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Nonlinear Effects of Remittances Paid on Macroeconomics in Malaysia

  • TAASIM, Shairil Izwan
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.2
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    • pp.783-790
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    • 2021
  • The remittances play a major and a very critical role in promoting economic growth and development activities in the developing countries. In this study, the relationship between per capita gross domestic product (GDP) and remittances paid has been investigated based on the case studies in Malaysia from 1987 to 2018. Data was collected from various sources namely statistical yearbook by World Bank and Asian Development Bank. All variables are expressed in natural logarithm form. The technique utilized is the nonlinear autoregressive distributed lags (hereafter NARDL) approach which was introduced by Shin et al.(2014) to examine both short run and long run relationships, as well as the direction of causality, due to the asymmetric relationship between GDP and remittances. The bound test verifies asymmetric cointegration among the variables. The empirical results show that the remittances paid has a momentous short-run and long-run effect towards capital accumulation in Malaysia. Remittances also increase a positive relationship with capital accumulation for Malaysia. We found that remittances form a significant source of external capital and investment for developing countries especially Malaysia which helps in promoting economic development. Furthermore, as a developing country, foreign workers are a source of income to the receiving countries and an indicator to boost sender countries.

Neutronics study on small power ADS loaded with recycled inert matrix fuel for transuranic elements transmutation using Serpent code

  • Vu, Thanh Mai;Hartanto, Donny;Ha, Pham Nhu Viet
    • Nuclear Engineering and Technology
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    • v.53 no.7
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    • pp.2095-2103
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    • 2021
  • A small power ADS design using thorium oxide and diluent matrix reprocessed fuel is proposed for a high transmutation rate, small reactivity swing, and strong safety features. Two fuel matrices (CERCER and CERMET) and different recycled fuel compositions recovered from UO2 spent fuels with 45 GWd/tU and 60 GWd/tU burnup were investigated to determine the suitable fuel for the ADS. It was found that the transmutation of each isotope depends on TRU initial loading amount. After examining the cores, the results show that CERCER fueled ADS has a negative coolant void reactivity (CVR) and a smaller radiotoxicity at discharge compared to that of CERMET core. It implies that CERCER fuel has enhanced safety features and more flavor in terms of radiotoxicity management. To increase fuel utilization and core operation efficiency, a simple assembly shuffling pattern for the CERCER fueled ADS is also proposed. Eigenvalue and burnup calculations were conducted using Serpent 2 with ENDF/B-VII.0 library in both kcode and external source modes, and it indicates that the results of transmutation analyses obtained by kcode only is reliable to discuss the transmutation potential of ADS. Burnup calculation with the fixed-source mode is essential to be used for more practical results of the transmutation by ADS.

Simulation, design optimization, and experimental validation of a silver SPND for neutron flux mapping in the Tehran MTR

  • Saghafi, Mahdi;Ayyoubzadeh, Seyed Mohsen;Terman, Mohammad Sadegh
    • Nuclear Engineering and Technology
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    • v.52 no.12
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    • pp.2852-2859
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    • 2020
  • This paper deals with the simulation-based design optimization and experimental validation of the characteristics of an in-core silver Self-Powered Neutron Detector (SPND). Optimized dimensions of the SPND are determined by combining Monte Carlo simulations and analytical methods. As a first step, the Monte Carlo transport code MCNPX is used to follow the trajectory and fate of the neutrons emitted from an external source. This simulation is able to seamlessly integrate various phenomena, including neutron slowing-down and shielding effects. Then, the expected number of beta particles and their energy spectrum following a neutron capture reaction in the silver emitter are fetched from the TENDEL database using the JANIS software interface and integrated with the data from the first step to yield the origin and spectrum of the source electrons. Eventually, the MCNPX transport code is used for the Monte Carlo calculation of the ballistic current of beta particles in the various regions of the SPND. Then, the output current and the maximum insulator thickness to avoid breakdown are determined. The optimum design of the SPND is then manufactured and experimental tests are conducted. The calculated design parameters of this detector have been found in good agreement with the obtained experimental results.

Burning Characteristics of Wood-based Materials using Cone Calorimeter and Inclined Panel Tests

  • Park, Joo-Saeng;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.30 no.3
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    • pp.18-25
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    • 2002
  • Research to discuss the fire performance of materials requires tools for measuring their burning characteristics and validated fire growth models to predict fire behavior of the materials under specific tire scenarios using the measured properties as input for the models. In this study, burning characteristics such as time to ignition, weight loss rate, flame spread, heat release rate, total heat evolved, and effective heat of combustion for four types of wood-based materials were evaluated using the cone calorimeter and inclined panel tests. Time to ignition was affected by not only surface condition and specific gravity of the tested materials but also the type and magnitude of heat source. Results of weight loss rate, measured by inclined panel tests, indicated that heat transfer from the contacted flame used as the heat source into the inner part of the specimen was inversely proportional to specific gravity of material. Flame spread was closely related with ignition time at the near part of burning zone. Under constant and severe external heat flux, there was little difference in weight loss rate and total heat evolved between four types of wood-based panels. More applied heat flux caused by longer ignition time induced a higher first peak value of heat release rate. Burning characteristics data measured in this study can be used effectively as input for fire growth models to predict the fire behavior of materials under specific fire scenarios.

A Case Study of Different Configurations for the Performance Analysis of Solid Oxide Fuel Cells with External Reformers (외부 개질형 평판형 고체 산화물 연료전지 시스템 구성법에 따른 효율특성)

  • Lee, Kang-Hun;Woo, Hyun-Tak;Lee, Sang-Min;Lee, Young-Duk;Kang, Sang-Gyu;Ahn, Kook-Young;Yu, Sang-Seok
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.3
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    • pp.343-350
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    • 2012
  • A planar solid oxide fuel cell (PSOFC) is studied in its application in a high-temperature stationary power plant. Even though PSOFCs with external reformers are designed for application from the distributed power source to the central power plant, such PSOFCs may sacrifice more system efficiency than internally reformed SOFCs. In this study, modeling of the PSOFC with an external reformer was developed to analyze the feasibility of thermal energy utilization for the external reformer. The PSOFC system model includes the stack, reformer, burner, heat exchanger, blower, pump, PID controller, 3-way valve, reactor, mixer, and steam separator. The model was developed under the Matlab/Simulink environment with Thermolib$^{(R)}$ modules. The model was used to study the system performance according to its configuration. Three configurations of the SOFC system were selected for the comparison of the system performance. The system configuration considered the cathode recirculation, thermal sources for the external reformer, heat-up of operating gases, and condensate anode off-gas for the enhancement of the fuel concentration. The simulation results show that the magnitude of the electric efficiency of the PSOFC system for Case 2 is 12.13% higher than that for Case 1 (reference case), and the thermal efficiency of the PSOFC system for Case 3 is 76.12%, which is the highest of all the cases investigated.

Evaluation of External Quality of Brand Soybeans (콩 시판 브랜드 제품의 외관 품질 평가)

  • Jong, Seung-Keun;Woo, Shun-Hee;Kim, Hong-Sig
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.52 no.3
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    • pp.239-248
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    • 2007
  • Although high nutritional values and continuous identification of important functional substances of soybean [Glycine max (L.) Merrill.] promote consumption of soybean products worldwide, informations on quality of brand soybean is not enough for consumers. Total of 100 brand soybeans [32 for soypaste and source, 45 black testa (lage), and 17 black testa (small) or medicinal soybean and beansprout soybean] were collected at supermarkets and several external quality factors were analyzed. Brand soybeans were marked with the environmental friendly and intimating words along with soybean (white or yellow), black soybean (black-, frost-, late frost-, green or inner-green-), medicinal soybean and beansprout soybean. Among 100 brand soybeans 30% was 1 kg package and 59% was 500 g package, difference between printed and actual weights of 70% brand soybeans was ${\pm}1%$ and weights of 2/3 of brand soybeans were higher than printed weight. Range of 100 seed weights of soypaste and source, black testa (large) and black testa (small) and beansprout soybeans were $23.7{\sim}47.8g$, $21.9{\sim}44.5g$ and $9.5{\sim}15.0g$, respectively. Although ranges of 100 seed weights of soypaste and source and black testa (large) soybeans were similar, 63% of soypaste and source were less than 29 g, while 78% of black testa (large) soybeans were higher than 30 g. Although average and highest percentages of seeds separated with 6.7 mm sieve were similar with 87.4% and 99.9% for soypaste and source soybean and 86.5% and 99.5% for black testa (large) soybean, respectively, the lowest percentages were 70.7% for soypaste and source soybean and 14.4% for black testa (large) soybean. When 100 seed weight was greater than 35 g, 90% of seeds were remained on 6.7 mm sieve. On the other hand 100 g weight and percentage of seeds remained on 6.7 mm sieve showed significantly positive correlations [r=0.7488** for soypaste and source soybean and r=0.7874** for black testa (large) soybean when 100 seed weight was $20{\sim}30g$. Based on hilum color and/or appearance, 76% of brand soybeans collected (more than 90% in yellow testa soybeans) were found to be mixed more than 10% with other cultivars or landraces. Foreign materials such as sand, piece of clothe, wood piece, dead insects, other soybeans were found in 20% of brand soybeans. Average test weight of brand soybeans was 762g $L^{-1}$ with a range of $645{\sim}820g\;L^{-1}$. Soybeans from local markets were as good as brand soybeans in 100 seed weight, uniformity of seeds, weight of foreign materials and test weight.

A Study on the Course Keeping Ability under Wave Condition Considering Ship's Maneuverability (조종성능을 고려한 파랑 중 선박의 직진성능에 관한 연구)

  • Kang, Dong-Hoon;Lee, Soon-Sup;Lee, Seung-Jae
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.19 no.2
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    • pp.193-199
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    • 2013
  • Course keeping ability of ships under wave are analyzed with wave. The simulation with three degrees of freedom is developed and 3-D source distribution method is applied to get wave force for the simulation. The simulation is conducted with the restriction of maximum rudder angle and time delay of control and regular wave and irregular wave are considered as the source of external forces. Simulations with ships which have different maneuverability with tuned hydrodynamic coefficients are developed to assess the variation of the course keeping ability depending on the ship's maneuvering characteristics. The course Keeping ability is evaluated by comparison of distance while the ships are simulated with autopilot control.

The DC/DC Converter having the current source applying the new switching pattern (새로운 스위치 패턴을 적용한 전류원을 갖는 DC/DC 컨버터)

  • Kim, Sun-Pil;Ko, Hyun-Swok;Kim, Se-Min;Park, Seong-Mi;Park, Sung-Jun
    • Journal of the Korean Society of Industry Convergence
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    • v.20 no.4
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    • pp.275-284
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    • 2017
  • As the high-level of the industrial and information age, the electricity become the indispensable element in the daily life including OA, FA, and computer, electric home appliances, and etc. In particular, The continuous use of the high capacity power supply system by applying a Switching Mode Power Supply(SMPS) according to the increase of the secondary side output terminal of the power load of the refrigerator of the home appliance or automation of the plant is pressed. The purpose using the way with this kind of high-capacity altogether is to supply the output voltage and output current regardless of the input voltage or to the external environmental conditions of the secondary-side load fluctuation. In this paper, a combination of a Buck Converter with Boost Converter by making a constant current source to control the inductor current and maintain stable power supply side operating characteristics, when load variations. While maintaining the same characteristics as conventional Buck Converter, and offer a DC-DC Converter system with the new switch pattern having a wide output range capable of operating in Buck-Boost Converter. In addition, after theoretical analysis, we carry out simulations and experiments to verify the validity and performance comparing with a conventional DC-to-DC converter.

Quantitative Evaluation of Radiation Dose Rates for Depleted Uranium in PRIDE Facility

  • Cho, Il Je;Sim, Jee Hyung;Kim, Yong Soo
    • Journal of Radiation Protection and Research
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    • v.41 no.4
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    • pp.378-383
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    • 2016
  • Background: Radiation dose rates in PRIDE facility is evaluated quantitatively for assessing radiation safety of workers because of large amounts of depleted uranium being handled in PRIDE facility. Even if direct radiation from depleted uranium is very low and will not expose a worker to significant amounts of external radiation. Materials and Methods: ORIGEN-ARP code was used for calculating the neutron and gamma source term being generated from depleted uranium (DU), and the MCNP5 code was used for calculating the neutron and gamma fluxes and dose rates. Results and Discussion: The neutron and gamma fluxes and dose rates due to DU on spherical surface of 30 cm radius were calculated with the variation of DU mass and density. In this calculation, an imaginary case in which DU density is zero was added to check the self-shielding effect of DU. In this case, the DU sphere was modeled as a point. In case of DU mixed with molten salt of 50-250 g, the neutron and gamma fluxes were calculated respectively. It was found that the molten salt contents in DU had little effect on the neutron and the gamma fluxes. The neutron and the gamma fluxes, under the respective conditions of 1 and 5 kg mass of DU, and 5 and $19.1g{\cdot}cm^{-3}$ density of DU, were calculated with the molten salt (LiCl+KCl) of 50 g fixed, and compared with the source term. As the results, similar tendency was found in neutron and gamma fluxes with the variation of DU mass and density when compared with source spectra, except their magnitudes. Conclusion: In the case of the DU mass over 5 kg, the dose rate was shown to be higher than the environmental dose rate. From these results, it is concluded that if a worker would do an experiment with DU having over 5 kg of mass, the worker should be careful in order not to be exposed to the radiation.

Knitwear Consumers′Demographic Characteristics and Evaluation Criteria

  • Han, Sung-Ji;Kim, Moon-Sook
    • The International Journal of Costume Culture
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    • v.3 no.2
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    • pp.136-146
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    • 2000
  • The purpose of this study was to investigate the effect of demographic characteristics and general buying characteristics of knitwear consumers on evaluation criteria and information source searching. In this study, a self-administered questionnaire was distributed to young career women and female undergraduate students. Of 580 questionnaires, 496 were used in the following analysis. The data was analyzed with the SPSS package. The research method used factor and reliability analysis to segment consumers by their knitwear evaluation criteria. T-test, one-way ANOVA and χ²were used to characterize the impact of characteristics of the consumer on knitwear evaluation criteria and information source searching in buying knitwear. The results of this study were as follows. First, the information sources of consumers were significantly different depending on their demographic characteristics(age). According to the difference in relationship between the age of consumers and information sources, the younger the consumer, the more information in fashion magazine, the older, in fashion advertisement on catalog. Second, the knitwear evaluation criteria of consumers was classified according to six characteristics - quality, price, aesthetic, situation, self-expression and external. Their knitwear evaluation criteria were significantly different depending on demographic characteristics(job, age, education, marital status) and the general buying characteristics of knitwear(annual knitwear/clothing buying expense and frequency). Career women and married women placed significant importance on practical aspects like quality and price characteristics, while undergraduate students and single women placed significant importance on practical aspects like quality and price characteristics, while undergraduate students and single women placed significant importance on aesthetic and self-expression characteristics. Also, a group with higher annual knitwear/clothing buying expense and frequency considered aesthetic and self-expression characteristics more important. The lower the annual knitwear/clothing buying expense and frequency, the higher a group considered quality and price characteristics more important.

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