• Title/Summary/Keyword: pearl

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Model Predictive Control of Bidirectional AC-DC Converter for Energy Storage System

  • Akter, Md. Parvez;Mekhilef, Saad;Tan, Nadia Mei Lin;Akagi, Hirofumi
    • Journal of Electrical Engineering and Technology
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    • v.10 no.1
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    • pp.165-175
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    • 2015
  • Energy storage system has been widely applied in power distribution sectors as well as in renewable energy sources to ensure uninterruptible power supply. This paper presents a model predictive algorithm to control a bidirectional AC-DC converter, which is used in an energy storage system for power transferring between the three-phase AC voltage supply and energy storage devices. This model predictive control (MPC) algorithm utilizes the discrete behavior of the converter and predicts the future variables of the system by defining cost functions for all possible switching states. Subsequently, the switching state that corresponds to the minimum cost function is selected for the next sampling period for firing the switches of the AC-DC converter. The proposed model predictive control scheme of the AC-DC converter allows bidirectional power flow with instantaneous mode change capability and fast dynamic response. The performance of the MPC controlled bidirectional AC-DC converter is simulated with MATLAB/Simulink(R) and further verified with 3.0kW experimental prototypes. Both the simulation and experimental results show that, the AC-DC converter is operated with unity power factor, acceptable THD (3.3% during rectifier mode and 3.5% during inverter mode) level of AC current and very low DC voltage ripple. Moreover, an efficiency comparison is performed between the proposed MPC and conventional VOC-based PWM controller of the bidirectional AC-DC converter which ensures the effectiveness of MPC controller.

Morphology of Seok in the Great Han Empire Period and the Origin of the Korean Seok's Morphological Characteristics (대한제국시대 석(舃)의 고찰 및 한국 석의 형태적 특징의 유래)

  • Choi, Yeon-Woo
    • Journal of the Korean Society of Costume
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    • v.63 no.8
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    • pp.125-142
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    • 2013
  • Soek(Xi) was the highest ranked shoe that was worn with the primary formal dress in East Asian countries including ancient Korea and China. This article examined Joseon's Seok as discussed in previous studies, and it explored factors such as the wearers' status, wearing situations, its morphology, its materials, and its colors in the Great Han Empire period (1897~1910), and then extracted three morphological characteristics of the Korean Seok to examine its origin. The results of the study are as follows. For women, the Seok in the Great Han Empire period was worn with Won-sam(圓衫) and No-eui(露衣) as well as Jeok-eui(翟衣), and hence its range of wearing was extensive. Also, red Seok was worn with deep red colored Dae-sam(大衫)-styled Jeok-eui in the Joseon period(1392~1897), and blue Seok with deep blue Jeok-eui in the Great Han Empire period. This suggests the possibility that wearing of deep blue Jeok-eui occurred after 1906 in terms of the use of blue Seok. As for its morphology, its leg-less form was maintained into the late Joseon period, and there were no great changes in its name. The characteristics of the Korean Seok's morphological structure consisted of a shoe leg, the wood-less bottom and pearl ornament. As a result of the examination of the origin of those characteristics, it has been clarified that the form in which Gu, Eok, Jun(純), are attached in the structure with a shoe leg originated from the combination of Hwa(靴) and Li(履) after the two types of shoes were alternately worn in the Song (宋) period. Also, it was confirmed that the woodless bottom appeared between the periods from Wei Jin Northern and Southern Dynasties(魏晉南北朝) to Sui(隋), and the pearl ornament occurred in the Jin(金) period.

A Study of the Bezel Settings of a JinjuseonUsed for Joseon Royal Weddings Based on an Examination of the Washers (제조선시대 궁중혼례용 '진주선(眞珠扇)'의 받침못을 통해 본 감장(嵌裝) 기법 고찰)

  • Sim, Myung Bo;Kim, Sun Young
    • Conservation Science in Museum
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    • v.21
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    • pp.17-28
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    • 2019
  • The term jinjuseon(眞珠扇), meaning literally a pearl fan, refers to a fan decorated with precious stones for use in royal wedding ceremonies. This study examined a jinjuseon housed in the National Palace Museum of Korea (NPMK) which currently lacks jeweled ornaments. In order to determine whether pearls or other gemstone settings originally ornamented the fan,the surface and composition of the gray materials remaining on the washers were investigated and the fan was compared with other artifacts decorated using similar techniques. The analysis revealed that the gray materials visible around the round rims of the washers contain tin-lead alloys. The traces of folded nails suggest that soldering was not applied. The remains of the infill observed in other artifacts with bezel settings indicate that this jinjuseon in the NPMK collection was produced using abezel setting technique wherein pearls or other gemstones were affixed by filling cylindrical bezels with tin-lead alloys.

Survival and Growth of the Purplish Washington Clam, Saxidomus purpuratus Spat Sowed in bottom and intermediate culture (개조개, Saxidomus purpuratus의 중간육성 및 씨뿌림된 치패의 성장과 생존)

  • Jin, Young-Guk;Oh, Bong-Se;Jung, Choon-Koo;Kim, Tae-Ik;Park, Min-Woo
    • The Korean Journal of Malacology
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    • v.27 no.3
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    • pp.199-204
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    • 2011
  • We studied possibility of the sowing culture at the bottom after intermediate culture as a method for raising the survival of the Purplish Washington clam, Saxidomus purpuratus. The pearl net ($35cm(W){\times}35cm(B){\times}20cm(H)$) for S. prupuratus spat during the period of intermediate culture (hanging culture) from April to October in 2010. The pearl net (100 inds./net) was installed at two stations (Namhae and Pohang) being about 3-4 m in water depth. After hanging culture, S. prupuratus spat sowed in the bottom of the Gangjin Bay. The survivals (%) of intermediate culture of this species at Namhae station and Pohang station were 73% and 74%, respectively. Daily growth rate of mean shell length and mean weight in Namhae station were higher than those in Pohang station. After sowing at the bottom of the Gangjin Bay, its survival (%) showed 73.98% in January 2011. These results suggested the possibility of the intermediate culture as hanging culture for raising survival rate of S. prupuratus.

A Study on Orientalism in the Paintings of Delft School in 17th Century Netherlands (17세기 네덜란드 델프트 학파 회화에 나타난 동양풍 연구)

  • Kim, Myung-Eun;Bae, Soo-Jeong
    • Journal of the Korean Society of Costume
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    • v.65 no.8
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    • pp.136-150
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    • 2015
  • The purpose of this thesis is to elucidate the exchange between the East and the West during the 17th century through analyzing the oriental influences described in paintings in Delft school, a trade port of East India Company. The scope of this study focused on the 37 pieces of works by Johannes Vermeer and 31 pieces of the paintings by Pieter de Hooch, which are all the existing work, as analysis targets. The resources of this study were from previous papers about the history of costumes, paintings and culture, Internet sources and other qualitatively analyzed articles. The items that the study looked into were Delft porcelains and Delft tiles, Turkey carpets, costumes and accessories pearl earrings and headdresses. The study looked into oriental factors observed in each of these items, and analyzed them. In terms of oriental factors that are frequently observed in paintings, porcelains (100%), Deft tiles (100%), pearl earrings (100%) and (most) carpets (92.3%) turned out to have oriental nature, but this was not the case with head dresses (7.7%) and clothing (0.3%). These results happen to coincide with the previous investigation in that the oriental factor was reflected in the culture first, while the effects on costumes significantly lagged behind. This progress in cultural exchange can be seen through the noted use of Chinoiserie, a technique that is representative of the Chinese culture, in the 18th century. Through Japonism, the influence of Japanese culture into Europe was introduced, in detail, in 19th century. These results suggest that there are sufficient amount of sources that could be used to study the effect of orientalism to the Western culture. This study intends to look at how the oriental culture affected those of Europe by researching the Delft school of Netherlands during the 17th century.

A Study on Costume in Mural Painting of Xu Xianxiu Tomb in Northern Qi period (북제 서현수묘 벽화 복식 연구)

  • An, Bo Yeon;Hong, Na Young
    • Journal of the Korean Society of Costume
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    • v.66 no.1
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    • pp.122-134
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    • 2016
  • The Mural Tomb of Xu Xianxiu(AD 571), a high ranking official in Northern Qi period, is located in Taiyuan, Shanxi province, China. Despite having been raided, it was still discovered to contain over 530 pieces, such as artifacts and murals, in excellent state of preservation. These murals are noteworthy for their high level of detail compared to other murals from the same era, and are important for understanding the historical context of active East-West and Han-Hu cultural exchange in the $6^{th}$ to $7^{th}$ century. The murals of Xu Xianxiu's tomb depict round-collared and narrow-sleeved garments as well as straight collared robes typical of the Xianbei tribe's attire. Notable are the ermine fur overcoat and a headwear with flares on the left and right thought to be unique to the Xianbei. The wife and female servants show female attire of the Xianbei at the time; this attire can be characterized by narrow-sleeved long gowns and asymmetrical flying-bird buns. Despite the anti-Han policy of Northern Qi, influences such as the right sided gathering of the robes and embellished hair styles remain. The procession also depicts the three-cornered headdress and long-tailed hood of the Xianbei men, which have been recorded in documents. The large rounded pearl pattern containing the palmette, the divine animal, and bodhisattva's head motifs show the influence of the Western China [Xi'yu]. Considering that Northern Qi had more active interactions with the three ancient kingdoms of Korea than with the Southern Kingdoms[Nanchao], the findings of this study call for further research on the correlation between the attire of ancient Korea and Northern Qi.

COLOGNE BRAND PREFERENCES OF TEENAGERS IN THE PHILIPPINES: MANAGERIAL IMPLICATIONS

  • Ramirez, Roderick V.;Madamba, Jeanette Angeline B.;Tan, Reynaldo L.
    • Asia-Pacific Journal of Business
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    • v.6 no.2
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    • pp.19-33
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    • 2015
  • Studies focusing on the constantly changing buying behavior and product preferences of a booming teen market are rare and this is particularly true in the Philippines. To address this gap in the literature, this study focused on the supermarket brands of cologne preferred by teens in the Philippines such as Lewis & Pearl (L&P), Johnson's Baby Cologne, Juicy, Bench, Ellips, Fiona, Bambini and Baby Flo which are manufactured by various competing companies. Essentially, this study presented and described the profile and buying behavior of cologne users and non-cologne users and determined whether preferential differences existed between these brands. The respondents consisted of 473 teens all over the Philippines stratified in terms of general location via the three major groups of islands in the Philippines: Luzon, Visayas and Mindanao. Respondents came from selected schools in Quezon City in Metro Manila, Sariaya in Quezon Province, Cebu City, and Digos City to represent the Greater Metro Manila Area, Luzon, Visayas and Mindanao, respectively. Findings showed that almost all of the respondents used cologne at varying degrees. In general, teens use several scents and brands of cologne and continually shift from one scent/brand to another scent/brand. This made it difficult for any company to capture loyal consumers. The most popular brands used by teenagers were Bench (61.7%), Lewis and Pearl (59%), Juicy (42%), Afficionado (32%), Fiona (19.3%), Penshoppe (18%), Bambini (12.6%), Ellips (11.3%) and Zen Zest (7.5%). Fragrance or scent is the top priority of teenagers in choosing a cologne brand, followed by brand name, affordability, bottle design and endorser. The spray bottle type of colognes is preferred even if cologne spray bottles are priced higher than the splash cologne bottle type. Managerial implications of these findings for market players, marketing scholars and prospective investors are presented.

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An Adaptedness Assessment for Beach Nourishment Utilization of Dredged Materials in Hwasun-Port (화순항내 준설토사의 양빈재 유효활용을 위한 적합성 평가)

  • Choi, Jin-Hwan;Lee, Sang-Houck
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.4
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    • pp.2940-2944
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    • 2015
  • Dredged materials for effective use in Hwasun-port pollution analysis, Ni(nickel) in excess of the standard showed that the whole point. However, according to the revised standards effective utilization exceeds the reference value, even if no anthropogenic sources Pearl ratio less than 10% of the average weight of the ecotoxicological tests have passed, and if so it can be used to beach nourishment. Therefore, the average weight ratio of pearl and ecotoxicological tests were conducted by marine environment official test method. Mud to 5.37% of the average weight ratio lower than the reference value of 10% that was investigated. Ecotoxicity test using bioluminescent bacteria relative luminescence inhibition in the 0 to 9.13% with no toxicity was determined using benthic amphipods in the control and the test sample relative to the average survival rate is 0% with no toxicity was determined. Therefore, the revised effective use meets all the criteria that can be used to beach nourishment, so that the suitability was assessed.

Characterization of Streptomyces sp. KSM-35 and Purificaton of Its Maltotetraose Forming Amylase (Streptomyces sp. KSM-35의 특성과 Maltotetraose 생산성 아밀라제의 정제)

  • Cha, Jin;Kim, Young-Bae;Seo, Byung-Cheol;Park, Kwan-Wha
    • Korean Journal of Food Science and Technology
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    • v.26 no.5
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    • pp.633-637
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    • 1994
  • A bacterial strain KSM-35 producing maltotetraose forming amylase was isolated from compost and identified as Streptomyces based on its morphological, cultural, and physiological characteristics. The amylase from Streptomyces sp. KSM-35 culture filtrate was purified by ammonium sulfate precipitation, followed by the liquid chromatographic procedures using DEAE-Toyo pearl and sephadex G-100 with 27.1% activity recovery. The molecular weight of the enzyme was estimated to be 50,000 and the isoelectric point 4.3. The main product by the amylase from soluble starch was maltotetraose which accounted for 56% of all the oligosaccharides detected after 26 hrs of reaction. Maltose (20%o) and maltotriose (16%) were the next important byproducts while glucose and maltopentaose were detected as traces.

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Case Study on Measuring Technology Level Applying Growth Curve Model: Three Core Areas of Fishery Science and Technology (성장곡선 모형 적용을 통한 기술수준평가 사례 연구 : 특정 수산과학기술 분야를 중심으로)

  • Kim, Wan-Min;Park, Ju-Chan;Bark, Pyeng-Mu
    • The Journal of Fisheries Business Administration
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    • v.46 no.3
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    • pp.103-118
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    • 2015
  • The purpose of this paper is to discuss possibilities of applying growth curve models, such as Logistic, Log-Logistic, Log-Normal, Gompertz and Weibull, to three specific technology areas of Fishery Science and Technology in the process of measuring their technology level between Korea and countries with the state-of-the art level. Technology areas of hazard control of organism, environment restoration, and fish cluster detect were selected for this study. Expert panel survey was conducted to construct relevant panel data for years of 2013, 2016, and a future time of approaching the theoretical maximum technology level. The size of data was 70, 70 and 40 respectively. First finding is that estimation of shape and location parameters of each model was statistically significant, and lack-of-fit test using estimated parameters was statistically rejected for each model, meaning all models were good enough to apply for measuring technology levels. Second, three models other than Pearl and Gompertz seemed very appropriate to apply despite the fact that previous case studies have used only Gompertz and Pearl. This study suggests that Weibull model would be a very valid candidate for the purpose. Third, fish cluster detect technology level is relatively higher for both Korea and a country with the state-of-the-art among three areas as of 2013. However, all three areas seem to be approaching their limits(highest technology level point) until 2020 for countries with the state-of-the-art. This implies that Korea might have to speed up her research activities in order to catch up them prior to 2020. Final suggestion is that future study may better apply various and more appropriate models respectively considering each technology characteristics and other factors.