Feature-Based Diversity Optimization for Problem Instance Classification

Understanding the behaviour of heuristic search methods is a challenge. This even holds for simple local search methods such as 2-OPT for the Traveling Salesperson problem. In this paper, we present a general framework that is able to construct a diverse set of instances that are hard or easy for a given search heuristic. Such a diverse set is obtained by using an evolutionary algorithm for constructing hard or easy instances that are diverse with respect to different features of the underlying problem. Examining the constructed instance sets, we show that many combinations of two or three features give a good classification of the TSP instances in terms of whether they are hard to be solved by 2-OPT.Comment: 20 pages, 18 figure

Optimizing Political Capacity of the Pro-Democracy Actors Through the Welfare Political Bloc

The paper explores problems and options that are challenged by the actors of pro-democracy movements in Indonesia. Its aim is to seek a-well-and-measurable strategies that enable the actors to continue promoting and advancing the democracy condition. The main analytical tool used in the study is the political capacity.It is assumed that the development of democracy depends on how the actors actualize their political capacity in dealing with the obstacles and opting for possible alternatives. The study concludes that during the period of 2008–2013, the Indonesian pro-democracy actors have tendency to become populist. However, there arethree groups of actor practicing populism in three different ways. The first and majority group is the actors who tend to work individually from and within parties or progressive politicians, using the charisma and popular claims, yet they are not part of the mass. The second smaller group consists of actors who associate themselves as part and work along with mass organizations, e.g. trade unions, and demand for their interests. The third is a minority group of actors who opt for building network with other equal actors and coordinating organizational based activities. This study will help the actors to optimize their capacity by creating different roles in their efforts to develop the bloc and deliver louder public voices, e.g. demanding welfare state. Such situation enables the actors to foster a common platform for the democracy movement. Keywords: Democracy, Democratization, Indonesia, Political capacity, Populis

Examination of the Colorful Semantic Approach via Telepractice for Children who are Deaf or Hard of Hearing

Introduction: Hearing loss, deafness or hard of hearing are considered to be the inabilityof perceiving sounds beyond 20 dB. Due to a direct impact of a hearing loss, a developing brain undergoes difficulties in acquiring age-appropriate syntax and speech sounds. As a result, children with hearing loss present language, speech, and literacy disabilities. The current study discusses the efficacy of the colorful semantics approach in order to see its impact on sentence structure development. Methodology: A single subject withdrawal experimental study conducted following ABAB model. Two participants (6 years and 10 years) were recruited to the study following an inclusion and exclusion criteria. The participants were administered colorful semantic therapy sessions for 12 weeks via zoom. The virtual sessions were 45 to 60 minutes long and were administered two times per week. The pre and post language skills and conversational skills were compared using cottage acquisition scales for language, listening and speech (CASLLS) and systematic analysis of language transcripts (SALT). Results: Both participants showed statistically significant improvements at the end of the intervention period. Drastic improvements were observed in four main sentence structures along with improvements in prepositions and pronouns,tenses and negations, verbs and modals and nouns and noun modifiers. The overall clarity of speech in conversations was identified according to the decline in number of mazes ( participant 1- pre intervention 11 and post intervention 7, Participant 2- pre intervention 4 and post intervention 3), number of maze words ( participant 1- pre intervention 32 and post intervention 7, Participant 2- pre intervention 5 and post intervention 3). Both participants were able to generalize conversational skills such as clarify information by repeating, using descriptions to clarifying information, using long detailed conversations and using primitive narratives in to many different contexts. The improvements in the mentioned language areas imply the effectiveness of the approach even within the virtual mode of delivery. More investigations should be done with a larger participant group to generalize the findings

BUFFER STOCK MODEL FOR STABILIZING PRICE WITH CONSIDERING THE EXPECTATION STAKEHOLDERS IN THE STAPLE-FOOD DISTRIBUTION SYSTEM

The extremely different supplies between the harvest season and the planting season are one of serious problem in the staple-food distribution system. In free-market mechanism, this extreme difference will trigger price-volatility and shortage of staple-food. This situation causes opportunity-losses for the stakeholders (producer, consumer, agent and government) in the staple-food distribution system. The government has got incurred losses because the government cannot achieve food-security for the households. The government has several price stabilization policies; one of them is market intervention policy by using buffer stock schemes to stabilize price and to reduce losses for the stakeholders. The objective of this research is to determine the buffer stock schemes required for market-intervention program. In the previous researches, the buffer stock models have been developed separately based on optimization and econometrics methods. Optimizations methods have been used to determine the level of availability with schemes consist of time and quantity of buffer stock. Econometrics methods have been used to determine the equilibrium price by using the selling-price and the amount of buffer stock. In this research, the integration of optimization model (multi-objectives programming) and econometrics model are used to develop a buffer stock model with the decision variables that consist of quantity, time, and price. Key Words: Buffer Stock Model, Market-Intervention, Price-Stabilizatio

A Buffer Stocks Model for Stabilizing Price of Commodity under Limited Time of Supply and Continuous Consumption

Staple foods, in developing countries especially in Indonesia, have extremely volatile among harvest and planting season caused by inelastic of supply-demand and price disparity. When a staple food is shortage in market, it will trigger crisis of economics, political and social because it concerns with food security. This paper develops a buffer stock model for stabilizing price of commodity under limited time of supply and continuous consumption. The performance criterion of model will consider financial loss of producer, consumer and government side when market is interfered by price-stabilization program and price-support program simultaneously. The price fluctuation will be stabilized by market operation where buffer stocks are bought from domestic and import supply point. This paper provides a price band policy that attempts to bound domestic price variation between a set of upper and lower bounds on the level of domestic prices. We consider three sets of problems reflecting different three prices elasticity from 4 period of supply and demand. Numerical examples are found to be consistent with empirical estimates regarding the relationship price elasticity with price band and with government budget for the agenda of assisting household to assure availability a staple food with enough amounts at rational prices. Keywords: buffer stocks, price band, stabilization, limited time of supply, staple foods

A Buffer Stocks Model for Stabilizing Price in Duopoly-Like Market

This paper presents the staple-food distribution problem in agro-industry. There is a great difference of staple-food supplies in the harvest-season and in the planting-season meanwhile the demand is relatively constant. This situation will trigger price-volatility and shortage of staple-food, and it causes opportunity-losses for the stakeholders (producer, consumer, wholesaler/trader, and the government). For stabilizing the price, the government has several stabilization policies; one of them is market-intervention policy by using buffer-stocks schemes. The market-intervention policy should be utilized for improving producer’s profit, for cutting consumer’s expenditure, and for sustaining wholesaler’s margin-profit by implementing price-support and price-stabilization. In duopoly-like market, we assume that there are only two market-players in the distribution system. The objective of this research is to determine the instruments for operating Market-Intervention Program which consist of the quantity, time, and price of the buffer-stocks schemes. The problem was solved using 3 approaches. First, a comparative cost/benefit analysis between free-market and intervention-market can be used to formulate the objective function of each stakeholders. Second, the integration of optimization model and econometrics model were use to develop the decision-variables subject to the expectation of stakeholders, the buffer-stocks requirement, and the dynamics price equilibrium properties. Third, model market with Inventory was applied for solving the market-price equilibrium. The result could be used to analyze such the staple-food distribution system, incorporating the configuration of duo-producers, duo market-buyers, and duo-consumers. Keywords: buffer-stocks, duopoly-like market, market-intervention program, model market with inventory, and staple-food distribution system

UNRESTRAINED MEASUREMENT OF ARM MOTION BASED ON A WEARABLE WIRELESS SENSOR NETWORK

Techniques that could precisely monitor human motion are useful in applications such as rehabilitation, virtual reality, sports science, and surveillance. Most of the existing systems require wiring that restrains the natural movement. To overcome this limitation, a wearable wireless sensor network using accelerometers has been developed in this paper to determine the arm motion in the sagittal plane. The system provides unrestrained movements and improves its usability. The lightweight and compact size of the developed sensor node makes its attachment to the limb easy. Experimental results have shown that the system has good accuracy and response rate when compared with a goniometer

Towards the Development of High-Fidelity Models for Large Scale Solar Energy Generating Systems

Small and large scale solar photovoltaic energy generating systems have been observed to take a leading place in power systems around the world which are aiming to move away from the use of fossil fuels. Technical and other challenges associated with such systems have become the focus areas of discussion and investigation in recent years. Among a range of technical challenges, power quality issues associated with the power electronic converters, especially the harmonics, are an important aspect in order to ensure that their stipulated limits are maintained. While harmonics caused by small-scale inverters, for example, those used in rooftop systems, are managed through their harmonic current emission compliance requirements, the harmonics caused by large scale inverters used in solar farms need to be managed at network levels which is essentially the responsibility of the network owners and operators. To be successful in this management process, the relevant generator connection requirements and system standards, relevant data provided by inverter manufacturers, pre-connection and post-connection studies and procedures require attention. With regard to limits associated with harmonic voltage levels at medium, high and extra high voltage (MV, HV and EHV) levels, well-established international standards exist, whereas the pre-connection study procedures which have existed for many years are now being challenged, noting the increase in the number and capacity of inverter based resources (IBRs). With regard to pre-connection harmonic compliance studies associated with power electronic based grid integrated resources or devices, the most well-known approach is the use of equivalent frequency domain models of the systems on either side of the point of connection or the grid interface. The grid is often represented by an equivalent harmonic impedance together with a corresponding background harmonic voltage. The power electronic based resources or the devices are represented by Thevenin or Norton models at the harmonic frequencies of interest, which are provided by their vendors where the approaches or the conditions under which these models are determined are not comprehensively known. It is however understood that the parameters of such equivalent circuits are mostly determined based on site tests and represent worst case harmonic performance, which do not necessarily correspond to rated power output. There is also the anecdotal understanding that such models are determined based on mathematical or simulation modelling. The most significant concern associated with such frequency domain models is their suitability for representation of the actual harmonic behaviour at a given point in time, thus posing the question of their fidelity which forms the backbone of the work presented in this thesis

Screening of in Vitro Antioxidant Activity of Seaweed, Hypnea musciformis

Seaweeds are considered as a rich source of bioactive compounds as they are able to produce a great variety of secondary metabolites characterised by a broad spectrum of biological activities including antioxidant property. However, in contrast to terrestrial plants, only a few studies have reported the antioxidant activity of seaweeds. In the present study antioxidant activities of three different solvent extracts (hexane, methanol and aqueous) of Hypnea musciformis were evaluated using DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging assay and phosphor molybdenum reduction assay. Total Phenolic Content (TPC) was evaluated using Folin-Ciocalteu method and the total flavonoid content was determined by the aluminium chloride (AlCl3) colourimetric method. Characterisation of the crude extracts were carried out using FT-IR analysis. The highest total antioxidant activity was recorded in methanol extract (14.50±0.58 AAE/g) whereas the lowest antioxidant activity was recorded in aqueous extract (0.75±0.29). The total antioxidant activity of hexane extract was recorded as 3.20±0.231 AAE/g. Butylated hydroxytoluene (BHT) was used as positive control and total antioxidant activity was recorded as 19.50±0.58 AAE/g. The highest DPPH antioxidant activity was obtained for methanol extract (IC50=28.00±2.31 mg/L) while the lowest activity was obtained for the aqueous extract (IC50=6006.00±6.93 mg/L). Gallic acid was used as the standard and BHT was used as the positive control and IC50 values were recorded as 3.50±0.38 mg/L and 24.00±1.15 mg/L respectively. The highest TPC was exhibited in methanol extract (14.02±0.03 GAE/g) whereas the lowest was recorded in aqueous extract 0.89±0.07 GAE/g. TPC of BHT was recorded as 254.93±4.43 GAE/g. The highest TFC was recorded in methanol extract (0.0170±0.04 QE/g) and the lowest TFC was recorded in aqueous extract (0.0098±0.14 QE/g). The TFC content of the hexane extract was 0.0102±0.13 QE/g. FT-IR analysis revealed the presence of alcohols/phenols, alkanes, carboxylic acids, alkenes, aromatics and aromatic amines, aliphatic amines in methanol crude extract. The study emphasises the importance of isolating and examining individual bioactive compounds present in H. musciformis for future research as it has revealed the antioxidant activities.Keywords: Hypnea musciformis, Antioxidant activity, DPP

Identifikasi Potensi Bahaya dengan Metode IBPR pada Pekerjaan Maintenance HMC

Pekerjaan maintenance alat bongkat muat petikemas dilakukan di berbagai Pelabuhan untuk memberikan perbaikan dan perawatan alat bongkar muat petikemas agar kegiatan operasional dapat berjalan dengan lancar. Pada pekerjaan ini terdapat berbagai macam potensi bahaya yang dapat menyebabkan terjadinya kecelakaan kerja yaitu bahaya physical, bahaya chemical hingga bahaya psikososial. Tujuan dari penelitian ini adalah untuk mengidentifikasi potensi bahaya, melakukan penilaian risiko, dan mengetahui pengendalian risiko pada pekerjaan maintenance HMC (Harbour Mobile Crane). Dalam identifikasi bahaya dan penilaian risiko pada penelitian ini menggunakan metode IBPR dan pengendalian risiko menggunakan hirarki pengendalian. Dari hasil identifikasi bahaya dan penilaian risiko terhadap 20 proses pekerjaan didapatkan hasil  yaitu 7 proses pekerjaan memiliki kategori risk acceptable, 10 proses pekerjaan memiliki kategori review at appropriate, dan 3 proses pekerjaan memiliki kategori high priority. Rekomendasi dilakukan pada semua potensi bahaya yang dimulai dari eliminasi, substitusi, rekayasa teknik, administrasi, dan APD. &nbsp