Utilizing OpenFlow and sFlow to Detect and Mitigate SYN Flooding Attack

Nugraha, Muhammad,Paramita, Isyana,Musa, Ardiansyah,Choi, Deokjai,Cho, Buseung Korea Multimedia Society 2014 멀티미디어학회논문지 Vol.17 No.8

Software Defined Network (SDN) is a new technology in computer network area which enables user to centralize control plane. The security issue is important in computer network to protect system from attackers. SYN flooding attack is one of Distributed Denial of Service attack methods which are popular to degrade availability of targeted service on Internet. There are many methods to protect system from attackers, i.e. firewall and IDS. Even though firewall is designed to protect network system, but it cannot mitigate DDoS attack well because it is not designed to do so. To improve performance of DDOS mitigation we utilize another mechanism by using SDN technology such as OpenFlow and sFlow. The methodology of sFlow to detect attacker is by capturing and sum cumulative traffic from each agent to send to sFlow collector to analyze. When sFlow collector detect some traffics as attacker, OpenFlow controller will modify the rule in OpenFlow table to mitigate attacks by blocking attack traffic. Hence, by combining sum cumulative traffic use sFlow and blocking traffic use OpenFlow we can detect and mitigate SYN flooding attack quickly and cheaply.

Despite the donor's age, human adipose-derived stem cells enhance the maturation and development rates of porcine oocytes in a co-culture system

Nugraha Setyawan, Erif Maha,Oh, Hyun Ju,Kim, Min Jung,Kim, Geon A.,Lee, Seok Hee,Choi, Yoo Bin,Ra, Kihae,Lee, Byeong Chun Elsevier 2018 Theriogenology Vol.115 No.-

<P><B>Abstract</B></P> <P>The paracrine interactions between cumulus-oocyte complexes (COCs) and follicular somatic cells during <I>in vitro</I> maturation (IVM) were investigated. To optimize IVM conditions, many studies have applied exogenous growth factors and cell feeding/co-culture systems using various cell types to replicate the natural follicular microenvironment during IVM. A potential candidate as cell feeders is adipose-derived stem cells (ASCs) which secrete high levels of growth factors that have roles in oocyte maturation. However, the cell donor's age should be considered because biological aging also occurs in stem cells. In the present study, the contributions of ASCs from young and old donors on an IVM co-culture system were analyzed by comparing the oocyte maturation rate, cumulus expansion index, preimplantation development after parthenogenetic activation (PA), and expression of growth factor signaling genes related to oocyte maturation in ASCs, oocytes and cumulus cells under the same culture conditions. Our study demonstrated that the confluence, viability and cell size of ASCs between young and old donors were not significantly different and only the Fibroblast Growth Factor 2 (<I>FGF2</I>) signaling gene showed higher expression in ASCs from young donors. The oocyte maturation rate in the young donor group (87.8 ± 1.2%) was significantly higher than in the old donor (81.1 ± 2.1%) and control (73.8 ± 2.1%) groups. After IVM, most gene expression levels in oocytes and cumulus cells in the co-culture groups were higher than in the control but the apoptotic ratios were reduced. The blastocyst development rates were not different between the young and old donor groups (23.9 ± 1.3% and 20.7 ± 0.8%, respectively) but the percentages were higher in both groups compared to the control group (16.4 ± 1.2%). A similar pattern was also found for blastocyst total cell numbers in that the young donor group (87.5 ± 5.2 cells) was not different than the old donor group (77.5 ± 3.4 cells) but both groups exhibited higher number of cells compared with the control group (57.9 ± 6.0 cells, p < .05). Our study strongly suggested that the co-culture IVM system with ASCs greatly improved the maturation and development rates of porcine oocytes. Moreover, ASCs from young donors more effectively supported porcine oocyte maturation than those from old donors although this difference did not translate into improved developmental competence.</P> <P><B>Highlights</B></P> <P> <UL> <LI> IVM with co-culture strategy improved the effectivity of oocyte maturation. </LI> <LI> The confluence, viability and cell size between young and old donor were similar. </LI> <LI> The FGF2 signalling gene showed higher expression in young ASCs donor. </LI> <LI> Maturation rate in young donor was the highest than old donor and control groups. </LI> <LI> Co-culture IVM system up regulated most of signalling genes in oocytes and cumulus. </LI> </UL> </P>

Hybrid learning as alternative approach to improve Indonesian medical students’ attitude towards clinical skills during COVID-19 pandemic

Nugraha David,Melbiarta Rezy Ramawan,Visuddho Visuddho,Rimbun Rimbun,Sakina Sakina,Herawati Lilik,Ummah Fithriyah Cholifatul,Rejeki Purwo Sri,Romdhon Achmad Chusnu 한국의학교육학회 2023 Korean journal of medical education Vol.35 No.4

Purpose: Hybrid learning has been chosen as an alternative method in the conduction of clinical skill lectures during coronavirus disease 2019 (COVID-19) pandemic since students need to learn skills applied in emergency situations. This study aims to analyze students’ attitudes between hybrid and online learning methods.Methods: A non-randomized study was conducted between hybrid group (HG) and online group (OG) on three courses (intravenous [IV]-line insertion, nasogastric tube [NGT] insertion, and neonatal resuscitation). We developed a preformed validated questionnaire to assess students’ attitudes in five domains (willingness, understanding, capacity, self-efficacy, and intended behavior). The questionnaire was applied at the pre- and post-intervention.Results: A total of 100 participants were included (n=49 in HG, n=51 in OG). Post-course attitudes were significantly higher in online (IV-line, p=0.000; NGT, p=0.000; resuscitation, p=0.000) and hybrid (IV-line, p=0.000; NGT, p=0.000; resuscitation, p=0.000) groups compared to their pre-course. There were no significant differences in post-course attitude between groups (IV-line, p=0.072; NGT, p=0.163; resuscitation, p=0.146). Normalized-gain scores of all subjects were higher in HG (IV-line, p=0.012; NGT, p=0.085; resuscitation, p=0.033).Conclusion: In conclusion, hybrid learning could be considered as a better alternative in clinical skill lectures to maximize students’ attitudes, especially during COVID-19 pandemic.

The Impact of Community-Based Forest Management on Local People around the Forest: Case Study in Forest Management Unit Bogor, Indonesia

Nugraha Cahya Fajar,김준순 강원대학교 산림과학연구소 2019 Journal of Forest Science Vol.35 No.2

The issue of sustainable forest management (SFM) continues to emerge as part of the REDD+ mechanism mitigation efforts. Especially for some developing countries, such as Indonesia, forest management is required to provide benefits to the welfare of local communities in addition to forest conservation efforts. This study aims to identify the economic, social, and environmental impacts of community-based forest management (CBFM) implementation activities, which is one of the implementations of SFM at field level. The primary objectives were to find out the impacts of CBFM activities based on local people’s perceptions and to identify what factors need to be considered to increase local people’s satisfaction on CBFM activities. The data from 6 sub-villages was derived through surveys with local people involved in CBFM activities, interviews with a key informant, and supported by secondary data. The results of the study state that CBFM activities have increased the local people’s income as well as their welfare, strengthening the local institution, and help to resolve conflicts in the study area. CBFM has also been successful in protecting forests by rehabilitating unproductive lands and increase forest cover area. By using binary logistic regression analysis, it found that income, business development opportunities, access to forests, conflict resolution, institutional strengthening, and forest rehabilitation variable significantly affected the local people’s satisfaction of CBFM activities.

Data Imputation using Auto-Encoder for Design Specification of Glass Run Channel

Nugraha Agung,Hye-Rin Kwon,Gyeong-Ho Park,Min-Soo Kim,Ji-Hwan Lee 대한산업공학회 2022 대한산업공학회 추계학술대회논문집 Vol.2022 No.11

Verification of the Glass Run Channel process design, the automotive window seal, typically takes several days or weeks. Typically, the reason of this issue is dependent on the engineers level of experience with this technique. The requirements of a framework that is both capable of resolving the issue and simple to use will boost the work efficiency. This issue can be classified as an imputation problem in which the data itself is Missing Completely at Random (MCAR). The problem is resolved with the Auto-Encoder. The results demonstrate that the proposed Auto-Encoder has a performance that is comparable to that of our benchmark, the KNN Imputer. In contrast, the Auto-Encoder fared better than the KNN Imputer in terms of time processing.

Inspection Building: Path Planning with UAV in Dynamic Environment”

Nugraha Ramdhan,Soo Young Shin 한국통신학회 2022 한국통신학회 학술대회논문집 Vol.2022 No.6

Autonomous Navigation for Rover with Ackerman Steering using GPS

Nugraha Ramdhan,Fussy Dirgantara,Munkyu Choi,Soo Young Shin 한국통신학회 2023 한국통신학회 학술대회논문집 Vol.2023 No.2

Perception of the Forest Area and Willingness to Pay for Household Waste Management Services in Villages around the Sawala Mandapa Education and Training Forest, Majalengka, Indonesia

Gugie Nugraha 경희대학교 국제학연구원 2021 Asian Journal of International Studies (AJIS) Vol.26 No.1

Forest area with special purposes of Sawala Mandapa Education and Training Forest not only has a lot of progress in development but also challenges. The most important challenge is the misuse of the area as a waste dumpsite. The problem of accumulating waste in forest areas is caused by a lack of public awareness in managing and processing household waste. Meanwhile, support from the local government, the Environmental Service of Majalengka District, has limitations in the transportation and management of household waste. Therefore, efforts are needed in dealing with waste management in villages around forest areas to achieve public health and forest preservation. Efforts to deal with the problem of misuse of forest areas as places for accumulating waste require finding information about community perceptions of household waste management and forest area preservation. This study aims to determine community perceptions of forest areas and willingness to pay for household waste management. A survey instrument in the form of a questionnaire has been used as a basis for collecting data on the community’s perceptions and knowledge of forest areas and their willingness to pay for household waste management services. Multiple linear regression models were processed by SPSS 27 software were used to test the hypothesis.

Smart Lighting based Fuzzy Logic Controller to Reduce Energy Consumption

Ramdhan Nugraha,Daniar Estu Widiyanti,Muhammad Wicaksono,Soo Young Shin 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.6

The use of electrical energy for offices is quite burdening the company's cash flow. In addition, inadequate lighting levels will reduce the quality of our eye vision. In this work, the fuzzy logic controller is used to reduce energy consumption. The work system is used to detect human movement and light intensity. If movement is detected in a location, the surrounding lights will light up according to the desired light intensity. In the same room, not all lights are on, only in areas that detect human movement. This system is integrated with the Internet of Things so that electric power can be monitored and predicted in the future. The tests that have been carried out resulted in savings in electrical energy of 50.7 % from the previous month.

Regional Evaluation of Potential Landslide Earthquake and Wave Vibration Effect Based Relative Method (rem) and Geotechnical Mapping

Bayu Nugraha 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6