Distributed Model Reference Control for Cooperative Tracking of Vehicle Platoons Subjected to External Disturbances and Bounded Leader Input

Agung Prayitno,Itthisek Nilkhamhang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.6

This paper proposes a distributed model reference controller (DMRC) for cooperative tracking of vehicle platoons subjected to unknown external disturbances and bounded, non-zero leader input. The vehicle-to-vehicle communication network topology is assumed to be directed and contains at least one spanning tree with the leader as a root node. The proposed scheme utilizes the cooperative tracking error reference as a virtual reference for each follower. The main control system is designed using cooperative tracking error and cooperative disagreement error to attenuate the effects of unknown external disturbance and allow for bounded leader input. The global disagreement error is shown to be uniformly ultimately bounded through detailed stability analysis, such that the states of each follower synchronize to the leader states with bounded residual error, and guarantees input-to-state string stability (ISSS) of the platoon. Performance verification is conducted through simulations and validates the efficacy of DMRC for the vehicle platoon problem.

Mediating Roles of Job Satisfaction toward the Organizational Commitment of Employees in the Public Sector

INGSIH, Kusni,PRAYITNO, Agus,WALUYO, Dwi Eko,SUHANA, Suhana Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.10

This study provides an understanding of the role of job satisfaction as a mediator of compensation and workplace environments for the organizational commitment of employees in the public sector. This study used a structural model using path analysis. The population and sample in this study were all employees at the Population and Civil Registry Office of one of the districts in Indonesia. The sampling technique used was total sampling, due to the considerably smaller amount of the sample size. This study found that compensation and workplace environment could explain job satisfaction variables with a 93.8% confidence level and simultaneously compensation, workplace environment, and job satisfaction that could explain organizational commitment with a variable of 97.4%. This findings also shows that the manifest bonus variable on the latent compensation variable is one of the main indicators that needs to improve to increase job satisfaction and organizational commitment. One of the important things which needs to be done is to increase compensation. The first thing which needs to be done is to increase the bonus. Furthermore, to improve the quality of the workplace environment, facilities, and infrastructure such as stable internet connections, computer specifications are the important criteria that must be met.

The Effect of Training, Information Technology, Intellectual and Emotional Intelligence on Teacher's Performance

INGSIH, Kusni,PRAYITNO, Agus,WALUYO, Dwi Eko,SUHANA, Suhana,ALI, Shujahat Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.12

The performance of a teacher has an important role in the success of education in general. This study aims to determine the factors that affect the decline in teacher performance in one of the junior secondary schools in Indonesia. Based on the literature review, four exogenous variables were identified, namely, training, utilization of information technology, intellectual intelligence, and emotional intelligence. This study uses primary data, collected from a questionnaire distributed to respondents. The questionnaire items are measured using a Likert scale. The sample in this study were all teachers at MTS Darul Falah Sirahan, totaling 32 people. The analysis technique used in testing the hypothesis of this study is multiple regression analysis. Statistical product and service solutions are used as analysis tools. The results of this study indicate that only the variable 'utilization of information technology' has a positive and significant effect. However, the variables 'training,' 'intellectual intelligence,' and 'emotional intelligence' did not have a significant effect. This finding contradicts the literature in general. Therefore, this study recommends improving training methods, both those carried out internally by schools and by related agencies, and schools still need to optimize guidance and potential for teacher's intelligence in improving performance.

Nexus between Production Input and Price Commodity: An Integration Analysis of Rice Barns in East Java of Indonesia

WULANDARI, Dwi,NARMADITYA, Bagus Shandy,PRAYITNO, Putra Hilmi,ISHAK, Suryati,SAHID, Sheerad,QODRI, Lutfi Asnan Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.10

This study aims to examine the causality between production input and the price of rice in East Java, Indonesia. This study applied a quantitative method to understand in a comprehensive way the correlation between variables. The data used for this study were collected from several sources, including East Java Agriculture Office, Siskaperbapo.com, and Statistics Indonesia (BPS) of East Java. This research was carried out over five years, starting from 2014 to 2018. Furthermore, the data were analyzed using the Vector Error Correction Model (VECM) by employing E-Views (version 7). The findings of this study indicated that, in the long run, the population, rice production, and changes in people's income have a positive effect on price stability, but are inversely proportional if seen in the short term. In comparison, in the long run, farmer exchange rates variable has a negative impact on price stability, and inversely proportional in the short term, which has a positive effect. There are different implications when the people's income increases and the rice price declines; these have great potential to alleviate poverty in East Java, Indonesia. This is due to the fact that the price stability also concerns the welfare of the community.

Properties of a New Adhesive Composed of Gambir-Sucrose

( Tito Sucipto ),( Ragil Widyorini ),( Tibertius Agus Prayitno ),( Ganis Lukmandaru ) 한국목재공학회 2020 목재공학 Vol.48 No.3

Gambir is a non-wood forest product with a potential of being used as wood adhesive, due to about 33% catechin in it. Meanwhile, catechins and sucrose have not been studied as adhesives. Therefore, basic characteristics of gambir-sucrose adhesives were investigated. In this research, adhesives were prepared by dissolving gambir and sucrose in distilled water, at different blending ratios of the gambir/sucrose such as 100/0, 75/25, 50/50, and 25/75 wt%. Furthermore, gas chromatography-mass spectrometry (GC-MS) was employed to determine the gambir chemical compositions, and Fourier transform-infrared (FTIR) spectroscopy was carried out to identify chemical bonds. Particleboards with a target density of 0.8 g/cm3 were then manufactured by hot-pressing for 10 min at 200℃. The internal bond (IB) strength of particleboard was subsequently measured. Based on the GC-MS analysis, 31.11% of catechin was identified. In addition, the viscosity, density, solid content, and gelation time of the adhesives, and insoluble matter content (IMC) in boiling water were 7.30~33.24 mPa.s, 1.2~1.3 g/cm3, 25.56~28.44%, 73~420 min, and 29.75~62.10%, respectively. Adding sucrose to the adhesive was observed to raise the IMC from 49.05 to 62.10%, at 180℃ and 200℃. FT-IR analysis showed that the gambir absorption peaks occurred at approximately 1620 cm-1, assigned to the C=O stretching of 5-hydroxymethylfurfural, which tended to increase with the addition of sucrose. The reaction between gambir and sucrose was observed in the form of the dimethylene ether bridge. The 25/75 wt% gambir-sucrose adhesives and 200℃ hot-pressed temperature resulted in the highest IB strength (0.89 MPa), and met the requirement of JIS A5908-2003 type 18. Consequently, the gambir-sucrose adhesive could be used as a particleboard adhesive.

말레이시아 13대 총선: 사바주(Sabah)는 국민전선의 텃밭인가?

자이니오스만 ( Zaini Othman ),에코프레이트노조코 ( Eko Prayitno Joko ),람리돌라 ( Ramli Dollah ),암룰라마레인닝 ( Amrullah Maraining ),김종업 ( Kim Jong Eop ) 한국동남아학회 2016 동남아시아연구 Vol.26 No.3

말레이시아 사바주(Sabah)의 12대(2008)와 13대(2013) 총선의 결과는 독립 이후 말레이시아에서 여당 연합을 형성해 온 국민전선 (Barisan Nasional: BN)은 서서히 사바주의 정치에서 지배력이 이전과 다름을 보여주는 의미있는 결과를 보여준다. 12대 총선 이후 사바주는 국민전선의 정치적 텃밭에서 서서히 정치적 영향력(특히 주의 회 선거)이 약해됨을 보여준다. 비록 13대 총선에서 국민전선(BN)이 겉으로는 사바주의 연방의회 의원 의석을 가져가는 등 정치적 텃밭으로 보여주지만, 이전에 비해 득표력이 떨어졌음을 알 수 있다. 본 연구는 사바주의 13대 총선 결과는 사바주를 여당 연합인 국민전선(BN)의 텃밭(fixed-deposit state)로 부를 수 있는지를 말레이 총선 결과를 토대로 살펴보았다. 이를 위해 본 연구는 문헌 연구를 중심으로 하여 말레이시아의 12대와 13대 총선 결과를 토대로 하여 이전의 총선의 결과와 비교하여 정치적인 변화와 함께 사바주의 사회문화 적·종교적 환경을 바탕으로 한 변화의 조짐을 분석하였다. As all are aware, the results of the Malaysia 12th General Election (GE-12) in 2008 have surprised many. Not only the dominant parties Barisan Nasional (BN) were shocked by the loss of significant numbers of seats but for the first time in the history of Malaysia politics, vis-a-vis, electoral affairs, they were denied a two-thirds majority in the Parliament. Notwithstanding the opposition parties such as Parti Islam Se-Malaysia (PAS), Democratic Action Party (DAP) and Parti Keadilan Rakyat (PKR: The People`s Justice Party) that form the opposition coalition called Pakatan Rakyat (People`s Alliance: PR), has come to a surprised with the GE-12 result, in which they not even think that were able to challenge hegemonic politics of BN, managed to capture and formed a government at the state level namely Kedah, Penang, Perak, and Selangor, except Kelantan which has been under the control of PAS since the 1990 general election. This article aims to analyze whether Sabah as a “fixed deposit”state is still relevant in understanding the continuity and survival of the BN political hegemony in the context of Malaysia political developments post-13th general election.

Dynamic Modulus of Three-Layer Boards with Different Furnish and Shelling Ratio

Muhammad Navis Rofii,Tibertius Agus Prayitno,Shigehiko Suzuki 한국목재공학회 2016 목재공학 Vol.44 No.2

This aims of this study were to investigate the relationship between non-destructive evaluation (NDE) and actual bending properties of particleboard, and to predict the bending properties of three-layer particleboard. Three kinds of raw materials, i.e. Hinoki (Chamaecyparis obtusa Endl.) strand, knife-milled Douglas-fir (Pseudotsuga manziesii (Mirb) Franco), and hammer-milled matoa (Pometia spp.) obtained from wooden industry, were utilized as furnish for experimental panel with methylene diphenyl diisocyanate (MDI) resin as binder. The NDE test was conducted by hit sounds using an FFT analyzer according to the spectrum peak of wave frequency, while the static bending test was conducted according to JIS A-5908. The results reveal that the dynamic Young’s modulus as an NDE test has a potential for being used to predict the elastic bending of particleboards by a specific equation for adjusting its proper values. The values of NDE and static test are significantly different with a deviation range at 3-20%. The bending stiffness of three-layer particleboards manufactured from different wood species is predictable by observing the bending stiffness of two elements based on the thickness of its layers. The predicted values of bending stiffness and static test are significantly different with a deviation range at 5-24%.

Bonding Performance of Maltodextrin and Citric Acid for Particleboard Made From Nipa Fronds¹

Mahdi Santoso,Ragil Widyorini,Tibertius Agus Prayitno,Joko Sulistyo 한국목재공학회 2017 목재공학 Vol.45 No.4

Maltodextrin and citric acid are two types of natural materials with the potential as an eco-friendly binder. Maltodextrin is a natural substance rich in hydroxyl groups and can form hydrogen bonds with lignoselulosic material, while citric acid is a polycarboxylic acid which can form an ester bond with a hydroxyl group at lignoselulosic material. The combination of maltodextrin and citric acid as a natural binder materials supposed to be increase the ester bonds formed within the particleboard. This research determined to investigate the bond-ing properties of a new adhesive composed of maltodextrin/citric acid for nipa frond particleboard. Maltodextrin and citric acid were dissolved in distillated water at the ratios of 100/0, 87.5/12.5, 75/25 and 0/100, and the concentration of the solution was adjusted to 50% for maltodextrin and 60% citric acid (wt%). This adhesive solution was sprayed onto the particles at 20% resin content based on the weight of oven dried particles. Particleboards with a size of 25 × 25 × 1 cm, a target density 800 kg/m³ were prepared by hot-pressing at press temperatures of 180℃ or 200℃, a press time of 10 minute and board pressure 3.6 MPa. Physical and mechanical properties of particleboard were tested by a standard method (JIS A 5908). The results showed that added citric acid level in maltodextrin/citric acid composition and hot-pressing temperature had affected to the properties of particleboard. The optimum properties of the board were achieved at a pressing temperature of 180℃ and the addition of only 20% citric acid. The results also indicated that the peak intensity of C=O group increased and OH group decreased with the addition of citric acid and an increase in the pressing temperature, suggesting an interreaction between the hydroxyl groups from the lignocellulosic materials and carboxyl groups from citric acid to form the ester groups.

The Gastroesophageal Reflux Disease Questionnaire in Adolescents: What Is the Best Cutoff Score?

Dian Artanti,Badriul Hegar,Nastiti Kaswandani,Soedjatmiko,Ari Prayitno,Yoga Devaera,Yvan Vandenplas 대한소아소화기영양학회 2019 Pediatric gastroenterology, hepatology & nutrition Vol.22 No.4

Background: A self-assessment questionnaire, the GERD-Questionnaire (GERD-Q) was used to determine the prevalence of GERD in adolescents, describe the related factors, and determine the impact on quality of life (QoL). Methods: The incidence of GERD was evaluated using the GERD-Q in adolescents aged 12–18 years. The Pediatric Gastroesophageal Reflux Disease Symptom Questionnaire and Quality of Life Questionnaire (PGSQ-A) for adolescents were additionally administered. Some factors considered related to GERD were also evaluated. Results: The 520 adolescents were included. The prevalence of suspected GERD, according to a GERD-Q cutoff score of ≥7 was 32.9%, and those drinking soda were 1.7 times more likely to have GERD (95% confidence interval, 1.3–2.2; p <0.001). However, soda consumption was not a risk factor for development of GERD symptoms. Applying a cutoff score of ≥8, only 10.9% of the participants had a positive GERD score, but the association with soda consumption persisted. The median PGSQ-A score in subjects suspected of GERD was 8 (range 0–37) on weekends and 1 (range 0–17) during weekdays ( p <0.001) compared to those not suspected of GERD, with a median of 2 (range 0–27) during weekends and 0 (range 0–10) during weekdays. Heartburn, regurgitation, and extraesophageal symptoms correlated significantly with QoL ( p <0.001). Conclusion: The prevalence of suspected GERD in adolescents was 32.9% or 10.9%, depending on the cutoff score used. There was a statistically significant difference in PGSQ-A scores between the subjects suspected or not of GERD, indicating an impaired QoL.

Properties of Citric Acid-bonded Composite Board from Elephant Dung Fibers

( Ragil Widyorini ),( Greitta Kusuma Dewi ),( Widyanto Dwi Nugroho ),( Tibertius Agus Prayitno ),( Agus Sudibyo Jati ),( Muhammad Nanang Tejolaksono ) 한국목재공학회 2018 목재공학 Vol.46 No.2

An elephant digests only around 30~45% of what it consumes; therefore the undigested material mainly passes as intact fibres. Elephant food is usually composed of grass, leaves, twigs, bark, fruit and seed pods. This research aimed to utilize the elephant dung fibers as material for composite board and citric acid as a bonding agent. Citric acid contents in this research were set at 0 wt% (binderless composite board), 10 wt%, 20 wt%, and 30 wt% based on dry weight particles, while the target density was set at 0.8 g/cm³. Pressing temperatures were set at 180℃ and 200℃ with the pressing time was 10 minutes. Physical and mechanical properties tests were then performed according to Japanese Industrial Standard A 5905. The result showed that elephant dung fibers could be used as potential materials for composite board. Addition of citric acid and pressing temperature significantly increased the quality of composite board. Infrared analysis indicated that the presence of ester linkages much higher with the increasing of citric acid content and pressing temperature. The optimum properties of composite board made from elephant dung fibers could be achieved at pressing temperature of 200℃ and a citric acid content of 20 wt%.