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Protector Design and Shock Analysis for a Launch-Reconnaissance Robot (발사형 정찰로봇을 위한 보호체 설계 및 충격해석)

  • Kang, Bong-Soo;Park, Moon-Sik
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.8
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    • pp.971-976
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    • 2011
  • This paper presents the design concepts of a protector for a launch-reconnaissance robot that is to be deployed for data-collection in hazardous regions. The protector protects the reconnaissance robot inside from shock induced during the process of launch, flight, and landing. Since the outer shells of the protector are automatically opened wide by the unlocking mechanism during the landing stage, the reconnaissance robot can easily exit the protector and move around to carry out its mission. We carefully simulated a finite-element model of the protector with the robot and compared the results with the actual dynamic behavior of the system. Shock- response tests using a droptable showed that the proposed protector filled with silicon material successfully attenuated external shock.

Piglets' Surface Temperature Change at Different Weights at Birth

  • Caldara, Fabiana Ribeiro;dos Santos, Luan Sousa;Machado, Sivanilza Teixeira;Moi, Marta;de Alencar Naas, Irenilza;Foppa, Luciana;Garcia, Rodrigo Garofallo;de Kassia Silva dos Santos, Rita
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.3
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    • pp.431-438
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    • 2014
  • The study was carried out in order to verify the effects of piglets' weight at birth on their surface temperature change (ST) after birth, and its relationship with ingestion time of colostrum. Piglets from four different sows were weighed at birth and divided into a totally randomized design with three treatments according to birth weight (PBW): T1 - less than 1.00 kg, T2 - 1.00 to 1.39 kg, and T3 - higher than or equal to 1.40 kg. The time spent for the first colostrum ingestion was recorded (TFS). Images of piglets' surface by thermal imaging camera were recorded at birth (STB) and 15, 30, 45, 60, and 120 min after birth. The air temperature and relative humidity were recorded every 30 min and the indexes of temperature and humidity (THI) were calculated. A ST drop after 15 min from birth was observed, increasing again after sixty minutes. Positive correlations were found between the PBW and the ST at 30 and 45 min after birth. The PBW was negatively correlated with the TFS. The THI showed high negative correlations (-0.824 and -0.815) with STB and after 15 min from birth. The piglet's surface temperature at birth was positively correlated with temperature thereof to 15 min, influencing therefore the temperatures in the interval of 45 to 120 min. The birth weight contributes significantly to postnatal hypothermia and consequently to the time it takes for piglets ingest colostrum, requiring special attention to those of low birth weight.

An Analysis of Aerosols Impacts on the Vertical Invigoration of Continental Stratiform Clouds (에어로솔의 대륙 층운형 구름 연직발달(Invigoration)에 미치는 영향 분석)

  • Kim, Yoo-Jun;Han, Sang-Ok;Lee, Chulkyu;Lee, Seoung-Soo;Kim, Byung-Gon
    • Atmosphere
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    • v.23 no.3
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    • pp.321-329
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    • 2013
  • This study examines the effect of aerosols on the vertical invigoration of continental stratiform clouds, using a dataset of Atmospheric Radiation Measurement (ARM) Intensive Operational Period (IOP, March 2000) at the Southern Great Plains (SGP) site. To provide further support to our observation-based findings, the weather research and forecasting (WRF) sensitivity simulations with changing cloud condensation nuclei (CCN) concentrations have been carried out for the golden episode over SGP. First, cross correlation between observed aerosol scattering coefficient and cloud liquid water path (LWP) with a 160-minutes lag is the highest of r = 0.83 for the selected episode, which may be attributable to cloud vertical invigoration induced by an increase in aerosol loading. Modeled cloud fractions in a control run are well matched with the observation in the perspective of cloud morphology and lasting period. It is also found through a simple sensitivity with a change in CCN that aerosol invigoration (AIV) effect on stratiform cloud organization is attributable to a change in the cloud microphysics as well as dynamics such as the corresponding modification of cloud number concentrations, drop size, and latent heating rate, etc. This study suggests a possible cloud vertical invigoration even in the continental stratiform clouds due to aerosol enhancement in spite of a limited analysis based on a few observed continental cloud cases.

A Literature Study of Topical Application of Chinese Herbal Medicine for Allergic Rhinitis (국소한약외용제의 알레르기성 비염 치료 효과에 대한 문헌 고찰)

  • Bang, Mi Ran;Kim, Jang Hyun;Min, Sang Yeon
    • The Journal of Pediatrics of Korean Medicine
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    • v.30 no.3
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    • pp.52-60
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    • 2016
  • Objectives The purpose of this study is to analyze studies about the effects of topical application of Chinese herbal medicine for allergic rhinitis within randomized controlled trials (RCT). Methods The search database includes KJTK (Korean Traditional Knowledge Portal), OASIS (Oriental Medicine Advanced Searching Integrated system), CNKI (China National Knowledge Infrastructure), PubMed, and EMBASE. We used the following key search terms: "allergic rhinitis", "traditional Chinese medicine", "traditional Korean medicine", "Chinese herbal medicine", "randomized controlled trial", "clinical study", "nasal spray", and "nasal drop" Results Five studies were selected for analysis. Three studies used nasal spray of Chinese herbal medicine and two studies used nasal drops of Chinese herbal medicine for the intervention. Frequently used herbs were Magnoliae Flos (辛夷), Scutellariae Radix (黃芩), Coptidis Rhizoma (黃連), and Astragali Radix (黃芪). For the outcome measures, studies used symptom score, questionnaire of Quality of Life, nasal airway resistance, or laboratory studies. From all 5 studies, it has been shown that topical application of Chinese herbal medicine was effective for improving symptoms of allergic rhinitis. Two out of five studies showed statistical difference between study group and control group. Conclusions This study shows that topical application of Chinese herbal medicine can improve symptoms of allergic rhinitis. Well-designed RCT studies with low risk of bias and studies with outcome measures for assessing the immunomodulatory effects are necessary to confirm these findings.

A Research On the T-DMB Received Environment For the Efficient Reuse of the Band of VHF Frequency (VHF대역의 효율적 재활용을 위한 T-DMB 수신환경 조사)

  • Park, Sung-Kyu;Lee, Sang-Un;Chae, Su-Hyun;Park, Gooman
    • Journal of Broadcast Engineering
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    • v.21 no.5
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    • pp.726-738
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    • 2016
  • This study analyzed the properties of VHF band and suggested an efficient VHF band application plan for digital radio and UHDTV broadcasting through the experiment by the house T-DMB device in practical user environment. In order to find an efficient frequency band for digital radio broadcasting, this study examined first, to check the times of drop-out receive occurring in the audible area using a DMB/FM CAR Radio for T-DMB that has the characteristics of DAB. Second, this article explored the phenomenon of feedback loops in the same channel using a T-DMB house gap filler transmitting the signal by the same OFDM modulation scheme with UHDTV for configuring suitable SFN transmission network of the UHDTV broadcasting. Based on these experiments, this study suggested a suitable VHF band for digital radio and an efficient utilization of the VHF frequency band for the SFN network configuration of UHDTV.

Fast Handoff through Minimizing L2 Delay in Next Generation Mobile System (차세대 이동통신 시스템에서 L2 지연 감소를 통한 빠른 핸드오프)

  • Choi Hye-Eun;Kim Namgi;Yoon Hyunsoo
    • The KIPS Transactions:PartC
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    • v.11C no.7 s.96
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    • pp.1023-1032
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    • 2004
  • It is generally known that handoff delay degrades the QoS by packet drop, packet delay and jitter. Moreover. handoff highly effects on QoS in beyond 3G system because not only micro cells for achieving high capacity and fast moving nodes induce the frequent handoff but also hard handoff must be carried out in OFDM system. Therefore, study on a handoff algorithm for guaranteeing QoS is required. Related works on handoff for beyond 3G system mainly focused on reducing the L3 handoff delay or packet loss. That is, these schemes try to compensate L2 delay rather directly eliminate it. However, remained 1.2 delay degrades QoS, especially delay-sensitive realtime traffic. Therefore, we proposed the seamless handoff algorithmwhich can minimize the L2 handoff delay.

Regional variation in vertebral bone density and structure due to osteoporosis (골다공증에 따른 부위별 골 밀도와 구조의 변화)

  • Park, J.H.;Lee, S.J.;Chang, H.;Choi, W.S.;Kang, C.;Tack, G.R.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.169-170
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    • 1998
  • In this study, regional variation in vertebral bone density due to osteoporosis were investigated using a method that employs images from QCT. QCT images(1mm thick slices) of the first lumbar vertebra from a normal person (23/M, BMD=139.8mg/ml) and from an osteoporotic patient (54/F, BMD=82.0mg/ml) were obtained. Uniform settings (140kVp, 204mA) were used and images of 300 Hounsfield Unit or greater were selectied to filler out soft tissue interference. To assess the regional variation of the area fraction the vertebral body was divided into 3 layers and each layer contained 9 regions. Area faction was calculated based on image analysis data. Our results showed that the area fraction at the middle of the vertebra was quite lower than the endplate and peripheral regions, but the area fraction values from the osteoporotic patient were uniform throughout the entire height of the vertebral body, which indicates the significant drop of BMD had occurred near both end-plates due to the osteoporosis, especially at the peripheral regions. Our results suggest the susceptability of the vertebrae to compression fracture types in osteoporotic spine.

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Electrochemical Migration Characteristics of Sn-3.0Ag-0.5Cu Solder Alloy in NaBr and NaF Solutions (NaBr 및 NaF 용액에 대한 Sn-3.0Ag-0.5Cu 솔더 합금의 Electrochemical Migration 특성)

  • Jung, Ja-Young;Jang, Eun-Jung;Yoo, Young-Ran;Lee, Shin-Bok;Kim, Young-Sik;Joo, Young-Chang;Chung, Tai-Joo;Lee, Kyu-Hwan;Park, Young-Bae
    • Journal of Welding and Joining
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    • v.25 no.3
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    • pp.57-63
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    • 2007
  • Electrochemical migration characteristics of Pb-free solder alloys are quantitatively correlated with corrosion characteristics in harsh environment conditions. In-situ water drop test and corrosion resistance test for Sn-3.0Ag-0.5Cu solder alloys were carried out in NaBr and NaF solutions to obtain the electrochemical migration lifetime and pitting potential, respectively. Sn-3.0Ag-0.5Cu solder alloy shows similar ionization and electrochemical migration behavior with pure Sn because of Ag and Cu do not migrate due to the formation of resistant intermetallic compounds inside solder itself. Electrochemical migration lifetime in NaBr is longer than in NaF, which seems to be closely related to higher pitting potential in NaBr than NaF solution. Therefore, it was revealed that electrochemical migration lifetime of Sn-3.0Ag-0.5Cu solder alloys showed good correlation to the corrosion resistance, and also the initial ionization step at anode side is believed to be the rate-determining step during electrochemical migration of Pb-free solders in these environments.

A Study on the Optimal Clothing Weight in an Air Conditioned Office in Summer (여름철 냉방실내의 적정착의량에 관한 연구)

  • Kim Sun Young;Lee Soon Won
    • Journal of the Korean Society of Clothing and Textiles
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    • v.9 no.3
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    • pp.45-51
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    • 1985
  • The purpose of this study is to research into the thermal condition and the weight of clothes suitable for the officers engagged in light works in an air-conditioned room in summer. The Major findings are as follows: 1. Thermal conditions of the working environment are $24.5^{\circ}C$ (Dry bulb temp.), $68\%$ (Relative humidity) and 2.6m/sec (Air Velocity). 2. Total clothing weights are 416.6 g/$m^2$ (male) and 340.9 g/$m^2$ (female). Underwear weights are 96.8g/$m^2$ (male) and 85.1g/$m^2$ (female). The latter turned out to be statistically significant in Sexual difference. 3. Means of the thermal sensation are 3.0 (comfortable; male) 2.7 ('Slightly cool' -'Comfortable'; female) and the relationship between clothing weights and thermal sensation proves to be significantly correlated in the case of female. 4. $66.7\%$ of the women and $37.1\%$ of the men feel sensation of coldness at the body's specific area and $79.5\%$ of the women and $54.3\%$ of the men reveals air-conditioning disturbance. 5. As the thermal sensation is close to 'cool-cold', sensation of coldness or air conditioning disturbance are showed up more frequently which is reversely related with weight of under-wear. It is also proved that air conditioning disturbances are influenced by sexual difference in addition to sensation of coldness and thermal sensation. 6. According to the result of experiment, we can have the idea that at condition $X_1$, the drop of limbs' skin temp. is remarkable. At condition $X_2$ skin temp. for distal limbs and mean skin temp. are raised and the falling degree is similar. At condition $X_3$, mean skin temp. and distal skin temp. are remarkably raised, and the falling degree decreases and the beats of pulse rate increase and diastoric blood pressure is lowered.

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A Study on the Pattern Making of Men's Classic Jackets - For ages of the early in the twenties - (남성의 클래식 재킷원형에 관한 연구 -20대 초반의 남성을 중심으로-)

  • 이정임;남윤자
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.5
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    • pp.654-663
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    • 1998
  • The purpose of this study is to improve the classic jacket pattern for Korean young men whose chest circumference is 91~94cm, status is 170~175 cm, and drop value between chest and waist circumference is 15. The study was carried out by the following procedures. 1. Through the comparative investigation on the conventional classic jacket patterns of Hyung-sook Lee's, 문화's in Japan, and SMA's and the clothing experiment, the characteristics of every three patterns were found. 2. According to correct the unsuitable point in Hyung-sook Lee's pattern which was found more suitable than other two patterns and to refer to the product size of the ready-made classic jackets for men, the new suitable classic jacket pattern was achieved. 3. The sensory evaluation for appearance and comfort and one to one comparison was applied to evaluate the new classic jacket pattern by comparing with the Hyung-sook Lee' s jacket pattern. From the result of the sensory evaluation and one to one comparison, it was found that the new classic jacket pattern was more suitable for appearance and comfort. 4. From the result of this study, the suitable surplus of men's classic jacket at present is about 23~24cm on the chest circumference, 31~32 cm on the waist circumference, 14~15 cm on the hip circumference, 13~14 cm on the upper arm circumference, and 14 cm on the wrist circumference and the ease is about 3.5 cm on the armhole circumference. This size is not the absolute size but it helps to make the surplus in any other clothes for Korean young men.

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