• Title/Summary/Keyword: Randomized CA Group

Search Result 32, Processing Time 0.028 seconds

Efficient Authentication for Mobile Nodes in Mobile Ad Hoc Network (Mobile Ad Hoc Network에서 이동 노드에 대한 효율적인 인증 메커니즘)

  • Lee Yong
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.42 no.11
    • /
    • pp.27-34
    • /
    • 2005
  • Mobile Ad Hoc Networks (MANETs) are self-organized networks that do not rely in their operation on wired infrastructure. As in any networking technology, security is an essential element in MANET as well, for proliferation of this type of networks. But supporting secure communication in MANETs proved to be a significant challenge, mainly due to the fact that the set of nodes in the network can change frequently and rapidly and due to the lack of access to the wired infrastructure. In particular, the trust model and the authentication protocols, which were developed for wired and infrastructure-based networks, cannot be used in MANETs. In this paper, we address the problem of efficient authentication of distributed mobile users in geographically large networks. In particular, we propose a new authentication scheme for this case of MANETs. The proposed scheme exploits Randomized Groups to efficiently share authentication information among nodes that together implement the function of a distributive Certification Authority (CA). We then evaluate the performance of authentication using Randomized Groups.

Numerical Analysis of Authentication Algorithm using Randomized CA Groups in Mobile Ad Hoc Networks (모바일 애드혹 네트워크에서 랜덤 CA 그룹을 이용한 인증 알고리즘에 대한 성능 분석)

  • Lee, Yong;Lee, Goo-Yeon
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.46 no.8
    • /
    • pp.22-33
    • /
    • 2009
  • Mobile Ad Hoc Networks (MANETs) are self-organized networks that do not rely in their operation on wired infrastructure. As in any networking technology, security is an essential element in MANET as well, for proliferation of this type of networks. But supporting secure communication in MANETs proved to be a significant challenge, mainly due to the fact that the set of nodes in the network can change frequently and rapidly and due to the lack of access to the wired infrastructure. In particular, the trust model and the authentication protocols, which were developed for wired and infrastructure-based networks, cannot be used in MANETs. In [1], we addressed the problem of efficient authentication of distributed mobile users in geographically large networks and proposed a new authentication scheme for this case of MANETs. The proposed scheme exploits randomized groups to efficiently share authentication information among nodes that together implement the function of a distributive Certification Authority(CA). In this paper, we analyze numerically the performance of authentication method using randomized groups and compare with the simulation result.

Bioavailability of Aspartic Acid Chelated Calcium in Calcium Deficient Rats (아스파르트산 킬레이트 칼슘의 칼슘 결핍쥐에서의 생물학적 유용성)

  • Park, Myoung-Gyu;Ha, Tae-Yul;Shin, Kwang-Soon
    • Journal of Nutrition and Health
    • /
    • v.44 no.6
    • /
    • pp.474-480
    • /
    • 2011
  • Calcium (Ca) is an essential element to maintain body homeostasis. However, many factors disturb calcium absorption. Aspartic acid chelated calcium (AAC) was synthesized by new methods using calcium carbonate and aspartic acid. This study was carried out to investigate the bioavailability of AAC in Ca-deficient rats. The experimental groups were as follows: NC; normal diet control group, CD-C; untreated control group of Ca-deficient (CD) rats, CD-$CaCO_3$; $CaCO_3$ treated group of CD rats, CD-AAC; AAC treated group of CD rats, and CD-SWC; and seaweed-derived Ca treated group of CD rats. The Ca content of various types of Ca was held constant at 32 mg/day, and the four CD groups were fed for 7 days after randomized grouping. Ca content in serum, urine, and feces within feeding periods were analyzed to confirm Ca absorption. Serum Ca content was significantly higher in the CD-AAC (11.24 mg/dL) and CD-SWC (10.12 mg/dL) groups than that in the CD-C (8.6 mg/dL) group 2 hours following the first administration. The Ca content in feces was significantly lower in the CD-AAC (35.4 mg/3 days) and CD-SWC (71.1 mg/3 day) groups than that in the CD-$CaCO_3$ (98.7 mg/3 days) group (p > 0.05). AAC had a 2.3-fold higher absorption rate of Ca than that of SWC. No differences in fibula length were observed in the NC and CD groups. The fibula weights of the CD-AAC (0.33 g) and CD-SWC (0.33 g) groups increased compared to those in the CD-C (0.27 g) group; however, no significant difference was observed between the CD groups. We conclude that bioavailability of AAC is higher than that of seaweed-derived Ca or inorganic Ca. Thus, these findings suggest the AAC has potential as a functional food material related to Ca metabolism.

Effect of Caffeine Administration on Energy Substrate Change During Submaximal Exercise (최대하 운동부하시 Caffeine의 투여가 운동선수의 혈중 Energy Substrate 변화에 미치는 영향)

  • 조홍관
    • Journal of Nutrition and Health
    • /
    • v.27 no.2
    • /
    • pp.162-171
    • /
    • 1994
  • The purpose of this study was to describe the effects of caffeine ingestion on the metabolic responses during submaximal exercise. Ten male of rowing player aged 18-22yrs. participated in the study. No subjects had any remarkable medical history and none were taking medications. According to the administration of dehydrated caffeine(CA) (6mg/kg) or placebo(PA), they were classified into two groups such as caffeine group and placebo group. A randomized, double-blind, crossover protocol was employed using either CA or PA. Subjects underwent a submaximal bicycle ergometer. Blood was drawn intravenously prior to 60 min., at rest, at 30, and 45 min. of exercise, and recovery period. Plasma concentrations of glucose, free fatty acid and lactate were obtained using enzymatic method. Followings were obtained by the tests and analyses; 1) Blood glucose(BG) of 45 minute of exercise was significantly decreased in CA group of 76.3$\pm$14.8 mg/100ml compared with PA group of 94.9$\pm$11.2 mg/100mg(p<0.5). 2) Free fatty acid(FFA) of 30minute of exercise was significantly increased in CA group of 720$\pm$80 $\mu$Eq/1 compared with PA group of 360$\pm$120 $\mu$Eq/1(p<0.5). After exercise, FFA was significantly higher in CA group than those in PA group(p<0.1). 3) Blood lactate(BL) was not significantly different between the two. After exercise, BL was significantly different in 30 minute(p<05).

  • PDF

Effects of Fresh Yellow Onion Consumption on CEA, CA125 and Hepatic Enzymes in Breast Cancer Patients: A Double-Blind Randomized Controlled Clinical Trial

  • Jafarpour-Sadegh, Farnaz;Montazeri, Vahid;Adili, Ali;Esfehani, Ali;Rashidi, Mohammad-Reza;Mesgari, Mehran;Pirouzpanah, Saeed
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.17
    • /
    • pp.7517-7522
    • /
    • 2015
  • Onion (Allium cepa) consumption has been remarked in folk medicine which has not been noted to be administered so far as an adjunct to conventional doxorubicin-based chemotherapy in breast cancer patients. To our knowledge, this is the first study aimed to investigate the effects of consuming fresh yellow onions on hepatic enzymes and cancer specific antigens compared with a low-onion containing diet among breast cancer (BC) participants treated with doxorubicin. This parallel design randomized controlled clinical trial was conducted on 56 BC patients whose malignancy was confirmed with histopathological examination. Subjects were assigned in a stratified-random allocation into either group received body mass index dependent 100-160 g/d of onion as high onion group (HO; n=28) or 30-40 g/d small onion in low onion group (LO; n=28) for eight weeks intervention. Participants, care givers and laboratory assessor were blinded to the assignments (IRCT registry no: IRCT2012103111335N1). The compliance of participants in the analysis was appropriate (87.9%). Comparing changes throughout pre- and post-dose treatments indicated significant controls on carcinoembryonic antigen, cancer antigen-125 and alkaline phosphatase levels in the HO group (P<0.05). Our findings for the first time showed that regular onion administration could be effective for hepatic enzyme conveying adjuvant chemotherapy relevant toxicity and reducing the tumor markers in BC during doxorubicin-based chemotherapy.

Acupuncture for Endometriosis; A Systemic Review (자궁내막증의 침치료 효과에 대한 체계적 문헌 고찰)

  • Kwon, Na-Yoen;Lee, Dong-Nyung
    • The Journal of Korean Obstetrics and Gynecology
    • /
    • v.34 no.2
    • /
    • pp.48-61
    • /
    • 2021
  • Objectives: This study was aimed to review the effect of acupuncture on endometriosis related pain in patients. Methods: Researchers searched data through 6 online databases up to November 2020. The data was limited to randomized controlled trial studies on endometriosis patients diagnosed with laparoscopy. Results: 7 Randomized controlled trials were included in this study. All of studies were published in Chinese, in China. Intervention of treatment group were composed of simple acupuncture and electroacupuncture. Intervention of control group were made up with mifepristone, herbal medicine and acupuncture. Outcome measurements were effective rate, serum Cancer antigen-125 (CA-125), Visual analogue scale (VAS)/pain score, and recurrence rate in 1 year. In all outcome measurements, treatment group were more effective than control group and it was statistically significant. Conclusions: Acupuncture therapy is effective in decreasing endometriosis related pain and preventing recurrence. However, because endometriosis is easy to recur, additional long-term research is needed.

Effect of Hominis Placenta Pharmacopuncture for a Patient with Mild Cognitive Impairment: A Randomized, Double-Blind, Placebo-Controlled, Multi-Center Trial

  • Kim, Yunna;Eom, Yoon Ji;Kwon, Dohyung;Lee, Jae Hyok;Jung, In Chul;Cho, Eun;Lee, Ji Eun;Cho, Seung-Hun
    • Journal of Oriental Neuropsychiatry
    • /
    • v.32 no.2
    • /
    • pp.81-93
    • /
    • 2021
  • Objectives: Mild cognitive impairment (MCI) is condition of cognitive decline shown in transition from normal aging to dementia. Hominis placenta pharmacopuncture (HPP) is a treatment that combines effects of medication and acupuncture by injecting Hominis placenta into acupoints. The objective of this study was to evaluate the efficacy and safety of HPP for MCI. Methods: This was a randomized, double-blind, placebo-controlled, two-center clinical trial. Eligible patients were randomly allocated to either the HPP group or the placebo group. HPP or saline as placebo was administered to participants for eight weeks. Changes in symptoms were observed. The primary outcome was difference in mean change of Korean Version of the Montreal Cognitive Assessment (MoCA-K) score between the HPP group and the placebo group. Cognitive function, overall status of mood and sleep, and quality of life (QoL) were also assessed. Safety assessment and economic analysis were then conducted. Results: Thirty participants were enrolled. One participant in the placebo group dropped out. The score of MoCA-K increased after treatment. Its mean change was smaller in the HPP group than in the control group. HPP ameliorated Global Deterioration Scale and Korean Dementia Rating Scale subtests for attention, organization, and memory compared to the placebo. However, none of them was significantly different between the two groups. Mood, sleep, and QoL all improved more in the HPP group than in the placebo group, although differences between the two groups were not statistically significant. There was no adverse event probably related to the drug. HPP treatment needed KRW 345,000 more than the placebo group in improving Geriatric Quality of Life scale-Dementia score by one point for one year. Conclusions: Although HPP treatment did not significantly improve cognition, it changed behavioral and psychological symptoms in MCI.

Fermented Laminaria japonica improves working memory and antioxidant defense mechanism in healthy adults: a randomized, double-blind, and placebo-controlled clinical study

  • Kim, Young-Sang;Reid, Storm N.S.;Ryu, Jeh-Kwang;Lee, Bae-Jin;Jeon, Byeong Hwan
    • Fisheries and Aquatic Sciences
    • /
    • v.25 no.8
    • /
    • pp.450-461
    • /
    • 2022
  • A randomized, double-blind, and placebo-controlled clinical study was used to determine the cognitive functions related to working memory (WM) and antioxidant properties of fermented Laminaria japonica (FLJ) on healthy volunteers. Eighty participants were divided into a placebo group (n = 40) and FLJ group (n = 40) that received FLJ (1.5 g/day) for 6 weeks. Memory-related blood indices (brain-derived neurotrophic factor, BDNF; angiotensin-converting enzyme; human growth hormone, HGH; insulin-like growth factor-1, IGF-1) and antioxidant function-related indices (catalase, CAT; malondialdehyde, MDA; 8-oxo-2'-deoxyguanosine, 8-oxo-dG; thiobarbituric acid reactive substances, TBARS) were determined before and after the trial. In addition, standardized cognitive tests were conducted using the Cambridge Neuropsychological Test Automated Batteries. Furthermore, the Korean Wechsler Adult Intelligence Scale (K-WAIS)-IV, and the Korean version of the Montreal Cognitive Assessment (MoCA-K) were used to assess the pre and post intake changes on WM-related properties. According to the results, FLJ significantly increased the level of CAT, BDNF, HGH, and IGF-1. FLJ reduced the level of TBARS, MDA, and 8-oxo-dG in serum. Furthermore, FLJ improved physical activities related to cognitive functions such as K-WAIS-IV, MoCA-K, Paired Associates Learning, and Spatial Working Memory compared to the placebo group. Our results suggest that FLJ is a potential candidate to develop functional materials reflecting its capability to induce antioxidant mechanisms together with WM-related indices.

Performance Comparison between Random CA Group Authentication and Home CA Authentication in Mobile Ad hoc Network (모바일 애드혹 네트워크에서 임의의 CA 그룹을 이용한 이동노드의 인증과 홈 CA를 이용한 인증방법의 성능 비교)

  • Lee, Yong;Lee, Goo-Yeon
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.45 no.10
    • /
    • pp.40-48
    • /
    • 2008
  • Security of self organized mobile ad hoc networks is an important issue because administration information in the networks is managed by the constituent nodes. Especially authentication mechanism is necessary for trust setup between newly joining nodes and the network. The authentication models and protocols which are based on the wireline infrastructure could not be practical for mobile ad hoc network. Although public key algorithm-based method is widely used for authentication, it is not easy to be applied to mobile ad hoc networks because they do not have infrastructure such as centralized CA which is needed for certificate verification. In this paper, we consider the public key based random CA group method proposed in [1] to provide efficient authentication scheme to mobile ad hoc networks and analyze the performance of the method, which is then compared to the home CA method. From the analysis results, we see that the random CA method where the function of CA is distributed to some mobile nodes and the authentication information is propagated to randomly chosen CAs shows higher reliability and lower cost than home CA method.

Cytoprotective action of Rubi Fructus by modulation of Reactive Oxygen Species, peroxynitrite and $Ca^{2+}$ (복분자(覆盆子)의 세포내 ROS, $ONOO^-$ 생성 및 $Ca^{2+}$ 증가 억제에 의한 혈관내피세포 보호작용)

  • Lee, Cheol-Woong;Jeong, Ji-Cheon
    • The Journal of Internal Korean Medicine
    • /
    • v.26 no.3
    • /
    • pp.615-625
    • /
    • 2005
  • Objectives : Poststroke depression is a frequent and specific entity that impaires the rehabilliation and functional recovery of patients with hemiplegia. The author evaluated the effect of Banhahubak-tang(Banxiahoupotang) in patients with poststroke depression. Methods : 38 patients suffering from poststroke depression(determined by Diagnostic and Statistical Manual of Mental Disorders, revised. 3rd edition. and Beck Depression Inventory[BDI] cutoff $point{\geqq}10$) in Kyunghee Oriental hospital were randomized into two groups; treatment group(n=19) and control group(n=19). The treatment group was prescribed with Banhahubak-tang(Banxiahoupotang) three times a day fur a week. Control troop was prescribed with other herbal medicines used for stroke Patients three times a day for a week. Patients were evaluated by use of BDI scale, Modified Barthel Index, Depression of Ki score, Yin syndrome score, and Yang syndrome score. Among 38 patients, 24 patients got BDI scores above 21, which is the cut-off score for depression in Korean. The same procedures and assessments described above were applied. Results : Treatment group did not significantly improve compared with control group. Results yielded only slight significance (P=0.086). Especially. patients with poststroke depression as yin syndrome improved more significantly on BDI than those classified as yang syndrome. When BDI cutoff point for depression was defined as being ${\geq}\;21$, treatment group did not significantly improve compared with control group(P=0.114). However, patients with poststroke depression classified as yin syndrome were also significantly improved on BDI than those classified as yang syndrome. Conclusions : This study suggests that Banhahubak-tang(Banxiahoupotang) is significantly effective in patients with poststroke depression classified as yin syndrome.

  • PDF