Water retention properties of the clay in soils developed on clayey sediments: significance of parent material and soil history

International audienceWe have investigated the water retention properties of clayey subsoil horizons according to the variation of clay characteristics. The horizons studied developed on a large range of age and facies of calcareous or calcium-saturated clayey sediments. The water retention properties were studied from −10 hPa to −15 000 hPa water potential using small clods collected in winter when swelling is at a maximum and water content close to field capacity. The specific water content and volume of the clods at field conditions, their specific volume at −15 000 hPa water potential, the clay content, the organic carbon content, the cation exchange capacity, the N2-BET surface area and calcareous content were measured. The clay fabric, which is the spatial distribution of the elementary clay particles, was quantified when the soil was close to field capacity and we could attribute the whole pore volume to the porosity of the clay fabric. Our results show that the water retention properties of the clay vary greatly from one soil to another with respect to the clay fabric. The variation of the latter depends on the cation exchange capacity, the size of elementary particles and hydric stress history of the clay. We show that the water retention properties of the studied clayey soils vary according to the clay content and fabric, the latter being related either to parent material fabric or to both the hydric history of the soil and size of the elementary clay particles

Pengembangan Sumber Belajar Digital Berbasis Web pada Mata Kuliah Kewirausahaan

Sumber belajar salah satu kunci keberhasilan dalam mencapai tujuan pembelajaran. Berbagai macam sumber belajar yang dapat dikembangkan misalnya portal digital berbasis web. Produk pembelajaran ini dikembangkan untuk matakuliah kewirausahaan di Jurusan Teknologi Pendidikan IKIP Mataram. Tujuan penelitian ini adalah 1) menghasilkan produk dengan spesifisikasi atau fitur-fitur pembelajaran 2) menghasilkan sumber belajar digital berbasis web yang layak digunakan dalam mata kuliah kewirausahaan 3) mengetahui efektifitas pembelajaran produk. Metode yang dipakai dalam penelitian ini adalah penelitian dan pengembangan (R&D). Teknik analisis data yang digunakan dalam penelitian ini melalui dua cara yakni kuantitatif dan kualitatif. Hasil Penelitian ini adalah 1) Fitur pembelajaran yang dihasilkan seperti materi yang bervariasi, sistem penilaian online, dan fasilitas chating. 2) portal pembelajaran yang telah memenuhi unsur kelayakan, baik pada uji alpha untuk ahli media sebesar 4,27 dan materi 4,28 serta uji beta sebesar 4,24 yang tergolong kategori “sangat baik”. 3) Selain itu juga, portal yang dikembangkan dapat dikatakan efektif untuk digunakan dalam pembelajaran sebesar 97 % dari penilaian pretest ke posttest

Usulan Strategi Untuk Meningkatkan Daya Saing Produk Mebel Rotan Single Chair Dengan Analisis Rantai Nilai (Studi Kasus : Klaster Mebel Rotan Kab. Cirebon)

Rattan furniture industry become one of the leading sector in Indonesia where the biggest rattan processing center palced in Cirebon,West Java. However, there are some constraints in rattan furniture industry in Cirebon which include the increasing of competition among global manufacturers and the government policy that allowed rattan export lead to profits in the competing countries.Therefore, we need a strategy to enhance the competitiveness of rattan products in world markets. This strategy can be obtained by analyzing the value chain. The purposes of this study are to analyze the value chain of rattan furniture products and get the appropriate competitive strategy to be implemented by each actor within value chain. The method is carried out financial analysis, SWOT analysis, Diamond Competitiveness analysis, and analysis of Critical Success Factor (CSF). Object of research are companies which are members of the Association of Indonesian Furniture (ASMINDO) Cirebon that produced single chair rattan. From the results of data processing and analysis, the strategies that can be applied in suppliers are to establish a subsidiary in the available raw materials and merged with the company. The strategies that can be applied in the company are applying its labor costs per unit of product produced, the allocation of funds for promotion, buyers prioritize subscriptions, sharing information and innovation with the buyer, has a high flexibility in terms of quality and price, collaborate with associations and government in exhibitions, and merged with another company or with suppliers. While strategies that can be applied in buyer in this case wholeseller are to lower the price of the product, maximize promotion and maintaining good relationships with companies that already truste

Penentuan Lot Pesanan Dan Periode Pemesanan Menggunakan Teknik Lotting Dan Penentuan Safety Stock Untuk Arabian Light Crude Sebagai Umpan Fuel Oil Complex 1 Pada Bulan September 2014 Di PT Pertamina (Persero) Refinery Unit IV Cilacap

PT. Pertamina (Persero) Refinery Unit IV Cilacap are under the responsibility of the Directorate processing PT. Pertamina (Persero), is one of the Public Server Obligation (PSO) to the government that one of his responsibilities is to provide fuel for various purposes in Indonesia. As a manufacturer of fuel, PT. Pertamina (Persero) RU IV Cilacap need of Crude Oil as feed or main raw materials. One of crude oil type used as a raw material in the PT. Pertamina (Persero) RU IV Cilacap is Arabian Light Crude (ALC), which is the crude oil from Saudi light crude categories. Units within the company that is using ALC as feed, one of which was crude Distilate I Unit (CDU) in the Fuel Oil Complex I. The number and the booking period ALC has been done based on orders from Pertamina Head Manager. The basis for determining the number and the booking period is unknown, so the plant manager can not resolve a problem directly if there are constraints on the supply chain ALC. The theoretical approach is needed to analyze the behavior of lot size calculation system and the booking period. From these conditions, the formulation of the research problem is how to determine a lot of orders and the booking period lotting ALC using the techniques and how to determine the optimal safety stock for ALC. The purpose of the study is to determine the order and the booking period lot ALC uses lotting techniques to get a lot of orders and the booking period is optimal, determine safety stock and assess kesesesuaian ALC ALC purchase contract with the theoretical results of data processing. Results of the research showed orders lot ALC was 1.680.000 barrels. ALC booking period is done every 15 days. ALC optimal safety stock is 552.671 barrels. ALC lot size compared with theoretical calculations give a lot suitability of 93.33% results

Functional Condition Rating Segment Sragen Ring Road South, Central Java Province

Assessment of pavement condition is functionally the most important aspect in determining road maintenance and repair activities, so that the financing can be monitored properly. There are two methods in handling the road assessment, ie visually and using tools. Visual assessment can use PASER and PCI. While IRI is a road assessment using Roadroid (Android Smartphone App) tool, where the tool will be used as national reference to get IRI value, because the cost is cheaper and effective. Therefore there needs to be a correlation between the three methods. Correlation in this research is divided into three, namely the correlation of PASER value with PCI, PASER with IRI, and PCI with IRI. The research location used as research object is South Ring Road Sragen. The result of the research was obtained, road assessment using PASER method with PCI resulted correlation value of pearson 0,51. Assessment of PASER with IRI has a correlation value of pearson -0,14. While the value of PCI with IRI yield correlation value pearson -0,23. The value of the correlation coefficient between PASER and PCI has the highest value, since it has a nearly equal assessment approach by measuring the damage visually. The correlation of PCI with IRI is higher than PASER with IRI, thus proving that PCI assessment is more recommended because it can accommodate all types of road damage