• ETRI Journal
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• 제39권2호
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• pp.213-221
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• 2017

The advent of wireless access in vehicular environments (WAVE) technology has improved the intelligence of transportation systems and enabled generic traffic problems to be solved automatically. Based on the IEEE 802.11p standard for vehicle-to-anything (V2X) communications, WAVE provides wireless links with latencies less than 100 ms to vehicles operating at speeds up to 200 km/h. To date, most research has been based on field test results. In contrast, this paper presents a numerical analysis of the V2X broadcast throughput limit using a path loss model. First, the maximum throughput and minimum delay limit were obtained from the MAC frame format of IEEE 802.11p. Second, the packet error probability was derived for additive white Gaussian noise and fading channel conditions. Finally, the maximum throughput limit of the system was derived from the packet error rate using a two-ray path loss model for a typical highway topology. The throughput was analyzed for each data rate, which allowed the performance at the different data rates to be compared. The analysis method can be easily applied to different topologies by substituting an appropriate target path loss model.

• 한국통신학회논문지
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• 제38C권2호
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• pp.165-171
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• 2013

차량 통신 프로토콜은 IEEE 802.11 WG과 P1609에서 진행하고 있는 WAVE(Wireless Access in Vehicular Environments)가 대표적이며, 보안 등을 제외한 MAC과 PHY에 대한 부분은 표준으로 제정되었다. 이러한 차량통신을 이용하여 운전자들의 안전과 전체 교통 흐름의 원활한 통제를 위해 국내외에서 많은 프로젝트가 진행되고 있다. 따라서 본 논문에서는 교차로에서 좌회전 시도 시에 위험 상황이 예상되면 운전자에게 알려주기 위한 차량간 통신 기반 안전서비스 알고리즘을 설계하였고, 이를 실제 구현하였다. 제안하는 알고리즘은 자차와 반대편에서의 접근차량에 대한 모델을 구성하고 충돌 위험이 있을 경우 운전자에게 HMI(Human Machine Interface)를 통해 경고를 주게 된다. 본 안전 서비스의 성능 테스트를 위해 테스트 차량을 이용하여 알고리즘을 시스템에 탑재하였으며, 테스트 케이스를 구성하여 성능 시험장에서 검증하였다. 테스트 결과로써, 우수한 성능을 나타냈으며, 앞으로 차량 통신 인프라가 설치된다면 V2I(Vehicle to Infrastructure) 통신을 이용하여 본 알고리즘을 보다 정밀하게 보완해야 할 것이다.

• Restorative Dentistry and Endodontics
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• 제25권4호
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• pp.527-535
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• 2000

The purpose of this study was to evaluate effects of smear layer and dentin primers on the sealing ability of root canals. 126 extracted human teeth with single, straight canals and mature apices were used. The Samples were first classified into six groups as follows: presence of smear layer; absence of smear layer; Scotchbond Bond Multi-Purpose; All Bond 2; Mac Bond 2; Clearfil Liner Bond 2. A Positive control was also established. All teeth except the control group were then obturated with thermoplasticized gutta-percha and AH26. Electrochemical and dye penetration technique were later used to evaluate the degree of micro leakage through the root canal. Seventy teeth were then immersed in a 1% potassium chloride solution and An external power supply(DC 10 V) was then applied to the circuit for the electrochemical microleakage test. The degree of Microleakage was determined over period of 28 days before being evaluated. In total, 48 teeth were submitted to the dye infiltration technique. All specimen were suspended in 2% methylene blue dye for 1 week before being longitudinally split. The degree of dye infiltration was measured under a stereo microscope at ${\times}10$ magnification and evaluated. The results were as follows: 1. Apical microleakage increased throughout the test period in all group and one group having a smear layer showed a dramatic increase under electrochemical test (p<0.05). In the group having smear layer, the degree of apical microleakage was the highest, and the micro leakage was much higher than in the smear layer removed group in electrochemical test (p<0.05). Scotchbond Multi-Purpose, All Bond 2, Mac Bond 2 and Clearfil Liner Bond 2 showed lower micro leakage than one group having smear layer. The All Bond 2 and Clearfil Liner Bond 2 treated groups showed the lowest microleakage in electrochemical test (p<0.05). 2. There was no significant difference between the experimental groups in dye penetration technique. These results suggested that the removal of the smear layer from root canal and concomitantly the application of dentin primer into root canal could improve the sealing ability of root canal obturation.

• 대한지역사회영양학회지
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• 제3권3호
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• pp.341-348
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• 1998

This study was performed to investigated the difference in the nutritional status of normal children and children with suboptimal iron status. Two hundred and sixty children from 5th grade were divided into 2 groups(normal group and suboptimal group) according to the hematologic parameters of iron(RBC count, hemoglobin, serum ferritin). Normal group was composed of 71 male and 81 female and suboptimal group was consisted of 65 male and 43 female. Fat percentage of children from suboptimal group was 18.9%, which was significantly lower than 22.1% of normal group(p<0.05). TST and MAC of suboptimal group were also lower than those of normal group(p<0.05). Mean intakes of energy, protein, thiamin, riboflavin, iron were lower than those in normal group(p<0.05). suboptimal female students showed 1197.6㎉ of energy intake(63.0% of RDA) and 0.56㎎ of thiamin intake(56% of RDA). Mean RBC count, hematocrit, hemoglobin, ferritin(p<0.01) and FEP(p<0.05) of suboptimal group were lower than those of normal group. Thirty-nine point seven percent of children from suboptimal group was observed with having gastrointestinal disease which was significantly higher than 22.1% of normal group. (Korean J Community Nutrition 3(3) : 341∼348, 1998)

• Journal of Animal Science and Technology
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• 제62권2호
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• pp.263-275
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• 2020

Studies on promoting milk protein yield by supplementation of amino acids have been globally conducted. Nevertheless, there is a lack of knowledge of what pathways affected by individual amino acid in mammary epithelial cells that produce milk in practice. Phenylalanine (PHE) and valine (VAL) are essential amino acids for dairy cows, however, researches on mammary cell levels are still lacking. Thus, the aim of this study was conducted to evaluate the effects of PHE and VAL on milk protein synthesis-related and energy-mediated cellular signaling in vitro using immortalized bovine mammary epithelial (MAC-T) cells. To investigate the effects of PHE and VAL, the following concentrations were added to treatment medium: 0, 0.3, 0.6, 0.9, 1.2, and 1.5 mM. The addition of PHE or VAL did not adversely affect cell viability compared to control group. The concentrations of cultured medium reached its maximum at 0.9 mM PHE and 0.6 mM VAL (p < 0.05). Therefore, aforementioned 2 treatments were analyzed for proteomics. Glucose transporter 1 and mammalian target of rapamycin mRNA expression levels were up-regulated by PHE (166% and 138%, respectively) (p < 0.05). Meanwhile, sodium-dependent neutral amino acids transporter type 2 (ASCT2) and β-casein were up-regulated by VAL (173% in ASCT2, 238% in and 218% in β-casein) (p < 0.05). A total of 134, 142, and 133 proteins were detected in control group, PHE treated group, and VAL treated group, respectively. Among significantly fold-changed proteins, proteins involved in translation initiation or energy metabolism were detected, however, expressed differentially between PHE and VAL. Thus, pathway analysis showed different stimulatory effects on energy metabolism and transcriptional pathways. Collectively, these results showed different stimulatory effects of PHE and VAL on protein synthesis-related and energy-mediated cellular signaling in MAC-T cells.

• Radiation Oncology Journal
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• 제18권3호
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• pp.194-199
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• 2000

목적 :직장암의 림프액 배액의 주된 경로는 종양의 위치가 항문환에 근접한 경우를 제외하고는 근위부플 향하므로 수술 후 방사선치료의 조사영역을 결정함에 있어서 전통적인 방법에 따를 경우 하부 골반강과 회음부에 불필요한 방사선조사를 하게될 수 있다. 본 연구는 하전방 절제술을 시행받은 직장암 환자에서 방사선치료 조사영역의 하연을 전통적인 방법에 의하지 않고 수술 문합부로부터 2 cm 내지 3 cm 하방으로 환자 개별적으로 결정하는 경우에 있어서 치료 실패의 양상이 어떠한 영향을 받는가를 알아보기 위하여 수행하였다. 대상 및 방법 : 1994년 9월부터 1998년 5월까지 성균관의대 삼성서울병원에서 근치적 하전방 절제술과 수술 후 방사선치료를 시행한 Modified Astler-Coiler (MAC) 병기 B2에서 C3까지인 88명의 직장암 환자를 대상으로 하였다. 남녀 환자 수는 각각 설명씩이었으며 연령의 중앙값은 57세(32-81세)였다. 2명의 환자를 제외한 모든 환자에서 저용량의 5-fluorouracil을 포함한 항암 화학요법을 병용하였으며, 수술 후 방사선치료는 6, 10, 15 MV X-ray를 이용하여 후전-좌우 대향의 3문 조사법으로 전골반부에 45 Gy와 종양 병소부위에 6 Gy를 5.5주간 걸쳐서 조사하였다. 연구 기간 초기의 16명의 환자에서는 전통적인 방사선조사영역 결정법을 적용하여 폐색공 하단, 또는 수술 문합부의 2 cm 내지 3 cm 하방 중에서 보다 낮은 쪽을 방사선조사영역의 하연으로 정하였으며, 나머지 72명의 환자에서는 수술 문합부에서 2 cm 내지 3 cm 하방에서 조사영역 하연을 개별적으로 결정하였는데 이와 같은 개별화된 방사선 치료 조사영역의 결정으로 55명(76$\%$)의 환자에서 방사선치료 조사영역 부피를 감소시킬 수 있었다. 이 두 군에 대해 생존율, 국소 종양 억제율, 무병생존율을 조사하여 비교하였고 예후 인자의 유의성을 조사하였다. 결과 : 추적 관찰 기간은 7개월부터 58개월이었으며, 중앙 추적기간은 27개월이었다. MAC 병기로 구분 시 B2가 32명(36$\%$), B3가 2명($2\%$), Cl이 2명($2\%$), C2가 50명($57\%$), C3가 2명($2\%$) 이었다. 전체 환자의 2년과 4년 생존율은 각각 $94\%$와 $68\%$였으며, 2년과 4년 무병 생존율은 각각 $86\%$과 $58\%$였다. 첫 치료 실패로서 국소 재발이 4명, 원격전이가 14명, 그리고 국소 재발과 원격전이가 동시에 있는 경우가 1명이었다. 방사선치료 조사영역의 하연 결정을 전통적인 방법을 적용한 군과 수술 문합부의 위치에 따라서 환자 개별적으로 결정한 군을 비교하여 볼 때 국소 종양 억제율과 무병 생존율은 각각 유의한 통계적인 차이를 보이지 않았다(p=42, p=68). 종양 색전자의 존재는 생존율, 국소 종양 억제율, 무병 생존율에 각각 영향을 미치는 유의한 위험인자로 관찰되었다. 결론 : 하전방 절제술을 시행받은 직장암 환자들의 수술 후 방사선치료 조사영역의 하연을 결정함에 있어서 각환자들의 병소 위치에 따라 개별적으로 결정하는 방법은 전통적인 하연 결정방법에 비하여 국소 종양 억제율과 무병생존율에 있어서 동등한 결과를 얻을 수 있었으며, 방사선치료 조사영역의 부피를 줄여 줌으로써 불필요한 방사선치료 부작용과 후유증의 감소를 얻을 수 있을 것으로 판단된다.

• KSBB Journal
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• 제5권2호
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• pp.113-118
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• 1990

생체내 중요한 면역조절물질의 하나인 IL-l은 주로 Macrophage로부터 분비되어 각종 면역반응에 관여하는 것으로 알려져 있는데 이러한 Macrophage에 의한 IL-I 생성에 미치는 Histamine의 효과를 검토하고자 Mac-rophage-like cell line인 $P388D^1$세포에 의한 IL-1생성에 미치는 Histamine의 첨가효과는 $10^-^8M~10^-^3M$에 이르기까지 전 범위에서 농도의존적으로 IL,-1생성을 촉진시켰으며 첨가후 배양시간에 있어서는 24~36시간이 가장 크게 상승되었다. Histamine에 의한 Macropahge로 부터의 IL-1생성은 EGTA 및 $Co^2^+$의 첨가로 인하여 농도의존적으로 저하되었으며 이 결과는 Histamine의 IL-1 생성촉진작용이 세포내로의 $Ca^2^+uptake가 signal 역할을 하고 있음을 시사한다. $P388D_1$세포로의 $Ca^2^+$uptake양을 동정한 결과는 Histamine의 $10^-^7M$에서 $10^-^3M$까지 농도의존적으로 $Ca^2^+3M$유입이 촉진되는 결과를 나타내었다.

• PNF and Movement
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• 제16권1호
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• pp.105-113
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• 2018

Purpose: The aim of this study was to explore the effects of dynamic balance training on pain, physical function, and dynamic balance in individuals with knee osteoarthritis. Methods: Fourteen patients with knee osteoarthritis participated in this study. The patients were randomly assigned to two groups: an experimental group (n=7) or a control group (n=7). All the patients took part in a lower extremity strength program for 30 min. In addition, the experimental group participated in a 30-min dynamic balance program. Both groups performed the program five times a week for 3 weeks. Outcomes, including the numeric rating scale (NRS), Western Ontario and MacMaster Universities Arthritis Index (WOMAC), and Community Balance and Mobility Scale (CB&M), were measured at baseline and after 3 weeks. Results: Both groups showed pre-to-post intervention improvements on all outcome measures (p<0.05). The experimental group showed a significant improvement in WOMAC (p = 0.00; Z = -2.82) and CB&M (p = 0.03; Z = -2.20) scores after the intervention as compared with those of the control group. Conclusion: The results revealed that dynamic balance training improved physical function, as well as balance ability, in patients with knee osteoarthritis as compared with that of a control group with no balance training.

• 대한한의학회지
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• 제28권2호통권70호
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• pp.224-240
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• 2007

Objectives : This study was carried out to investigate the effect of Jiyu-tang on gastric and ileac mucosal ulcer induced by indomethacin in mouse. Methods : The normal group was that no inflammation elicited mouse. Control group is that water administered mouse after gastro-inflammation elicitation. Sample group is that Jiyu-tang administered mouse after gastro-inflammation elicitation. Results : In the common morphology and histochemical change, control group were observed various injury by hemorrhagic erosion, while sample group was noticeably decreased than control group. In the immunohistochemical change, the distributions of COX-1 treated with Jiyu-tang noticeably increased than control group(p<0.05). The distributions of COX-2, MAC 387 and HSP-70, PCNA and TUNEL treated with Jiyu-tang noticeably decreased than control group(p<0.05). Conclusions : According to the above results, it is supposed that Jiyu-tang is applicable to gastric and ileac mucosal ulcer.

• Journal of Oral Medicine and Pain
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• 제21권2호
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• pp.255-264
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• 1996

This study was performed to demonstrate the method of image reformation for dental implants, using a personal computer with inexpensive softwares and to compare the images reformatted using the above method with those using Dentascan software. CT axial slices of 4 mandibles of 4 volunteers from GE Highspeed Advantage(GE Medical systems, U.S.A.) were used. personal computer used for image reformation was PowerWave 604/120 (Power computing Co, U.S.A. ) and softwares used were Osiris (Univ. Hospital of Geneva, Switzerland) and ImportACLESS Vl.1 (Designed Access Co., U.S.A.) for importing CT images and NIH image 1.58 (NIH, U.S.A.) for image processing. Seven image were selected among the serial reconstructed cross-sectional images produced by Dentascan. Seven resliced cross-sectional images at the same position were obtained at the personal computer. Regression analysis of the measurements of PC group was done against those of DS group. Measurements of the bone height and width at the reformer cross-sectional images using Mac-compatible computer was highly correlated with those using workstation with Dentascan software(height : r2= 0.999, p<0.001, width : r2= 0.993, p <0.001). So, it is considered that we can use a personal computer with inexpensive software for the dental implant planning, instead of the expensive software and workstation.