A Study of Two Successful Language Learners: Insights on WTC & Learning Strategies

( Lama Nassif ) 서강대학교 언어정보연구소 2010 언어와 정보 사회 Vol.13 No.-

Lama Nassif(2010), “A Study of Two Successful Language Learners:Insights on WTC & Learning Strategies”, Language & Information Society 13, A close analysis of language learners` insights on their own learning have been shown to provide useful information on the route their learning takes and offer insights into the language learning as a whole. This study focused on two successful language learners, exploring the paths their learning experiences took via three methods of data collection:interviews, a questionnaire, and the Strategy Inventory for Language Learning. The results revealed that the learners` willingness to communicate and language learning strategies were of particular significance in their learning experiences, positively impacting their language development and competency. The participants also had characteristics that have been associated with successful language learners in previous research. Excerpts from the learners` data are presented and analyzed. Finally, some pedagogical recommendations are presented.

1P-389 Metabolic engineering of Klebsiella pneumonias for the production of 1,3-propanediol from glucose

( Lama Suman ),박성훈 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.0

Internal modifications to reduce pollutant emissions from marine engines. A numerical approach

Lamas, M.I.,Rodriguez, C.G.,Rodriguez, J.D.,Telmo, J. The Society of Naval Architects of Korea 2013 International Journal of Naval Architecture and Oc Vol.5 No.4

Taking into account the increasingly stringent legislation on emissions from marine engines, this work aims to analyze several internal engine modifications to reduce $NO_x$ (nitrogen oxides) and other pollutants. To this end, a numerical model was employed to simulate the operation cycle and characterize the exhaust gas composition. After a preliminary validation process was carried out using experimental data from a four-stroke, medium-speed marine engine, the numerical model was employed to study the influence of several internal modifications, such as water addition from 0 to 100% water to fuel ratios, exhaust gas recirculation from 0 to 100% EGR rates, modification of the overlap timing from 60 to $120^{\circ}$, modification of the intake valve closing from 510 to $570^{\circ}$, and modification of the cooling water temperature from 70 to $90^{\circ}C$. $NO_x$ was reduced by nearly 100%. As expected, it was found that, by lowering the combustion temperature, there is a notable reduction in $NO_x$, but an increase in CO (carbon monoxide), HC (hydrocarbons) and consumption.

An Efficient Architecture Design of Low Complexity in Quantization of H.264/AVC

Lama, Ramesh Kumar,Yun, Jung-Hyun,Kwon, Goo-Rak Korea Multimedia Society 2011 멀티미디어학회논문지 Vol.14 No.10

An efficient architecture for the reduction of complexity in forward quantization of H.264/AVC is presented in this paper. Since the multiplication operation in forward quantization plays crucial role in complexity of algorithm. More efficient quantization architecture with simplified high speed multiplier is proposed. It uses the modification of the quantization operation and the high speed multiplier is applied for simplification of quantization process.

Metabolic engineering of <i>Klebsiella pneumoniae</i> J2B for the production of 1,3-propanediol from glucose

Lama, Suman,Seol, Eunhee,Park, Sunghoon Elsevier Applied Science 2017 Bioresource technology Vol.245 No.2

<P><B>Abstract</B></P> <P>The production of 1,3-propanediol (1,3-PDO) from glucose was investigated using <I>Klebsiella pneumoniae</I> J2B, which converts glycerol to 1,3-PDO and synthesize an essential coenzyme B<SUB>12</SUB>. In order to connect the glycolytic pathway with the pathway of 1,3-PDO synthesis from glycerol, i.e., to directly produce diol from glucose, glycerol-3-phosphate dehydrogenase and glycerol-3-phosphate phosphatase from <I>Saccharomyces cerevisiae</I> were overexpressed. Additionally, the effect of expression levels and the use of isoforms of these two enzymes on glycerol and 1,3-PDO production were studied. Furthermore, to prevent loss of produced glycerol, the glycerol oxidation pathways were disrupted. Finally, the conversion rate of glycerol to 1,3-PDO was increased via homologous overexpression of glycerol dehydratase and 1,3-PDO oxidoreductase. The resultant strain successfully produced 1,3-PDO from glucose at a yield of 0.27mol/mol along with glycerol at 0.52mol/mol. Improvement of the engineered <I>K. pneumoniae</I> J2B to further increase conversion of glycerol to 1,3-PDO is discussed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>K. pneumoniae</I> J2B feasibility for 1,3-PDO production from glucose was studied. </LI> <LI> <I>K. pneumoniae</I> J2B was engineered and overexpressed GPD, GPP, GDHt and DhaT. </LI> <LI> The recombinant strain produced 1,3-PDO from glucose, but with low yield. </LI> <LI> CCR, byproducts accumulation and NADH unavailability reduced 1,3-PDO production. </LI> </UL> </P>

2P-324 Metabolic engineering of Klebsiella pneumoniae for the production of 1,3-propanediol from glucose

( Lama Suman ),박성훈 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

1,3-propanediol (1,3-PDO) is an industrially important chemical with increasing demand as an intermediate to fibers and resins. No natural microorganism can produce 1,3-PDO directly from glucose and only few scientific details on glucose-based 1,3-PDO production were disclosed. This study aims to provide information on glucose-based 1,3-PDO production using Klebsiella pneumoniae J2B as a microbial cell factory which can convert glycerol to 1,3-PDO and synthesize an essential coenzyme B12. K. pneumoniae J2B was engineered to have synthetic pathway which connect glycolytic pathway with that of 1,3-PDO synthesis from glycerol, thus to directly produce the diol from glucose. In addition, glycerol dissimilation pathways were disrupted. Furthermore, the metabolic flux toward 1,3-PDO was improved by modulation of byproduct formation pathway and fulfilling the demand of NADH. The engineered strains successfully produce 1,3-PDO from glucose.

Network Forensics and Intrusion Detection in MQTT-Based Smart Homes

Lama AlNabulsi,Sireen AlGhamdi,Ghala AlMuhawis,Ghada AlSaif,Fouz AlKhaldi,Maryam AlDossary,Hussian AlAttas,Abdullah AlMuhaideb International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.4

The emergence of Internet of Things (IoT) into our daily lives has grown rapidly. It's been integrated to our homes, cars, and cities, increasing the intelligence of devices involved in communications. Enormous amount of data is exchanged over smart devices through the internet, which raises security concerns in regards of privacy evasion. This paper is focused on the forensics and intrusion detection on one of the most common protocols in IoT environments, especially smart home environments, which is the Message Queuing Telemetry Transport (MQTT) protocol. The paper covers general IoT infrastructure, MQTT protocol and attacks conducted on it, and multiple network forensics frameworks in smart homes. Furthermore, a machine learning model is developed and tested to detect several types of attacks in an IoT network. A forensics tool (MQTTracker) is proposed to contribute to the investigation of MQTT protocol in order to provide a safer technological future in the warmth of people's homes. The MQTT-IOT-IDS2020 dataset is used to train the machine learning model. In addition, different attack detection algorithms are compared to ensure the suitable algorithm is chosen to perform accurate classification of attacks within MQTT traffic.

Performance Evaluation of SDN Controllers: RYU and POX for WBAN-based Healthcare Applications

Lama Alfaify,Nujud Alnajem,Haya Alanzi,Rawan Almutiri,Areej Alotaibi,Nourah Alhazri,Awatif Alqahtani International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.7

Wireless Body Area Networks (WBANs) have made it easier for healthcare workers and patients to monitor patients' status continuously in real time. WBANs have complex and diverse network structures; thus, management and control can be challenging. Therefore, considering emerging Software-defined networks (SDN) with WBANs is a promising technology since SDN implements a new network management and design approach. The SDN concept is used in this study to create more adaptable and dynamic network architectures for WBANs. The study focuses on comparing the performance of two SDN controllers, POX and Ryu, using Mininet, an open-source simulation tool, to construct network topologies. The performance of the controllers is evaluated based on bandwidth, throughput, and round-trip time metrics for networks using an OpenFlow switch with sixteen nodes and a controller for each topology. The study finds that the choice of network controller can significantly impact network performance and suggests that monitoring network performance indicators is crucial for optimizing network performance. The project provides valuable insights into the performance of SDN-based WBANs using POX and Ryu controllers and highlights the importance of selecting the appropriate network controller for a given network architecture.

Analysis of Rreviews and Usability Studies of Online Shopping Consumers

LAMA NIRAJ,SHRESTHA RAJIV,BIBEK RAI,SAPANA SHAHI,ADHIKARI MADAN 서비스마케팅학회 2022 서비스마케팅학회 학술대회 발표논문집 Vol.2022 No.11

With the popularization of online shopping, consumers have more choices to make purchasing decisions due to the diversity of brands, but due to the nature of online shopping, consumers can not directly check products and face uncertainty about the quality of many products.,Therefore, online reviews are more important for consumers to indirectly evaluate various aspects such as price and quality of products. Consumers can reduce information asymmetry and make purchasing decisions through online reviews, and reviews are more reliable than anonymous consumers' direct reviews, compared to seller information that is considered to have intent. More than 90% of reviews have been found to influence consumer purchasing decisions. In this situation, e-commerce companies offer incentives such as giveaways and discounts to high-ranking reviewers in order to obtain more customer reviews; that is because the more product reviews, the higher the customer's interest in the product. This study provides practical implications for the analysis of reviews that have not been used mainly due to the limitations of various product lines based on the generalized topic framework.,In addition, when the individual consumer's review usefulness voting pattern is reflected, more significant reviews can be placed at the top to induce the purchase of the product, and thus can be applied to the online consumer's personalization recommendation system in electronic commerce.

Multiple Description Coding Using Directional Discrete Cosine Transform

Lama, Ramesh Kumar,Kwon, Goo-Rak The Korea Institute of Information and Commucation 2013 Journal of information and communication convergen Vol.11 No.4

Delivery of high quality video over a wide area network with large number of users poses great challenges for the video communication system. To ensure video quality, multiple descriptions have recently attracted various attention as a way of encoding and visual information delivery over wireless network. We propose a new efficient multiple description coding (MDC) technique. Quincunx lattice sub-sampling is used for generating multiple descriptions of an image. In this paper, we propose the application of a directional discrete cosine transform (DCT) to a sub-sampled quincunx lattice to create an MDC representation. On the decoder side, the image is decoded from the received side information. If all the descriptions arrive successfully, the image is reconstructed by combining the descriptions. However, if only one side description is received, decoding is executed using an interpolation process. The experimental results show that such the directional DCT can achieve a better coding gain as well as energy packing efficiency than the conventional DCT with re-alignment.