This study develops a model to determine the input rate of the chemical for coagulation and flocculation process (i.e. coagulant) at industrial water treatment plant, based on real-world data. To detect outliers among the collected data, a two-phase algorithm with standardization transformation and Density-Based Spatial Clustering of Applications with Noise (DBSCAN) is applied. In addition, both of the missing data and outliers are revised with linear interpolation. To determine the coagulant rate, various kinds of machine learning models are tested as well as linear regression. Among them, the random forest model with min-max scaled data provides the best performance, whose MSE, MAPE, R2 and CVRMSE are 1.136, 0.111, 0.912, and 18.704, respectively. This study demonstrates the practical applicability of machine learning based chemical input decision model, which can lead to a smart management and response systems for clean and safe water treatment plant.

This paper introduces a container loading problem and proposes a theoretical approach that efficiently solves it. The problem is to determine a proper weight of products loaded on a container that is delivered by third party logistics (3PL) providers. When the company pre-loads products into a container, typically one or two days in advance of its delivery date, various truck weights of 3PL providers and unpredictability of the randomness make it difficult for the company to meet the total weight regulation. Such a randomness is mainly due to physical difference of trucks, fuel level, and personalized equipment/belongings, etc. This paper provides a theoretical methodology that uses historical shipping data to deal with the randomness. The problem is formulated as a stochastic optimization where the truck randomness is reflected by a theoretical distribution. The data analytics solution of the problem is derived, which can be easily applied in practice. Experiments using practical data reveal that the suggested approach results in a significant cost reduction, compared to a simple average heuristic method. This study provides new aspects of the container loading problem and the efficient solving approach, which can be widely applied in diverse industries using 3PL providers.

Many manufacturers applying third party logistics (3PLs) have some challenges to increase their logistics efficiency. This study introduces an effort to estimate the weight of the delivery trucks provided by 3PL providers, which allows the manufacturer to package and load products in trailers in advance to reduce delivery time. The accuracy of the weigh estimation is more important due to the total weight regulation. This study uses not only the data from the company but also many general prediction variables such as weather, oil prices and population of destinations. In addition, operational statistics variables are developed to indicate the availabilities of the trucks in a specific weight category for each 3PL provider. The prediction model using XGBoost regressor and permutation feature importance method provides highly acceptable performance with MAPE of 2.785% and shows the effectiveness of the developed operational statistics variables.

Warthin tumor, also known as papillary cystadenoma lymphomatosum is a benign neoplasm which occurs mostly in the parotid gland. It is the second most common benign neoplasm of the parotid gland, following pleomorphic adenoma. In occasion, the size of neoplasm grows slowly, and there is no symptom, except swelling. To prevent the recurrence, some surgeons prefer superficial parotidectomy, but the others prefer local resection with minimal surrounding tissue due to its low recurrence rate. We present a case of Warthin tumor of 55-year-old male.

Oral hyperpigmentation is common in patients older 40 years. But lesions in a newborn are unusual and congenital melanotic macule of the tongue has rarely been reported. A 2-month-old infant with 3 pigmented lesion on the right side of the dorsal tongue was evaluated. They were brown black but not homogeneous in color, smooth, nonblanchable, and nonpalpable, with irregular margins. We recommend excisional biopsy under general anesthesia because of possibility of malignancy, but parents refuse invasive procedure. On a following-up examination of the child at the age of 1 year, the pigmented lesions were unchanged. We report a case of congenital melanotic macules on the tongue and a review of literature about the lesion.

Poly(vinylidene chloride) (PVDC)-derived nanoporous carbons were prepared by various activation methods: heat-treatment under an inert atmosphere, steam activation, and potassium hydroxide (KOH) activation at 873, 1073, and 1273 K. The pore structures of PVDC-derived nanoporous carbons were characterized by the N2 adsorption technique at 77 K. Heat treatment in an inert atmosphere increased the specific surface area and micropore volume with elevating temperature, while the average micropore width near 0.65 nm was not significantly changed, reflecting the characteristic pore structure of ultramicroporous carbon. Steam activation for PVDC at 873 and 1073 K also yielded ultramicroporosity. On the other hand, the steam activated sample at 1273 K had a wider average micropore width of 1.48 nm, correlating with a supermicropore. The KOH activation increased the micropore volume with elevating temperature, which is accompanied by enlargement of the average micropore width from 0.67 to 1.12 nm. The average pore widths of KOH-activated samples were strongly governed by the activation temperature. We expect that these approaches can be utilized to simply control the porosity of PVDC-derived nanoporous carbons.

PET와 PET/CT의 검사 영상품질관리를 위해서는 F-18 방사능측정기의 정도관리가 필요하다. Ge-68/Ga-68 Rod Sources을 선원을 이용하여 의료기관에서 사용하고 있는 5종류의 방사능측정기의 방사능 측정의 정확도와 정밀도를 확인하였다. CRC-15R, CRC-15 PET, CRC-712M, CRC-15 베타 및 CRC-25PET에 대한 측정값과 기준값 사이의 방사능 양에 따른 상관관계는 0.99999 (P <0.0001)로 매우 높은 선형성을 보였다. 정확도 테스트에서 CRC-15R, CRC-15 PET, CRC-712M, CRC-15 베타 및 CRC-25PET 모델은 각각 -3.232 %, -1.342%, -2.815 %, -2.913 % 및 -3.089 %를 이었다. 국내와 국제기준인 정확도 ±10%, 정밀도 ±5% 이내로 기준을 만족하였고 반감기가 짧은 F-18에 비하여 경제성 있고 비교적 긴 기간 동안 안정적으로 정도관리가 가능하다는 것을 확인하였다.