• Title/Summary/Keyword: hard turning

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The Experience of Receiving Radioactive Iodine Therapy among Thyroid Cancer Patients (갑상선암 환자의 방사성요오드 치료경험)

  • Kang, Kyung Ok;Kim, Hyun Kyung;Kim, Ji Young;Lim, Seok Tae
    • Journal of East-West Nursing Research
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    • v.22 no.2
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    • pp.148-157
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    • 2016
  • Purpose: The purpose of this study was to explore the meaning of the experience of receiving radioactive iodine therapy among patients with thyroid cancer. Methods: A qualitative research design was adopted. The participants were ten women diagnosed with thyroid cancer who had received radioactive iodine therapy within one year. Data were collected through in-depth interviews from October of 2015 to April of 2016. Individual interviews were recorded, and transcribed data were analyzed using Colaizzi's method. Results: The six categories of the experience of receiving radioactive iodine therapy were "Finally realizing having cancer," "The lonely fight that feels like prison life," "Narrower scope of life," "Lack of understanding by others," "Enduring a short, yet difficult journey," and "A turning point for a new life." Conclusion: This study provides deep insight into the experience of thyroid cancer patients who had received radioactive iodine therapy. Nurses should concern their distress during radioactive iodine treatment and manage psychological difficulties as well as physical symptoms. Support from family and health care providers may help them to overcome the hard journey.

Optimization of Multi-tasking Vertical Lathe For Windmill Parts (풍력 발전기 부품가공용 복합수직선반의 최적 설계에 관한 연구)

  • Choi, Hag-Bong;Lee, Jong-Hoon;Park, Woo-Sang;Sin, Heung-Chul;Oh, Jong-Suk;Park, Chun-Hong;Lee, Dong-Yun
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.2
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    • pp.147-155
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    • 2012
  • Wind power, which is one of the promising renewable energies, has shown the high growth rate of 35 % of the annual average in the recent 5 years and also windmill related equipment market has been fast-growing. Yaw & Pitch bearing are the key parts of windmill and are machined by huge vertical lathe which is monopolized by the advanced countries. The purpose of this study is to develop the multi-tasking vertical lathe for 5 MW grade windmill bearings, which might be mass produced 3 or 5 years later. In this study, the structure of the crossrail and rotary table, which are the key units of the huge multi-tasking vertical lathe, were optimized through the finite element analysis. Also the basic performance of the rotary table has been evaluated.

Continuous Conduction Mode Soft-Switching Boost Converter and its Application in Power Factor Correction

  • Cheng, Miao-miao;Liu, Zhiguo;Bao, Yueyue;Zhang, Zhongjie
    • Journal of Power Electronics
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    • v.16 no.5
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    • pp.1689-1697
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    • 2016
  • Continuous conduction mode (CCM) boost converters are commonly used in home appliances and various industries because of their simple topology and low input current ripples. However, these converters suffer from several disadvantages, such as hard switching of the active switch and reverse recovery problems of the output diode. These disadvantages increase voltage stresses across the switch and output diode and thus contribute to switching losses and electromagnetic interference. A new topology is presented in this work to improve the switching characteristics of CCM boost converters. Zero-current turn-on and zero-voltage turn-off are achieved for the active switches. The reverse-recovery current is reduced by soft turning-off the output diode. In addition, an input current sensorless control is applied to the proposed topology by pre-calculating the duty cycles of the active switches. Power factor correction is thus achieved with less effort than that required in the traditional method. Simulation and experimental results verify the soft-switching characteristics of the proposed topology and the effectiveness of the proposed input current sensorless control.

Evaluation of Ultrasonic Vibration Cutting while Machining Inconel 718

  • Nath, Chandra;Rahman, Mustafizur
    • International Journal of Precision Engineering and Manufacturing
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    • v.9 no.2
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    • pp.63-68
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    • 2008
  • Hard and brittle materials, such as Ni- and Ti-based alloys, glass, and ceramics, are very useful in aerospace, marine, electronics, and high-temperature applications because of their extremely versatile mechanical and chemical properties. One Ni-based alloy, Inconel 718, is a precipitation-hardenable material designed with exceptionally high yield strength, ultimate tensile strength, elastic modulus, and corrosion resistance with outstanding weldability and excellent creep-rupture properties at moderately high temperatures. However, conventional machining of this alloy presents a challenge to industry. Ultrasonic vibration cutting (UVC) has recently been used to cut this difficult-to-machine material and obtain a high quality surface finish. This paper describes an experimental study of the UVC parameters for Inconel 718, including the cutting force components, tool wear, chip formation, and surface roughness over a range of cutting conditions. A comparison was also made between conventional turning (CT) and UVC using scanning electron microscopy observations of tool wear. The tool wear measured during UVC at low cutting speeds was lower than CT. UVC resulted in better surface finishes compared to CT under the same cutting conditions. Therefore, UVC performed better than CT at low cutting speeds for all measures compared.

Analysis and Simulation of New Soft Switching Buck-Boost Chopper (새로운 소프트 스위칭 벅-부스터 초퍼의 해석 및 시뮬레이션)

  • Ko, K.H.;Kwon, S.K.;Kwak, D.K.;Lee, Hyung-Woo;Lee, Hyun-Woo
    • Proceedings of the KIEE Conference
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    • 1998.07f
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    • pp.2036-2038
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    • 1998
  • In the buck-boost DC-DC chopper which is used at a certain situation such as in factories where loads often change a lot, the switches in the device make big energy loss in operating at Buck-Boost Mode due to hard switching and are affected by lots of stresses which decrease the efficiency rate of the converter. In order to improve this problem, to decrease the loss of snubber and switching, it has been investigated that zero voltage switching mode and zero current switching mode which make the operation of switches with soft switching. For the more sophisticated and advanced device, this paper is presented the Partial Resonant Soft Switching Mode Power Converter which is adapted the power converter having the partial resonant soft switching mode, that makes switches operate when the resonant current or voltage becomes zero by making the resonant circuit partially at turning on and off of the switches with suitable layout of the resonant elements and switch elements in the converter. Also, this paper includes the analysis and simulation of the Partial Resonant type Buck-Boost Chopper.

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A Fundamental Study on the Types of Ship and the Steerage of Purse Seiners (巾着網漁船의 船型과 操船의 基礎的 硏究)

  • 김진건
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.30 no.1
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    • pp.13-24
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    • 1994
  • Purse seiner detects a fish school navigating in full speed with the aid of fish finder, sonar, helicopter, etc., and casts a net quickly to enclose the fish school in purse seine net according to the movement of the fish school, wind, and current. At this moment, if the time of casting a net, direction, speed, and turning circle are net suitable, it is unavoidable to lose fish school founded with hard efforts and we only consume our efforts of casting and hauling the net. Therefore, in order to enclose the fish school to enhance the amount of fish for each casting, the author investigated the type of ships equipped with purse seiners and examined maneuvering tests so that we provide some basic information to figure out the ability of steerage correctly. The results obtained are summarized as follows: 1. Block coefficients of pelagic tuna purse seiners with gross tonnage between 500 and 1500 tons are recorded between 0.50 and 0.55 which are greater than those of off shore purse seiners recorded as between 0.44 and 0.54 and less than those of various cargo ships recorded as between 0.56 and 0.84. 2. L/B, L/D, B/D, B/T, and T/D of the class of gross tonnage between 75 and 130 tons are respectively 4.49, 11.00, 2.45, 2.85 and 0.86 as their average and those of the class of between 500 and 1500 tons are 4.89, 10.53, 2.15, 2.73 and 0.75 respectively, which are quite different from those of various cargo ships recorded as 6.0~7.5, 11.0~12.0, 1.6~2.0, 2.2~2.8 and 0.65~0.75 respectively. 3. Rudder area ratio of purse seiners of the class of between 75 and 130 tons is 1/24~1/31 and that of the clase of between 500 and 1500 tons is 1/36~1/42 which is greater than that of various cargo ships recorded as 1.45~1.75. 4. On speed-length ratio of purse seiners. 111 Dong-a has the biggest value 2.94 the class of 130 tons has 2.52 the class of between 75 and 100 tons has 2.30~2.35 and the class of between 500 and 1500 tons has 1.99~2.05. 5. Turning circle of stern trawlers Pusan 404 and Haelim 3 are measured as below according to rudder angles 5$^{\circ}$, 15$^{\circ}$, 25$^{\circ}$ and 35$^{\circ}$ respectively. Advances are 11.3~13.6, 6.0~7.1, 3.6~4.8 and 2.5~3.5 times of LPP respectively. Tactial diameters are 15.2~18.6, 6.9~8.0, 4.2~4.9 and 2.9~3.5 times of LPP. Purse seiner 111 Dong-a with rudder angle 35$^{\circ}$ has a good yaw with quick responsibility since its advance is 2.2~2.3 times of LPP and since its tactial diameter is 2.0~2.1 times of LPP. 6. In full ahead going of purse seiner 111 Dong-a, it takes about 2 minutes and 10.6 times of LPP from the reverse turning its engine into full astern to the ship speed 0. In its full astern going, it takes about 1 minute and 5.1 times of LPP from the reverse turning its engine into full ahead to the ship speed 0. In its full ahead going, it takes about 2 minutes and 50 seconds and 12.3 times of LPP from stopping its engine to the dead slow ahead speed 3.2 knots.

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A Study on Man's Boots of the Joseon Dynasty (조선시대 남자용 화에 관한 연구)

  • Kwak Kyung-Hee;Hong Na-Young
    • Journal of the Korean Society of Costume
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    • v.56 no.1 s.100
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    • pp.44-55
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    • 2006
  • The purpose of this study is to examine the characteristics of man's boots in the Joseon Dynasty and compared them with those of the Ming and Qing Dynasty to find the influential relationships between them. Boots in the Joseon Dynasty are divided into several kinds such as Heukgwejapihwa, Hheuksapihwa(黑斜皮靴), Heukpihwa(黑皮靴), Mokhwa(木靴), Hyeopgeumhwa(挾金靴), Suhwaja (水靴子), Jeonpihwa, Gijahwa(起子靴), and Baekhwa(白靴). In addition, Jeong(精: footwear) was put inside boots. They tend to be named according to their materials or ornaments on them. First, Jeong put inside the boots is regarded as footwear for the comfort of the feet or protection against cold. Mokhwa appears in literature around the 19th century. As shown by remains and paintings of those days, it is considered to have become the common name of boots as it underwent many changes. On the other hand, a book in the era of King Gojong includes pictures of Suhwaja. Compared to Hukpihwa in the same book. The topside seems to have been raised in order to make the wearer who put on a military uniform feel comfortable when walking, since the bottom piece is hard. Baekhwa is worn not only with funeral garments but also with Sibok(時服), one of official uniforms. Boots in the Joseon Dynasty had been made following the design of the Ming Dynasty since official uniforms were conferred upon King Gongmin in the late Koryo Dynasty. But turning the late Joseon Dynasty its detailed design changed little by little. The topside of the boots became more round, the entrance part became wider, height of the shoes became taller, and the bottom piece became parallel to the ground.

Sales Strategies for Eggs and Special Brand Eggs in Japan II. Structure of Production Market Strategy of Special Brand Eggs (일본의 계란 판매전략과 특수란 II. 특수란의 생산과 판매대응)

  • 장경만
    • Korean Journal of Poultry Science
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    • v.26 no.1
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    • pp.43-50
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    • 1999
  • The features of special brand eggs are growing more and more diverse and it is hard to draw a clear distinction between these and ordinary (no-brand) eggs. Special brand eggs range from those with objectively recognizable characteristics to those given only an unsubstantial product image and price differentials are among them great, too. The relation between product features and prices is unclear. Special brand eggs are the commodity whose characteristics are the vaguest of all livestock products. Farm's brand eggs produce a high profitability to producers is they are directly sold to consumers, by, for example, home-delivery service. But if they are sold to supermarkets, etc., producer's (poultry farmer's) income becomes lower by the amount of distributors' margin, reducing the profitability substantially. Thus how to increase the ration of retailing is important for farmers to secure a high profit. The sales strategies of poultry are the combination of two elements, that is, new product development (product differentiation) and creation of new market. But it is difficult for special brand egg producers to develop products with clear characteristics (use value) distinct form ordinary eggs and so these producers depend on the factors of appearance, such as the color of egg shells and package. Special brand eggs manage to keep their marketable value by the combination of the few product features and product image. Thus NB eggs from feed producers have a great market-ability since they can take advantage of the power of patents and TV commercials. However, market differentiation affects profitability much more than product features and price gaps are very wide between directly sold and wholesaled eggs. The producers of special brand eggs have come to the turning point where they have to decide whether they will content with being the subcontractors for NB and PB eggs or they will continue to keep their independence in production and marketing.

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Establishment Construction Enterprise Resource Planning(ERP) & Construction Information Sttategy (건설정보화 전략과 ERP구축)

  • Lee Min-Nam;Oh Dong-Hwan
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.164-170
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    • 2003
  • This paper is to evaluate the informational direction, current situations and ERP establishment concerning constructing industry, to present the right directions, implemented cases for implementing constructional ERP, also to suggest the effect, influence, problems and shootings in constructional ERP arena. The constructing industries in korea are facing great turning point because of the huge corruptions currently happened and forcing to open the market in 1997. Attempting to establish Computer Integrated construction system (ERP) by breaking down constructing cost, improving quality, operating rapid and effective construction to enhance productivity, it is hard to achieve the goal with only inter-contractor's establishment. Constructing industries are integrated ones, consisted of many organizations for instance ordering agencies, contractors, subcontractors, material vendors, etc. and use various information formats such as texts, graphics, drawings. I dare suggest that implementation of constructional CALS including EDI/EC, GIS is tile only solution to control the information systematically generated in whole stages from planing, designing, constructing through maintenance, and to supply or switch the information.

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Development and distribution of geo-hazards triggered by the 5.12 Wenchuan Earthquake in China

  • Runqiu, Huang;Weile, Li
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.1225-1234
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    • 2009
  • As the Wenchuan Earthquake was of high magnitude and shallow seismic focus, it caused great damage and serious geo-hazards. By the field investigation and remote-sensing interpretation after the earthquake and by using means of GIS, the distribution of geo-hazards triggered by the earthquake was analyzed and the conclusions are as follows: (1) the earthquake geo-hazards showed the feature of zonal distribution along the earthquake fault zone and linear distribution along the rivers; (2) the distribution of earthquake geo-hazards had a marked hanging wall effect, for the development density of geo-hazards in the hanging wall of earthquake fault was obviously higher than that in the foot wall and the width of strong development zone in the hanging wall was about 10 km; (3) the topographical slope was a main factor which controlled the development of earthquake geo-hazards and a vast majority of geo-hazards were distributed on the slopes of 20 to 50 degrees; (4) the earthquake geo-hazards had a corresponding relationship with the elevation and micro-landform, for most hazards happened in the river valleys and canyon sections below the elevation of 1500 to 2000 m, particularly in the upper segment of canyon sections (namely, the turning point from the dale to the canyon). Thin ridge, isolated or full-face space mountains were most sensitive to the seismic wave, and had a striking amplifying effect. In these areas, collapses and landslides were most likely to develop; (5) the study also showed that different lithologies determined the types of geo-hazards, and usually, landslides occurred in soft rocks, while collapses occurred in hard rocks.

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