the structure. Therefore, the aim of the research is to provide the quality standard of asphalt sealing material based on the various temperature changes depending on seasons. According to the experimental results, the temperature of the sealing materials applied on the slab was increased up to $54^{\circ}C$ which was $3^{\circ}C$ higher than the structure temperature of $51^{\circ}C$. Based on the melting test for asphalt sealing materials applied on the outside wall of the structure, in the case of water-dispersing typed materials showed significant melting down due to its slow evaporation and low viscosity. Furthermore, from the accelerated test conducted indoor conditions, a solvent-type and water-dispersing typed materials showed significant melting down due to their low viscosity and melting point in ambient conditions. Based on these results, viscosity and melting point are found as the important factors on asphalt sealing materials' quality, and it is necessary to designate the quantitative level of the viscosity and melting point for quality control.

Study on Korean SMEs' Brand Luxuriousness Building (마케팅 믹스를 활용한 한국 중소기업의 브랜드 명품성 구축에 대한 연구)

  • Koh, InKo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.13 no.6
    • /
    • pp.1-14
    • /
    • 2018
  • As interest and consumption of luxury goods have become more popular, luxury goods market is growing rapidly. Consumers can acquire psychological satisfaction with material abundance by purchasing and using luxury goods. Also, from the view of corporations, luxury goods have price inelastic characteristics, so they can enjoy price premium and it is good to produce good performance. That is the reason why they should pay much attention to securing luxuriousness. This study examined the establishment of brands luxuriousness in Korean SMEs. First, it examined the world market of luxury goods industry and the present condition of Korean market. Then it identified the constituents of luxuriousness by examining the prior studies and related literatures, and designed a research model based on the theoretical grounds to suggest the methods of brand luxuriousness building of Korean SMEs. Luxuriousness can be defined as the attribute of product that distinguishes luxury goods from other products by consumers' perceptions, and the factor that provides situational benefits that motivate consumers' purchasing behavior. In this study, I identified the sub-dimensions of luxuriousness according to whether there are product related attributes and consumers' benefit in consideration of the problems of existing studies. Product related luxuriousness are classified into superiority(functional benefit) and scarcity(experiential benefit), while non-product related luxuriousness are classified into differentiation(symbolic benefit) and traditionality(exclusive benefit). The following are the ways to build brand luxuriousness. First, company can use product factors. High quality, excellent design, high recognized brand with strong, favorable and unique images can enhance the luxuriousness of brand. Second, company can use price factors. Consumers tend to perceive luxury goods as high-priced items, so lowering the price of product can undermine the luxuriousness of product. Third, company can use distribution factors. It is effective for making consumers to perceive the differentiation and scarcity of luxuriousness through limited distribution channel. In addition, store atmosphere suitable for luxury brands should be created. Fourth, company can use promotion factors. The more consumers are exposed to advertisements, the more positive attitudes toward luxury brands are made, and consumers recognize luxuriousness higher. Price promotion negatively affects consumers' perception of luxuriousness. Fifth, company can use corporate factors. Consumer evaluations of products are influenced not only by the product attributes but also by the corporate association and corporate image surrounding the product. Considering the existing researches, it is possible to enhance the brand luxuriousness through high corporate competence and good corporate reputation. In order to increase the competence of the enterprise, it is useful to approach multidimensionally in relation with the knowledge creation capability. In corporate reputation, the external stakeholders' reputation is important, but the internal members' reputation is also important. Korean SMEs will be able to build brand luxuriousness by establishing marketing strategies as above and/or mix(integrate) them according to the situation.

A Study on the Development of Assessment Index for Catastrophic Incident Warning Sign at Refinery and Pertrochemical Plants (정유 및 석유화학플랜트 중대사고 전조신호 평가지표 개발에 관한 연구)

  • Yun, Yong Jin;Park, Dal Jae
    • Korean Chemical Engineering Research
    • /
    • v.57 no.5
    • /
    • pp.637-651
    • /
    • 2019
  • In the event of a major accident such as an explosion in a refinery or a petrochemical plant, it has caused a serious loss of life and property and has had a great impact on the insurance market. In the case of catastrophic incidents occurring in process industries such as refinery and petrochemical plants, only the proximate causes of loss have been drawn and studied from inspectors or claims adjustors responsible for claims of property insurers, incident cause investigators, and national forensic service workers. However, it has not been done well for conducting root cause analysis (RCA) and identifying the factors that contributed to the failure and establishing preventive measures before leading to chemical plant's catastrophic incidents. In this study, the criteria of warning signs on CCPS catastrophic incident waning sign self-assessment tool which was derived through the RCA method and the contribution factor analysis method using the swiss cheese model principle has been reviewed first. Secondly, in order to determine the major incident warning signs in an actual chemical plant, 614 recommendations which have been issued during last the 17 years by loss control engineers of global reinsurers were analyzed. Finally, in order to facilitate the assessment index for catastrophic incident warning signs, the criteria for the catastrophic incident warning sign index at chemical plants were grouped by type and classified into upper category and lower category. Then, a catastrophic incident warning sign index for a chemical plant was developed using the weighted values of each category derived by applying the analytic hierarchy process (pairwise comparison method) through a questionnaire answered by relevant experts of the chemical plant. It is expected that the final 'assessment index for catastrophic incident warning signs' can be utilized by the refinery and petrochemical plant's internal as well as external auditors to assess vulnerability levels related to incident warning signs, and identify the elements of incident warning signs that need to be tracked and managed to prevent the occurrence of serious incidents in the future.

Monitoring the Change of Physical Properties of Traditional Dancheong Pigments (전통 단청안료 표면의 물리적 특성 변화 모니터링)

  • Kim, Ji Sun;Jeong, Hye Young;Byun, Doo-Jin;Yoo, Min Jae;Kim, Myoung Nam;Lee, Sun Myung
    • Journal of Conservation Science
    • /
    • v.36 no.6
    • /
    • pp.549-561
    • /
    • 2020
  • This study aimed to assess the performance and life of nine natural mineral dancheong pigments: Seokganju, Jinsa, Hwangto, Jahwang, Wunghwang, Seokrok, Noerok, Seokcheong, and Baekto. The design of the accelerated weathering test considered the domestic climate characteristics and the location of Dancheong. Outdoor weathering tests were conducted at the Research Institute in Daejeon and the Sungnyemun Gate in Seoul to confirm the field reproducibility of the accelerated weathering test. Monitoring of the physical changes in pigments through accelerated and outdoor weathering tests are based on ultraviolet exposure dose. Despite small cracks at the beginning of the tests, the monitoring showed that Seokganju and Baekto had no marked physical changes, but the surface cracks of Jinsa and Seorok continue to expand. Hwangto and Noerok were marked with water or were resin stained, and the particles of Jahwang, Wunghwang, and Seokcheong had lost their luster. Despite the absolute difference in color change in each test, the final chromaticity change patterns of pigments were similar in that the color difference between Baekto and Noerok was below five, and Jina was above 28. The physical and surface color pigment changes were more concentrated in outdoor weathering tests than in accelerated tests, and the Seoul site was more intense than the Daejeon site. This is because outdoor weathering tests are exposed to severe variations of temperature and moisture or deposition of dust particles and, in the case of Seoul, the site is more exposed to the external environment than the Daejeon site.

Development of Digital Transceiver Unit for 5G Optical Repeater (5G 광중계기 구동을 위한 디지털 송수신 유닛 설계)

  • Min, Kyoung-Ok;Lee, Seung-Ho
    • Journal of IKEEE
    • /
    • v.25 no.1
    • /
    • pp.156-167
    • /
    • 2021
  • In this paper, we propose a digital transceiver unit design for in-building of 5G optical repeaters that extends the coverage of 5G mobile communication network services and connects to a stable wireless network in a building. The digital transceiver unit for driving the proposed 5G optical repeater is composed of 4 blocks: a signal processing unit, an RF transceiver unit, an optical input/output unit, and a clock generation unit. The signal processing unit plays an important role, such as a combination of a basic operation of the CPRI interface, a 4-channel antenna signal, and response to external control commands. It also transmits and receives high-quality IQ data through the JESD204B interface. CFR and DPD blocks operate to protect the power amplifier. The RF transmitter/receiver converts the RF signal received from the antenna to AD, is transmitted to the signal processing unit through the JESD204B interface, and DA converts the digital signal transmitted from the signal processing unit to the JESD204B interface and transmits the RF signal to the antenna. The optical input/output unit converts an electric signal into an optical signal and transmits it, and converts the optical signal into an electric signal and receives it. The clock generator suppresses jitter of the synchronous clock supplied from the CPRI interface of the optical input/output unit, and supplies a stable synchronous clock to the signal processing unit and the RF transceiver. Before CPRI connection, a local clock is supplied to operate in a CPRI connection ready state. XCZU9CG-2FFVC900I of Xilinx's MPSoC series was used to evaluate the accuracy of the digital transceiver unit for driving the 5G optical repeater proposed in this paper, and Vivado 2018.3 was used as the design tool. The 5G optical repeater digital transceiver unit proposed in this paper converts the 5G RF signal input to the ADC into digital and transmits it to the JIG through CPRI and outputs the downlink data signal received from the JIG through the CPRI to the DAC. And evaluated the performance. The experimental results showed that flatness, Return Loss, Channel Power, ACLR, EVM, Frequency Error, etc. exceeded the target set value.

Stand-alone Real-time Healthcare Monitoring Driven by Integration of Both Triboelectric and Electro-magnetic Effects (실시간 헬스케어 모니터링의 독립 구동을 위한 접촉대전 발전과 전자기 발전 원리의 융합)

  • Cho, Sumin;Joung, Yoonsu;Kim, Hyeonsu;Park, Minseok;Lee, Donghan;Kam, Dongik;Jang, Sunmin;Ra, Yoonsang;Cha, Kyoung Je;Kim, Hyung Woo;Seo, Kyoung Duck;Choi, Dongwhi
    • Korean Chemical Engineering Research
    • /
    • v.60 no.1
    • /
    • pp.86-92
    • /
    • 2022
  • Recently, the bio-healthcare market is enlarging worldwide due to various reasons such as the COVID-19 pandemic. Among them, biometric measurement and analysis technology are expected to bring about future technological innovation and socio-economic ripple effect. Existing systems require a large-capacity battery to drive signal processing, wireless transmission part, and an operating system in the process. However, due to the limitation of the battery capacity, it causes a spatio-temporal limitation on the use of the device. This limitation can act as a cause for the disconnection of data required for the user's health care monitoring, so it is one of the major obstacles of the health care device. In this study, we report the concept of a standalone healthcare monitoring module, which is based on both triboelectric effects and electromagnetic effects, by converting biomechanical energy into suitable electric energy. The proposed system can be operated independently without an external power source. In particular, the wireless foot pressure measurement monitoring system, which is rationally designed triboelectric sensor (TES), can recognize the user's walking habits through foot pressure measurement. By applying the triboelectric effects to the contact-separation behavior that occurs during walking, an effective foot pressure sensor was made, the performance of the sensor was verified through an electrical output signal according to the pressure, and its dynamic behavior is measured through a signal processing circuit using a capacitor. In addition, the biomechanical energy dissipated during walking is harvested as electrical energy by using the electromagnetic induction effect to be used as a power source for wireless transmission and signal processing. Therefore, the proposed system has a great potential to reduce the inconvenience of charging caused by limited battery capacity and to overcome the problem of data disconnection.

Development of Electret to Improve Output and Stability of Triboelectric Nanogenerator (마찰대전 나노발전기의 출력 및 안정성 향상을 위한 일렉트렛 개발)

  • Kam, Dongik;Jang, Sunmin;Yun, Yeongcheol;Bae, Hongeun;Lee, Youngjin;Ra, Yoonsang;Cho, Sumin;Seo, Kyoung Duck;Cha, Kyoung Je;Choi, Dongwhi
    • Korean Chemical Engineering Research
    • /
    • v.60 no.1
    • /
    • pp.93-99
    • /
    • 2022
  • With the rapid development of ultra-small and wearable device technology, continuous electricity supply without spatiotemporal limitations for driving electronic devices is required. Accordingly, Triboelectric nanogenerator (TENG), which utilizes static electricity generated by the contact and separation of two different materials, is being used as a means of effectively harvesting various types of energy dispersed without complex processes and designs due to its simple principle. However, to apply the TENG to real life, it is necessary to increase the electrical output. In addition, stable generation of electrical output, as well as increase in electrical output, is a task to be solved for the commercialization of TENG. In this study, we proposed a method to not only improve the output of TENG but also to stably represent the improved output. This was solved by using the contact layer, which is one of the components of TENG, as an electret for improved output and stability. The utilized electret was manufactured by sequentially performing corona charging-thermal annealing-corona charging on the Fluorinated ethylene propylene (FEP) film. Electric charges artificially injected due to corona charging enter a deep trap through the thermal annealing, so an electret that minimizes charge escape was fabricated and used in TENG. The output performance of the manufactured electret was verified by measuring the voltage output of the TENG in vertical contact separation mode, and the electret treated to the corona charging showed an output voltage 12 times higher than that of the pristine FEP film. The time and humidity stability of the electret was confirmed by measuring the output voltage of the TENG after exposing the electret to a general external environment and extreme humidity environment. In addition, it was shown that it can be applied to real-life by operating the LED by applying an electret to the clap-TENG with the motif of clap.

Step-by-Step Growth Factors for Technology-Based Ventures: A Case Study of Advanced Nano Products Co. Ltd (기술기반 벤처기업의 단계별 성장요인: (주)나노신소재 사례 중심으로)

  • Jeong, Chanwoo;Lee, Wonil
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.16 no.6
    • /
    • pp.85-105
    • /
    • 2021
  • In this study, a case study was conducted on Advanced Nano Products Co.,Ltd, a company that was established in 2000 and has the core technology to produce and commercialize nano materials and ultrafine nano powders based on nano technology. Deviating from the general case study, a case study analysis frame was set based on the theory of technology management and industry-university cooperation theory, and cases were analyzed. In this case study, Advanced Nano Products Co.,Ltd. was analyzed from two analytical perspectives: the establishment of a Management Of Technology system within the company and the Industry-Academic Cooperation activity. Based on this theoretical-based analysis framework, company visit interviews and related data research and analysis were conducted. As a result of the study of the case company, it was possible to derive how the technology management and industry-university cooperation affect the growth stage of the company as follows. First, the strategic use of technology management is an important factor in strengthening the competitive advantage and core competencies of venture companies, and for survival and growth of startups in the early stages. Second, strategic use of technology management and patents and establishment of a patent management system are a part of business strategy and play a pivotal role in corporate performance. Third, the human and material infrastructure of universities affects the growth of companies in the early stage of start-up, and the high utilization of industry-university cooperation promotes the growth of companies. Fourth, continuous industry-academic cooperation activities in the growth and maturity stages of a company's growth stage are the basis for activating external exchanges and building networks. Lastly, technology management and industry-university cooperation were found to be growth factors for each growth stage of a company. In order for a company to develop continuously from the start-up to the growth and maturity stages, it is necessary to establish a technology management system from the beginning and promote strategic technology management activities. In addition, it can be said that it is important to carry out various industry-academic cooperation activities outside the company. As a result of the case analysis, it was found that Advanced Nano Products Co.,Ltd, which performed these two major activities well, overcame the crisis step by step and continued to grow until now. This study shows how the use of technology management and industry-academic cooperation creates value in each growth stage of technology-based venture companies. In addition, its active use will play a big role in the growth of other venture companies. The results of this case study can be a valid reference for growth research of technology start-up venture companies and related field application and utilization.

Fertigation Techniques Using Fertilizers with Peristaltic Hose Pump for Hydroponics (연동펌프를 이용한 비료염 공급 관비재배기술 연구)

  • Kim, D.E.;Lee, G.I.;Kim, H.H.;Woo, Y.H.;Lee, W.Y.;Kang, I.C.
    • Journal of Practical Agriculture & Fisheries Research
    • /
    • v.17 no.1
    • /
    • pp.57-71
    • /
    • 2015
  • This study was conducted to develop the fertigation system with a peristaltic hose pump and brushless DC motor. The fertigation system was consisted of sensor, main controller, motor control unit, peristaltic pump, water supply pump, control panel, and filter. The peristaltic pump discharges liquid by squeezing the tube with rollers. Rollers attached to the external circumference of the rotor compresses the flexible tube. The fluid is contained within a flexible tube fitted inside a circular pump casing. The developed fertigation system has no mixing tank but instead injects directly a concentrated nutrient solution into a water supply pipe. The revolution speed of the peristaltic pump is controlled by PWM (Pulse width modulation) method. When the revolution speed of the peristaltic pump was 300rpm, the flow rate of the 3.2, 4.8, 6.3mm diameter tube was 202, 530, 857mL/min, respectively. As increasing revolution speed, the flow rate of the peristaltic pump linearly increased. As the inner diameter of a tube larger, a slope of graph is more steep. Flow rate of three roller was more than that of four roller. Flow rate of a norprene tube with good restoring force was more than that of a pharmed tube. As EC sensor probe was installed in direct piping in comparison with bypass piping showed good performance. After starting the system, it took 16~17 seconds to stabilize EC. The maximum value of EC was 1.44~1.7dS/m at a setting value of 1.4dS/m. The developed fertigation system showed ±0.06dS/m deviation from the setting value of EC. In field test, Cucumber plants generally showed good growth. From these findings, this fertigation system can be appropriately suitable for fertigation culture for crops.

Behavior Analysis of Concrete Structure under Blast Loading : (I) Experiment Procedures (폭발하중을 받는 콘크리트 구조물의 실험적 거동분석 : (I) 실험수행절차)

  • Yi, Na Hyun;Kim, Sung Bae;Kim, Jang-Ho Jay;Choi, Jong Kwon
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.29 no.5A
    • /
    • pp.557-564
    • /
    • 2009
  • In recent years, there have been numerous explosion-related accidents due to military and terrorist activities. Such incidents caused not only damages to structures but also human casualties, especially in urban areas. To protect structures and save human lives against explosion accidents, better understanding of the explosion effect on structures is needed. In an explosion, the blast overpressure is applied to concrete structures as an impulsive load of extremely short duration with very high pressure and heat. Generally, concrete is known to have a relatively high blast resistance compared to other construction materials. However, information and test results related to the blast experiment of internal and external have been limited due to military and national security reasons. Therefore, in this paper, to evaluate blast effect on reinforced have concrete structure and its protective performance, blast tests are carried out with $1.0m{\times}1.0m{\times}150mm$ reinforce concrete slab structure at the Agency for Defence Development. The standoff blast distance is 1.5 m and the preliminary tests consists with TNT 9 lbs and TNT 35 lbs and the main tests used ANFO 35 lbs. It is the first ever blast experiment for nonmilitary purposes domestically. In this paper, based on the basic experiment procedure and measurement details for acquiring structural behavior data, the blast experimental measurement system and procedure are established details. The procedure of blast experiments are based on the established measurement system which consists of sensor, signal conditioner, DAQ system, software. It can be used as basic research references for related research areas, which include protective design and effective behavior measurements of structure under blast loading.