• Title/Summary/Keyword: Collector Method

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A Study on Level of Service of Sidewalk and Satisfaction of Pedestrian (보도의 서비스수준과 보행자 만족도에 대한 연구)

  • Kwon, Wantaeg;Kim, Sangyoup;Choi, Jaisung;Kim, Taeho;Jang, Youngsoo;Kim, Jinsub
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.15 no.3
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    • pp.129-145
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    • 2016
  • This paper analyzed and compared the service level and satisfaction of the sidewalks in collector roads from 6 different location, which has a lot of volume of pedestrians. For the study, it performed an investigation of road geometry, flow, research about satisfaction of walking and video recording. Based on this data, this study computed the service level of the sidewalks and pedestrian satisfaction. This study made a sense of correlation between service level and satisfaction. Also it focused on factors influencing on the effectiveness of satisfaction. This study also analyzed the change of walking behavior chracteristics according to the change of the level of satisfaction. This study adopted Multi-Modal Level of Service(MMLOS) method, because it could consider more factors. This study reached the conclusion that MMLOS method cannot completely reflect the level of pedestrian satisfaction. We have to consider more factors than in the current system for use in the development of sidewalk design. The result of this study is expected to reflect the pedestrian satisfaction in future sidewalks design.

Improving Haskell GC-Tuning Time Using Divide-and-Conquer (분할 정복법을 이용한 Haskell GC 조정 시간 개선)

  • An, Hyungjun;Kim, Hwamok;Liu, Xiao;Kim, Yeoneo;Byun, Sugwoo;Woo, Gyun
    • KIPS Transactions on Computer and Communication Systems
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    • v.6 no.9
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    • pp.377-384
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    • 2017
  • The performance improvement of a single core processor has reached its limit since the circuit density cannot be increased any longer due to overheating. Therefore, the multicore and manycore architectures have emerged as viable approaches and parallel programming becomes more important. Haskell, a purely functional language, is getting popular in this situation since it naturally supports parallel programming owing to its beneficial features including the implicit parallelism in evaluating expressions and the monadic tools supporting parallel constructs. However, the performance of Haskell parallel programs is strongly influenced by the performance of the run-time system including the garbage collector. Though a memory profiling tool namely GC-tune has been suggested, we need a more systematic way to use this tool. Since GC-tune finds the optimal memory size by executing the target program with all the different possible GC options, the GC-tuning time takes too long. This paper suggests a basic divide-and-conquer method to reduce the number of GC-tune executions by reducing the search area by one-quarter for every searching step. Applying this method to two parallel programs, a maximally independent set and a K-means programs, the memory tuning time is reduced by 7.78 times with accuracy 98% on average.

A New Strategy to Fabricate a Colloidal Array Templated $TiO_2$ Photoelectrode for Dye-sensitized Solar Cells

  • Lee, Hyeon-Jeong
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.05a
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    • pp.8.1-8.1
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    • 2011
  • Nanocrystalline titanium dioxide ($TiO_2$) materials have been widely used as an electron collector in DSSC. This is required to have an extremely high porosity and surface area such that the dye can be sufficiently adsorbed and be electronically interconnected, resulting in the generation of a high photocurrent within cells. In particular, their geometrical structures and crystalline phase have been extensively investigated as important issues in improving its photovoltaic efficiency. In this study, we present a new strategy to fabricate a photoelectrode having a periodic structured $TiO_2$ film templated from 1D or 3D polystyrene (PS) microspheres array. Monodisperse PS spheres of various radiuses were used for colloidal array on FTO glasses and two types of photoelectrode structures with different $TiO_2$ materials were investigated respectively. One is the igloo-shaped electrode prepared by $TiO_2$ deposition by RF-sputtering onto 2D microsphere-templated substrates. At the interface between the film and substrate, there are voids formed by the decomposition of PS microspheres during the calcination step. These holes might be expected to play the predominant roles as scattering spherical voids to promote a light harvesting effect, a spacious structure for electrolytes with higher viscosity and effective paths for electron transfer. Additionally the nanocrystalline $TiO_2$ phase prepared by the RF-sputtering method was previously reported to improve the electron drift mobility within $TiO_2$ electrodes. This yields solar cells with a cell efficiency of 2.45% or more at AM 1.5 illumination, which is a very remarkable result, considering its $TiO_2$ electrode thickness (<2 ${\mu}m$). This study can be expanded to obtain higher cell efficiency by higher dye loading through the increase of surface area or multi-layered stacking. The other is the inverse opal photonic crystal electrode prepared by titania particles infusion within 3D colloidal arrays. To obtain the enlargement of ordered area and high quality of crystallinity, the synthesis of titania particles coated with a organic thin layer were applied instead of sol-gel process using the $TiO_2$ precursors. They were dispersed so well in most solvents without aggregates and infused successfully within colloidal array structures. This ordered mesoporous structure provides the large surface area leading to the enough adsorption of dye molecules and have an light harvesting effect due to the photonic band gap properties (back-and-forth reflection effects within structures). A major advantage of this colloidal array template method is that the pore size and its distribution within $TiO_2$ photoelectrodes are determined by those of latex beads, which can be controlled easily. These materials may have promising potentials for future applications of membrane, sensor and so on as well as solar cells.

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A Study on a utilizing Mobile Mapping System for establishing the High Speed Outdoor Positioning DB based on Field Check Data (정위치 기반 고속 실외 측위 DB 구축을 위한 MMS활용 방안에 관한 연구)

  • Lee, Ha Dong;Lee, Yun;Choi, Yun Soo;Jeong, In Hun
    • Journal of Korean Society for Geospatial Information Science
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    • v.25 no.2
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    • pp.31-37
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    • 2017
  • Recently, governmental authority and local government are looking for a method of utilizing location information of smart phone for urgent rescue in fire and kidnap situation. Under this background, in this study, a method of rapidly collecting, constructing location determination based Wi-Fi AP data utilizing location information of smart phone and mobile mapping system was suggested in order to construct precise positioning information that could be utilized under urgent situation. By performing compensation work for GPS/INS/DMI through collected outcome, position of collected vehicle was acquired. In addition, source data integrating Wi-Fi information and collected position by coupling based on Wi-Fi AP collector and GPS time was constructed and Wi-Fi radiomap was constructed by removing Wi-Fi signal noise that reduces precise position performance. As a result of performing location determination performance assess ment by selecting 10 test positions by each local government, result value of 25.46cm for total local government average and 27.76m for SD could be obtained. It is considered that this result could be utilized as a technology of being able to supplement or substituting GPS location determination technology that is impossible in plocation determination of mobile communication company's base station (200m~2km) and indoor being used at present.

Dynamic Position Control Method for the Buffer Unit of a Deepsea Mining System (해석심해자원개발용 버퍼의 동적위치제어기법)

  • Kim, Ki-Hun;Choi, Hang-S.;Hong, Sup
    • Journal of the Society of Naval Architects of Korea
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    • v.39 no.3
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    • pp.57-63
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    • 2002
  • This paper describes a control algorithm for the buffer of a deep-sea mining system, in which the buffer is connected to a long slender pipe and then to a surface ship on one end, and to a collector on sea floor through a flexible hose on the other end. A mathematical modeling is established for designing the controller for buffer thrusters, in which the dynamic response of the long pipe is taken into account based on the mode superposition method. The fluid loading acting on the pipe is estimated by using Morison's formula. For simplicity, the surface ship is assumed to be kept stationary, the reaction from the flexible hose is ignored and only the lateral motions are considered. In order to guide the buffer to react only to the low-frequency motion of the surface vessel, the FIR digital filter is introduced to a PID-based controller It can be shown numerically that the high frequency component of the ship's motion can be effectively filtered out by using the FIR low pass filter.

Evaluation of Indoor Mold Exposure Level in dwelling Using DNA-Based Mold Assessment Method (DNA 기반 곰팡이 평가기법을 활용한 주택의 실내 곰팡이 노출수준 평가)

  • Hwang, Eun-Seol;Seo, Sung Chul;Lee, Ju-Yeong;Ryu, Jung-min;Kwon, Myung-Hee;Chung, Hyen-Mi;Cho, Yong-Min;Lee, Jung-Sub
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.28 no.4
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    • pp.382-392
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    • 2018
  • Objective: Allergic diseases such as asthma due to fungal exposure in houses have increased, and proper management is urgent. Mold can grow in the air, floor, walls, and other areas according to environmental conditions, and there are many limitations to the conventional methodology for examining fungal exposure. For this reason, the degree of fungal contamination is being evaluated by ERMI (Environmental Relative Moldiness Index), a quantitative analysis method proposed by the EPA. In this study, we compared ERMI values between water-damaged dwellings and non-damaged ones to evaluate the effectiveness of Korean ERMI values. We also explored the association of ERMI values with the level of airborne mold and characteristics of dwellings. Methods: Floor dust was collected after installing a Dustream collector on the suction port of a vacuum cleaner. The collected samples were filtered to remove only 5 mg of dust, and DNA was extracted using the FastDNA SPIN KIT protocol. Results: The ERMI values were found to be 19.6 (-6.9-58.8) for flooded houses, 7.5 (-29.2-48.3) for leaks/condensation, and 0.8 (-29.2-37.9) for non-damaged dwellings. The airborne concentration of mold for flooded, leakage or condensed, and non-damaged houses were $684CFU/m^3$, $566CFU/m^3$, and $378CFU/m^3$, respectively. The correlation between ERMI values and the levels of airborne mold was low (R = 0.038), but a weakly significant association of the ERMI values with the concentration of particulate matter ($PM_{10}$) was observed as well(R=0.231,P<0.05). Conclusions: Our findings show that the reference value using ERMI can be used to distinguish water-damaged and non-damaged dwellings. It is believed that ERMI values could be a promising tool for assessing long-term fungal exposure in dwellings.

Preparation and Electrochemical Properties of Freestanding Flexible S/CNT/NiO Electrodes for Li-S Batteries (리튬-황 전지용 프리스탠딩 플렉서블 S/CNT/NiO 전극의 제조 및 전기화학적 특성)

  • Shin, Yun Jung;Lee, Won Yeol;Kim, Tae Yun;Moon, Seung-Guen;Jin, En Mei;Jeong, Sang Mun
    • Korean Chemical Engineering Research
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    • v.60 no.2
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    • pp.184-192
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    • 2022
  • Porous NiO synthesized via hydrothermal synthesis was used in the electrodes of lithium-sulfur batteries to inhibit the elution of lithium polysulfide. The electrode of the lithium-sulfur battery was manufactured as a freestanding flexible electrode using an economical and simple vacuum filtration method without a current collector and a binder. The porous NiO-added S/CNT/NiO electrode exhibited a high initial discharge capacity of 877 mA h g-1 (0.2 C), which was 125 mA h g-1 higher than that of S/CNT, and also showed excellent retention of 84% (S/CNT: 66%). This is the result of suppressing the dissolution of lithium polysulfide into the electrolyte by the strong chemical bond between NiO and lithium polysulfide during the charging and discharging process. In addition, for the flexibility test of the S/CNT/NiO electrode, the 1.6 × 4 cm2 pouch cell was prepared and exhibited stable cycle characteristics of 620 mA h g-1 in both the unfolded and folded state.

A Study on Knowledge.Information Service with Electronic Culture Maps (전자문화지도를 활용한 지식정보서비스 연구 -조선족문화지도 중심으로-)

  • Kim, Dong-Hun;Kim, Sang-Hyeon;Moon, Hyun-Joo
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.1316-1320
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    • 2009
  • Since most information is readily available these days, the shear volume of the information simply overwhelms people, rather than helping them as a form of useful knowledge. Thus, the quantity of information someone owns doesn't possess much significance. The possibility to well-utilize the quality information is much more important these days. Electronic culture map service is being provided these days to introduce various cultural information to people around the world. But its service is limited to 'visualization, collection, and integration of the data.' Which means, electronic culture maps are no more than a simple data collector. The main purpose of this thesis is to develop a new kind of knowledge/information service method which overcomes these shortcomings. To achieve this goal, at first, the thesis will take a close look at the characteristics and functions of Chosunjock culture maps, and then, it will clarify the definition of data, information, knowledge of cultural resources. And secondly, nd thirdly, the thesis will look up the Wayfinding contents, User Experience Design, User Context, and Organic design for knowledge/information service. And lastly, the thesis will develop the knowledge/information service, specifically based on Chosunjock cultural resources.

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Identifying the Subjects of Nutrition Education for Junior and Senior High School Students (중.고등학생 대상 영양교육 현황 분석을 통한 영양교육 주제 도출)

  • Kang Yeo-Hwa;Yang Il-Sun;Kim Hye-Young;Lee Hae-Young
    • Journal of Nutrition and Health
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    • v.37 no.10
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    • pp.938-945
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    • 2004
  • The purposes of this study were to survey the present situation of nutrition education in junior/senior high school, to analyze the difference between the favorite subjects on students and the existing subject done by dietitians on nutrition education, and then to identify the subjects of nutritional education for junior/senior high school students. Self-administered questionnaires were given to dietitians and students and 142 of the 200 dietitians (71.0%) and 479 of the 564 students (84.9%) responded to the questionnaire on the nutritional education. According to the survey results, 76.1 % of school dietitians currently were doing nutrition education for students while the other 23.9% didn't have such education programs even though they recognized the necessity strongly. The target of nutrition education was student rather than parents or teacher generally and the principal measuring method for nutrition education effect was change of plate waste and leftover'. It was found that significant difference in the collector and source of nutritional education information between junior and senior high school dietitians (p< .05) . About ninety-eight percentage of dietitians felt that nutrition education should keep pace with meal service and this meant that almost respondent recognized the necessity of nutrition education for students. Because the most serious one among operational problems of nutrition education program was lack of enough time owing to too many affairs as dietitian, junior and senior high schools should support so that dietitians would share enough time for nutrition education. And also, a gap was existed between actual and favorite subjects on nutrition education. Significant differences existed in the following subjects; 'basic concept of food and nutrition', 'disease and nutrition', 'food culture in the world', 'cooking and culinary art', 'food of the 24 divisions of the year in the lunar calendar', 'food waste and environmental issue', 'food habit and food behavior', 'exercise and nutrition' (p< .001) 'table manner', 'food and individual sanitation', 'recommended dietary allowance' (p < .01) and 'menu planning' (p< .05) .Finally, 24 subjects of nutritional education were selected based on the survey results. These subjects would be expected to be able to contribute the effective and interesting nutrition education program for junior and senior high school students.

The Concept of Reproduction and the Criteria of an Exhibition in Contemporary Arts (현대미술에 있어서 '복제'의 개념과 전시규범의 문제 -${\gg}$살바도르 달리 탄생 100주년 특별전${\gg}$의 전시물 <성경> 연작을 중심으로)

  • Chang, Dong-Kwang
    • The Journal of Art Theory & Practice
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    • no.2
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    • pp.169-190
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    • 2004
  • The purpose of this article is to delve into the problems of originality of the artwork by examining issues of reproduction within the contemporary art market. In contemporary arts, especially in terms of art production and consumption, we can't overlook society and its economic structure and its connection with of capitalism. As the purity of art creation has turned into an exchange value, art, especially an object as artwork, has fallen into the status of production in an economic marketing system. Walter Benjamin mainly referred to that point in his thesis Das Kunstwerk im Zeitalter seiner technischen Reproduzierbarkeit, which originated the sociology of plastic arts. This thesis, published in 1936, traced how the artistic functions of photograph and movie had been changed through the social development. His main concerns were movie and photograph but what I am concentrating from his point of view, is that even in the field of plastic arts, the manufacture of reproduction has been practiced as a primary method within the social and political contexts and development. Though I am referring to this in the main body of this article, reproduction in contemporary art strongly needs a new definition since it has been spread all over like a newest virus, not only by collector's personal taste or hut also by commercial circulations of these reproductions to the public. This relates to Benjamin's argument about the value of an exhibition at a museum(Ausstellungswert). Since the function of an artwork has been one of cultural industry, the manufacturing of reproduction raises unexpected problems, such as, the originality of the artwork, the value of an exhibition at a museum, its achievement as documentary and as a territory of art criticism. In this point of view, I want to inquire into the value and criteria of an exhibition in contemporary art through the review of the definitions and the intrinsic attributes of reproduction. Somehow in a broad sense, the reproduction is a product coming out of representation or copy (replica) of an original art work or an model. Therefore, the problems it presents differ from the Simulacre, which is an image without an original one. In terms of the Meanings of reproduction, we can distinguish it as reproductions, copies, and productions. These types of reproductions are not the original artworks reflected by the creative intention of the artists. For example, a publishing company reproduced some of lithographs of Salvador Dali in the 1960s. They are commercial copies in the form of representation or reproduction with no artistic and creative intention of the artist. However, In despite of this theoretical basis, reproductions of the famous artists are still displayed without any verification for of the public's quest for the artworks. Moreover, many commercial companies that are planning to exhibit art works of the world-famous artists only for their profits keep trying to speak ill of and judging by the law the honest art critics' articles which discuss the true values of exhibition. If freedom of expression is one of the ideals of democracy, even the judgment of the originality of the artworks should be freely expressed.

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