The North Korean Economy: Sustainable or Muddling-Through?

Confronting the continuing economic sanctions, the flood disaster, and the COVID 19, North Korea is now in a critical phase whether the North Korean economy will shift to a sustainable economy or, as it has done in the past three decades, barely manage to maintain at a survival level. To explore the question, this study investigates North Korea's economic policy changes by extracting the keywords from the North Korean economic journal Economic Research, which is a representative state published document. We use a text mining approach to overcome limitations, such as the lack of objectivity and accuracy of the classification of topics in manual text analysis for North Korean studies. Contrary to the conventional assumption that the North Korean economic policies are driven by dogmatic Juche (self-reliance) ideology, we find that the strategy of economic policies differs depending on the leader and political and economic circumstances at the time. In particular, since Kim Jong-un assumed office in 2011, the topics have diversified, and now cover a wide range of subjects on capitalism. Nevertheless, without North Korea's decisive reform measures and international cooperation, it will be hard to observe that the North Korean economy can go beyond 'muddling-through' for sustainable development.1

Learning to Quantize Deep Networks by Optimizing Quantization Intervals with Task Loss

Reducing bit-widths of activations and weights of deep networks makes it efficient to compute and store them in memory, which is crucial in their deployments to resource-limited devices, such as mobile phones. However, decreasing bit-widths with quantization generally yields drastically degraded accuracy. To tackle this problem, we propose to learn to quantize activations and weights via a trainable quantizer that transforms and discretizes them. Specifically, we parameterize the quantization intervals and obtain their optimal values by directly minimizing the task loss of the network. This quantization-interval-learning (QIL) allows the quantized networks to maintain the accuracy of the full-precision (32-bit) networks with bit-width as low as 4-bit and minimize the accuracy degeneration with further bit-width reduction (i.e., 3 and 2-bit). Moreover, our quantizer can be trained on a heterogeneous dataset, and thus can be used to quantize pretrained networks without access to their training data. We demonstrate the effectiveness of our trainable quantizer on ImageNet dataset with various network architectures such as ResNet-18, -34 and AlexNet, on which it outperforms existing methods to achieve the state-of-the-art accuracy

Creation and annihilation of topological meron pairs in in-plane magnetized films

Merons which are topologically equivalent to one-half of skyrmions can exist only in pairs or groups in two-dimensional (2D) ferromagnetic (FM) systems. The recent discovery of meron lattice in chiral magnet Co8Zn9Mn3 raises the immediate challenging question that whether a single meron pair, which is the most fundamental topological structure in any 2D meron systems, can be created and stabilized in a continuous FM film? Utilizing winding number conservation, we develop a new method to create and stabilize a single pair of merons in a continuous Py film by local vortex imprinting from a Co disk. By observing the created meron pair directly within a magnetic field, we determine its topological structure unambiguously and explore the topological effect in its creation and annihilation processes. Our work opens a pathway towards developing and controlling topological structures in general magnetic systems without the restriction of perpendicular anisotropy and Dzyaloshinskii–Moriya interaction. © 2019, The Author(s).1

S-NPP VIIRS Day Night Band On-Board Solar Diffuser Calibration Validation Using the Scheduled Lunar Collections

Similar to the Reflective Solar Band (RSB) calibration, Suomi-National Polar-orbiting Partnership (S-NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) on-board calibration of Day Night Band (DNB) is based on the Solar Diffuser (SD) observations in the Low Gain State (LGS). DNB has a broad spectral response covering a wavelength range roughly from 500 nm to 900 nm with a large dynamic range from three different gain states called High Gain State (HGS), Mid Gain State (MGS), and LGS. The calibration of MGS and HGS is also dependent on the LGS gain estimation with the gain ratios for each gain state. Over the lifetime of S-NPP VIIRS operations, the LGS gains have been derived from the on-board SD observations since its launch in October 2011. In this study, the lifetime LGS gains are validated by the lunar calibration coefficients (defined as F-factors) using a lunar irradiance model called Global Space-based Inter-Calibration System (GSICS) Implementation of RObotic Lunar Observatory (ROLO) (GIRO). Using the moon as an independent on-orbit calibration source, the S-NPP VIIRS DNB on-board SD based radiometric calibration is validated by the lunar F-factors within two percent of the lunar F-factors in terms of the standard deviation in the long-term trends over nine years of the S-NPP VIIRS operation

Immunity to resistance? State-society relations and political stability in North Korea in a comparative perspective

Purpose - This article investigates whether certain social and subnational groups that have shown resistance against other one-party states might play a similar role in North Korea. Design/methodology/approach - Comparing the DPRK with various Communist regimes and Baathist party-states in Syria and Iraq, this article examines the following social groups as potential factors of resistance: industrial workers, private entrepreneurs, and religious, ethnic and regional identities. Findings - Resistance has not been wholly absent in North Korean, but the disaffected social groups have lacked sufficient bargaining power, while the state has occasionally refrained from steps that triggered protests in other countries. Practical implications - By comparing the DPRK with various types of regimes (pre-reform Communist systems, partially market-oriented Communist systems, and Baathist party-states), the article also seeks to investigate whether the dynamics of North Korean society is largely unique, or if it can be at least partially explained by means of analogy. Originality/value - While many studies have investigated the potential for collapse in North Korea, most of these were commonly focused on the capabilities of the North Korean state, rather than the peculiarities of the social environment in which it operated. © 2014 McFarland & Company, Inc.1

A Semantic Network Analysis of Changes in North Korea's Economic Policy

To shed light on the inner workings of policymaking in North Korea, this study examined the process behind economic policy change through an analysis of the official state economics journal. Semantic networks are used to trace the introduction and evolution of policies during four distinct economic periods in North Korean history between 1986 and 2009. Although reform is catalyzed by political and economic crises, the emergence of new policy topics occurs incrementally prior to change. Specifically, new policy discourse tends to emerge in gradual and cautious ways but policy change occurs swiftly in periods of crisis. During periods of stability, the state retreats to the centralized socialist economic system, often through coercion and force. This view of the policy process suggests that foundations of economic reforms in North Korea are yet weak and instable, and policy reform will continue to be vulnerable to the political influence of conservatives.1